0001193125-23-196280 | S-4 | XBRL Viewer | Frequency Therapeutics INC

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Subsequent Events	3 Months Ended	12 Months Ended
Subsequent Events	Mar. 31, 2023	Dec. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	18. Subsequent events The Company has evaluated subsequent events for recognition, remeasurement and disclosure purposes through May 12, 2023, the date which the consolidated financial statements were available to be issued. The identified subsequent event is as follows: On April 3, 2023, the Company prepaid the remaining $11,667 due under the term loan. Upon prepayment of the term loan, the final payment of $150, which the Company had been accruing over the term of the loan, was also paid. The Company was not subject to any prepayment premium as the prepayment occurred after the second anniversary of the closing date. Refer to Note 7, “Debt”. On April 4, 2023, the Company’s termination of the MEE License Agreement became final. No termination costs were incurred as a result of terminating this license agreement. Refer to Note 14, “License agreements”. On April 6, 2023, the Company provided written notice of termination of the MIT License Agreement. Pursuant to the terms of the agreement, the Company has the right to terminate for any reason upon a 3-month prior written notice. No termination costs will be incurred as a result of terminating this license agreement. Refer to Note 14, “License agreements”. On April 14, 2023, the Astellas Agreement was terminated in its entirety. No termination costs will be incurred as a result of terminating this collaboration agreement. Refer to Note 13, “Collaboration agreement”. On April 28, 2023, the Company’s termination of the CALIBR License Agreement became final. No termination costs were incurred as a result of terminating this license agreement. Refer to Note 14, “License agreements”.	19. Subsequent events The Company has evaluated subsequent events for recognition, remeasurement and disclosure purposes through March 10, 2023, the date which the consolidated financial statements were available to be issued. The identified subsequent event is as follows: On February 13, 2023, the Company announced a restructuring in which its hearing program was discontinued. As a result, the Company reduced its workforce by approximately 55% to better align with the needs of its business. The total personnel costs related to the restructuring are estimated to be approximately $4,000 in future cash outlays primarily related to severance costs and related expenses.

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 40,853	$ 51,954	$ 79,635
Short-term marketable securities	25,797	31,143	51,072
Prepaid expenses and other current assets	2,643	4,396	4,041
Total current assets	69,293	87,493	134,748
Long-term marketable securities		0	11,719
Property and equipment, net	1,832	2,739	5,522
Right of use assets	28,350	28,980	31,350
Restricted cash	1,699	1,699	1,699
Other long-term assets	327	327	320
Total assets	101,501	121,238	185,358
Current liabilities:
Accounts payable	2,715	3,114	2,748
Accrued expenses	5,567	5,891	6,101
Lease liabilities, current portion	2,088	2,021	1,747
Term loan, current portion	11,667	10,000	833
Total current liabilities	22,037	21,026	11,429
Lease liabilities, net of current portion	26,215	26,761	28,851
Term loan, net of current portion	0	4,167	14,167
Other long-term liabilities	0	89	87
Total liabilities	48,252	52,043	54,534
Stockholders' equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized, no shares issued or outstanding at March 31, 2023 and December 31, 2022	0	0	0
Common stock, $0.001 par value; 200,000,000 shares authorized, 35,751,956 and 35,262,083 shares issued and outstanding at March 31, 2023 and December 31, 2022, respectively	36	35	35
Additional paid-in capital	334,485	331,023	310,936
Accumulated other comprehensive income	(64)	(198)	(62)
Accumulated deficit	(281,208)	(261,665)	(180,085)
Total stockholders' equity	53,249	69,195	130,824
Total liabilities and stockholders' equity	$ 101,501	$ 121,238	$ 185,358

Collaboration Agreement - Additional Information (Details) - License and Collaboration Agreement - Astellas Pharma LLC - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended	12 Months Ended
	Jul. 31, 2019	Mar. 31, 2023	Mar. 31, 2022	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Payments received under collaboration agreement	$ 80,000
Agreement termination notice period	60 days
Right to terminate agreement if breach remains uncured	90 days
Right to terminate agreement incase of nonpayment	45 days
Transaction price allocated to single combined performance obligation				$ 80,000
Upfront fee recognized as revenue	$ 80,000
joint cost		$ 14	$ 193		$ 392	$ 885
Phase 2b Clinical Trial \| Europe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	65,000
Phase 2b Clinical Trial \| Asia
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	25,000
Phase 3 Clinical Trial \| Europe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	100,000
Phase 3 Clinical Trial \| Asia
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	40,000
Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive	230,000
Revenue recognized commercialization milestone payments to receive	315,000
Potential commercial milestone payments eligible to receive upon successful commercialization	$ 315,000

Cover Page	3 Months Ended
Cover Page	Mar. 31, 2023
Document Type	S-4
Amendment Flag	false
Entity Central Index Key	0001703647
Entity Registrant Name	Frequency Therapeutics, Inc.
Entity Incorporation State Country Code	DE
Entity Tax Identification Number	47-2324450
Entity Address Address Line	75 Hayden Avenue
Entity Address, Address Line Two	Suite 300
Entity Address City Or Town	Lexington
Entity Address State Or Province	MA
Entity Address Postal Zip Code	02421
City Area Code	781
Local Phone Number	315-4600
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Primary SIC Number	2834
Business Contact [Member]
Entity Address Address Line	75 Hayden Avenue
Entity Address, Address Line Two	Suite 300
Entity Address City Or Town	Lexington
Entity Address State Or Province	MA
Entity Address Postal Zip Code	02421
City Area Code	781
Local Phone Number	315-4600
Contact Personnel Name	David L. Lucchino

Sublease - Summary of future sublease income (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Leases [Abstract]
2023	$ 1,779	$ 2,371
2024	1,383	1,383
Total future sublease income	$ 3,162	$ 3,754

Investments - Schedule of classified as available-for-sale and recorded at fair value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Fair Value, Separate Account Investment [Line Items]
Amortization Cost	$ 25,799	$ 31,280
Unrealized Loss	(2)	(317)
Fair Market Value	25,797	31,143
Short-term marketable securities
Fair Value, Separate Account Investment [Line Items]
Amortization Cost	25,799	31,280
Unrealized Loss	(2)	(317)
Fair Market Value	$ 25,797	$ 31,143

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of significant accounting policies

Basis of presentation

The accompanying consolidated financial statements have been prepared in accordance with accounting standards set by the Financial Accounting Standards Board (FASB). The FASB sets generally accepted accounting principles (GAAP) that the Company follows to ensure its financial condition, results of operations, and cash flows are consistently reported. References to GAAP issued by the FASB in these notes to the consolidated financial statements are to the FASB

Accounting Standards

Codification (ASC).

Principles of consolidation

The consolidated financial statements include the accounts of Frequency Therapeutics, Inc. and its wholly owned subsidiaries Frequency Therapeutics Securities Corporation, Frequency Therapeutics PTY, LTD and Frequency Japan through the date of its dissolution. All intercompany transactions and balances have been eliminated.

Use of estimates

The preparation of the Company’s consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, expenses and related disclosure of contingent assets and liabilities at the date of the consolidated financial statements and reported amounts of expenses during the reporting period. On an ongoing basis, the Company’s management evaluates its estimates, which include but are not limited to management’s judgments of accrued expenses, revenue recognition, fair value of common stock, valuation of share-based awards, present value of lease liabilities and income taxes. Actual results could differ from those estimates.

Comprehensive loss

Components of comprehensive loss, including net loss, are reported in the financial statements in the period in which they are recognized. Other comprehensive loss is defined as the change in equity during a period from transactions and other events and circumstances from

non-owner

sources. Net loss and other comprehensive loss are reported net of any related tax effect to arrive at comprehensive loss. Comprehensive loss includes net loss as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders which for the years ended December 31, 2022 and 2021 consist of unrealized loss on marketable securities.

Segment information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company and the Company’s chief operating decision-maker, the Company’s chief executive officer, view the Company’s operations and manage its business as a single operating segment, which is in the business of developing therapeutics to activate a person’s innate regenerative potential to restore function.

Foreign currency

All periods presented are reported in US dollars. The functional currency for entities outside the United States is the US dollar. Realized and unrealized gains and losses from foreign currency transactions are reflected in the consolidated statements of operations as other expense. During the years ended December 31, 2022 and 2021 the Company recorded $5 of foreign currency exchange loss and $16 of foreign currency exchange gain, respectively.

Cash and cash equivalents

The Company considers all highly liquid investments with an original maturity of six months or less at acquisition to be cash equivalents which are stated at fair market value. Cash and cash equivalents at December 31, 2022 and 2021 consists entirely of cash and money market funds.

Restricted cash

The Company has $1,699 of restricted cash as of December 31, 2022 and December 31, 2021, which represents a security deposit on the Company’s Lexington, Massachusetts facility.

Marketable securities

Marketable securities represent holdings of

available-for-sale

marketable debt securities in accordance with the Company’s investment policy. Short-term marketable securities mature within one year from the balance sheet date while long-term marketable securities mature after one year. Investments in marketable securities are recorded at fair value, with any unrealized gains and losses reported within accumulated other comprehensive income as a separate component of stockholders’ equity until realized or until a determination is made that an other-than-temporary decline in market value has occurred. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion are reflected as a component of other expense. Interest on securities sold is determined based on the specific identification method and reflected as interest income. Any realized gains or losses on the sale of investment are reflected as realized gain (loss) on investments.

Concentration of credit risk and

off-balance

sheet risk

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents and marketable securities. The Company maintains its cash, cash equivalents, and

restricted cash at several accredited financial institutions, in amounts that exceed federally insured limits. Marketable securities consist of short term and long term investments. Management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which its money market accounts are maintained.

The Company has no significant

off-balance

sheet arrangements such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.

Significant suppliers

The Company is dependent on third-party manufacturers to supply products for research and development activities of its programs, including preclinical and clinical testing. In particular, the Company relies and expects to continue to rely on a single manufacturer of its product candidates for use in clinical trials. The Company would be adversely affected by a significant interruption in the supply of product for use in clinical programs.

Fair value measurements

Fair value is defined as the price that would be received upon sale of an asset or paid to transfer a liability between market participants at measurement dates. ASC Topic 820,

Fair Value Measurement

(ASC 820), establishes a three-level valuation hierarchy for instruments measured at fair value. The hierarchy is based on the transparency of inputs to the valuation of an asset or liability as of the measurement date. The hierarchy defines three levels of valuation inputs, of which the first two are considered observable and the last is considered unobservable:

Level 1

Quoted prices in active markets for identical assets or liabilities.

Level 2

Inputs other than quoted prices included within Level 1 that are either directly or indirectly observable, such as quoted market prices, interest rates and yield curves.

Level 3

Unobservable inputs developed using estimates or assumptions developed by the Company, which reflect those that a market participant would use in pricing the asset or liability.

To the extent that the valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

The carrying amounts reflected in the consolidated balance sheet for prepaid expenses and other current assets, accounts payable, accrued expenses, other liabilities, and term loan are shown at their historical values which approximate their fair values.

Property and equipment, net

Property and equipment consist of lab equipment, furniture and office equipment and software recorded at cost. These amounts are depreciated using the straight-line method over the estimated useful lives of the assets as follows:


	Estimated useful life
Lab equipment		3 years
Software		3 years
Furniture and office equipment		3 years

Upon retirement or sale, the cost of the assets disposed of and the related accumulated depreciation are eliminated from the balance sheet and related gains or losses are reflected in the consolidated statements of operations.

Impairment of long-lived assets

The Company continually evaluates long-lived assets for potential impairment when events or changes in circumstances indicate the carrying value of the assets may not be recoverable. Recoverability is measured by comparing the book values of the assets to the expected future net undiscounted cash flows that the assets are expected to generate. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the book values of the assets exceed their fair value. The Company did not recognize any impairment losses for the years ended December 31, 2022 and 2021.

Research and development costs and accruals

Research and development expenses include salaries and benefits, materials and supplies, preclinical and clinical trial expenses, stock-based compensation expense, depreciation of equipment, contract services and other outside expenses. The Company has entered into various research and development-related contracts with research institutions, contract research organizations, contract manufacturers and other companies. These agreements are generally cancelable, and related payments are recorded as research and development expenses as incurred. Costs of certain development activities, such as manufacturing, preclinical and clinical trial expenses, are recognized based on an evaluation of the progress to completion of specific tasks. Payments for these activities are based on the terms of the individual arrangements, which may differ from the pattern of costs incurred, and are reflected in the consolidated financial statements as prepaid or accrued research and development costs. Nonrefundable advance payments for goods or services to be received in the future for use in research and development activities are deferred and capitalized. The capitalized amounts are expensed as the related goods are delivered or the services are performed. Costs incurred in obtaining technology licenses are charged to research and development expense as acquired

in-process

research and development if the technology licensed has not reached technological feasibility and has no alternative future use.

Leases

The Company accounts for leases under ASC 842,

Leases

. The Company determines if an arrangement is, or contains, a lease at inception and, if so, records a

right-of-use

(ROU) asset and a lease liability on the consolidated balance sheet for any lease with a term longer than 12 months.

ROU assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments to be made over the lease term. The ROU asset also includes any lease payments made at or before the lease commencement date and excludes lease incentives received. As the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at the lease commencement date in determining the present value of lease payments. The lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Operating lease expense is recognized on a straight-line basis over the lease term. The Company has elected to not apply the recognition requirements of ASC 842 for short-term leases, which is defined as a lease that, at the lease commencement date, has a lease term of 12 months or less and does not include an option to purchase the underlying asset that the Company is reasonably certain to exercise.

For real estate lease agreements entered into or modified after the adoption of ASC 842 that include lease and

non-lease

components, the Company has elected to account for the lease and

non-lease

components, such as common area maintenance charges, as a single lease component.

Collaborative arrangements

The Company analyzes its collaborative arrangements to assess whether they are within the scope of ASC 808,

Collaborative Arrangements

(ASC 808) to determine whether such arrangements involve joint operating activities performed by parties that are both active participants in the activities and exposed to significant risks and rewards dependent on the commercial success of such activities. This assessment is performed throughout the life of the arrangement based on changes in the responsibilities of all parties in the arrangement. For collaboration arrangements within the scope of ASC 808 that contain multiple elements, the Company first determines which elements of the collaboration are deemed to be within the scope of ASC 808 and those that are more reflective of a vendor-customer relationship (e.g., a licensing arrangement) where the contracted party has obtained goods or services that are an output of the Company’s ordinary activities in exchange for a consideration and therefore within the scope of ASC 606,

Revenue from Contracts with Customers

(ASC 606). For those elements of the arrangement that are accounted for pursuant to ASC 606, including those to which ASC 606 is applied by analogy, the Company applies the five-step model described in the Company’s revenue recognition policy. For elements of collaborative arrangements that are accounted for pursuant to ASC 808, an appropriate and rational recognition method is determined and applied consistently. Reimbursements from the counterparty that are the result of a collaborative relationship with the counterparty, instead of a customer relationship, such as

co-development

or clinical activities, are recorded as a reduction to research and development expense as the services are performed. Similarly, amounts that are owed to a collaboration partner related to the

co-development

clinical activities are recognized as research and development expense.

The Company enters into

out-licensing

agreements that are within the scope of ASC 606. The terms of such

out-license

agreements include licenses to functional intellectual property (IP), given the functionality of the intellectual property is not expected to change substantially as a result of the licensor’s ongoing activities. Such arrangements typically include payment of one or more of the following:

non-refundable

up-front

license fees; reimbursement of certain costs; development and regulatory milestone payments and milestone payments based on the level of sales; and royalties on net sales of licensed products.

The Company considers the economic and regulatory characteristics of the licensed IP, research, development, manufacturing and commercialization capabilities of the licensee and the availability of the associated expertise in the general marketplace to determine if it has standalone value at the inception of the licensing arrangement, which would make the license distinct. In addition, the Company considers whether the licensee can benefit from a promise for its intended purpose without the receipt of any additional good or services promised in the contract, whether the value of the license is dependent on the remaining goods and services, whether there are other vendors that could provide the remaining promise, and whether the license is separately identifiable from the remaining good and services. For licenses that are combined with other goods and services, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of progress and related revenue recognition. The measure of progress, and thereby periods over which revenue should be recognized, are subject to estimates by management and may change over the course of the research and development and licensing agreement. Such a change could have a material impact on the amount of revenue the Company records in future periods.

Revenue is allocated to the licensed IP on a relative standalone selling price basis and, for functional IP, is recognized at a point when the licensed IP is made available for the customer’s use and benefit, which generally occurs at the inception of the arrangement. However, in cases, where the functionality of the IP is expected to substantively change as a result of activities of the Company that do not transfer additional promised goods or services, or in cases, where there is an expectation that the Company will undertake activities to change the standalone functionality of the IP and the customer is contractually or practically required to use the latest version of the IP, revenue for the license to functional IP is recognized over time.

Development and regulatory milestone fees, which are a type of variable consideration, are recognized as revenue to the extent that it is probable that a significant reversal will not occur. The Company recognizes royalty revenue and sales-based milestones at the later of (i) when the related sales occur, or (ii) when the performance obligation to which the royalty has been allocated has been satisfied.

The Company has entered into a collaboration arrangement with Astellas Pharma Inc. (Astellas), as further described in Note 13, “

Collaboration agreement

”, of notes to consolidated financial statements.

Revenue recognition

The Company accounts for contracts with customers in accordance with ASC 606, including all amendments thereto. This standard applies to all contracts with customers, except for contracts that are within the scope of other standards, such as collaborative arrangements and leases. The Company’s disclosure within the below sections or elsewhere within these consolidated financial statements reflects the Company’s accounting policies in compliance with this standard.

Under ASC 606, an entity recognizes revenue when or as its customer obtains control of promised goods or services, in an amount that reflects the consideration that the entity expects to receive in exchange for those goods or services. To recognize revenue for arrangements that an entity determines are within the scope of ASC 606, the entity performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price, including variable consideration, if any; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies its performance obligations. The Company only applies the five-step model to contracts when it is probable that the entity will collect substantially all of the consideration to which it will be entitled in exchange for the goods or services it transfers to the customer. Once a contract is determined to be within the scope of ASC 606, the Company assesses the goods or services promised within each contract and identifies as a performance obligation each promise to transfer to the customer either (a) a good or service (or bundle of goods and services) that is distinct, or (b) a series of distinct goods and services that are substantially the same and have been the same pattern of transfer to the customer.

The Company assesses whether each promised good or service is distinct for the purpose of identifying the performance obligations in the contract. This assessment involves subjective determinations and requires management to make judgments about the individual promised goods or services and whether such are separable from the other aspects of the contractual relationship. Promised goods and services are considered distinct provided that: (i) the customer can benefit from the good or service either on its own or together with other resources that are readily available to the customer (that is, the good or service is capable of being distinct) and (ii) the entity’s promise to transfer the good or service to the customer is separately identifiable from other promises in the contract (that is, the promise to transfer the good or service is distinct within the context of the contract). In assessing whether a promised good or service is distinct, the Company considers factors such as the research, manufacturing and commercialization capabilities of the collaboration partner (the “customer” in this type of arrangement) and the availability of the associated expertise in the general marketplace. The Company also considers the intended benefit of the contract in assessing whether a promised good or service is separately identifiable from other promises in the contract. If a promised good or service is not distinct, an entity is required to combine that good or service with other promised goods or services until it identifies a bundle of goods or services that is distinct. For each arrangement that results in revenues, the Company identifies all performance obligations, which may include, for example, a license to IP and

know-how,

research and development activities, and/or manufacturing services.

In addition to any upfront payment, if the consideration promised in a contract includes a variable amount, the Company estimates the amount of consideration to which it will be entitled in exchange for transferring the promised goods or services to a customer. The Company determines the amount of variable consideration by using the expected value method or the most likely amount method. The Company includes the estimated

variable consideration in the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur. At the end of each subsequent reporting period, the Company

re-evaluates

the estimated variable consideration included in the transaction price and any related constraint, and if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative

catch-up

basis in the period of adjustment.

If an arrangement includes development and regulatory milestone payments, the Company evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price using the most likely amount method. There is considerable judgment involved in determining whether it is probable that a significant revenue reversal would not occur. If it is probable that a significant revenue reversal will not occur, the associated milestone value is included in the transaction price. Milestone payments that are not within the control of the Company or of the licensee such as regulatory approvals, are generally not considered probable of being achieved until those approvals are received. At the end of each subsequent reporting period, the Company

re-evaluates

the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative

catch-up

basis, which would affect revenues and earnings in the period of adjustment.

For contracts that include sales-based royalties (including milestone payments based on the level of sales) promised in the exchange for licenses of intellectual property, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes royalty revenue and sales-based milestone payments at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied. In determining the transaction price, the Company adjusts the promised amount of consideration for the effects of the time value of money if the timing of payments provides the Company or the Company’s customer with a significant benefit of financing the transfer of goods and services. The Company does not assess whether a contract has a significant financing component if the expectation at contract inception is such that the period between payment by the licensees and the transfer of the promised goods or services to the licensees will be one year or less. The Company assesses each of its revenue generating arrangements in order to determine whether a significant financing component exists. The Company recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) each performance obligation is satisfied, either at a point in time or over time. For performance obligations satisfied over time, the Company measures progress toward completion of its performance obligations using an input method based on the Company’s efforts and inputs to satisfy its performance obligations relative to total expected inputs to the satisfaction of that performance obligation.

Amounts received from a customer prior to revenue recognition are recorded as deferred revenue. Amounts received from a customer that are expected to be recognized as revenue within the 12 months following the balance sheet date are classified as a current liability in the accompanying consolidated balance sheets.

Patent costs

The Company expenses patent application and related legal costs as incurred and classifies such costs as general and administrative expenses in the accompanying consolidated statements of operations.

Stock-based compensation

The Company accounts for its stock-based compensation in accordance with ASC Topic 718,

Compensation—Stock Compensation

(ASC 718). ASC 718 requires all share-based payments to employees and directors to be recognized as expense in the consolidated statements of operations and comprehensive loss based on their grant date fair values. The Company adopted FASB Accounting Standards Update (ASU)

2016-09

which identifies areas for simplification of several areas of share-based payment transactions. The Company treats

non-employee

grants in a manner consistent with employee grants. The Company estimates the fair value of options granted using the Black-Scholes option pricing model for stock option grants to both employees and

non-employees.

The Company believes the fair value of the stock options granted to

non-employees

is more reliably determinable than the fair value of the services provided.

The Black-Scholes option pricing model requires inputs based on certain subjective assumptions, including (a) the expected stock price volatility, (b) the expected term of the award, (c) the risk-free interest rate and (d) expected dividends. Due to the lack of sufficient company-specific historical and implied volatility data, the Company has based its computation of expected volatility on the historical volatility of a representative group of public companies with similar characteristics to the Company, including stage of product development and life science industry focus. The historical volatility is calculated based on a period of time commensurate with the expected term assumption. The Company uses the simplified method as prescribed by the SEC Staff Accounting Bulletin No. 107, Share-Based Payment, to calculate the expected term for options granted to employees as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term. The expected term is applied to the stock option grant group as a whole, as the Company does not expect substantially different exercise or post-vesting termination behavior among its employee population. For options granted to

non-employees,

the Company utilizes the contractual term of the share-based payment as the basis for the expected term assumption. The risk-free interest rate is based on a treasury instrument whose term is consistent with the expected term of the stock options. The expected dividend yield is assumed to be zero as the Company has never paid dividends and has no current plans to pay any dividends on its common stock.

The Company expenses the fair value of its share-based compensation awards to employees and

non-employees

on a straight-line basis over the requisite service period, which is generally the vesting period.

Income taxes

The Company accounts for income taxes using the asset and liability method in accordance with ASC Topic 740,

Income Taxes

(ASC 740) which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the consolidated financial statements or in the Company’s tax returns. Deferred tax assets and liabilities are determined on the basis of the differences between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. Changes in deferred tax assets and liabilities are recorded in the provision for income taxes. The Company assesses the likelihood that its deferred tax assets will be recovered from future taxable income and, to the extent it believes, based upon the weight of available evidence, that it is more likely than not that all or a portion of the deferred tax assets will not be realized, a valuation allowance is established through a charge to income tax expense. Potential for recovery of deferred tax assets is evaluated by estimating the future taxable profits expected and considering prudent and feasible tax planning strategies. At December 31, 2022 and 2021, the Company has concluded that a full valuation allowance is necessary for its deferred tax assets (see Note 11,

“

Income taxes

”).

Net loss per share

Basic net loss per share is computed by dividing net loss by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed using the weighted-average number of shares of common stock outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. Diluted net loss per share is the same as basic net loss per share for the years ended December 31, 2022 and 2021 since all potential shares of common stock instruments are anti-dilutive as a result of the loss for such periods.

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Year Ended December 31,
	2022			2021
Numerator:
Net loss	$	(81,580	)	$	(84,686	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,075,924			34,351,274

Net loss per share-basic and diluted	$	(2.33	)	$	(2.47	)

Recently issued and adopted accounting pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. The Company is an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012, as amended (Jobs Act). The Jobs Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. Thus, an emerging growth company can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company elected to avail itself of this extended transition period and, as a result, we will not be required to adopt new or revised accounting standards on the relevant dates on which adoption of such standards is required for other public companies.

In June 2016, the FASB issued ASU

No. 2016-13,

Financial Instruments—Credit Losses

(Topic 326): Measurement of Credit Losses on Financial Instruments. The FASB has subsequently issued amendments to ASU

2016-13,

which have the same effective date and transition date. These standards require that credit losses be reported using an expected losses model rather than the incurred losses model that was previously used, and establishes additional disclosures related to credit risks. For

available-for-sale

debt securities with unrealized losses, this standard now requires allowances to be recorded instead of reducing the amortized cost of the investment. These standards limit the amount of credit losses to be recognized for

available-for-sale

debt securities to the amount by which carrying value exceeds fair value and requires the reversal of previously recognized credit losses if fair value increases. The Company adopted this standard on January 1, 2023 and it did not have a material impact on the consolidated financial statements.

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Payroll and employee related expenses	$ 3,831	$ 4,216	$ 4,375
Professional fees	550	377	767
Third-party research and development expenses	457	773	840
Other	729	525	119
Total	$ 5,567	$ 5,891	$ 6,101

Property and Equipment

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Property and Equipment

5. Property and equipment

Property and equipment include the following:


	March 31, 2023			December 31, 2022
Lab equipment	$	5,747		$	5,706
Furniture and office equipment		3,238			3,238
Software		291			291

Total		9,276			9,235
Accumulated depreciation		(7,444	)		(6,496	)

Property and equipment, net	$	1,832		$	2,739

The Company recognized $1,000 and $726 of depreciation expense for the three months ended March 31, 2023 and 2022, respectively. The Company accelerated depreciation of $360 on certain lab equipment for the three months ended March 31, 2023 as discussed in Note 17,

“Restructuring”.

5. Property and equipment

Property and equipment include the following:


	December 31, 2022			December 31, 2021
Lab equipment	$	5,706		$	6,177
Furniture and office equipment		3,238			3,238
Software		291			291

Total		9,235			9,706
Accumulated depreciation		(6,496	)		(4,184	)

Property and equipment, net	$	2,739		$	5,522

The Company recognized $2,766 and $2,775 of depreciation expense for the years ended December 31, 2022 and 2021, respectively.

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 1,000	$ 726	$ 2,766	$ 2,775
Accelerated depreciation charges	$ 360

Stock-based Compensation - Summary of Stock Option Activity with in 2014 Stock Incentive Plan and 2019 Incentive Award Plan (Details) - 2014 and 2019 Plan - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Beginning balance	5,742,053	6,830,037	6,816,798
Number of shares, Granted	27,350	221,176	1,357,426
Number of shares, Exercised	(2,969)	(10,047)	(642,314)
Number of shares, Forfeited	(166,346)	(1,299,113)	(701,873)
Number of shares, Ending balance	5,600,088	5,742,053	6,830,037	6,816,798
Number of shares, Options exercisable	4,789,470	4,579,486
Number of shares, Options unvested	810,618	1,162,567
Weighted average exercise price, Beginning balance	$ 2.35	$ 5.35	$ 10.11
Weighted average exercise price, Granted	4.66	1.78	32.76
Weighted average exercise price, Exercised	0.07	1.24	2.02
Weighted average exercise price, Forfeited	2.2	18.04	16.48
Weighted average exercise price, Ending balance	2.36	2.35	$ 5.35	$ 10.11
Weighted average exercise price, Options exercisable	2.4	2.4
Weighted average exercise price, Options unvested	$ 2.13	$ 2.12
Weighted average remaining contractual term (in years), Outstanding	5 years 7 months 17 days	6 years 8 months 8 days	7 years 9 months 3 days	8 years 5 months 12 days
Weighted average remaining contractual term (in years), Granted	8 years 7 months 9 days	8 years 3 months 25 days	8 years 25 days
Weighted average remaining contractual term (in years), Options exercisable as of March 31, 2023	5 years 3 months 14 days	6 years 4 months 20 days
Weighted average remaining contractual term (in years), Options unvested as of March 31, 2023	7 years 7 months 24 days	7 years 10 months 2 days
Aggregate intrinsic value, Outstanding	$ 9,114	$ 6,987	$ 171,415
Aggregate intrinsic value, Exercised	1	37	11,652
Aggregate intrinsic value, Outstanding	4	9,114	$ 6,987	$ 171,415
Aggregate intrinsic value, Options exercisable	4	7,071
Aggregate intrinsic value, Options unvested	$ 0	$ 2,043

Stock-based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		12 Months Ended
	Aug. 17, 2022	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Sep. 17, 2019	Nov. 13, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance		7,290,493		6,730,269	8,382,667
Options vesting period				4 years
Weighted-average grant date fair value of stock options granted		$ 3.58	$ 3.55	$ 1.58	$ 22.39
Total grant date fair value of stock options vested		$ 2,874	$ 5,097	$ 14,219	$ 16,304
Underwater Options reduced	$ 2.14
Cost related to stock options, stock based compensation	$ 2,505	170		1,630	2,505
Expenses of Stock Based Compensation to be Recognized over vesting period of options		705		875
Stock-based compensation expense		3,431	5,266
Total unrecognized stock-based compensation expense relating to unvested stock options		$ 17,610		$ 19,537	$ 39,112
Unrecognized unvested stock options, restricted stock awards and restricted stock units, weighted-average period		1 year 8 months 19 days		1 year 6 months 18 days	2 years 5 months 26 days
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 839	2,301	$ 19,831
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 2,592	$ 2,965		$ 21,750
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options expiration period				10 years
2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance							8,550,415
Common stock, shares available for future grants				0
2019 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of authorized shares reserved for issuance						3,100,000
Period for automatic increase in common stock available for future issuance				10 years
Percentage of shares issued from outstanding number of shares				4.00%
Common stock future issuance, description				In addition, the number of shares of common stock available for issuance under the 2019 Plan will be automatically increased on the first day of each calendar year during the ten-year term of the 2019 Plan, beginning with January 1, 2020 and ending with January 1, 2029, by the amount equal to 4% of the outstanding number of shares of the Company’s common stock on December 31 of the preceding calendar year or such lesser amount as determined by the Company’s board of directors.

Restructuring - Summary of Restructuring-related charges (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 3,970
Research and Development
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	2,421
General and Administrative
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	1,549
Accelerated FX-322 charges
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	129
Accelerated FX-322 charges \| Research and Development
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	129
Severance and other benefit-related costs
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	3,481
Severance and other benefit-related costs \| Research and Development
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	1,932
Severance and other benefit-related costs \| General and Administrative
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	1,549
Accelerated depreciation charges [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Charges	$ 360

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Research and License Agreements - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands				1 Months Ended			3 Months Ended	12 Months Ended
	Apr. 06, 2023	Mar. 29, 2023	Feb. 21, 2023	Feb. 28, 2019	Sep. 30, 2018	Dec. 31, 2016	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Dr. Langer
Research And Development Arrangement Contract To Perform For Others [Line Items]
Payment to director								$ 11	$ 6
MIT
Research And Development Arrangement Contract To Perform For Others [Line Items]
Description of future development obligations								The Company’s future development obligations are: (i) to commence a Phase 3 clinical trial for such Product within five years of the IND filing for such product, (ii) to file a New Drug Application or equivalent with the FDA or comparable European regulatory agency for such Product within nine years of the IND filing for such Product, and (iii) to make a first commercial sale of such Product within 11 years of the IND filing for such Product.
License fee payment						$ 50
Percentage of shares of common stock issued						5.00%
Description of conditions to terminate license agreement							The Company has the right to terminate for any reason upon a 3-month prior written notice.	The Company has the right to terminate for any reason upon a 3-month prior written notice. MIT shall have the right to terminate if the Company ceases to carry on any business related to the MIT License Agreement. MIT may terminate the MIT License Agreement for the Company’s material breach uncured within ninety (90) days (or thirty (30) days in the case of nonpayment). MIT may also terminate the MIT License Agreement if the Company or our affiliates commence any action against MIT to declare or render any claim of the licensed patent rights invalid, unpatentable, unenforceable, or non-infringed (a patent challenge), or if our sublicensee commences such actions and the Company does not terminate such sublicense within thirty (30) days after MIT’s demand. MIT has the right to increase all payments due, instead of terminating the MIT License Agreement in the case of a patent challenge.
Right to terminate agreement upon prior written notice						3 months
Right to terminate agreement if breach remains uncured						90 days
Right to terminate agreement incase of nonpayment						30 days
Right to terminate agreement upon prior written notice if insolvent	3 months
MIT \| Maximum
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payments						$ 2,900
MIT \| Patent License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement entered date						2016-12
CALIBR
Research And Development Arrangement Contract To Perform For Others [Line Items]
License fee payment					$ 1,000
Percentage of Royalty on Sublicense Revenue					50.00%
Milestone payments					$ 26,000
Description of conditions to terminate license agreement		the Company sent CALIBR a notice stating that the Company would be terminating the CALIBR License Agreement in 30 days’ time.						The Company may also elect to terminate its license to one or more licensed patents in any or all jurisdictions by giving ninety (90) days’ prior written notice to CALIBR. CALIBR may terminate the CALIBR License Agreement for material breach uncured within thirty (30) days. CALIBR has the right to terminate or reduce the license to a non-exclusive license if the Company fails to use diligent efforts to develop and commercially exploit CALIBR Licensed Products.
Right to terminate agreement if breach remains uncured		30 days			30 days
Right to terminate licensed patents upon prior written notice					90 days
CALIBR \| Patent License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement entered date					2018-09
MEE
Research And Development Arrangement Contract To Perform For Others [Line Items]
License fee payment				$ 20
Description of conditions to terminate license agreement			the Company sent MEE a notice stating that the Company would be terminating the MEE License Agreement in 30 business days’ time.					The Company has the right to terminate the MEE License Agreement at will by giving thirty (30) business days advance written notice to MEE. MEE has the right to terminate the MEE License Agreement if the Company fails to make any payment due within thirty (30) business days
Right to terminate agreement upon prior written notice				30 days
Right to terminate agreement if breach remains uncured			30 days	60 days
Right to terminate agreement incase of nonpayment				30 days
Right to terminate agreement upon prior written notice if insolvent				45 days
MEE \| Maximum
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payments				$ 350
Annual License Fee Per Share							$ 7.5	$ 7.5
MEE \| Minimum
Research And Development Arrangement Contract To Perform For Others [Line Items]
Royalty Expense Per Share								15
Annual License Fee Per Share							$ 5	$ 5
MEE \| Non-Exclusive Patent License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement entered date				2019-02

Stock-based Compensation - Summary of Grant-date Fair Value of Stock Options Granted on Weighted Average Basis (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Risk-free interest rate	3.60%	3.00%	0.50%
Expected term (in years)	6 years	6 years	6 years
Expected volatility	92.00%	80.00%	79.80%
Expected dividend yield	0.00%	0.00%	0.00%

Restructuring - Schedule of incurred charges due to restructuring (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Restructuring and Related Activities [Abstract]
Accelerated depreciation charges		$ 360
Accelerated Hearing Program Charges		129
Severance and other benefit-related costs	$ 359	$ 3,481	$ 3,840	$ 3,840

Investments (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Investments, Debt and Equity Securities [Abstract]

Schedule of classified as available-for-sale and recorded at fair value

The following tables summarize the Company’s investments, all of which are classified as

available-for-sale

and recorded at fair value:


	March 31, 2023
	Amortization Cost		Unrealized Loss			Fair Market Value
Short-term marketable securities		25,799		(2	)		25,797

	$	25,799	$	(2	)	$	25,797


	December 31, 2022
	Amortization Cost		Unrealized Loss			Fair Market Value
Short-term marketable securities		31,280		(317	)		31,143

	$	31,280	$	(317	)	$	31,143

Schedule of debt securities in an unrealized loss position

The following tables summarize the Company’s debt securities in an unrealized loss position, aggregated by length of time in a continuous unrealized loss position.


	March 31, 2023
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities in unrealized loss position	$	8,407	$	(21	)	$	9,943	$	(54	)	$	18,350	$	(75	)

	$	8,407	$	(21	)	$	9,943	$	(54	)	$	18,350	$	(75	)


	December 31, 2022
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities in unrealized loss position	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

The following tables summarize the Company’s debt securities in an unrealized loss position, aggregated by length of time in a continuous unrealized loss position.


	December 31, 2022
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)


	December 31, 2021
	Less than 12 Months					More than 12 Months				Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss		Fair Market Value		Unrealized Loss
Short-term marketable securities	$	32,991	$	(29	)	$	—	$	—	$	32,991	$	(29	)
Long-term marketable securities		11,719		(45	)		—		—		11,719		(45	)

	$	44,710	$	(74	)	$	—	$	—	$	44,710	$	(74	)

- Definition

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

+ Details

Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net loss	$ (19,543)	$ (23,386)	$ (81,580)	$ (84,686)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	3,431	5,266	19,831	21,750
Depreciation expense	1,000	726	2,766	2,775
Non-cash lease expense	630	593	2,370	1,066
Non-cash interest expense			396	347
Loss on disposal of assets			0	16
Non-cash interest (income) expense	(112)	266
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	2,051	1,385	681	(173)
Accounts payable	(697)	(429)	(677)	(2,292)
Deferred revenue			0	(14,068)
Lease liabilities	(479)	(412)	(1,816)	(396)
Accrued expenses	(413)	(1,352)	(208)	(398)
Net cash used in operating activities	(14,132)	(17,343)	(58,237)	(76,059)
Cash flows from investing activities:
Sale of property and equipment	7	0	17	0
Purchase of property and equipment	(100)	(12)	0	(2,914)
Purchase of marketable securities	(1,978)	(20,786)	(54,222)	(92,445)
Redemption of marketable securities	7,570	8,136	85,338	29,233
Net cash provided by (used in) investing activities	5,499	(12,662)	31,133	(66,126)
Cash flows from financing activities:
Proceeds from issuance of common stock, net	1	61	60	1,298
Proceeds from Employee Stock Purchase Plan	31	139	196	60
Repayment of Term Loan	(2,500)	0	(833)	0
Net cash (used in) provided by financing activities	(2,468)	200	(577)	1,358
Net decrease in cash, cash equivalents and restricted cash	(11,101)	(29,805)	(27,681)	(140,827)
Cash, cash equivalents, and restricted cash at beginning of period	53,653	81,334	81,334	222,161
Cash, cash equivalents, and restricted cash at end of period	$ 42,552	$ 51,529	53,653	81,334
Supplemental disclosures:
Cash paid for interest			$ 914	$ 703

Restructuring - Schdule of Changes to the liability for the restructuring (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructing liabilities Ending	$ 3,458
Accelerated FX-322 charges
Restructuring Cost and Reserve [Line Items]
Liability balance Opening	0
Net charges	129
Restructing liabilities Ending	129
Accelerated FX-345 charges
Restructuring Cost and Reserve [Line Items]
Liability balance Opening	0
Net charges	3,458
Severance and other benefit-related costs
Restructuring Cost and Reserve [Line Items]
Liability balance Opening	0
Net charges	3,329
Restructing liabilities Ending	$ 3,329

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References + Details

Summary of Significant Accounting Policies - Schedule of Basic And Diluted Net Loss per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net loss	$ (19,543)	$ (23,386)	$ (81,580)	$ (84,686)
Denominator:
Weighted-average shares of common stock outstanding-basic and diluted	$ 35,324,053	$ 34,810,676	$ 35,075,924	$ 34,351,274
Net loss per share attributable to common stockholders-basic and diluted	$ (0.55)	$ (0.67)	$ (2.33)	$ (2.47)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(g)(1)(ii))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481687/323-10-50-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Schedule of Reconciliation Pre-tax Income

A reconciliation of the Company’s

pre-tax

loss for the years ended December 31, 2022 and 2021 is as follows:


	2022			2021
Domestic	$	(81,586	)	$	(84,624	)
Foreign		4			(47	)

Total	$	(81,582	)	$	(84,671	)

Schedule of Provision

The Company’s provision at December 31, 2022 and 2021 consist of the following:


	2022			2021
Current:
Federal	$	—		$	—
State		(2	)		15
Foreign		—			—

Total current	$	(2	)	$	15
Deferred:
Federal		—			—
State		—			—
Foreign		—			—

Total deferred	$	—		$	—

Total (benefit) provision	$	(2	)	$	15

Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate for the years ended December 31, 2022 and 2021 is as follows:


	2022			2021
U.S federal statutory income tax rate		21.0	%		21.0	%
Permanent differences		(0.1	)		—
State income taxes, net of federal benefit		5.4			2.7
Research and development tax credits		5.1			3.6
State rate changes		3.7			—
Stock compensation deductions		(2.8	)		1.6
Other items		—			(0.7	)
Change in deferred tax asset valuation allowance		(32.3	)		(28.2	)

Effective income tax rate		—	%		—	%

Schedule of Deferred Tax Assets

The Company’s deferred tax assets at December 31, 2022 and 2021 consist of the following:


	2022			2021
Deferred tax assets:
Net operating loss carryforwards	$	45,512		$	36,590
Research and development tax credits		11,163			7,026
Capitalized research and development costs		10,042			—
Intangibles		478			392
Stock compensation		9,507			6,554
Accrued expenses		—			107
Deferred revenue		—			—
Other		357			176
Fixed assets		282			265
Lease liability		7,735			7,269

Gross deferred tax asset		85,076			58,379
Valuation allowance		(77,288	)		(50,931	)

Net deferred tax assets	$	7,788		$	7,448
Deferred tax liabilities:
Right of use asset		(7,788	)		(7,448	)

Net deferred tax asset (liability)	$	—		$	—

Net Loss Per Share - Computation of Diluted Net Loss per Share Attributable to Common Stockholders (Details) - shares	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	9,242,253	8,776,013
Unvested Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	3,642,165	2,165,350
Outstanding Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	5,600,088	6,610,663

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2022
Related Party Transactions [Abstract]
Related Party Transactions	18. Related party transactions As disclosed in Note 12, “ Research and license agreements ”, the Company entered into the MIT License Agreement in December 2016. The patents in-licensed by the Company from MIT pursuant to the MIT License Agreement claim inventions created by, among others, Dr. Langer, one of the Company’s directors. Accordingly, Dr. Langer has received $11 and $6 from MIT under the MIT Policy during the years ended December 31, 2022 and 2021, respectively. The Company’s lease for its Woburn, Massachusetts facility, terminated in May 2021 as disclosed in Note 14, “ Leases ”, was with an entity affiliated with one of the Company’s directors and shareholders.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-URI https://asc.fasb.org//1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org//850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
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+ Details

Organization and Basis of Presentation (Policies)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Accounting Policies [Abstract]

Basis of Presentation

Basis of presentation

Accounting Standards

Codification (ASC).

Principles of Consolidation

Principles of consolidation

The consolidated financial statements include the accounts of Frequency Therapeutics, Inc. and its wholly owned subsidiaries Frequency Therapeutics Securities Corporation and Frequency Therapeutics PTY, LTD. All intercompany transactions and balances have been eliminated. The significant accounting policies used in preparation of these interim financial statements are consistent with those discussed in Note 2, “

Summary of significant accounting policies

,” in the Company’s Annual Report on Form

10-K

(the Company’s Form

10-K).

Principles of consolidation

Use of estimates

non-owner

Segment information

Foreign currency

Cash and Cash Equivalents

Cash and cash equivalents

Restricted Cash

Restricted cash

The Company has $1,699 of restricted cash as of December 31, 2022 and December 31, 2021, which represents a security deposit on the Company’s Lexington, Massachusetts facility.

Marketable Securities

Marketable securities

Marketable securities represent holdings of

available-for-sale

Concentration of Credit Risk and Off-balance Sheet Risk

Concentration of credit risk and

off-balance

sheet risk

The Company has no significant

off-balance

sheet arrangements such as foreign exchange contracts, option contracts, or other foreign hedging arrangements.

Significant Suppliers

Significant suppliers

Fair Value Measurements

Fair value measurements

Fair value is defined as the price that would be received upon sale of an asset or paid to transfer a liability between market participants at measurement dates. ASC Topic 820,

Fair Value Measurement

Level 1

Quoted prices in active markets for identical assets or liabilities.

Level 2

Inputs other than quoted prices included within Level 1 that are either directly or indirectly observable, such as quoted market prices, interest rates and yield curves.

Level 3

Unobservable inputs developed using estimates or assumptions developed by the Company, which reflect those that a market participant would use in pricing the asset or liability.

Property and Equipment, Net

Property and equipment, net


	Estimated useful life
Lab equipment		3 years
Software		3 years
Furniture and office equipment		3 years

Impairment of Long-Lived Assets

Impairment of long-lived assets

Research and Development Costs and Accruals

Research and development costs and accruals

in-process

research and development if the technology licensed has not reached technological feasibility and has no alternative future use.

Leases

The Company accounts for leases under ASC 842,

Leases

. The Company determines if an arrangement is, or contains, a lease at inception and, if so, records a

right-of-use

(ROU) asset and a lease liability on the consolidated balance sheet for any lease with a term longer than 12 months.

For real estate lease agreements entered into or modified after the adoption of ASC 842 that include lease and

non-lease

components, the Company has elected to account for the lease and

non-lease

components, such as common area maintenance charges, as a single lease component.

Collaborative Arrangements

Collaborative arrangements

The Company analyzes its collaborative arrangements to assess whether they are within the scope of ASC 808,

Collaborative Arrangements

Revenue from Contracts with Customers

co-development

or clinical activities, are recorded as a reduction to research and development expense as the services are performed. Similarly, amounts that are owed to a collaboration partner related to the

co-development

clinical activities are recognized as research and development expense.

The Company enters into

out-licensing

agreements that are within the scope of ASC 606. The terms of such

out-license

non-refundable

up-front

license fees; reimbursement of certain costs; development and regulatory milestone payments and milestone payments based on the level of sales; and royalties on net sales of licensed products.

The Company has entered into a collaboration arrangement with Astellas Pharma Inc. (Astellas), as further described in Note 13, “

Collaboration agreement

”, of notes to consolidated financial statements.

Revenue Recognition

Revenue recognition

know-how,

research and development activities, and/or manufacturing services.

re-evaluates

catch-up

basis in the period of adjustment.

re-evaluates

the probability of achievement of all milestones subject to constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative

catch-up

basis, which would affect revenues and earnings in the period of adjustment.

Patent Costs

Patent costs

The Company expenses patent application and related legal costs as incurred and classifies such costs as general and administrative expenses in the accompanying consolidated statements of operations.

Stock-Based Compensation

Stock-based compensation

The Company accounts for its stock-based compensation in accordance with ASC Topic 718,

Compensation—Stock Compensation

2016-09

which identifies areas for simplification of several areas of share-based payment transactions. The Company treats

non-employee

grants in a manner consistent with employee grants. The Company estimates the fair value of options granted using the Black-Scholes option pricing model for stock option grants to both employees and

non-employees.

The Company believes the fair value of the stock options granted to

non-employees

is more reliably determinable than the fair value of the services provided.

non-employees,

The Company expenses the fair value of its share-based compensation awards to employees and

non-employees

on a straight-line basis over the requisite service period, which is generally the vesting period.

Income Taxes

Income taxes

The Company accounts for income taxes using the asset and liability method in accordance with ASC Topic 740,

Income Taxes

“

Income taxes

”).

Net Loss Per Share

Net loss per share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Year Ended December 31,
	2022			2021
Numerator:
Net loss	$	(81,580	)	$	(84,686	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,075,924			34,351,274

Net loss per share-basic and diluted	$	(2.33	)	$	(2.47	)

Unaudited interim financial information

The accompanying consolidated balance sheet as of March 31, 2023 and the consolidated statements of operations, the consolidated statements of comprehensive loss, the consolidated statements of stockholders’ equity and the consolidated statements of cash flows for the three months ended March 31, 2023 and 2022 are unaudited. The unaudited interim consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments,

which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2023, the results of its operations for the three months ended March 31, 2023 and 2022, and cash flows for the three months ended March 31, 2023 and 2022. The financial data and other information disclosed in these notes related to the three months ended March 31, 2023 and 2022 are also unaudited. The results for the three months ended March 31, 2023 are not necessarily indicative of results to be expected for the year ending December 31, 2023, any other interim periods, or any future year or period. The consolidated balance sheet as of December 31, 2022 included herein was derived from the audited consolidated financial statements as of that date.

These unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2022 included in the Company’s Form

10-K.

Recently adopted and issued accounting standards

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. The Company is an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012, as amended (the JOBS Act). The JOBS Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. Thus, an emerging growth company can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company elected to avail itself of this extended transition period and, as a result, the Company will not be required to adopt new or revised accounting standards on the relevant dates on which adoption of such standards is required for other public companies.

In June 2016, the FASB issued ASU

No. 2016-13,

Financial Instruments—Credit Losses

(Topic 326): Measurement of Credit Losses on Financial Instruments. The FASB has subsequently issued amendments to ASU

2016-13,

available-for-sale

debt securities to the amount by which carrying value exceeds fair value and requires the reversal of previously recognized credit losses if fair value increases. The Company adopted the standard on January 1, 2023 and it did not have a material impact on the consolidated financial statements.

Recently issued and adopted accounting pronouncements

In June 2016, the FASB issued ASU

No. 2016-13,

Financial Instruments—Credit Losses

(Topic 326): Measurement of Credit Losses on Financial Instruments. The FASB has subsequently issued amendments to ASU

2016-13,

available-for-sale

Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Dr. Langer
Related Party Transaction [Line Items]
Payment to director	$ 11	$ 6

Consolidated Statements Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional-paid in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning Balance at Dec. 31, 2020	$ 192,491	$ 34	$ 287,829	$ 27	$ (95,399)
Beginning Balance (in shares) at Dec. 31, 2020		33,964,000
Stock-based compensation expense	21,750		21,750
Purchase of common stock under Employee Stock Purchase Plan	60		60
Purchase of common stock under Employee Stock Purchase Plan (in shares)		7,064
Issuance of common stock, net	1,298	$ 1	1,297
Issuance of common stock, net (in shares)		642,314
Forfeiture of restricted stock (in shares)		(2,165)
Other comprehensive loss	(89)			(89)
Net loss	(84,686)				(84,686)
Ending Balance at Dec. 31, 2021	$ 130,824	$ 35	310,936	(62)	(180,085)
Ending Balance (in shares) at Dec. 31, 2021	34,611,213	34,611,213
Stock-based compensation expense	$ 5,266		5,266
Purchase of common stock under Employee Stock Purchase Plan	139		139
Purchase of common stock under Employee Stock Purchase Plan (in shares)		31,832
Issuance of common stock, net	61		61
Issuance of common stock, net (in shares)		22,764
Issuance of common stock pursuant to restricted stock units (Shares)		310,600
Other comprehensive loss	(234)			(234)
Net loss	(23,386)				(23,386)
Ending Balance at Mar. 31, 2022	112,670	$ 35	316,402	(296)	(203,471)
Ending Balance (in shares) at Mar. 31, 2022		34,976,409
Beginning Balance at Dec. 31, 2021	$ 130,824	$ 35	310,936	(62)	(180,085)
Beginning Balance (in shares) at Dec. 31, 2021	34,611,213	34,611,213
Stock-based compensation expense	$ 19,831		19,831
Purchase of common stock under Employee Stock Purchase Plan	196		196
Purchase of common stock under Employee Stock Purchase Plan (in shares)		76,606
Issuance of common stock, net	11		11
Issuance of common stock, net (in shares)		10,047
Issuance of common stock under equity offering (in shares)		12,767
Issuance of common stock under equity offering	50		50
Issuance of common stock pursuant to restricted stock units (Shares)		551,450
Issuance Of Common Stock Pursuant To Restricted Stock Units	(1)		(1)
Other comprehensive loss	(136)			(136)
Net loss	(81,580)				(81,580)
Ending Balance at Dec. 31, 2022	$ 69,195	$ 35	331,023	(198)	(261,665)
Ending Balance (in shares) at Dec. 31, 2022	35,262,083	35,262,083
Stock-based compensation expense	$ 3,431		3,431
Purchase of common stock under Employee Stock Purchase Plan	31		31
Purchase of common stock under Employee Stock Purchase Plan (in shares)		24,754
Issuance of common stock, net (in shares)		2,969
Issuance of common stock pursuant to restricted stock units (Shares)		462,150
Issuance Of Common Stock Pursuant To Restricted Stock Units	1	$ 1
Other comprehensive loss	134			(134)
Net loss	(19,543)				(19,543)
Ending Balance at Mar. 31, 2023	$ 53,249	$ 36	$ 334,485	$ (64)	$ (281,208)
Ending Balance (in shares) at Mar. 31, 2023	35,751,956	35,751,956

Prepaid Expenses and Other Current Assets

12 Months Ended

Dec. 31, 2022

Prepaid Expense and Other Assets, Current [Abstract]

Prepaid Expenses and Other Current Assets

4. Prepaid expenses and other current assets

Prepaid expenses and other current assets consisted of the following:


	December 31, 2022		December 31, 2021
Rent and deposits	$	—	$	470
Research and development expenses		2,084		858
Accounts receivable		449		144
Insurance		1,608		2,384
Other		255		185

Total	$	4,396	$	4,041

Employee Benefit Plan	12 Months Ended
Employee Benefit Plan	Dec. 31, 2022
Retirement Benefits [Abstract]
Employee Benefit Plan	17. Employee benefit plan Employees of the Company are eligible to participate in the Company’s 401(k) retirement plan (401(k) Plan). Partic ipan ts may contribute up to 90% of their annual compensation to the 401(k) Plan, subject to statutory limitations. Under the 401(k) Plan Safe Harbor Match, the Company matches 100% of the first 5% of employee contributions and vests 100% at time of match. For the years ended December 31, 2022 and 2021, the Company made matching contributions of $550 and $723, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480794/715-70-50-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iv)(03)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (q)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (l)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//715/tableOfContent

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)(iii)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (o)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (p)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (r)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480126/715-20-S99-2

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 60
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480266/715-60-50-3

+ Details

Income Taxes - Schedule of Provision (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended		111 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2023
Current:
Federal			$ 0	$ 0
State			(2)	15
Foreign			0	0
Total current			(2)	15
Deferred:
Federal			0	0
State			0	0
Foreign			0	0
Total Deferred			0	0
Total (benefit) provision	$ 24	$ 12	$ (2)	$ 15	$ 0

Organization and Basis of Presentation - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended	12 Months Ended
	Feb. 13, 2023	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Subsidiary Sale Of Stock [Line Items]
Date of incorporation		Nov. 30, 2014	Nov. 30, 2014
Accumulated deficit		$ 281,208	$ 261,665	$ 180,085
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent	55.00%

- Definition

Amount of accumulated undistributed earnings (deficit).

+ References + Details

Leases - Schedule of Future Aggregate Minimum Payments (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Leases [Abstract]
2023	$ 4,273
2024	4,402
2025	4,534
2026	4,670
2027 and beyond	22,340
Total minimum lease payments	$ 40,219

Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Total	$ 9,276	$ 9,235	$ 9,706
Accumulated depreciation	(7,444)	(6,496)	(4,184)
Property and equipment, net	1,832	2,739	5,522
Lab equipment
Property Plant And Equipment [Line Items]
Total	5,747	5,706	6,177
Furniture and office equipment
Property Plant And Equipment [Line Items]
Total	3,238	3,238	3,238
Software
Property Plant And Equipment [Line Items]
Total	$ 291	$ 291	$ 291

Accrued Expenses

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Payables and Accruals [Abstract]

Accrued Expenses

6. Accrued expenses

Accrued expenses consist of the following:


	March 31, 2023		December 31, 2022
Payroll and employee related expenses	$	3,831	$	4,216
Professional fees		550		377
Third-party research and development expenses		457		773
Other		729		525

Total	$	5,567	$	5,891

6. Accrued expenses

Accrued expenses consist of the following:


	December 31, 2022		December 31, 2021
Payroll and employee related expenses	$	4,216	$	4,375
Professional fees		377		767
Third-party research and development expenses		773		840
Other		525		119

Total	$	5,891	$	6,101

Investments - Schedule of debt securities in an unrealized loss position (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Market Value, Less than 12 Months	$ 8,407	$ 17,303	$ 44,710
Unrealized Loss, Less than 12 Months	(21)	(78)	(74)
Fair Market Value, More than 12 Months	9,943	9,927	0
Unrealized Loss, More than 12 Months	(54)	(135)	0
Fair Market Value	18,350	27,230	44,710
Unrealized Loss	(75)	(213)	(74)
Short Term Marketable Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Market Value, Less than 12 Months	8,407	17,303	32,991
Unrealized Loss, Less than 12 Months	(21)	(78)	(29)
Fair Market Value, More than 12 Months	9,943	9,927	0
Unrealized Loss, More than 12 Months	(54)	(135)	0
Fair Market Value	18,350	27,230	32,991
Unrealized Loss	$ (75)	$ (213)	$ (29)

Collaboration Agreement	3 Months Ended	12 Months Ended
Collaboration Agreement	Mar. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Collaboration Agreement	13. Collaboration agreement In July 2019, the Company entered into a License and Collaboration Agreement with Astellas (the Astellas Agreement), under which the Company granted Astellas an exclusive, royalty-bearing, sub-licensable, nontransferable license to certain patent rights to research, develop, manufacture, have manufactured, use, seek and secure regulatory approval for, commercialize, offer for sale, sell, have sold and import, and otherwise exploit licensed products containing both a GSK-3 inhibitor and an HDAC inhibitor, (the Astellas Licensed Products), including the product candidate FX-322, outside of the United States. The Company also granted Astellas a right of first negotiation and a right of last refusal if it entered into any negotiation or agreement of any kind (other than an acquisition of all of the stock or assets of the Company) with any third party under which such third party would obtain the right to develop, manufacture, or commercialize Astellas Licensed Products in the United States. As consideration for the licensed rights under the Astellas Agreement, Astellas paid the Company an upfront payment of $80,000 in July 2019 and has agreed to pay potential development milestone payments up to $230,000 and commercialization milestones of up to $315,000. The parties agreed to share equally, on a 50/50 basis, all out-of-pocket costs and joint study costs for all the joint activities conducted pursuant to the development plans or the joint manufacturing plan. On April 11, 2023, Astellas sent the Company a notice stating that Astellas would be terminating the Astellas Agreement in its entirety on April 14, 2023. The Company agreed to the terms of the notice and on April 14, 2023, the Astellas Agreement was terminated in its entirety. The Company was not subject to any payments or costs as a result of this termination. The Astellas Agreement was a collaborative agreement that is within the scope of ASC 808, Collaborative Arrangements. Under the provisions of ASC 808, the Company determined that it would apply the guidance in ASC 606 to recognize the revenue related to the license since that component of the arrangement is more reflective of a vendor-customer relationship. The Company recognized the $80,000 upfront fee, which was initially recorded as deferred revenue, as revenue over the period from July 2019 until June 30, 2021, when the Phase 2a clinical trial (FX-322-202), the Company’s performance obligation, was completed. The Astellas Agreement contains joint research and development activities that are not within the scope of ASC 606. The Company invoices Astellas for all joint costs. In the three months ended March 31, 2023 and 2022, the Company invoiced Astellas $14 and $193, respectively, for joint costs.	13. Collaboration agreement In July 2019, the Company entered into a License and Collaboration Agreement with Astellas (Astellas Agreement), under which the Company granted Astellas an exclusive, royalty-bearing, sub-licensable, nontransferable license to certain patent rights to research, develop, manufacture, have manufactured, use, seek and secure regulatory approval for, commercialize, offer for sale, sell, have sold and import, and otherwise exploit licensed products containing both a GSK-3 inhibitor and an HDAC inhibitor (Astellas Licensed Products), including the product candidate FX-322, outside of the United States. The Company also granted Astellas a right of first negotiation and a right of last refusal if it entered into any negotiation or agreement of any kind (other than an acquisition of all of the stock or assets of the Company) with any third party under which such third party would obtain the right to develop, manufacture, or commercialize Astellas Licensed Products in the United States. These parties have agreed to use commercially reasonable efforts to carry out development activities assigned to it under an agreed-upon development plan. Astellas has agreed to use commercially reasonable efforts to obtain regulatory approval for at least one Astellas Licensed Product in sensorineural hearing loss and in age-related hearing loss, in each case, in one major Asian country and one major European country. The Company has agreed to use commercially reasonable efforts to obtain regulatory approval for at least one Astellas Licensed Product in the United States. Astellas has the sole right to commercialize the Astellas Licensed Products outside of the United States, and the Company has the sole right to commercialize the Astellas Licensed Products in the United States. Astellas has agreed to use commercially reasonable efforts to commercialize Astellas Licensed Products in a major Asian country and a major European country following receipt of regulatory approval in such countries. The collaboration is governed by a joint steering committee (JSC) established under the Astellas Agreement and shall be comprised of three representatives each from the Company and Astellas. The JSC shall oversee and coordinate the overall conduct of the development, manufacture and commercialization of the Astellas Licensed Products. All decisions of JSC shall be taken through a unanimous vote with each party’s representatives collectively having one vote. Both the parties shall be responsible for carrying out the development and manufacturing activities in their defined territory in accordance with the plan as reviewed and approved in the JSC. As consideration for the licensed rights under the Astellas Agreement, Astellas paid the Company an upfront payment of $80,000 in July 2019 and has agreed to pay potential development milestone payments up to $230,000 and commercialization milestones of up to $315,000. Specifically, the Company would receive development milestone payments of $65,000 and $25,000 upon the first dosing of a subject in a Phase 2b clinical trial for SNHL in Europe and Asia, respectively and $100,000 and $40,000 upon the first dosing of a subject in a Phase 3 clinical trial for SNHL in Europe and Asia, respectively. If the Astellas Licensed Products are successfully commercialized, the Company would be eligible for up to $315,000 in potential commercial milestone payments and also tiered royalties at rates ranging from low- to mid-teen percentages. The parties shall share equally, on a 50/50 basis, all out-of-pocket costs and joint study costs for all the joint activities conducted pursuant to the development plans or the joint manufacturing plan. The Astellas Agreement remains in effect until the expiration of all royalty obligations. Royalties are paid on a licensed product-by-licensed product and country-by-country basis until the latest of (i) the expiration of the last valid claim in the licensed patent rights with respect to such Astellas Licensed Product in such country or (ii) a set number of years from the first commercial sale of such Astellas Licensed Product in such country. Astellas may terminate the Astellas Agreement at will upon 60 days’ written notice. Each party has the right to terminate the Astellas Agreement due to the other party’s material breach if such breach remains uncured for 90 days (or 45 days in the case of nonpayment) or if the other party becomes bankrupt. The Astellas Agreement is a collaborative agreement that is within the scope of ASC 808. The Company analyzed the joint research and development activities to assess whether they fall within the scope of ASC 808, and will reassess this throughout the life of the arrangement based on changes in the roles and responsibilities of the parties. Based on the terms of the arrangement as outlined above, both parties are deemed to be active participants in the collaboration. Both parties are performing research and development activities in their defined territory and will be performing joint clinical studies in accordance with the development plan and the study protocol approved by the JSC. Additionally, Astellas and the Company are exposed to significant risks and rewards dependent on the commercial success of any product candidates that may result from the collaboration. As such, the collaboration arrangement is deemed to be within the scope of ASC 808. The arrangement consists of two components; the license of IP and the research and development activities, including committee participation, to support the co-development and research plan. Under the provisions of ASC 808, the Company has determined that it will apply the guidance in ASC 606 to recognize the revenue related to the license since that component of the arrangement is more reflective of a vendor-customer relationship. The Company determined that the license and the related research and development services associated with the Phase 2a clinical study were not distinct from one another, as the license has limited value to Astellas without the performance of the research and development activities and the Phase 2a study is essential to the use of the license. As such, the Company determined that these activities should be accounted for as a single combined performance obligation. Revenue associated with this single performance obligation was recognized as the research and development work was performed, using an input method on the basis of research and development costs incurred to date relative to total research and development costs expected to be incurred. The transfer of control occurred over this time period and, in management’s judgment, was the best measure of progress towards satisfying the performance obligation. The Company determined that the period of performance of the research and development services began upon the signing of the Astellas Agreement and continued until the completion of the Phase 2a clinical trial of FX-322 (FX-322-202). The transaction price of $80,000 was allocated to the single combined performance obligation and recorded as deferred revenue in July 2019 when it was received. This upfront payment was recognized as revenue over the period from July 2019 until June 30, 2021, the completion date of the Phase 2a clinical trial (FX-322-202), using the input method. The potential development and regulatory milestone payments are fully constrained until the Company can conclude that achievement of the milestone is probable and that it is probable that recognition of revenue related to the milestone will not result in a significant reversal in the amount of cumulative revenue recognized when the uncertainty associated with the variable consideration is ultimately resolved and as such these have been excluded from the transaction price. As part of its evaluation of the constraint, the Company considers numerous factors, including the fact that achievement of the milestones is outside the control of the Company and contingent upon the future success of clinical trials, the licensee’s efforts, and the receipt of regulatory approval. Any consideration related to sales-based milestones (including royalties) will be recognized when the related sales occur as these amounts have been determined to relate predominantly to the license granted to Astellas and therefore are recognized at the later of when the performance obligation is satisfied, or the related sales of licensed products occur. The Company re-evaluates the transaction price, including its estimated variable consideration included in the transaction price and all constrained amounts, at each reporting period and as uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect revenues and earnings in the period of adjustment. The Astellas Agreement contains joint research and development activities that are not within the scope of ASC 606. The Company will recognize research and development expense related to the joint study costs for all the joint activities in future periods and reimbursements received from Astellas will be recognized as an offset to research and development expense on the consolidated statements of operations during the development period. In the year ended December 31, 2022 and 2021, the Company invoiced Astellas $392 and $885 for joint costs.

Stockholders' Equity - Schedule of Common Stock Shares Reserved for Future Issuance (Details) - shares	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Class Of Stock [Line Items]
Shares of common stock reserved for future issuance	7,290,493	6,730,269	8,382,667
Stock Options Outstanding
Class Of Stock [Line Items]
Shares of common stock reserved for future issuance	5,600,088	5,742,053	6,830,037
Shares Available for Future Grant Under Stock Option Plan
Class Of Stock [Line Items]
Shares of common stock reserved for future issuance	1,690,405	988,216	1,552,630

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 272
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-Name Accounting Standards Codification
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-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483014/272-10-45-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-Paragraph 1
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-14

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
-Paragraph 18
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
-Subparagraph (SX 210.5-02(27)(b))
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-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
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-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Section 50
-Paragraph 2
-Publisher FASB
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
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-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(2))
-Publisher FASB
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 3
-Subparagraph (SX 210.6-03(i)(1))
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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+ Details

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Assets (Details)	Dec. 31, 2022
Lab equipment
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Software
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years
Furniture and office equipment
Summary Of Significant Accounting Policies [Line Items]
Property and equipment, estimated useful lives	3 years

Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Revenue			$ 0	$ 14,068
Operating expenses:
Research and development	$ 11,355	$ 13,781	49,418	60,923
General and administrative	9,156	9,477	33,584	37,176
Total operating expenses	20,511	23,258	83,002	98,099
Loss from operations	(20,511)	(23,258)	(83,002)	(84,031)
Interest income	523	95	1,327	397
Interest expense	(284)	(178)	(961)	(764)
Realized gain (loss) on investments			3	(23)
Foreign exchange (loss) gain			(5)	16
Other income (expense), net	753	(33)	1,056	(266)
Loss before income taxes	(19,519)	(23,374)	(81,582)	(84,671)
Income tax benefit (provision)	(24)	(12)	2	(15)
Net loss	$ (19,543)	$ (23,386)	$ (81,580)	$ (84,686)
Net loss per share attributable to common stockholders-basic and diluted	$ (0.55)	$ (0.67)	$ (2.33)	$ (2.47)
Weighteds Average Number Of Share Outstanding Basic And Diluted	$ 35,324,053	$ 34,810,676	$ 35,075,924	$ 34,351,274

Employee Benefit Plan - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Maximum percentage of employee contribution to retirement plan	90.00%
Percentage of employer matching contribution	100.00%
Percentage of employee annual compensation matched by the employer	5.00%
Employers matching contribution vesting percentage	100.00%
Employers matching contribution	$ 550	$ 723

Income Taxes - Schedule of Reconciliation Pre-tax Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Domestic	$ (81,586)	$ (84,624)
Foreign	4	(47)
Total	$ (81,582)	$ (84,671)

Organization and Basis of Presentation	3 Months Ended	12 Months Ended
Organization and Basis of Presentation	Mar. 31, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Basis of Presentation	1. Organization and basis of presentation Organization Frequency Therapeutics, Inc., together with its wholly owned subsidiaries, Frequency Therapeutics, PTY, LTD, and Frequency Therapeutics Securities Corporation (the Company) headquartered in Lexington, Massachusetts, was incorporated in November 2014 as a Delaware corporation. The Company is a preclinical-stage regenerative medicine company focused on developing therapeutics to activate a person’s innate regenerative potential to restore function. On February 13, 2023, the Company announced a restructuring of the business which included the discontinuation of its hearing program and a downsizing of personnel by approximately 55%. Liquidity and capital resources The Company has funded its operations primarily with proceeds from private and public securities financings, a term loan, and amounts received under a collaboration agreement. The Company has incurred recurring losses since its inception. In addition, as of March 31, 2023, the Company had an accumulated deficit of $281,208. The Company expects to continue to generate operating losses for the foreseeable future. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. The Company’s inability to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies. There can be no assurances that additional funding will be available on terms acceptable to the Company, or at all. The Company believes that existing resources and the cost savings generated from the restructuring announced in February 2023 will be sufficient to fund planned operations for at least twelve months from the date the financial statements were available to be issued. Basis of presentation The accompanying consolidated financial statements have been prepared in accordance with accounting standards set by the Financial Accounting Standards Board (FASB). The FASB sets generally accepted accounting principles (GAAP) that the Company follows to ensure its financial condition, results of operations, and cash flows are consistently reported. References to GAAP issued by the FASB in these notes to the consolidated financial statements are to the FASB Accounting Standards Codification (ASC). Principles of consolidation The consolidated financial statements include the accounts of Frequency Therapeutics, Inc. and its wholly owned subsidiaries Frequency Therapeutics Securities Corporation and Frequency Therapeutics PTY, LTD. All intercompany transactions and balances have been eliminated. The significant accounting policies used in preparation of these interim financial statements are consistent with those discussed in Note 2, “ Summary of significant accounting policies ,” in the Company’s Annual Report on Form 10-K (the Company’s Form 10-K). Unaudited interim financial information The accompanying consolidated balance sheet as of March 31, 2023 and the consolidated statements of operations, the consolidated statements of comprehensive loss, the consolidated statements of stockholders’ equity and the consolidated statements of cash flows for the three months ended March 31, 2023 and 2022 are unaudited. The unaudited interim consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of March 31, 2023, the results of its operations for the three months ended March 31, 2023 and 2022, and cash flows for the three months ended March 31, 2023 and 2022. The financial data and other information disclosed in these notes related to the three months ended March 31, 2023 and 2022 are also unaudited. The results for the three months ended March 31, 2023 are not necessarily indicative of results to be expected for the year ending December 31, 2023, any other interim periods, or any future year or period. The consolidated balance sheet as of December 31, 2022 included herein was derived from the audited consolidated financial statements as of that date. These unaudited consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2022 included in the Company’s Form 10-K.	1. Organization Frequency Therapeutics, Inc., together with its wholly owned subsidiaries, Frequency Therapeutics, PTY, LTD, Frequency Therapeutics Securities Corporation and Frequency Therapeutics Japan KK (Frequency Japan) (the Company), headquartered in Lexington, Massachusetts, was incorporated in November 2014 as a Delaware corporation. Frequency Japan was closed down in February 2021. The Company is a preclinical-stage regenerative medicine company focused on developing therapeutics to activate a person’s innate regenerative potential to restore function. Liquidity and capital resources The Company has funded its operations primarily with proceeds from private and public securities financings, a term loan, and amounts received under a collaboration agreement. The Company has incurred recurring losses since its inception. In addition, as of December 31, 2022, the Company had an accumulated deficit of $261,665. The Company expects to continue to generate operating losses for the foreseeable future. The future viability of the Company is dependent on its ability to raise additional capital to finance its operations. The Company’s inability to raise capital as and when needed could have a negative impact on its financial condition and ability to pursue its business strategies. There can be no assurances that additional funding will be available on terms acceptable to the Company, or at all. The Company believes that existing resources will be sufficient to fund planned operations for at least 12 months from the date the financial statements were available to be issued.

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment include the following:


	December 31, 2022			December 31, 2021
Lab equipment	$	5,706		$	6,177
Furniture and office equipment		3,238			3,238
Software		291			291

Total		9,235			9,706
Accumulated depreciation		(6,496	)		(4,184	)

Property and equipment, net	$	2,739		$	5,522

Recently Adopted And Issued Accounting Standards	3 Months Ended
Recently Adopted And Issued Accounting Standards	Mar. 31, 2023
Accounting Policies [Abstract]
Recently Adopted and Issued Accounting Standards	2. Recently adopted and issued accounting standards From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by the Company as of the specified effective date. The Company is an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012, as amended (the JOBS Act). The JOBS Act provides that an emerging growth company can take advantage of an extended transition period for complying with new or revised accounting standards. Thus, an emerging growth company can delay the adoption of certain accounting standards until those standards would otherwise apply to private companies. The Company elected to avail itself of this extended transition period and, as a result, the Company will not be required to adopt new or revised accounting standards on the relevant dates on which adoption of such standards is required for other public companies. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The FASB has subsequently issued amendments to ASU 2016-13, which have the same effective date and transition date. These standards require that credit losses be reported using an expected losses model rather than the incurred losses model that was previously used, and establishes additional disclosures related to credit risks. For available-for-sale debt securities with unrealized losses, this standard now requires allowances to be recorded instead of reducing the amortized cost of the investment. These standards limit the amount of credit losses to be recognized for available-for-sale debt securities to the amount by which carrying value exceeds fair value and requires the reversal of previously recognized credit losses if fair value increases. The Company adopted the standard on January 1, 2023 and it did not have a material impact on the consolidated financial statements.

- Definition

The entire disclosure for change in accounting principle. Includes, but is not limited to, nature, reason, and method of adopting amendment to accounting standards or other change in accounting principle.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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-Section 65
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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Reference 23: http://www.xbrl.org/2003/role/disclosureRef
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Reference 24: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Subsequent Events (Additional Information) (Details) - USD ($) $ in Thousands	Feb. 13, 2023	Apr. 03, 2023	Dec. 11, 2020
Subsequent Event [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent	55.00%
Loan Agreement
Subsequent Event [Line Items]
Debt instrument final payment			$ 150
Subsequent Event [Member]
Subsequent Event [Line Items]
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent	55.00%
Restructuring Costs	$ 4,000
Subsequent Event [Member] \| Term Loan
Subsequent Event [Line Items]
Debt Due		$ 11,667
Subsequent Event [Member] \| Loan Agreement
Subsequent Event [Line Items]
Debt instrument final payment		$ 150

Sublease

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Sublease

15. Sublease

On July 8, 2022, the Company entered into a Sublease Agreement with SalioGen Therapeutics, Inc. (SalioGen) to sublease approximately 30,040 rentable square feet of the Company’s office space in Lexington, MA for a

two-year

term. The base sublease rent per month for the first and second year of the sublease is $197 and $203, respectively. In addition to base rent, SalioGen will pay 49% of operating costs and taxes payable under the Company’s lease for the Lexington, MA office space.

Since commencement, the Company has accounted for the Lexington, MA office space as an operating lease. In accordance with ASC 842, the Company concluded the sublease is also an operating lease. The Company recognized sublease income of $1,186 for the year ended December 31, 2022. The below table shows the expected future sublease income as of December 31, 2022.


Years Ending December 31,	Sublease Income
2023	$	2,371
2024		1,383

Total future sublease income	$	3,754

Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Prepaid Expense and Other Assets, Current [Abstract]
Rent and deposits		$ 0	$ 470
Research and development expenses		2,084	858
Accounts receivable		449	144
Insurance		1,608	2,384
Other		255	185
Total	$ 2,643	$ 4,396	$ 4,041

Net Loss Per Share

3 Months Ended

Mar. 31, 2023

Earnings Per Share [Abstract]

Net Loss Per Share

8. Net loss per share

Basic net loss per share is computed by dividing net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share is computed using the weighted-average number of shares of common stock outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. Diluted net loss per share is the same as basic net loss per share for the three months ended March 31, 2023 and 2022 since all potential shares of common stock instruments are anti-dilutive as a result of the loss for such periods.


	Three Months Ended March 31,
	2023			2022
Numerator:
Net Loss	$	(19,543	)	$	(23,386	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,324,053			34,810,676

Net loss per share attributable to common stockholders-basic and diluted	$	(0.55	)	$	(0.67	)

The Company excluded the following potential shares of common stock from the computation of diluted net loss per share because including them would have had an anti-dilutive effect.


	Three Months Ended March 31,
	2023		2022
Unvested restricted stock units		3,642,165		2,165,350
Outstanding stock options		5,600,088		6,610,663

Total		9,242,253		8,776,013

Investment

3 Months Ended

Mar. 31, 2023

Investments, Debt and Equity Securities [Abstract]

Investment

4. Investments

The following tables summarize the Company’s investments, all of which are classified as

available-for-sale

and recorded at fair value:


	March 31, 2023
	Amortization Cost		Unrealized Loss			Fair Market Value
Short-term marketable securities		25,799		(2	)		25,797

	$	25,799	$	(2	)	$	25,797


	December 31, 2022
	Amortization Cost		Unrealized Loss			Fair Market Value
Short-term marketable securities		31,280		(317	)		31,143

	$	31,280	$	(317	)	$	31,143

The Company’s short-term marketable securities were held in investment advisory accounts with SVB Asset Management (SAM). On March 27, 2023, following the closure of SVB, SAM’s former parent company, and the creation of SVBB, the FDIC entered into a purchase and assumption agreement for certain assets of SVBB with First-Citizens Bank & Trust Company (FCB). As a result of this transaction, SAM became a wholly owned subsidiary of FCB. Although the accounts are held under the terms in place prior to the transaction, the Company is actively working to move these accounts to another financial institution.

The Company determines the appropriate classification of investments at the time of purchase and reviews any investment when its fair value is less than its amortized cost and when evidence indicates that the investment’s carrying amount is not recoverable within a reasonable period of time. The Company evaluates whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, the Company considers the extent to which fair value is less than amortized cost, any changes to the rating of the security by a rating agency, and adverse conditions specifically related to the security, among other factors. If

this assessment indicates that a credit loss may exist, the present value of cash flows expected to be collected from the investment is compared to its amortized cost basis. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded on the consolidated balance sheet, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that is not related to a credit loss is recognized in other comprehensive (loss) income. The unrealized losses at March 31, 2023 and December 31, 2022 were attributable to changes in interest rates and do not represent credit losses.

At March 31, 2023 and December 31, 2022 the Company held 9 and 14 debt securities, respectively, that were in an unrealized loss position. The Company does not intend to sell the investments before recovery of their amortized cost bases, which may be at maturity. All investments mature within twelve months from March 31, 2023. The following tables summarize the Company’s debt securities in an unrealized loss position, aggregated by length of time in a continuous unrealized loss position.


	March 31, 2023
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities in unrealized loss position	$	8,407	$	(21	)	$	9,943	$	(54	)	$	18,350	$	(75	)

	$	8,407	$	(21	)	$	9,943	$	(54	)	$	18,350	$	(75	)


	December 31, 2022
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities in unrealized loss position	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001	$ 0.001
Preferred stock, authorized shares	10,000,000	10,000,000	10,000,000
Preferred stock, issued shares	0	0	0
Preferred stock, outstanding shares	0	0	0
Common stock, par value	$ 0.001	$ 0.001	$ 0.001
Common stock, authorized shares	200,000,000	200,000,000	200,000,000
Common stock, issued shares	35,751,956	35,262,083	34,611,213
Common stock, outstanding shares	35,751,956	35,262,083	34,611,213

Leases

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Leases

14. Leases

On December 11, 2020, the Company entered into an Agreement for Termination of Lease and Voluntary Surrender of Premises (Lease Termination Agreement) with

ARE-MA

Region No. 20, LLC (Landlord) for the Company’s office and laboratory space in Woburn, Massachusetts. The Lease Termination Agreement provides that the Lease Agreement, dated as of August 14, 2016, by and between the Company and Landlord (as the same may have been amended, the Lease) will terminate on March 31, 2021, unless the Company elects to extend the term of the Lease. The Company exercised the option to extend the lease until May 31, 2021.

On January 7, 2020 the Company entered into an indenture of lease (Lexington Lease) with HCP/KING 75 Hayden LLC, for the lease of approximately 61,307 square feet of rentable area in Lexington, Massachusetts or (Lexington Premises). The Lexington Lease commenced on December 11, 2020. In the second quarter of 2021, the Company began using the Lexington Premises as its principal executive offices and laboratory for research and development. The term of the Lexington Lease is expected to end on May 31, 2031. The Company also has the option to extend the Initial Term for two additional terms of five years each.

The Company’s rent expense for the years ended December 31, 2022 and 2021 was $4,802 and $4,960, respectively.


Other information	December 31, 2022
Weighted-average remaining operating lease term		8.4 years
Weighted-average discount rate		8.5	%

The table below reconciles the undiscounted cash flows to the operating lease liability recorded on the consolidated balance sheet as of December 31, 2022.


2023		4,273
2024		4,402
2025		4,534
2026		4,670
2027		4,810
Thereafter		17,530

Total minimum lease payments		40,219
Less: amount of lease payments representing interest		(11,437	)

Present value of future lease payments		28,782
Less: current lease liabilities		(2,021	)

Noncurrent lease liabilities	$	26,761

Future aggregate minimum payments under the noncancelable operating lease as of December 31, 2022 are as follows:


2023	$	4,273
2024		4,402
2025		4,534
2026		4,670
2027 and beyond		22,340

Total minimum lease payments	$	40,219

Income Taxes - Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
U.S federal statutory income tax rate	21.00%	21.00%	21.00%	21.00%
Permanent differences			(0.10%)	0.00%
State income taxes, net of federal benefit			5.40%	2.70%
Research and development tax credits			5.10%	3.60%
State rate changes			3.70%	0.00%
Stock compensation deductions			(2.80%)	1.60%
Other items			0.00%	(0.70%)
Change in deferred tax asset valuation allowance			(32.30%)	(28.20%)
Effective income tax rate			0.00%	0.00%

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended		111 Months Ended
	Dec. 31, 2014	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2023	Oct. 31, 2019	Mar. 31, 2017	Feb. 28, 2017
Income Taxes Disclosure [Line Items]
Net tax benefit		$ 24	$ 12	$ (2)	$ 15	$ 0
Federal and state deferred tax benefits				0	0
Valuation allowance				77,288	50,931
Unrecognized tax benefits				0	0
Interest and penalties				$ 0	$ 0
Statutory rate		21.00%	21.00%	21.00%	21.00%
Internal Revenue Service
Income Taxes Disclosure [Line Items]
Period of cumulative change in ownership				3 years
Operating loss carryforwards, utilization after ownership change								$ 10,800
Operating loss carryforwards, utilization after five years after ownership change								1,600
Operating loss carryforwards, utilization after 15 years thereafter after ownership change								180
Remaining pre ownership change in operating loss carryforwards written off due to expiration								$ 1,600
Internal Revenue Service \| Minimum
Income Taxes Disclosure [Line Items]
Cumulative change in ownership percentage				50.00%
Research and Development
Income Taxes Disclosure [Line Items]
Net tax benefit	$ 0
Massachusetts \| Research and Development
Income Taxes Disclosure [Line Items]
Tax credit carryforwards				$ 3,556
Federal
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards expire through 2037				$ 22,399
Operating loss carryforwards expiration year				2037
Net operating loss carryforwards without expiration				$ 151,708
Tax credit carryforwards expiration year				2042
Federal \| Internal Revenue Service
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards							$ 46,123		$ 12,400
Federal \| Research and Development
Income Taxes Disclosure [Line Items]
Tax credit carryforwards				$ 8,177
Federal \| Massachusetts
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards				$ 174,107
State
Income Taxes Disclosure [Line Items]
Operating loss carryforwards expiration year				2042
State \| Massachusetts
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards				$ 141,318
Tax credit carryforwards expiration year				2037

Stock-based Compensation (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Summary of Stock Option Activity with in 2014 Stock Incentive Plan and 2019 Incentive Award Plan

The below summary includes stock option activity within the Company’s 2014 Stock Incentive Plan and 2019 Incentive Award Plan for the three months ended March 31, 2023:


	Number of shares in Plans			Weighted average exercise price		Weighted average remaining contractual term (in years)		Aggregate intrinsic value
Outstanding as of December 31, 2022		5,742,053		$	2.35		6.69	$	9,114

Granted		27,350			4.66		8.61		—
Exercised		(2,969	)		0.07		—	$	1
Forfeited		(166,346	)		2.20		—		—

Outstanding as of March 31, 2023		5,600,088		$	2.36		5.63	$	4

Options exercisable as of March 31, 2023		4,789,470		$	2.40		5.29	$	4

Options unvested as of March 31, 2023		810,618		$	2.13		7.65	$	—

A summary of the stock option activity under the 2014 Plan and the 2019 Plan are as follows:


	Number of shares			Weighted average exercise price (1)		Weighted average remaining contractual term (in years)		Aggregate intrinsic value
Outstanding as of December 31, 2020		6,816,798		$	10.11		8.45	$	171,415
Granted		1,357,426			32.76		8.07		—
Exercised		(642,314	)		2.02		—	$	11,652
Forfeited		(701,873	)		16.48		—		—

Outstanding as of December 31, 2021		6,830,037		$	5.35		7.76	$	6,987

Granted		221,176			1.78		8.32		—
Exercised		(10,047	)		1.24		—	$	37
Forfeited		(1,299,113	)		18.04		—		—

Outstanding as of December 31, 2022		5,742,053		$	2.35		6.69	$	9,114

Options exercisable as of December 31, 2022		4,579,486		$	2.40		6.39	$	7,071

Options unvested as of December 31, 2022		1,162,567		$	2.12		7.84	$	2,043

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s common stock.

(1)

On August 17, 2022, the Company’s Board of Directors approved the repricing of all options granted under the 2019 Incentive Award Plan that were held by then current employees, executives, directors, and consultants for which the exercise price per share was greater than the closing price per share of the Company’s common stock on August 17, 2022 (Underwater Options) by reducing the exercise price of each Underwater Option to $2.14, the closing price per share of the Company’s common stock on August 17, 2022.

See “

Repricing of stock options

” section for more information.

Summary of Grant-date Fair Value of Stock Options Granted on Weighted Average Basis

The assumptions that the Company used to determine the grant-date fair value of stock options granted to employees and directors were as follows, presented on a weighted average basis:


	March 31, 2023
Risk-free interest rate		3.6	%
Expected term (in years)		6.0
Expected volatility		92.0	%
Expected dividend yield		0.0	%

The assumptions that the Company used to determine the grant-date fair value of stock options granted to employees and directors were as follows, presented on a weighted average basis:


	Year Ended December 31,
	2022			2021
Risk-free interest rate		3.0	%		0.5	%
Expected term (in years)		6.0			6.0
Expected volatility		80.0	%		79.8	%
Expected dividend yield		0.0	%		0.0	%

Summary of Recognized Stock-based Compensation

The Company recognized stock-based compensation within the accompanying consolidated statements of operations as follows:


	Three Months Ended March 31,
	2023		2022
Research and development	$	839	$	2,301
General and administrative		2,592		2,965

Total	$	3,431	$	5,266

Restricted Stock Units

Share Based Compensation Arrangement By Share Based Payment Award [Line Items]

Summary of Status of Restricted Common Stock and Restricted Stock Units

The below summary includes restricted stock unit activity within the Company’s 2019 Incentive Award Plan for the three months ended March 31, 2023:


	Number of shares			Weighted average fair value
Unvested, December 31, 2022		3,101,650		$	2.78
Awarded		1,666,340			4.78
Vested		(306,775	)		1.17
Forfeited		(819,050	)		3.85

Unvested as of March 31, 2023		3,642,165		$	3.59

The below summary includes restricted stock unit activity within the Company’s 2019 Incentive Award Plan for the year ended December 31, 2022.


	Number of shares			Weighted average fair value
Unvested, December 31, 2021		626,300		$	9.54
Awarded		3,576,650			3.01
Vested		(551,450	)		9.54
Forfeited		(549,850	)		5.06

Unvested, December 31, 2022		3,101,650		$	2.80

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 35
-Paragraph 1D
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480483/718-10-35-1D

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 26: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Fair Value Measurements

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Fair Value Measurements

3. Fair value measurements

The Company’s financial assets are measured at fair value on a recurring basis by level within the fair value hierarchy at March 31, 2023 and December 31, 2022 are summarized as follows:


	March 31, 2023
	Fair Value Hierarchy		Fair Market Value
Cash equivalents:
Money market funds		Level 1		37,844
Investments:
Short-term marketable securities		Level 2		25,797

			$	63,641


	December 31, 2022
	Fair Value Hierarchy		Fair Market Value
Cash equivalents:
Money market funds		Level 1		30,649
Investments:
Short-term marketable securities		Level 2		31,143

			$	61,792

Silicon Valley Bank (SVB) was closed on March 10, 2023 by the California Department of Financial Protection and Innovation, which appointed the Federal Deposit Insurance Corporation (FDIC) as receiver. The FDIC then reopened SVB as Silicon Valley Bridge Bank, N.A. (SVBB). At March 31, 2023, SVBB continues to hold the Company’s term loan, deposit and sweep accounts, and security deposit for the Company’s office space under the existing terms and covenants which were in place at SVB prior to the receivership. The Company is actively working to move these accounts to another financial institution.

3. Fair value measurements

The Company’s financial assets measures at fair value on a recurring basis by level within the fair value hierarchy at December 31, 2022 and 2021 are summarized as follows:


			December 31, 2022
	Fair Value Hierarchy		Amortization Cost		Unrealized Gain (Loss)			Fair Market Value
Money market funds		Level 1	$	30,648	$	1		$	30,649
Short-term marketable securities		Level 2		31,280		(137	)		31,143

			$	61,928	$	(136	)	$	61,792


			December 31, 2021
	Fair Value		Amortization		Unrealized			Fair Market
	Hierarchy		Cost		Loss			Value
Money market funds		Level 1	$	48,160	$	—		$	48,160
Short-term marketable securities		Level 2		51,116		(44	)		51,072
Long-term marketable securities		Level 2		11,764		(45	)		11,719

			$	111,040	$	(89	)	$	110,951

At December 31, 2022 and 2021, we held 14 and 18 debt securities, respectively, that were in an unrealized loss position. The unrealized losses at December 31, 2022 and 2021 were attributable to changes in interest rates and do not represent credit losses. The Company does not intend to sell the investments before recovery of their amortized cost bases, which may be at maturity. All investments mature within twelve months from December 31, 2022. The following tables summarize the Company’s debt securities in an unrealized loss position, aggregated by length of time in a continuous unrealized loss position.


	December 31, 2022
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)


	December 31, 2021
	Less than 12 Months					More than 12 Months				Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss		Fair Market Value		Unrealized Loss
Short-term marketable securities	$	32,991	$	(29	)	$	—	$	—	$	32,991	$	(29	)
Long-term marketable securities		11,719		(45	)		—		—		11,719		(45	)

	$	44,710	$	(74	)	$	—	$	—	$	44,710	$	(74	)

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Stock-based Compensation

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Share-Based Payment Arrangement [Abstract]

Stock-based Compensation

10. Stock-based compensation

Stock options

The below summary includes stock option activity within the Company’s 2014 Stock Incentive Plan and 2019 Incentive Award Plan for the three months ended March 31, 2023:


	Number of shares in Plans			Weighted average exercise price		Weighted average remaining contractual term (in years)		Aggregate intrinsic value
Outstanding as of December 31, 2022		5,742,053		$	2.35		6.69	$	9,114

Granted		27,350			4.66		8.61		—
Exercised		(2,969	)		0.07		—	$	1
Forfeited		(166,346	)		2.20		—		—

Outstanding as of March 31, 2023		5,600,088		$	2.36		5.63	$	4

Options exercisable as of March 31, 2023		4,789,470		$	2.40		5.29	$	4

Options unvested as of March 31, 2023		810,618		$	2.13		7.65	$	—

Stock option valuation

The assumptions that the Company used to determine the grant-date fair value of stock options granted to employees and directors were as follows, presented on a weighted average basis:


	March 31, 2023
Risk-free interest rate		3.6	%
Expected term (in years)		6.0
Expected volatility		92.0	%
Expected dividend yield		0.0	%

The weighted-average grant date fair value of options granted during the three months ended March 31, 2023 and 2022 was $3.58 and $3.55, respectively.

The total grant date fair value of options vested during the three months ended March 31, 2023 and 2022 was $2,874 and $5,097, respectively.

Repricing of stock options

On August 17, 2022, the Board of Directors approved the repricing of all options granted under the 2019 Incentive Award Plan that were held by then current employees, executives, directors, and consultants for which the exercise price per share was greater than the closing price per share of the Company’s common stock on August 17, 2022 (Underwater Options) by reducing the exercise price of each Underwater Option to $2.14, the closing price per share of the Company’s common stock on August 17, 2022. Except for the modification of the exercise price, all other terms and conditions of the Underwater Options remain in effect.

The option repricing resulted in incremental stock-based compensation of $2,505, of which $170 was recorded as expense in the three months ended March 31, 2023. At March 31, 2023, $705 incremental expense remains which will be recognized as expense over the requisite service period in which the options vest.

Restricted stock units

The below summary includes restricted stock unit activity within the Company’s 2019 Incentive Award Plan for the three months ended March 31, 2023:


	Number of shares			Weighted average fair value
Unvested, December 31, 2022		3,101,650		$	2.78
Awarded		1,666,340			4.78
Vested		(306,775	)		1.17
Forfeited		(819,050	)		3.85

Unvested as of March 31, 2023		3,642,165		$	3.59

Stock-based compensation

The Company recognized stock-based compensation within the accompanying consolidated statements of operations as follows:


	Three Months Ended March 31,
	2023		2022
Research and development	$	839	$	2,301
General and administrative		2,592		2,965

Total	$	3,431	$	5,266

As of March 31, 2023, total unrecognized stock-based compensation expense relating to unvested stock options and restricted stock units was $17,610. This amount is expected to be recognized over a weighted-average period of 1.72 years.

9. Stock-based compensation

On November 13, 2014, the Company adopted the 2014 Stock Incentive Plan (2014 Plan). All of the Company’s employees, officers, directors, and consultants are eligible to be granted options to purchase common shares and restricted stock under the terms of the 2014 Plan. The Company reserved an aggregate of 8,550,415 shares of common stock for issuance under the 2014 Plan. As of December 31, 2022, there were no shares of common stock available for future grants under the 2014 Plan.

On September 17, 2019, the Company’s board of directors and on September 19, 2019, its stockholders approved and adopted the 2019 Incentive Award Plan (2019 Plan). Under the 2019 Plan, the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units, and other stock and cash-based awards to individuals who are then employees, officers, directors or consultants of the Company, and employees and consultants of the Company’s subsidiaries. A total of 3,100,000 shares of common stock were approved to be

initially reserved for issuance under the 2019 plan. The number of shares under the 2014 Plan subject to outstanding awards as of the effective date of the 2019 Plan that are subsequently canceled, forfeited or repurchased by the Company will be added to the shares reserved under the 2019 Plan. In addition, the number of shares of common stock available for issuance under the 2019 Plan will be automatically increased on the first day of each calendar year during the

ten-year

term of the 2019 Plan, beginning with January 1, 2020 and ending with January 1, 2029, by the amount equal to 4% of the outstanding number of shares of the Company’s common stock on December 31 of the preceding calendar year or such lesser amount as determined by the Company’s board of directors.

All stock option grants are

non-statutory

stock options except option grants to employees (including officers and directors) intended to qualify as incentive stock options under the Internal Revenue Code of 1986, as amended. Incentive stock options may not be granted at less than the fair market value of the Company’s common stock on the date of grant, as determined in good faith by the Board of Directors at its sole discretion. Nonqualified stock options may be granted at an exercise price established by the Board of Directors at its sole discretion (which has not been less than fair market value on the date of grant) and the vesting periods may vary. Vesting periods are generally four years and are determined by the Board of Directors. Stock options become exercisable as they vest. Options granted under the 2014 Plan and the 2019 Plan expire no more than ten years from the date of grant.

Stock options

A summary of the stock option activity under the 2014 Plan and the 2019 Plan are as follows:


	Number of shares			Weighted average exercise price (1)		Weighted average remaining contractual term (in years)		Aggregate intrinsic value
Outstanding as of December 31, 2020		6,816,798		$	10.11		8.45	$	171,415
Granted		1,357,426			32.76		8.07		—
Exercised		(642,314	)		2.02		—	$	11,652
Forfeited		(701,873	)		16.48		—		—

Outstanding as of December 31, 2021		6,830,037		$	5.35		7.76	$	6,987

Granted		221,176			1.78		8.32		—
Exercised		(10,047	)		1.24		—	$	37
Forfeited		(1,299,113	)		18.04		—		—

Outstanding as of December 31, 2022		5,742,053		$	2.35		6.69	$	9,114

Options exercisable as of December 31, 2022		4,579,486		$	2.40		6.39	$	7,071

Options unvested as of December 31, 2022		1,162,567		$	2.12		7.84	$	2,043

(1)

See “

Repricing of stock options

” section for more information.

Stock option valuation

The assumptions that the Company used to determine the grant-date fair value of stock options granted to employees and directors were as follows, presented on a weighted average basis:


	Year Ended December 31,
	2022			2021
Risk-free interest rate		3.0	%		0.5	%
Expected term (in years)		6.0			6.0
Expected volatility		80.0	%		79.8	%
Expected dividend yield		0.0	%		0.0	%

The weighted-average grant date fair value of options granted to employees during the years ended December 31, 2022 and 2021 was $1.58 and $22.39 respectively.

The total grant date fair value of options vested during the years ended December 31, 2022 and 2021 was $14,219 and $16,304, respectively.

Repricing of stock options

On August 17, 2022, the Board of Directors approved the repricing of each Underwater Option to $2.14, the closing price per share of the Company’s common stock on August 17, 2022. Except for the modification of the exercise price, all other terms and conditions of the Underwater Options remain in effect.

The option repricing resulted in incremental stock-based compensation of $2,505, of which $1,630 was recorded as expense in the year ended December 31, 2022 and $875 will be recognized as expense over the remaining vesting period.

Restricted stock units

The below summary includes restricted stock unit activity within the Company’s 2019 Incentive Award Plan for the year ended December 31, 2022.


	Number of shares			Weighted average fair value
Unvested, December 31, 2021		626,300		$	9.54
Awarded		3,576,650			3.01
Vested		(551,450	)		9.54
Forfeited		(549,850	)		5.06

Unvested, December 31, 2022		3,101,650		$	2.80

Stock-based compensation

Stock-based compensation expense of $19,831 and $21,750 for the years ended December 31, 2022 and 2021 respectively, is included in research and development and general and administrative expenses in the Company’s consolidated statements of operations and comprehensive loss.

As of December 31, 2022 and 2021, total unrecognized stock-based compensation expense relating to unvested stock options and restricted stock units was $19,537 and $39,112, respectively. This amount is expected to be recognized over a weighted-average period of 1.55 years and 2.49 years, respectively.

Restructuring

3 Months Ended

Mar. 31, 2023

Restructuring and Related Activities [Abstract]

Restructuring

17. Restructuring

On February 13, 2023, the Company announced the topline results for the Phase 2b study of

FX-322

(FX-322-208)

which failed to achieve its primary efficacy endpoint of an improvement in speech perception. As a result, the Company also announced that it would be discontinuing the

FX-322

and

FX-345

hearing development programs and focusing resources on its remyelination in MS development program. This restructuring resulted in a 55% reduction in the Company’s workforce.

The Company expects to incur a total of approximately $4,329 in restructuring-related expenses, of which $3,970 was expensed in the three months ended March 31, 2023. The total estimated restructuring charges consist of accelerated depreciation expense of $360, accelerated hearing program expense of $129, and severance and other benefit-related costs of $3,840, of which $3,481 was expensed in the three months ended March 31, 2023 and the remaining $359 will be expensed in the second quarter of 2023.

During the three months ended March 31, 2023, the following restructuring-related charges were included in the Consolidated Statement of Operations:


	Severance and other benefit-related costs		Accelerated depreciation charges		Accelerated hearing program charges		Total

Research and development	$	1,932	$	360	$	129	$	2,421
General and administrative		1,549		—		—		1,549

Total	$	3,481	$	360	$	129	$	3,970

At March 31, 2023, the liability for the restructuring is classified as current and included in accrued expenses in the Consolidated Balance Sheets.


	Accelerated hearing program charges		Severance and other benefit-related costs		Total

Liability balance as of December 31, 2022	$	—	$	—	$	—
Net charges		129		3,329		3,458

Liability balance as of March 31, 2023	$	129	$	3,329	$	3,458

Income Taxes

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Income Tax Disclosure [Abstract]

Income Taxes

12. Income taxes

The Company’s total provision is based on the United States statutory rate of 21%, increased by state taxes and reduced by a full valuation allowance on the Company’s deferred tax assets. The income tax expense for the three months ended March 31, 2023 and 2022 represents state taxes on interest income earned by the Company’s subsidiary, Frequency Therapeutics Securities Corporation, a Massachusetts Securities Corporation.

ASC 740 requires a valuation allowance to reduce the deferred tax assets reported if, based on the weight of the evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. After consideration of all the evidence, both positive and negative, the Company has recorded a valuation allowance against its deferred tax assets at March 31, 2023 and December 31, 2022 because the Company’s management has determined that it is more likely than not that the Company will not recognize the benefits of its federal and state deferred tax assets primarily due to its cumulative loss position.

Since inception in 2014, the Company has generated cumulative federal and state net operating loss and research and development credit carryforwards for which no net tax benefit has been recorded due to uncertainty around utilizing these tax attributes within the respective carryforward periods.

11. Income taxes

Since inception in 2014, the Company has generated cumulative federal and state net operating loss and research and development credit carryforwards for which the Company has not recorded any net tax benefit due to uncertainty around utilizing these tax attributes within the respective carryforward periods.

As of December 31, 2022, the Company had federal net operating loss carryforwards of approximately $174,107 and Massachusetts state operating loss carryforwards of approximately $141,318 which may be available to offset future taxable income. The U.S. federal net operating loss carryforwards include $22,399 available to reduce future taxable income through 2037 and approximately $151,708 which do not expire and are available to reduce future taxable income indefinitely. The state net operating loss carryforwards are available to offset future taxable income through 2042. As of December 31, 2022, the Company also had federal and Massachusetts research and development tax credit carryforwards of $8,177 and $3,556, respectively, which are available to offset federal and state tax liabilities through 2042 and 2037, respectively.

Realization of future tax benefits is dependent on many factors, including the Company’s ability to generate taxable income within the net operating loss carryforward period. Net operating loss and tax credit carryforwards may become subject to an annual limitation in the event of certain cumulative changes in the ownership interest of significant shareholders over a three-year period in excess of 50%, as provided under Sections 382 and 383 of the Code, respectively, as well as similar state provisions. These ownership changes may limit the number of carryforwards that can be utilized annually to offset future taxable income. In general, an ownership change, as defined by Section 382 of the Code, results from transactions increasing the ownership of certain shareholders or public groups in the stock of a corporation by more than 50% over a rolling three-year period. The Company has completed several financings and has conducted a study to assess whether a change of control has occurred or whether there have been multiple changes of control since inception and has determined that an ownership change did occur in March 2017. Accordingly, utilization of $12,400 of the U.S. net operating loss carryforwards which were incurred prior to March 2017

(pre-ownership

change) is limited under Section 382 of the Code. After the limitations under Section 382 of the Code, the Company may utilize approximately $10,800 of its

pre-ownership

change net operating loss carryforwards based upon an annual usage of approximately $1,600 for each of the next five years after the ownership change and approximately $180 for each of the 15 years thereafter. The remaining

pre-March

2017 ownership change net operating losses of approximately $1,600 were written off due to expiration under limitation. The limitation has been determined by first multiplying the value of our stock at the time of the ownership change by the applicable long-term

tax-exempt

rate. These

carryforwards may be subject to further annual limitations under Section 382 of the Code in the event of future changes in ownership. Additionally, the Company has determined an ownership changed occurred in October of 2019 as a result of the IPO. Accordingly, utilization of approximately $46,123 of the U.S. net operating loss carryforwards incurred prior to October 2019 is also limited under Section 382 of the Code. The Company has determined it will be able to utilize the entire $46,123 of its

pre-ownership

change net operating loss carryforwards based upon the limitations calculated from the October 2019 ownership change. These carryforwards may be subject to further annual limitations under Section 382 of the Code in the event of future changes in ownership.

ASC 740 requires a valuation allowance to reduce the deferred tax assets reported if, based on the weight of the evidence, it is more likely than not that some portion or all of the deferred tax assets will not be realized. After consideration of all the evidence, both positive and negative, the Company has recorded a valuation allowance against its deferred tax assets at December 31, 2022 and 2021 because the Company’s management has determined that it is more likely than not that the Company will not recognize the benefits of its federal and state deferred tax assets primarily due to its cumulative loss position and, as a result, a valuation allowance of approximately $77,288 and $50,931 as of December 31, 2022 and 2021 has been established.

The Company has no unrecognized tax benefits. The Company has not, as yet, conducted a study of its research and development credit carryforwards. Such a study may result in an adjustment to the Company’s research and development credit carryforwards; however, until a study is completed, and any adjustment is known, no amounts are being presented as an uncertain tax position. A full valuation allowance has been provided against the Company’s research and development credits and, if an adjustment were required, this adjustment would be offset by an adjustment to the valuation allowance. Thus, there would be no impact to the consolidated balance sheet or consolidated statements of operations if an adjustment were required. The Company has elected to recognize interest and penalties related to income tax matters as a component of income tax expense, of which no interest or penalties were recorded for the years ended December 31, 2022 and 2021.

The Company files income tax returns in the U.S. and Massachusetts. The statute of limitations for assessment by the Internal Revenue Service and Massachusetts tax authorities remains open for all years since 2014. To the extent the Company has tax attribute carryforwards, the tax years in which the attribute was generated may still be adjusted upon examination by the Internal Revenue Service or state authorities to the extent utilized in a future period. No federal or state tax audits are currently in process.

A reconciliation of the Company’s

pre-tax

loss for the years ended December 31, 2022 and 2021 is as follows:


	2022			2021
Domestic	$	(81,586	)	$	(84,624	)
Foreign		4			(47	)

Total	$	(81,582	)	$	(84,671	)

The Company’s provision at December 31, 2022 and 2021 consist of the following:


	2022			2021
Current:
Federal	$	—		$	—
State		(2	)		15
Foreign		—			—

Total current	$	(2	)	$	15
Deferred:
Federal		—			—
State		—			—
Foreign		—			—

Total deferred	$	—		$	—

Total (benefit) provision	$	(2	)	$	15

A reconciliation of the U.S. federal statutory income tax rate to the Company’s effective income tax rate for the years ended December 31, 2022 and 2021 is as follows:


	2022			2021
U.S federal statutory income tax rate		21.0	%		21.0	%
Permanent differences		(0.1	)		—
State income taxes, net of federal benefit		5.4			2.7
Research and development tax credits		5.1			3.6
State rate changes		3.7			—
Stock compensation deductions		(2.8	)		1.6
Other items		—			(0.7	)
Change in deferred tax asset valuation allowance		(32.3	)		(28.2	)

Effective income tax rate		—	%		—	%

The Company’s deferred tax assets at December 31, 2022 and 2021 consist of the following:


	2022			2021
Deferred tax assets:
Net operating loss carryforwards	$	45,512		$	36,590
Research and development tax credits		11,163			7,026
Capitalized research and development costs		10,042			—
Intangibles		478			392
Stock compensation		9,507			6,554
Accrued expenses		—			107
Deferred revenue		—			—
Other		357			176
Fixed assets		282			265
Lease liability		7,735			7,269

Gross deferred tax asset		85,076			58,379
Valuation allowance		(77,288	)		(50,931	)

Net deferred tax assets	$	7,788		$	7,448
Deferred tax liabilities:
Right of use asset		(7,788	)		(7,448	)

Net deferred tax asset (liability)	$	—		$	—

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Net Loss Per Share (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Earnings Per Share [Abstract]

Schedule of Basic and Diluted Net Loss per Share

Diluted net loss per share is the same as basic net loss per share for the three months ended March 31, 2023 and 2022 since all potential shares of common stock instruments are anti-dilutive as a result of the loss for such periods.


	Three Months Ended March 31,
	2023			2022
Numerator:
Net Loss	$	(19,543	)	$	(23,386	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,324,053			34,810,676

Net loss per share attributable to common stockholders-basic and diluted	$	(0.55	)	$	(0.67	)

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Year Ended December 31,
	2022			2021
Numerator:
Net loss	$	(81,580	)	$	(84,686	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,075,924			34,351,274

Net loss per share-basic and diluted	$	(2.33	)	$	(2.47	)

Computation of Diluted Net Loss per Share

The Company excluded the following potential shares of common stock from the computation of diluted net loss per share because including them would have had an anti-dilutive effect.


	Three Months Ended March 31,
	2023		2022
Unvested restricted stock units		3,642,165		2,165,350
Outstanding stock options		5,600,088		6,610,663

Total		9,242,253		8,776,013

Summary of Significant Accounting Policies (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Accounting Policies [Abstract]

Property And Equipment


	Estimated useful life
Lab equipment		3 years
Software		3 years
Furniture and office equipment		3 years

Schedule of Basic and Diluted Net Loss per Share


	Three Months Ended March 31,
	2023			2022
Numerator:
Net Loss	$	(19,543	)	$	(23,386	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,324,053			34,810,676

Net loss per share attributable to common stockholders-basic and diluted	$	(0.55	)	$	(0.67	)

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Year Ended December 31,
	2022			2021
Numerator:
Net loss	$	(81,580	)	$	(84,686	)

Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		35,075,924			34,351,274

Net loss per share-basic and diluted	$	(2.33	)	$	(2.47	)

Accrued Expenses (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consist of the following:


	March 31, 2023		December 31, 2022
Payroll and employee related expenses	$	3,831	$	4,216
Professional fees		550		377
Third-party research and development expenses		457		773
Other		729		525

Total	$	5,567	$	5,891

Accrued expenses consist of the following:


	December 31, 2022		December 31, 2021
Payroll and employee related expenses	$	4,216	$	4,375
Professional fees		377		767
Third-party research and development expenses		773		840
Other		525		119

Total	$	5,891	$	6,101

Leases (Tables)

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Schedule of Leases


Other information	December 31, 2022
Weighted-average remaining operating lease term		8.4 years
Weighted-average discount rate		8.5	%

Schedule of Reconciles the Undiscounted Cash Flows to the Operating Lease Liability

The table below reconciles the undiscounted cash flows to the operating lease liability recorded on the consolidated balance sheet as of December 31, 2022.


2023		4,273
2024		4,402
2025		4,534
2026		4,670
2027		4,810
Thereafter		17,530

Total minimum lease payments		40,219
Less: amount of lease payments representing interest		(11,437	)

Present value of future lease payments		28,782
Less: current lease liabilities		(2,021	)

Noncurrent lease liabilities	$	26,761

Schedule of Future Aggregate Minimum Payments

Future aggregate minimum payments under the noncancelable operating lease as of December 31, 2022 are as follows:


2023	$	4,273
2024		4,402
2025		4,534
2026		4,670
2027 and beyond		22,340

Total minimum lease payments	$	40,219

Stockholders' Equity

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Equity [Abstract]

Stockholders' Equity

9. Stockholders’ equity

Preferred stock

The Company has authorized 10,000,000 shares of $0.001 par value preferred stock of which no shares were issued or outstanding as of March 31, 2023.

Common Stock

The Company has authorized 200,000,000 shares of $0.001 par value common stock of which there were 35,751,956 and 35,262,083 shares issued and outstanding as of March 31, 2023 and December 31, 2022, respectively. Common shares are voting, and dividends may be paid when, as and if declared by the Board of Directors.

The Company has reserved the following shares of common stock for future issuance as of March 31, 2023 and December 31, 2022:


	March 31, 2023		December 31, 2022
Stock options outstanding		5,600,088		5,742,053
Shares available for future grant under incentive plans		1,690,405		988,216

		7,290,493		6,730,269

Equity Offerings

On December 10, 2021, the Company entered into an Equity Distribution Agreement (the Sales Agreement) with Oppenheimer & Co. Inc. (the Sales Agent) to sell shares of the Company’s common stock, par value $0.001 per share, with aggregate gross sales proceeds of up to $125,000, from time to time, through an “at the market” equity offering program.

Issuance costs incurred related to the Sales Agreement are classified as long-term assets on the balance sheet at March 31, 2023. During the three months ended March 31, 2022, the Company sold 12,767 shares of common stock under the ATM program for net proceeds of approximately $50. No shares were sold during the three months ended March 31, 2023.

8. Stockholders’ equity

Preferred stock

The Company has authorized 10,000,000 shares of $0.001 par value preferred stock of which no shares were issued or outstanding as of December 31, 2022.

Common stock

The Company has authorized 200,000,000 shares of $0.001 par value common stock of which 35,262,083 were issued and outstanding as of December 31, 2022. Common shares are voting, and dividends may be paid when, as and if declared by the Board of Directors.

The Company has reserved the following shares of common stock for future issuance as of December 31, 2022 and 2021:


	December 31, 2022		December 31, 2021
Stock options outstanding		5,742,053		6,830,037
Shares available for future grant under stock option plan		988,216		1,552,630

		6,730,269		8,382,667

Equity Offerings

On December 10, 2021, the Company entered into an Equity Distribution Agreement (Sales Agreement) with Oppenheimer & Co. Inc. (Sales Agent) to sell shares of the Company’s common stock, par value $0.001 per share, with aggregate gross sales proceeds of up to $125,000, from time to time, through an “at the market” equity offering program. Subject to the terms and conditions of the Sales Agreement, the Sales Agent may sell the shares by methods deemed to be an “at the market offering” as defined in Rule 415 promulgated under the Securities Act of 1933, as amended, including sales made through The Nasdaq Global Select Market, on any other existing trading market for the Common Stock, to or through a market maker, or, if expressly authorized by the Company, in privately negotiated transactions. The Company or Sales Agent may terminate the Sales Agreement upon notice to the other party and subject to other conditions. The Company will pay the Sales Agent a commission equal to 3.0% of the gross proceeds of any Common Stock sold through the Sales Agent under the Sales Agreement and has provided the Sales Agent with customary indemnification rights.

Issuance costs incurred related to the Sales Agreement are classified as long-term assets on the balance sheet at December 31, 2022.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-based Compensation - Summary of Recognized Stock-based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 3,431	$ 5,266
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	839	2,301	$ 19,831
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation	$ 2,592	$ 2,965		$ 21,750

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Net Loss Per Share - Schedule of Basic And Diluted Net Loss per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net Loss	$ (19,543)	$ (23,386)	$ (81,580)	$ (84,686)
Denominator:
Weighteds Average Number Of Share Outstanding Basic And Diluted	$ 35,324,053	$ 34,810,676	$ 35,075,924	$ 34,351,274
Net loss per share attributable to common stockholders-basic and diluted	$ (0.55)	$ (0.67)	$ (2.33)	$ (2.47)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Restructuring (Additional Information) (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended
	Feb. 13, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2023	Dec. 31, 2022
Restructuring Charges [Abstract]
Reduction in Workforce due to Restructuring	55.00%
restructuring-related expenses			$ 3,970	$ 4,329
Restructuring and Related Cost, Accelerated Depreciation			360
Accelerated Hearing Program Charges			129
Severance Costs		$ 359	$ 3,481	$ 3,840	$ 3,840

Fair Value Measurements - Schedule of Financial Assets Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost	$ 25,799	$ 31,280
Unrealized Loss	(2)	(317)
Fair Market Value	25,797	31,143
Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost		61,928	$ 111,040
Unrealized Loss		(136)	(89)
Fair Market Value	63,641	61,792	110,951
Money Market Funds \| Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost		30,648
Unrealized Gain		1
Fair Market Value		30,649
Money Market Funds \| Level 1 \| Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost			48,160
Unrealized Gain			0
Fair Market Value	37,844	30,649	48,160
Short-term Marketable Securities \| Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost		31,280
Unrealized Loss		(137)
Fair Market Value		31,143
Short-term Marketable Securities \| Level 2 \| Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost			51,116
Unrealized Loss			(44)
Fair Market Value	$ 25,797	$ 31,143	51,072
Long-term Marketable Securities \| Level 2 \| Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost			11,764
Unrealized Loss			(45)
Fair Market Value			$ 11,719

Leases - Additional Information (Details) $ in Thousands			12 Months Ended
Leases - Additional Information (Details) $ in Thousands	Dec. 11, 2020	Jan. 07, 2020 ft² Term	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Lessee Lease Description [Line Items]
Lease expense \| $			$ 4,802	$ 4,960
Hayden LLC \| Lexington Lease
Lessee Lease Description [Line Items]
Lease expiration date		May 31, 2031
Rentable square feetspace \| ft²		61,307
Lease commencement date		Dec. 11, 2020
Number of additional lease extension terms \| Term		2
Lease extension term		5 years
Lease Termination Agreement \| ARE-MA Region No. 20, LLC
Lessee Lease Description [Line Items]
Lease expiration date	Mar. 31, 2021

Sublease (Tables)

12 Months Ended

Dec. 31, 2022

Leases [Abstract]

Summary Of Expected Future Sublease Income


Years Ending December 31,	Sublease Income
2023	$	2,371
2024		1,383

Total future sublease income	$	3,754

Stockholders' Equity - Additional Information (Details) - USD ($)		3 Months Ended		12 Months Ended
	Dec. 10, 2021	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Class Of Stock [Line Items]
Preferred stock, shares authorized		10,000,000		10,000,000	10,000,000
Preferred Stock, value per share		$ 0.001		$ 0.001	$ 0.001
Preferred stock, issued shares		0		0	0
Preferred stock, outstanding shares		0		0	0
Common stock, authorized shares		200,000,000		200,000,000	200,000,000
Common stock, par value		$ 0.001		$ 0.001	$ 0.001
Common stock, sale of price per share	$ 0.001
Common stock, issued shares		35,751,956		35,262,083	34,611,213
Proceeds from Issuance of Common Stock		$ 1,000	$ 61,000	$ 60,000	$ 1,298,000
Common stock, outstanding shares		35,751,956		35,262,083	34,611,213
Common Stock
Class Of Stock [Line Items]
Common stock, outstanding shares		35,751,956	34,976,409	35,262,083	34,611,213	33,964,000
Equity Distribution Agreement \| Common Stock
Class Of Stock [Line Items]
Common stock, sale of price per share	$ 0.001
Sales Agent Commission	3.00%
Equity Distribution Agreement \| Common Stock \| Maximum
Class Of Stock [Line Items]
Proceeds from Issuance of Common Stock	$ 125,000
ATM Program \| Common Stock
Class Of Stock [Line Items]
Proceeds from Issuance of Common Stock			$ 50,000
Common stock shares issued and sold		0	12,767

Fair Value Measurements (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Fair Value Disclosures [Abstract]

Schedule of Financial Assets Measured at Fair Value on Recurring Basis

The Company’s financial assets measures at fair value on a recurring basis by level within the fair value hierarchy at December 31, 2022 and 2021 are summarized as follows:


			December 31, 2022
	Fair Value Hierarchy		Amortization Cost		Unrealized Gain (Loss)			Fair Market Value
Money market funds		Level 1	$	30,648	$	1		$	30,649
Short-term marketable securities		Level 2		31,280		(137	)		31,143

			$	61,928	$	(136	)	$	61,792


			December 31, 2021
	Fair Value		Amortization		Unrealized			Fair Market
	Hierarchy		Cost		Loss			Value
Money market funds		Level 1	$	48,160	$	—		$	48,160
Short-term marketable securities		Level 2		51,116		(44	)		51,072
Long-term marketable securities		Level 2		11,764		(45	)		11,719

			$	111,040	$	(89	)	$	110,951

Schedule of debt securities in an unrealized loss position

The following tables summarize the Company’s debt securities in an unrealized loss position, aggregated by length of time in a continuous unrealized loss position.


	March 31, 2023
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities in unrealized loss position	$	8,407	$	(21	)	$	9,943	$	(54	)	$	18,350	$	(75	)

	$	8,407	$	(21	)	$	9,943	$	(54	)	$	18,350	$	(75	)


	December 31, 2022
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities in unrealized loss position	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

The following tables summarize the Company’s debt securities in an unrealized loss position, aggregated by length of time in a continuous unrealized loss position.


	December 31, 2022
	Less than 12 Months					More than 12 Months					Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss
Short-term marketable securities	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)

	$	17,303	$	(78	)	$	9,927	$	(135	)	$	27,230	$	(213	)


	December 31, 2021
	Less than 12 Months					More than 12 Months				Total
	Fair Market Value		Unrealized Loss			Fair Market Value		Unrealized Loss		Fair Market Value		Unrealized Loss
Short-term marketable securities	$	32,991	$	(29	)	$	—	$	—	$	32,991	$	(29	)
Long-term marketable securities		11,719		(45	)		—		—		11,719		(45	)

	$	44,710	$	(74	)	$	—	$	—	$	44,710	$	(74	)

Stock-based Compensation - Summary of Status of Restricted Common Stock and Restricted Stock Units (Details) - Restricted Stock Units - $ / shares	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Unvested	3,101,650	626,300
Number of shares, Awarded	1,666,340	3,576,650
Number of shares, Vested	(306,775)	(551,450)
Number of shares, Forfeited	(819,050)	(549,850)
Number of shares, Unvested	3,642,165	3,101,650
Weighted average fair value, Unvested	$ 2.78	$ 9.54
Weighted average fair value, Awarded	4.78	3.01
Weighted average fair value, Vested	1.17	9.54
Weighted average fair value, Forfeited	3.85	5.06
Weighted average fair value, Unvested	$ 3.59	2.78
Weighted average fair value, Unvested		$ 2.8

Leases - Schedule of Reconciles the Undiscounted Cash Flows to the Operating Lease (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
2023		$ 4,273
2024		4,402
2025		4,534
2026		4,670
2027		4,810
Thereafter		17,530
Total minimum lease payments		40,219
Less: amount of lease payments representing interest		(11,437)
Present value of future lease payments		28,782
Less: current lease liabilities	$ (2,088)	(2,021)	$ (1,747)
Noncurrent lease liabilities	$ 26,215	$ 26,761	$ 28,851

Research and License Agreements	3 Months Ended	12 Months Ended
Research and License Agreements	Mar. 31, 2023	Dec. 31, 2022
Research and Development [Abstract]
Research and License Agreements	14. License agreements Massachusetts Institute of Technology In December 2016, the Company entered into an exclusive patent license agreement (MIT License Agreement) with the Massachusetts Institute of Technology (MIT), under which the Company received an exclusive, worldwide, royalty-bearing license to certain patent rights to develop, make, have made, use, sell, offer to sell, lease and import products (Licensed Products) and to develop and perform processes (Licensed Processes) which incorporate the licensed technology for the treatment of disease, including but not limited to the prevention and remediation of hearing loss. The Company also has the right to grant sublicenses of its rights under the MIT License Agreement. Upon entering into the MIT License Agreement, the Company paid a $50 license fee payment and issued to MIT shares of our common stock equal to 5% of total then-outstanding capital stock. The Company is required to pay certain annual license maintenance fees which may be credited to running royalties during the same calendar year, if any, and to make potential milestone payments up to $2,900 on each Licensed Product or Licensed Process. The MIT License Agreement will remain in effect until the expiration or abandonment of all issued patents and filed patent applications licensed thereunder remain in effect, unless terminated earlier. The Company has the right to terminate for any reason upon a 3-month prior written notice. In May 2019, the Company entered into an amendment with MIT, updating the diligence milestones for a second Licensed Product. In March 2022, the Company entered into a second amendment with MIT, removing a patent and certain patent applications from the MIT License Agreement which were unrelated to the Company’s hearing and multiple sclerosis (MS) programs and which were not being utilized by the Company. On April 6, 2023, the Company sent MIT a notice stating that the Company would be terminating the MIT License Agreement in 3-months’ time. The Company is not subject to any payments or costs as a result of this termination. The Scripps Research Institute (California Institute for Biomedical Research) In September 2018, the Company entered into a license agreement, (CALIBR License Agreement), with the California Institute for Biomedical Research, (CALIBR), under which the Company received an exclusive, worldwide, royalty-bearing license to certain patent rights to make, have made, use, sell, offer to sell, and import products (CALIBR Licensed Products) which incorporate the licensed technology for the treatment of MS. The Company also has the right to grant sublicenses of its rights under the CALIBR License Agreement. CALIBR reserves the right to use for itself and the right to grant non-exclusive licenses to other nonprofit or academic institutions, for any internal research and educational purposes. Upon entering into the CALIBR License Agreement, the Company made a $1,000 license fee payment. The CALIBR License Agreement shall continue in effect until expiration of all Company obligations to pay royalties. The Company may terminate the CALIBR License Agreement at will upon a 30-day prior written notice. On March 29, 2023, the Company sent CALIBR a notice stating that the Company would be terminating the CALIBR License Agreement in 30 days’ time. The termination became final on or around April 28, 2023. The Company is not subject to any payments or costs as a result of this termination. Massachusetts Eye and Ear (Formerly Massachusetts Eye and Ear Infirmary) In February 2019, the Company entered into an Non-Exclusive Patent License Agreement (MEE License Agreement) with the Massachusetts Eye and Ear (MEE) under which it received a non-exclusive, non-sublicensable, worldwide, royalty-bearing license to certain patent rights to develop, make, have made, use, sell, offer to sell, lease and import products and to develop and perform processes which incorporate the licensed technology for the treatment or prevention of hearing loss (MEE licensed products). Upon entering the MEE License, the Company made a $20 license fee payment. The Company was obligated to pay certain annual license maintenance fees between $5 and $7.5 per each MEE patent family case number included in the licensed MEE patent rights prior to first commercial sale of an MEE licensed product. On February 21, 2023, the Company sent MEE a notice stating that the Company would be terminating the MEE License Agreement in 30 business days’ time. The termination became final on or around April 4, 2023. The Company is not subject to any payments or costs as a result of this termination.	12. Research and license agreements Massachusetts Institute of Technology In December 2016, the Company entered into an exclusive patent license agreement (MIT License Agreement), with the Massachusetts Institute of Technology (MIT), under which the Company received an exclusive, worldwide, royalty-bearing license to certain patent rights to develop, make, have made, use, sell, offer to sell, lease and import products (Licensed Products) and to develop and perform processes (Licensed Processes) which incorporate the licensed technology for the treatment of disease, including but not limited to the prevention and remediation of hearing loss. The Company also has the right to grant sublicenses of its rights under the MIT License Agreement. The Company is required to use diligent efforts to develop and commercialize the Licensed Products or Processes, and to make such products or processes reasonably available to the public and to spend certain minimum amounts on research and development of Licensed Products and/or Processes each year until the first commercial sale of a Licensed Product and/or a first commercial performance of a Licensed Process. The Company is also subject to certain development obligations with regards to a first Licensed Product. The Company has satisfied certain obligations related to preclinical studies and the filing of an IND for a first Licensed Product with its development activities related to FX-322. The Company’s future development obligations are: (i) to commence a Phase 3 clinical trial for such Product within five years of the IND filing for such product, (ii) to file a New Drug Application or equivalent with the FDA or comparable European regulatory agency for such Product within nine years of the IND filing for such Product, and (iii) to make a first commercial sale of such Product within 11 years of the IND filing for such Product. The Company also has certain development obligations for a second Licensed Product. In the event that the Company has failed to fulfill the development timeline obligation with respect to a second Licensed Product and fails to cure such breach within ninety (90) days of written notice by MIT, MIT may restrict the licensed field to the prevention and remediation of hearing loss in humans and animals. The Company does not have the right to control prosecution of the in-licensed patent applications, and its rights to enforce the in-licensed patents are subject to certain limitations. Upon entering into the MIT License Agreement, the Company paid a $50 license fee payment and issued to MIT shares of our common stock equal to 5% of total then-outstanding capital stock. The Company is required to pay certain annual license maintenance fees which may be credited to running royalties during the same calendar year, if any, and to make potential milestone payments up to $2,900 on each Licensed Product or Licensed Process. In addition, the Company is required to pay a low single-digit royalty on Licensed Products and Licensed Processes and a low-twenties royalty on sublicense revenues. The MIT License Agreement will remain in effect until the expiration or abandonment of all issued patents and filed patent applications licensed thereunder remain in effect, unless terminated earlier. The Company has the right to terminate for any reason upon a 3-month prior written notice. MIT shall have the right to terminate if the Company ceases to carry on any business related to the MIT License Agreement. MIT may terminate the MIT License Agreement for the Company’s material breach uncured within ninety (90) days (or thirty (30) days in the case of nonpayment). MIT may also terminate the MIT License Agreement if the Company or our affiliates commence any action against MIT to declare or render any claim of the licensed patent rights invalid, unpatentable, unenforceable, or non-infringed (a patent challenge), or if our sublicensee commences such actions and the Company does not terminate such sublicense within thirty (30) days after MIT’s demand. MIT has the right to increase all payments due, instead of terminating the MIT License Agreement in the case of a patent challenge. In May 2019, the Company entered into an amendment with MIT, updating the diligence milestones for a second Licensed Product. In March 2022, the Company entered into an amendment with MIT, removing a patent and certain patent applications from the MIT License Agreement which were unrelated to the Company’s hearing and MS programs and which were not being utilized by the Company. The patents in-licensed by the Company from MIT pursuant to the MIT License claim inventions created by, among others, Dr. Langer, one of the Company’s directors. Pursuant to MIT’s policy on the ownership, distribution and commercial development of MIT technology, or the MIT Policy, inventors of intellectual property invented at MIT, including the inventors of patents licensed to the Company under the MIT License, are entitled to a portion of the net royalty income derived by MIT from such inventions, but not amounts received by MIT from the sale of common stock previously issued by the Company to MIT pursuant to the MIT License. Accordingly, pursuant to the MIT Policy, Dr. Langer is entitled to receive a portion of the amounts the Company pays to MIT under the MIT License, including the Astellas Royalty Payment and future milestone payments or royalties, if any, that the Company may receive pursuant to the Astellas Agreement. Accordingly, Dr. Langer has received $11 and $6 from MIT under the MIT Policy during the years ended December 31, 2022 and 2021, respectively. Refer to Note 18, “ Related party transactions ”, for all related party disclosures. The Scripps Research Institute (California Institute for Biomedical Research) In September 2018, the Company entered into a license agreement (CALIBR License Agreement) with the California Institute for Biomedical Research (CALIBR) under which the Company received an exclusive, worldwide, royalty-bearing license to certain patent rights to make, have made, use, sell, offer to sell, and import products (CALIBR Licensed Products) which incorporate the licensed technology for the treatment of multiple sclerosis. The Company also have the right to grant sublicenses of our rights under the CALIBR License Agreement. CALIBR reserves the right to use for itself and the right to grant non-exclusive licenses to other nonprofit or academic institutions, for any internal research and educational purposes. The Company is required to use commercially reasonable efforts to develop, manufacture, and sell at least one CALIBR Licensed Product. The Company is also subject to certain milestone timeline obligations, which may be extended in certain circumstances as set forth in the CALIBR License Agreement. In October 2021, the Company entered into an amendment with CALIBR which updated the milestone obligations to: (i) initiate a Phase 2 clinical trial (or equivalent) for a CALIBR Licensed Product by December 31, 2023 and (ii) initiate a Phase 3 clinical trial (or equivalent) for a CALIBR Licensed Product by December 31, 2025. The Company does not have the right to control prosecution of the in-licensed patent applications, and the Company’s rights to enforce the in-licensed patents are subject to certain limitations. Upon entering into the CALIBR License Agreement, the Company made a $1,000 license fee payment and is required to make milestone payments up to $26,000 for each Category of CALIBR Licensed Products (Category 1 is any CALIBR Licensed Products containing a compound that modulates any muscarinic receptor and Category 2 is any CALIBR Licensed Products not included in Category 1 that could differentiate oligodendrocyte precursor cells from in vitro studies and/or are active in animal models relevant to MS). The Company is also required to pay a middle single-digit royalty on CALIBR Licensed Products and a royalty on sublicense revenues ranging from low-teen percentage to 50%. The CALIBR License Agreement shall continue in effect until expiration of all Company obligations to pay royalties. Royalties shall be payable on a country-by-country and CALIBR Licensed Product-by-CALIBR Licensed Product basis upon the later of (1) the expiration or abandonment of all valid claims of the licensed patent rights in such country and (2) ten years from the first commercial sale of each CALIBR Licensed Product. The Company may terminate the CALIBR License Agreement at will upon a 30-day prior written notice. The Company may also elect to terminate its license to one or more licensed patents in any or all jurisdictions by giving ninety (90) days’ prior written notice to CALIBR. CALIBR may terminate the CALIBR License Agreement for material breach uncured within thirty (30) days. CALIBR has the right to terminate or reduce the license to a non-exclusive license if the Company fails to use diligent efforts to develop and commercially exploit CALIBR Licensed Products. Massachusetts Eye and Ear (Formerly Massachusetts Eye and Ear Infirmary) In February 2019, the Company entered into an Non-Exclusive Patent License Agreement (MEE License Agreement) with the Massachusetts Eye and Ear (MEE) under which it received a non-exclusive, non-sublicensable, worldwide, royalty-bearing license to certain patent rights to develop, make, have made, use, sell, offer to sell, lease and import products and to develop and perform processes which incorporate the licensed technology for the treatment or prevention of hearing loss (MEE licensed products). The Company is obligated to use diligent efforts to develop and commercialize the MEE licensed products. The Company met one of its milestone timeline obligations by dosing a first subject in a Phase 2 trial by December 31, 2020. The Company is still subject to a milestone timeline obligation to dose a first subject in a Phase 3 trial by December 31, 2024. The Company does not control the filing, prosecution, enforcement, and defense of any licensed patent rights. Upon entering the MEE License, the Company made a $20 license fee payment. The Company is obligated to pay certain annual license maintenance fees between $5 and $7.5 per each MEE patent family case number included in the licensed MEE patent rights prior to first commercial sale of an MEE licensed product. The Company is also obligated to pay a minimum annual royalty payment of $15 per each MEE patent family case number included in the licensed MEE patent rights after first commercial sale of an MEE licensed product. The Company is also obligated to make milestone payments up to $350 on each product or process that incorporates the licensed patent rights. In addition, the Company has agreed to pay a low single-digit royalty on products and processes that incorporate the licensed patent rights. The MEE License Agreement shall remain in effect until all issued patents and filed patent applications within the licensed patent rights have expired or been abandoned, unless terminated earlier. The Company has the right to terminate the MEE License Agreement at will by giving thirty (30) business days advance written notice to MEE. MEE has the right to terminate the MEE License Agreement if the Company fails to make any payment due within thirty (30) business days after MEE notifies the Company of such failure. MEE shall have the right to terminate if the Company fails to maintain the required insurance. MEE shall also have the right to terminate the MEE License Agreement upon forty-five (45) business days written notice if the Company becomes insolvent. MEE has the right to terminate for any other default not cured within sixty (60) business days written notice. MEE also has the right to terminate if the Company or its affiliates challenge the validity of the licensed patent rights.

Investments (Additional Information) (Details) - Term	Mar. 31, 2023	Dec. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Number of Debt securities unrealized loss position	9	14

Debt - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended		12 Months Ended		25 Months Ended
	Dec. 11, 2020	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Nov. 30, 2022	Apr. 03, 2023
Debt Instrument [Line Items]
Debt instrument, Interest rate		9.25%		9.00%
Interest Expense, Debt		$ 284	$ 178	$ 961	$ 764
Term Loan \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt due							$ 11,667
Loan Agreement
Debt Instrument [Line Items]
Debt instrument final payment	$ 150
Loan Agreement \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument final payment							$ 150
Loan Agreement \| Prime Rate
Debt Instrument [Line Items]
Frequency of interest-only payments	monthly
Monthly interest only payments due	Nov. 30, 2022
Loan maturity date	May 01, 2024
Loan Agreement \| Term Loan
Debt Instrument [Line Items]
Principal balance	$ 15,000
Payment terms, description	The Company made monthly interest only payments through November 30, 2022. The principal balance and interest were to be repaid in equal monthly installments after the interest only period and continue through May 1, 2024 (Loan Maturity Date).
Frequency of interest-only payments						monthly
Monthly interest only payments due	Nov. 30, 2022
Loan maturity date	May 01, 2024
Debt instrument, Interest rate		4.75%		4.75%
Interest rate floor percentage	0.00%
Loan Agreement \| Term Loan \| Prepayment Occurs on or Prior to First Anniversary of Closing Date
Debt Instrument [Line Items]
Debt instrument prepayment premium percentage	2.00%
Loan Agreement \| Term Loan \| Prepayment Occurs After First Anniversary of Closing Date and On or Prior to Second Anniversary of Closing Date
Debt Instrument [Line Items]
Debt instrument prepayment premium percentage	1.00%
Loan Agreement \| Term Loan \| Prepayment Occurs After Second Anniversary of Closing Date
Debt Instrument [Line Items]
Debt instrument prepayment premium percentage	0.00%
Loan Agreement \| Term Loan \| Prime Rate
Debt Instrument [Line Items]
Debt instrument, Interest rate	1.50%

Income Taxes - Schedule of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred Tax Assets, Tax Deferred Expense [Abstract]
Net operating loss carryforwards	$ 45,512	$ 36,590
Research and development tax credits	11,163	7,026
Capitalized research and development costs	10,042	0
Intangibles	478	392
Stock compensation	9,507	6,554
Accrued expenses	0	107
Deferred revenue	0	0
Other	357	176
Fixed assets	282	265
Lease liability	7,735	7,269
Gross deferred tax asset	85,076	58,379
Valuation allowance	(77,288)	(50,931)
Net deferred tax assets	7,788	7,448
Deferred tax liabilities:
Right of use asset	(7,788)	(7,448)
Net deferred tax asset (liability)	$ 0	$ 0

Employee Stock Purchase Plan - Additional Information (Details) - shares			1 Months Ended		6 Months Ended			12 Months Ended
	Sep. 20, 2019	Sep. 20, 2019	Jan. 31, 2023	Jan. 31, 2022	Dec. 31, 2022	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2022	Mar. 31, 2023	Dec. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of eligible employee compensation		15.00%
Shares of common stock reserved for future issuance					6,730,269			6,730,269	7,290,493	8,382,667
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of eligible employee compensation		15.00%
Shares of common stock reserved for future issuance					1,225,527			1,225,527	1,553,394
Period for automatic increase in common available for future issuance		10 years
Percentage of shares issued from outstanding number of shares	1.00%	1.00%
Shares issued			24,754	31,832	24,754	44,774	7,064	31,832

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

+ Details

Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net loss	$ (19,543)	$ (23,386)	$ (81,580)	$ (84,686)
Other comprehensive gain (loss):
Unrealized gain (loss) on marketable securities and money market funds	134	(234)	(136)	(89)
Total other comprehensive gain (loss)	134	(234)	(136)	(89)
Comprehensive loss	$ (19,409)	$ (23,620)	$ (81,716)	$ (84,775)

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

+ Details

Debt	3 Months Ended	12 Months Ended
Debt	Mar. 31, 2023	Dec. 31, 2022
Debt Disclosure [Abstract]
Debt	7. Debt On December 11, 2020, the Company entered into a Loan and Security Agreement (Loan Agreement) with Silicon Valley Bank for a term loan with a principal balance of $15,000. The Company made monthly interest only payments through November 30, 2022. The principal balance and interest were to be repaid in equal monthly installments after the interest only period and continue through May 1, 2024 (Loan Maturity Date). Advances under the Loan Agreement would bear an interest rate equal to the greater of either (i) 1.50% plus the Prime Rate (as reported in The Wall Street Journal, subject to an interest rate floor of zero) or (ii) 4.75%. The interest rate at March 31, 2023 was 9.25%. Interest expense related to the Loan Agreement was $284 for the three months ended March 31, 2023 and $178 for the three months ended March 31, 2022. On April 3, 2023, the Company prepaid the remaining $11,667 due under the Loan Agreement. The final payment of $150, which the Company had been accruing over the term of the loan, was also paid. The Company was not subject to any prepayment premium as the prepayment occurred after the second anniversary of the closing date.	7. Debt On December 11, 2020, the Company entered into a Loan and Security Agreement (Loan Agreement) with a commercial bank for a term loan with a principal balance of $15,000. The Company made monthly interest only payments through November 30, 2022. The principal balance and interest will be repaid in equal monthly installments after the interest only period and continue through May 1, 2024 (Loan Maturity Date). Advances under the Loan Agreement will bear an interest rate equal to the greater of either (i) 1.50% plus the Prime Rate (as reported in The Wall Street Journal , subject to an interest rate floor of zero) or (ii) 4.75%. The interest rate at December 31, 2022 was 9.0%. Interest expense related to the Loan Agreement was $961 for the year ended December 31, 2022 and $764 for the year ended December 31, 2021. The Company may prepay the advance made under the Loan Agreement in whole, at any time subject to a prepayment premium equal to: (a) 2.0% of the then-outstanding principal amount of the advance, if such prepayment occurs on or prior to the first anniversary of the Closing Date; (b) 1.0% of the then-outstanding principal amount of the advance, if such prepayment occurs after the first anniversary of the Closing Date and on or prior to the second anniversary of the Closing Date; and (c) 0.0% of the then-outstanding principal amount of the advance, if such prepayment occurs after the second anniversary of the Closing Date. The prepayment premium is waived if the term loan is refinanced by the bank (in its sole and absolute discretion) on or prior to the Loan Maturity Date. The Company will pay a final payment of $150, which will occur on the earliest of: (i) the Loan Maturity Date; (ii) the date that the Company prepays all of the outstanding principal in full; (iii) the date the loan payments are accelerated due to an event of default; or (iv) the termination of the Loan Agreement. The Company is accruing the final payment over the term of the loan. The term loan is secured by substantially all of the Company’s assets, excluding intellectual property.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481139/470-20-50-1I

+ Details

Fair value measurements - Schedule of debt securities in an unrealized loss (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Market Value, Less than 12 Months	$ 8,407	$ 17,303	$ 44,710
Unrealized Loss, Less than 12 Months	(21)	(78)	(74)
Fair Market Value, More than 12 Months	9,943	9,927	0
Unrealized Loss, More than 12 Months	(54)	(135)	0
Fair Market Value	18,350	27,230	44,710
Unrealized Loss	(75)	(213)	(74)
Short Term Marketable Securities [Member]
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Market Value, Less than 12 Months	8,407	17,303	32,991
Unrealized Loss, Less than 12 Months	(21)	(78)	(29)
Fair Market Value, More than 12 Months	9,943	9,927	0
Unrealized Loss, More than 12 Months	(54)	(135)	0
Fair Market Value	18,350	27,230	32,991
Unrealized Loss	$ (75)	$ (213)	(29)
Long-term Marketable Securities
Debt Securities, Available-for-Sale, Unrealized Loss Position [Line Items]
Fair Market Value, Less than 12 Months			11,719
Unrealized Loss, Less than 12 Months			(45)
Fair Market Value, More than 12 Months			0
Unrealized Loss, More than 12 Months			0
Fair Market Value			11,719
Unrealized Loss			$ (45)

Employee Stock Purchase Plan	3 Months Ended	12 Months Ended
Employee Stock Purchase Plan	Mar. 31, 2023	Dec. 31, 2022
Retirement Benefits [Abstract]
Employee Stock Purchase Plan	11. Employee stock purchase plan On September 20, 2019, the Company’s board of directors and stockholders approved and adopted the 2019 Employee Stock Purchase Plan (the ESPP) which became effective on the date of the Company’s initial public offering of shares of its common stock. The ESPP permits participants to purchase common stock through payroll deductions of up to 15% of their eligible compensation. The number of shares of common stock available for issuance under the ESPP will be automatically increased on the first day of each calendar year during the first ten years of the term of the ESPP, beginning with January 1, 2020 and ending with January 1, 2029, by an amount equal to 1% of the outstanding number of shares of the Company’s common stock on December 31 of the preceding calendar year or such lesser amount as determined by the Company’s board of directors. 31,832 shares were purchased under the ESPP in January 2022 related to the second offering period of 2021, which concluded on December 31, 2021. 24,754 shares were purchased in January 2023 related to the second offering period of 2022, which concluded on December 31, 2022. As of March 31, 2023, a total of 1,553,394 shares remain available for future issuance under the ESPP.	10. Employee stock purchase plan On September 20, 2019, the Company’s board of directors and stockholders approved and adopted the 2019 Employee Stock Purchase Plan (ESPP) which became effective on the date of the Company’s initial public offering of shares of its common stock. The ESPP permits participants to purchase common stock through payroll deductions of up to 15% of their eligible compensation. The number of shares of common stock available for issuance under the ESPP will be automatically increased on the first day of each calendar year during the first ten years of the term of the ESPP, beginning with January 1, 2020 and ending with January 1, 2029, by an amount equal to 1% of the outstanding number of shares of the Company’s common stock on December 31 of the preceding calendar year or such lesser amount as determined by the Company’s board of directors. The Company’s first offering period of 2021 concluded on June 30, 2021 with the purchase of 7,064 shares in July 2021 related to this offering period. The Company’s second offering period of 2021 concluded on December 31, 2021 with the purchase of 31,832 shares in January 2022. The Company’s first offering period of 2022 concluded on June 30, 2022 with the purchase of 44,774 shares in July 2022 related to this offering period. As of December 31, 2022, a total of 1,225,527 shares remain for future offering periods. The Company’s second offering period of 2022 concluded on December 31, 2022 with the purchase of 24,754 shares in January 2023 related to this offering.

Sublease (Additional Information) (Details) $ in Thousands	3 Months Ended	12 Months Ended				13 Months Ended
Sublease (Additional Information) (Details) $ in Thousands	Mar. 31, 2023 USD ($)	Jul. 07, 2024 USD ($)	Jul. 07, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jul. 31, 2024 USD ($)	Jul. 08, 2022 ft²
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Sublease income	$ 593				$ 1,186
SalioGen Therapeutics, Inc. [Member]
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Rentable square feet \| ft²							30,040
Sublease rent per month		$ 203	$ 197	$ 197		$ 203

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Mar. 31, 2023
Summary Of Significant Accounting Policies [Line Items]
Foreign currency exchange (losses) gains	$ (5)	$ 16
Restricted cash	1,699	1,699	$ 1,699
Impairment losses	0	0
Increase in right-of-use asset	$ 0
Accounting Standards Update 2016-13
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2023
Change in accounting principle, accounting standards update, immaterial effect	true
Lexington Massachusetts facility
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 1,699	$ 1,699

- Definition

Date accounting standards update was adopted, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 405
-SubTopic 50
-Name Accounting Standards Codification
-Section 65
-Paragraph 1
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147477123/405-50-65-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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+ Details

Stockholders' Equity (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2023

Dec. 31, 2022

Equity [Abstract]

Schedule of Common Stock Shares Reserved for Future Issuance

The Company has reserved the following shares of common stock for future issuance as of March 31, 2023 and December 31, 2022:


	March 31, 2023		December 31, 2022
Stock options outstanding		5,600,088		5,742,053
Shares available for future grant under incentive plans		1,690,405		988,216

		7,290,493		6,730,269

The Company has reserved the following shares of common stock for future issuance as of December 31, 2022 and 2021:


	December 31, 2022		December 31, 2021
Stock options outstanding		5,742,053		6,830,037
Shares available for future grant under stock option plan		988,216		1,552,630

		6,730,269		8,382,667

Restructuring (Tables)

3 Months Ended

Mar. 31, 2023

Restructuring and Related Activities [Abstract]

Schedule of Restructuring-related charges

During the three months ended March 31, 2023, the following restructuring-related charges were included in the Consolidated Statement of Operations:


	Severance and other benefit-related costs		Accelerated depreciation charges		Accelerated hearing program charges		Total

Research and development	$	1,932	$	360	$	129	$	2,421
General and administrative		1,549		—		—		1,549

Total	$	3,481	$	360	$	129	$	3,970

Schdule of Changes to the liability for the restructuring


	Accelerated hearing program charges		Severance and other benefit-related costs		Total

Liability balance as of December 31, 2022	$	—	$	—	$	—
Net charges		129		3,329		3,458

Liability balance as of March 31, 2023	$	129	$	3,329	$	3,458

Prepaid Expenses and Other Current Assets (Tables)

12 Months Ended

Dec. 31, 2022

Prepaid Expense and Other Assets, Current [Abstract]

Summary of Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following:


	December 31, 2022		December 31, 2021
Rent and deposits	$	—	$	470
Research and development expenses		2,084		858
Accounts receivable		449		144
Insurance		1,608		2,384
Other		255		185

Total	$	4,396	$	4,041

Commitments and Contingencies	3 Months Ended	12 Months Ended
Commitments and Contingencies	Mar. 31, 2023	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	15. Commitments and contingencies Contract commitments The Company also enters into contracts in the normal course of business with contract researc h org anizations, contract manufacturing organizations, universities, and other third parties for preclinical research studies, clinical trials and testing and manufacturing services. These contracts generally do not contain minimum purchase commitments and are cancelable by the Company upon prior written notice although, purchase orders for clinical materials are generally non-cancelable. Payments due upon cancellation consist only of payments for services provided or expenses incurred, including non-cancelable obligations of the Company’s service providers, up to the date of cancellation or upon the completion of a manufacturing run. Guarantees The Company has identified the guarantees described below as disclosable, in accordance with ASC 460, Guarantees . As permitted under Delaware law, the Company indemnifies its officers and directors for certain events or occurrences while the officer or director is, or was, serving at the Company’s request in such capacity. The maximum potential amount of future payments the Company could be required to make is unlimited; however, the Company has directors’ and officers’ insurance coverage that should limit its exposure and enable it to recover a portion of any future amounts paid. The Company is a party to a number of agreements entered into in the ordinary course of business that contain typical provisions that obligate the Company to indemnify the other parties to such agreements upon the occurrence of certain events. Such indemnification obligations are usually in effect from the date of execution of the applicable agreement for a period equal to the applicable statute of limitations. The aggregate maximum potential future liability of the Company under such indemnification provisions is uncertain. The Company leases office space in Lexington, Massachusetts under a ten-year noncancelable operating lease. The $1,699 security deposit for this lease is classified as restricted cash as of March 31, 2023. The Company has standard indemnification arrangements under this lease that require it to indemnify the landlord against all costs, expenses, fines, suits, claims, demands, liabilities, and actions directly resulting from any breach, violation, or nonperformance of any covenant or condition of the lease. As of March 31, 2023, the Company had not experienced any losses related to these indemnification obligations, and no material claims with respect thereto were outstanding. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related reserves have been established. Legal Contingencies The Company accrues a liability for legal contingencies when it believes that it is both probable that a liability has been incurred and that the Company can reasonably estimate the amount of the loss. The Company reviews these accruals and adjusts them to reflect ongoing negotiations, settlements, rulings, advice of legal F-49 Table of Contents counsel and other relevant information. To the extent new information is obtained and the views on the probable outcomes of claims, suits, assessments, investigations or legal proceedings change, changes in the Company’s accrued liabilities would be recorded in the period in which such determination is made. In addition, in accordance with the relevant authoritative guidance, for any matters in which the likelihood of material loss is at least reasonably possible, the Company will provide disclosure of the possible loss or range of loss. If a reasonable estimate cannot be made, however, the Company will provide disclosure to that effect. The Company expenses legal costs as they are incurred. On June 3, 2021 and June 22, 2021, purported stockholders of the Company filed putative class action lawsuits in the U.S. District Court for the District of Massachusetts against the Company and the Company’s Chief Executive Officer, President, and Director, David Lucchino. On March 21, 2022, the two lawsuits were consolidated into a single lawsuit, Quinones et al. v. Frequency Therapeutics, Inc. et al. and on May 16, 2022, the Company’s Chief Development Officer, Dr. Carl LeBel, was added as a defendant. The plaintiffs alleged violations of Sections 10(b), 20(a) and Rule 10b5 of the Securities Exchange Act of 1934, as amended (the Exchange Act), due to allegedly false and misleading statements and omissions about the Company’s Phase 2a clinical trial (FX-322-202) for its product candidate FX-322 in the Company’s public disclosures between October 29, 2020 and March 22, 2021. The lawsuit sought, among other things, damages in connection with the Company’s allegedly artificially inflated stock price between October 29, 2020 and March 22, 2021 as a result of those allegedly false and misleading statements and omissions, as well as interest, attorneys’ fees and costs. The Company filed a motion to dismiss the Amended Complaint on July 15, 2022. This matter is at the very early stages of the legal process, and as a result, the Company is not able to estimate a range of possible loss. On March 29, 2023, the Company’s motion to dismiss was granted and the lawsuit was dismissed in its entirety. On April 27, 2023, Plaintiff filed a notice of appeal to the United States Court of Appeals for the First Circuit from the order dismissing the lawsuit. Since an estimate of the possible loss or range of loss cannot be made at this time, no accruals have been recorded as of March 31, 2023. On June 21, 2022, the Delaware Chancery Court dismissed a lawsuit brought by two purported stockholders against the Company and others. For previously reported information on this lawsuit, refer to Part I, Item 3, “Legal Proceedings” of the Company’s 2021 Form 10-K. On August 16, 2022, these same two purported stockholders of the Company filed a similar lawsuit in Delaware Superior Court against (i) the Company, (ii) Computershare Inc., and (iii) Computershare Trust Company, N.A., entitled The Gregory J. Parseghian Revocable Trust, et al. v. Frequency Therapeutics, Inc., et al. The lawsuit alleges causes of action against the Company for breach of the statutory duty of care, negligence, conversion, and unjust enrichment, based on allegations that actions were taken to prevent the purported stockholders from selling their shares in the Company. The Company intends to vigorously defend against all claims asserted in the lawsuit. The Company filed a motion to dismiss the complaint on November 14, 2022. This matter is at the very early stages of the legal process, and as a result, the Company is not able to estimate a range of possible loss. Since an estimate of the possible loss or range of loss cannot be made at this time, no accruals have been recorded as of March 31, 2023. On June 30, 2022, a purported stockholder of the Company filed a shareholder derivative complaint in the U.S. District Court for the District of Delaware purportedly on the Company’s behalf against members of the Company’s board of directors and the Company as a nominal defendant, entitled Dewey v. Cohen et. al. The complaint alleges (i) violations of Section 10(b) and Rule 10b5 of the Exchange Act, (ii) breach of fiduciary duty, (iii) aiding and abetting breach of fiduciary duty, (iv) unjust enrichment, and (v) waste of corporate assets. The claims are based on the same underlying allegations as the Quinones case (described above). The complaint seeks, among other things, monetary damages, interest, attorneys’ fees and costs. On September 27, 2022, this lawsuit was stayed pending final resolution of the Quinones case. This matter is at the very early stages of the legal process, and as a result, the Company is not able to estimate a range of possible loss. The Company’s board members are each party to an indemnification agreement with the Company that may require the Company to reimburse the board members for certain expenses and other costs related to this lawsuit. Since an estimate of the possible loss or range of loss cannot be made at this time, no accruals have been recorded as of March 31, 2023.	16. Commitments and contingencies Contract commitments The Company enters into contracts in the normal course of business with CROs, CMOs, universities, and other third parties for preclinical research studies, clinical trials and testing and manufacturing services. These contracts generally do not contain minimum purchase commitments and are cancelable by us upon prior written notice although, purchase orders for clinical materials are generally non-cancelable. Payments due upon cancellation consist only of payments for services provided or expenses incurred, including non-cancelable obligations of our service providers, up to the date of cancellation or upon the completion of a manufacturing run. Guarantees The Company has identified the guarantees described below as disclosable, in accordance with ASC 460, Guarantees . As permitted under Delaware law, the Company indemnifies its officers and directors for certain events or occurrences while the officer or director is, or was, serving at the Company’s request in such capacity. The maximum potential amount of future payments the Company could be required to make is unlimited; however, the Company has directors’ and officers’ insurance coverage that should limit its exposure and enable it to recover a portion of any future amounts paid. The Company is a party to a number of agreements entered into in the ordinary course of business that contain typical provisions that obligate the Company to indemnify the other parties to such agreements upon the occurrence of certain events. Such indemnification obligations are usually in effect from the date of execution of the applicable agreement for a period equal to the applicable statute of limitations. The aggregate maximum potential future liability of the Company under such indemnification provisions is uncertain. The Company leases office space in Lexington, Massachusetts under a ten-year noncancelable lease. The $1,699 security deposit for this lease is classified as restricted cash as of December 31, 2022. The Company exited the Woburn, Massachusetts facility in the second quarter of 2021. The Company has standard indemnification arrangements under these leases that require it to indemnify the landlord against all costs, expenses, fines, suits, claims, demands, liabilities, and actions directly resulting from any breach, violation, or nonperformance of any covenant or condition of the lease. As of December 31, 2022 and 2021, the Company had not experienced any losses related to these indemnification obligations, and no material claims with respect thereto were outstanding. The Company does not expect significant claims related to these indemnification obligations and, consequently, concluded that the fair value of these obligations is negligible, and no related reserves have been established. Legal Contingencies The Company accrues a liability for legal contingencies when it believes that it is both probable that a liability has been incurred and that the Company can reasonably estimate the amount of the loss. The Company reviews these accruals and adjusts them to reflect ongoing negotiations, settlements, rulings, advice of legal counsel and other relevant information. To the extent new information is obtained and the views on the probable outcomes of claims, suits, assessments, investigations or legal proceedings change, changes in the Company’s accrued liabilities would be recorded in the period in which such determination is made. In addition, in accordance with the relevant authoritative guidance, for any matters in which the likelihood of material loss is at least reasonably possible, the Company will provide disclosure of the possible loss or range of loss. If a reasonable estimate cannot be made, however, the Company will provide disclosure to that effect. The Company expenses legal costs as they are incurred. On June 3, 2021 and June 22, 2021, purported stockholders of the Company filed putative class action lawsuits in the U.S. District Court for the District of Massachusetts against the Company and the Company’s Chief Executive Officer, President, and Director, David Lucchino. On March 21, 2022, the two lawsuits were consolidated into a single lawsuit, Quinones et al. v. Frequency Therapeutics, Inc. et al . and on May 16, 2022, the Company’s Chief Development Officer, Dr. Carl LeBel, was added as a defendant. The plaintiffs allege violations of Sections 10(b), 20(a) and Rule 10b5 of the Securities Exchange Act of 1934, as amended (the Exchange Act), due to allegedly false and misleading statements and omissions about the Company’s Phase 2a clinical trial (FX-322-202) for its product candidate FX-322 in the Company’s public disclosures between October 29, 2020 and March 22, 2021. The lawsuit seeks, among other things, damages in connection with the Company’s allegedly artificially inflated stock price between October 29, 2020 and March 22, 2021 as a result of those allegedly false and misleading statements and omissions, as well as interest, attorneys’ fees and costs. The Company intends to vigorously defend against all claims asserted in the lawsuit. The Company filed a motion to dismiss the Amended Complaint on July 15, 2022. This matter is at the very early stages of the legal process, and as a result, the Company is not able to estimate a range of possible loss. Since an estimate of the possible loss or range of loss cannot be made at this time, no accruals have been recorded as of December 31, 2022. On June 21, 2022, the Delaware Chancery Court dismissed a lawsuit brought by two purported stockholders against the Company and others. For previously reported information on this lawsuit, refer to Part I, Item 3, “Legal Proceedings” of the Company’s 2021 Form 10-K. On August 16, 2022, these same two purported stockholders of the Company filed a similar lawsuit in Delaware Superior Court against (i) the Company, (ii) Computershare Inc., and (iii) Computershare Trust Company, N.A., entitled The Gregory J. Parseghian Revocable Trust , et al. v. Frequency Therapeutics, Inc., et al. The lawsuit alleges causes of action against the Company for breach of the statutory duty of care, negligence, conversion, and unjust enrichment, based on allegations that actions were taken to prevent the purported stockholders from selling their shares in the Company. The Company intends to vigorously defend against all claims asserted in the lawsuit. This matter is at the very early stages of the legal process, and as a result, the Company is not able to estimate a range of possible loss. Since an estimate of the possible loss or range of loss cannot be made at this time, no accruals have been recorded as of December 31, 2022. On June 30, 2022, a purported stockholder of the Company filed a shareholder derivative complaint in the U.S. District Court for the District of Delaware purportedly on the Company’s behalf against members of the Company’s board of directors and the Company as a nominal defendant, entitled Dewey v. Cohen et. al. The complaint alleges (i) violations of Section 10(b) and Rule 10b5 of the Exchange Act, (ii) breach of fiduciary duty, (iii) aiding and abetting breach of fiduciary duty, (iv) unjust enrichment, and (v) waste of corporate assets. The claims are based on the same underlying allegations as the Quinones case (described above). The complaint seeks, among other things, monetary damages, interest, attorneys’ fees and costs. On September 27, 2022, this lawsuit was stayed pending resolution of the Quinones case. This matter is at the very early stages of the legal process, and as a result, the Company is not able to estimate a range of possible loss. The Company’s board members are each party to an indemnification agreement with the Company that may require the Company to reimburse the board members for c er tain expenses and other costs related to this lawsuit. Since an estimate of the possible loss or range of loss cannot be made at this time, no accruals have been recorded as of December 31, 2022.

Commitments and Contingencies - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessee Lease Description [Line Items]
Losses related to indemnification obligations	$ 0	$ 0	$ 0
Legal contingencies, accruals recorded		0
Lexington Massachusetts Facility
Lessee Lease Description [Line Items]
Operating lease term	10 years
Security deposit classified as restricted cash	$ 1,699,000	$ 1,699,000

Leases - Schedule of Leases (Details)	Dec. 31, 2022
Leases [Abstract]
Weighted-average remaining lease term	8 years 4 months 24 days
Weighted-average discount rate	8.50%