0000950170-22-003655 | 10-K | XBRL Viewer | Frequency Therapeutics INC

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 79,635	$ 220,341
Short-term marketable securities	51,072
Prepaid expenses and other current assets	4,041	4,723
Total current assets	134,748	225,064
Long-term marketable securities	11,719
Property and equipment, net	5,522	7,287
Right of use assets	31,350	30,551
Restricted cash	1,699	1,820
Long-term assets	320
Total assets	185,358	264,722
Current liabilities:
Accounts payable	2,748	5,506
Accrued expenses	6,101	6,663
Deferred revenue		14,068
Lease liabilities	1,747	397
Term loan, current portion	833
Total current liabilities	11,429	26,634
Lease liabilities, net of current portion	28,851	30,597
Term Loan, net of current portion	14,167	15,000
Long-term liabilities	87
Total liabilities	54,534	72,231
Stockholders’ equity:
Preferred stock, $0.001 par value; 10,000,000 shares authorized, no shares issued or outstanding at December 31, 2021 and December 31, 2020, respectively	0	0
Common stock, $0.001 par value; 200,000,000 shares authorized, 34,611,213 and 33,964,000 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively	35	34
Additional paid-in capital	310,936	287,829
Accumulated other comprehensive (loss) income	(62)	27
Accumulated deficit	(180,085)	(95,399)
Total stockholders’ equity	130,824	192,491
Total liabilities and stockholders’ equity	$ 185,358	$ 264,722

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, authorized shares	10,000,000	10,000,000
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, authorized shares	200,000,000	200,000,000
Common stock, issued shares	34,611,213	33,964,000
Common stock, outstanding shares	34,611,213	33,964,000

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Revenue	$ 14,068	$ 36,984
Operating expenses:
Research and development	60,923	37,415
General and administrative	37,176	27,119
Total operating expenses	98,099	64,534
Loss from operations	(84,031)	(27,550)
Interest income	397	994
Interest expense	(764)	0
Realized (loss) gain on investments	(23)	84
Foreign exchange gain (loss)	16	(4)
Other expense, net	(266)	0
Loss before income taxes	(84,671)	(26,476)
Income taxes	(15)	(35)
Net loss	$ (84,686)	$ (26,511)
Net loss per share-basic and diluted	$ (2.47)	$ (0.82)
Weighted-average shares of common stock outstanding-basic and diluted	34,351,274	32,253,227

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (84,686)	$ (26,511)
Other comprehensive loss:
Unrealized loss on marketable securities	(89)	(27)
Total comprehensive loss	(89)	(27)
Comprehensive loss	$ (84,775)	$ (26,538)

- Definition

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

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+ Details

Consolidated Statement of Stockholders Equity - USD ($) $ in Thousands	Total	Common Stock	Additional-paid in Capital	Accumulated Other Comprehensive Income	Accumulated Deficit
Beginning Balance at Dec. 31, 2019	$ 167,358	$ 31	$ 236,161	$ 54	$ (68,888)
Beginning Balance (in shares) at Dec. 31, 2019		30,844,507
Stock-based compensation expense	9,983		9,983
Issuance of common stock upon exercise of stock options	1,545	$ 1	1,544
Issuance of common stock upon exercise of options (in shares)		769,385
Issuance of common stock in Private Placement, net	40,143	$ 2	40,141
Issuance of common stock in Private Placement, net (in shares)		2,350,108
Other comprehensive income loss	(27)			(27)
Net loss	(26,511)				(26,511)
Ending Balance at Dec. 31, 2020	$ 192,491	$ 34	287,829	27	(95,399)
Ending Balance (in shares) at Dec. 31, 2020	33,964,000	33,964,000
Stock-based compensation expense	$ 21,750		21,750
Purchase under Employee Stock Purchase Plan	60		60
Purchase under Employee Stock Purchase Plan (in shares)		7,064
Issuance of common stock upon exercise of stock options	1,298	$ 1	1,297
Issuance of common stock upon exercise of options (in shares)		642,314
Forfeiture of restricted stock (in shares)		(2,165)
Other comprehensive income 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

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Cash flows from operating activities:
Net loss	$ (84,686)	$ (26,511)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	21,750	9,983
Depreciation expense	2,775	1,146
Non-cash lease expense	1,066	434
Non-cash interest expense	347
Loss on disposal of assets	16
Changes in operating assets and liabilities:
Prepaid expenses and other assets	(173)	(626)
Accounts payable	(2,292)	4,287
Deferred revenue	(14,068)	(36,984)
Accrued expenses	(794)	3,083
Net cash used in operating activities	(76,059)	(45,188)
Cash flows from investing activities:
Purchases of property and equipment	(2,914)	(6,671)
Purchase of marketable securities	(92,445)	(26,345)
Redemption of marketable securities	29,233	43,418
Net cash (used in) provided by investing activities	(66,126)	10,402
Cash flows from financing activities:
Proceeds from issuance of common stock	1,298	1,545
Proceeds from Employee Stock Purchase Plan	60
Proceeds from Private Placement, net of issuance costs		40,143
Proceeds from Term Loan		15,000
Net cash provided by financing activities	1,358	56,688
Net (decrease) increase in cash, cash equivalents, and restricted cash	(140,827)	21,902
Cash, cash equivalents, and restricted cash at beginning of period	222,161	200,259
Cash, cash equivalents, and restricted cash at end of period	81,334	222,161
Supplemental disclosures:
Cash paid for interest	703
Right-of-use assets in exchange for lease liabilities		31,335
Purchases of property and equipment included in accounts payable and accrued expenses		$ 2,145

Organization

12 Months Ended

Dec. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization

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 clinical-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 the sale of its capital stock, convertible notes and amounts received under a collaboration agreement. The Company has incurred recurring losses since its inception. In addition, as of December 31, 2021, the Company had an accumulated deficit of $180,085. 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.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

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 income or loss, including net income or loss, are reported in the financial statements in the period in which they are recognized. Other comprehensive income or loss is defined as the change in equity during a period from transactions and other events and circumstances from non-owner sources. Net income (loss) and other comprehensive income (loss) are reported net of any related tax effect to arrive at comprehensive income (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, 2021 and 2020 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, views the Company’s operations and manages its business as a single operating segment, which is in the business of discovering and developing small molecule drugs that activate progenitor cells within the body to create healthy tissue.

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, 2021 and 2020 the Company recorded $16 of foreign currency exchange gains and $4 of foreign currency exchange losses, 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, 2021 and 2020 consists entirely of cash and money market funds.

Restricted cash

The Company has $1,700 of restricted cash as of December 31, 2021 which represents a security deposit on the Company's Lexington, Massachusetts facility. The $1,800 of restricted cash at December 31, 2020 represented the security deposit on the Lexington, Massachusetts facility as well as a $100 security deposit on the Company's previous Woburn, 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 (loss) gain on investments.

Concentration of credit risk and off-balance sheet risk

Financial instrument 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 values of other current assets, accounts payable, and accrued expenses approximate their fair values due to the short-term nature of these assets and liabilities. The fair value of the Company’s Term Loan is not materially different from the carrying value as presented.

Property and equipment, net

Property and equipment consist of lab equipment, computer equipment, furniture and office equipment and leasehold improvements 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
Leasehold improvements		Shorter of the estimated useful life or lease term

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, 2021 and 2020.

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, pre-clinical 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 elected to early adopt ASC 842, Leases (ASC 842) as of January 1, 2020 and elected the transition method under ASU 2016-02 whereby the Company records a right-to-use asset and a lease liability on the consolidated balance sheet for all leases with terms longer than 12 months. The Company also elected to apply the package of practical expedients intended to ease transition. Accordingly, the Company has only applied ASC 842 to leases existing at January 1, 2020. The Company determines if an arrangement is, or contains, a lease at inception. Operating leases are included in operating lease right-of-issue (“ROU”) assets, other current liabilities, and operating lease liabilities on the consolidated balance sheets.

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 lease 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 leases do 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 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 new 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, 2021 and 2020, the Company has concluded that a full valuation allowance is necessary for its deferred tax assets (see Note 11).

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 years ended December 31, 2021 and 2020 since all potential shares of common stock instruments are anti-dilutive as a result of the loss for such periods.

The Company’s convertible preferred stock contractually entitled the holders of such shares to participate in dividends but did not contractually require the holders of such shares to participate in losses of the Company. Accordingly, in periods in which the Company reported a net loss, such losses are not allocated to such participating securities. In periods where the Company reported a net loss attributable to common stockholders, diluted net loss per share is the same as basic net loss per share, since dilutive shares of common stock are not assumed to have been issued if their effect is anti-dilutive. The Company reported a net loss attributable to common stockholders for the years ended December 31, 2021 and 2020.

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


	Year Ended December 31,
	2021			2020
Numerator:
Net loss	$	(84,686	)	$	(26,511	)
Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		34,351,274			32,253,227
Net loss per share-basic and diluted	$	(2.47	)	$	(0.82	)

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


	Year Ended December 31,
	2021		2020
Unvested restricted common stock		—		3,093
Unvested restricted stock units		626,300		—
Outstanding stock options		6,830,037		6,816,798
Total		7,456,337		6,819,891

Recently adopted accounting pronouncements

In August 2018, the FASB issued ASU No. 2018-15, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Customer's Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That is a Service Contract. This standard addresses the accounting for implementation costs incurred by a customer in a cloud computing arrangement that is a service contract and also adds certain disclosure requirements related to implementation costs incurred for internal-use software and cloud computing arrangements. The amendment aligns the requirements for capitalizing implementation costs incurred in a cloud computing arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The Company adopted this standard on January 1, 2021, using a prospective approach. The adoption of this new standard did not have a material impact on the consolidated financial statements.

In December 2019, the FASB issued ASU 2019-12 amending accounting guidance that simplifies the accounting for income taxes, as part of its initiative to reduce complexity in the accounting standards. The amendments eliminate certain exceptions related to the approach for intraperiod tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. The amendments also clarify and simplify other aspects of the accounting for income taxes. The Company adopted this standard on January 1, 2021 and it did not have a material impact on the consolidated financial statements.

Recently issued 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. This standard will become effective for the Company on January 1, 2023. The Company is still evaluating the impact of this standard on its consolidated financial statements.

Fair Value Measurements

12 Months Ended

Dec. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements

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, 2021 and 2020 are summarized as follows:


		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


		December 31, 2020
	Fair Value	Amortization		Unrealized		Fair Market
	Hierarchy	Cost		Gain		Value
Money market funds	Level 1	$	214,522	$	27	$	214,549
		$	214,522	$	27	$	214,549

- 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

Prepaid Expenses and Other Current Assets

12 Months Ended

Dec. 31, 2021

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,		December 31,
	2021		2020
Rent and deposits		470		—
Research and development expenses		858		1,729
Accounts receivable		144		340
Insurance		2,384		2,552
Other		185		102
Total	$	4,041	$	4,723

Property and Equipment

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property and Equipment

5. Property and equipment

Property and equipment include the following:


	December 31,			December 31,
	2021			2020
Lab equipment	$	6,177		$	4,166
Furniture and office equipment		3,238			283
Software		291			291
Leasehold improvements		-			1,419
Construction in progress		-			4,340
Total		9,706			10,499
Accumulated depreciation		(4,184	)		(3,212	)
Property and equipment, net	$	5,522		$	7,287

The Company recognized $2,775 and $1,146 of depreciation expense for the years ended December 31, 2021 and 2020, respectively.

Accrued Expenses

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Accrued Expenses

6. Accrued expenses

Accrued expenses consist of the following:


	December 31,		December 31,
	2021		2020
Payroll and employee related expenses	$	4,375	$	5,062
Professional fees		767		647
Third-party research and development expenses		840		874
Other		119		80
Total	$	6,101	$	6,663

Debt

12 Months Ended

Dec. 31, 2021

Debt Disclosure [Abstract]

Debt

7. Debt

On December 11, 2020, the Company entered into a Loan and Security Agreement (the “Loan Agreement”) with a commercial bank for a Term Loan with a principal balance of $15,000. The Company will make 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 (the “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, 2021 was 4.75%. Interest related to the Loan Agreement was $764 for the year ended December 31, 2021 and immaterial for the year ended December 31, 2020.

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 recording the final payment as interest expense 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1I
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1C
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1E
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1B
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stockholders' Equity

12 Months Ended

Dec. 31, 2021

Equity [Abstract]

Stockholders' Equity

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, 2021.

Common stock

The Company has authorized 200,000,000 shares of $0.001 par value common stock of which 34,611,213 were issued and outstanding as of December 31, 2021. 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, 2021 and 2020:


	December 31,		December 31,
	2021		2020
Stock options outstanding		6,830,037		6,816,798
Shares available for future grant under stock option plan		1,552,630		1,475,923
		8,382,667		8,292,721

Equity Offerings

In July 2020, the Company completed a private placement of common stock to new and existing investors, or the Private Placement. In the Private Placement, the Company issued and sold 2,350,108 shares of common stock at a purchase price of $18.00 per share. The Company received approximately $40,100 in net proceeds, after deducting placement agent fees and other offering expenses. In connection with the Private Placement, the Company entered into a Registration Rights Agreement, or the Registration Rights Agreement, with the investors purchasing shares in the Private Placement. Pursuant to the Registration Rights Agreement, the Company filed a registration statement with the Securities and Exchange Commission, or the SEC, which was declared effective on September 3, 2020, registering the resale of the shares sold in the Private Placement.

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. 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, 2021.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: 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 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Stock-based Compensation

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock-based Compensation

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, 2021, 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 (“the “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		Weighted average remaining contractual term (in years)		Aggregate intrinsic value
Outstanding as of December 31, 2019		5,968,672		$	5.21		9.08	$	73,561
Granted		1,645,859			24.22		9.30		—
Exercised		(769,385	)		1.99		—	$	16,667
Forfeited		(28,348	)		16.38		—		—
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		$	14.72		7.76	$	6,987
Options exercisable as of December 31, 2021		3,993,231		$	9.77		7.34	$	6,275
Options unvested as of December 31, 2021		2,836,806		$	21.70		8.36	$	712

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:


	December 31,			December 31,
	2021			2020
Risk-free interest rate		0.5	%		1.1	%
Expected term (in years)		6.0			6.0
Expected volatility		79.8	%		79.1	%
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, 2021 and 2020 was $22.39 and $16.41 respectively.

The total grant date fair value of options vested during the years ended December 31, 2021 and 2020 was $16,304 and $7,907, respectively.

Restricted common stock

The Company issued common stock to founders, employees and advisors which was subject to vesting over four years. If any of these individuals ceased to be employed or to provide services to the Company prior to vesting, the Company had the right to repurchase any unvested Common Stock at the price paid by the holder.

A summary of the status of restricted common stock as of December 31, 2021 and 2020 is presented below:


	Number of shares			Weighted average fair value
Unvested, December 31, 2020		3,093		$	1.75
Awarded		—			—
Vested		(928	)		1.75
Forfeited		(2,165	)		1.75
Unvested, December 31, 2021		—		$	-

The total value of restricted stock awards that vested during the years ended December 31, 2021 and 2020, based on estimated fair values of the stock underlying the restricted stock awards was $2 and $20, respectively.

Restricted stock units

In April 2021, the Company issued restricted stock units to employees which will vest in equal installments in the first quarter of 2022 and the third quarter of 2022.

A summary of the status of restricted stock units as of December 31, 2021 and 2020 is presented below:


	Number of shares			Weighted average fair value

Unvested, December 31, 2020		—		$	-
Awarded		800,000			9.54
Vested		—			—
Forfeited		(173,700	)		9.54
Unvested, December 31, 2021		626,300		$	9.54

Stock-based compensation

Stock-based compensation expense of $21,750 and $9,983 for the years ended December 31, 2021 and 2020 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, 2021 and 2020, total unrecognized stock-based compensation expense relating to unvested stock options, restricted stock awards, and restricted stock units was $39,112 and $31,006, respectively. This amount is expected to be recognized over a weighted-average period of 2.49 years and 3.08 years, respectively.

Employee Stock Purchase Plan

12 Months Ended

Dec. 31, 2021

Retirement Benefits [Abstract]

Employee Stock Purchase Plan

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 (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. 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. As of December 31, 2021, a total of 956,021 shares remain for future offering periods. The Company's second offering period of 2021 concluded on December 31, 2021 with the purchase of 31,832 shares in January 2022 related to this offering.

Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

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 we have not recorded any net tax benefit due to uncertainty around utilizing these tax attributes within the respective carryforward periods.

As of December 31, 2021, the Company had federal net operating loss carryforwards of approximately $149,071 and Massachusetts state operating loss carryforwards of approximately $83,467 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 $126,672 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 2041. As of December 31, 2021, the Company also had federal and Massachusetts research and development tax credit carryforwards of $5,241 and $2,071, respectively, which are available to offset federal and state tax liabilities through 2041 and 2036, 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 Internal Revenue Code of 1986, as amended, 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, results from transactions increasing the ownership of certain shareholders or public groups in the stock of a corporation by more than 50% over a 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. After the Section 382 limitations, 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-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 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. 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 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, 2021 and 2020 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 $50,931 and $26,995 as of December 31, 2021 and 2020 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, 2021 and 2020.

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 income for the years ended December 31, 2021 and 2020 is as follows:


	2021			2020
Domestic	$	(84,624	)	$	(25,744	)
Foreign		(47	)		(732	)
Total	$	(84,671	)	$	(26,476	)

The Company’s provision at December 31, 2021 and 2020 consist of the following:


	2021		2020
Current:
Federal	$	-	$	35
State		15		-
Foreign		-		-
Total current	$	15	$	35
Deferred:
Federal		-		-
State		-		-
Foreign		-		-
Total Deferred	$	-	$	-
Total provision (benefit)	$	15	$	35

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, 2021 and 2020 is as follows:


	2021			2020
U.S federal statutory income tax rate		21.0	%		21.0	%
Permanent differences		—			(0.2	)
State income taxes, net of federal benefit		2.7			3.0
Research and development tax credits		3.6			11.2
Stock compensation deductions		1.6			5.1
Other items		(0.7	)		0.6
Change in deferred tax asset valuation allowance		(28.2	)		(40.7	)
Effective income tax rate	—%			—%

The Company’s deferred tax assets at December 31, 2021 and 2020 consist of the following:


	2021			2020
Net operating loss carryforwards	$	36,590		$	17,885
Research and development tax credits		7,026			3,992
Intangibles		392			360
Stock compensation		6,554			850
Accrued expenses		107			-
Deferred revenue		-			3,606
Other		176			142
Fixed assets		265			56
Lease liability		7,269			7,285
Right of use asset		(7,448	)		(7,181	)
Total deferred tax asset		50,931			26,995
Valuation allowance		(50,931	)		(26,995	)
Net deferred tax assets	$	—		$	—

- 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
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Research and License Agreements

12 Months Ended

Dec. 31, 2021

Research and Development [Abstract]

Research and License Agreements

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 III 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 $6 and $1,980 from MIT under the MIT Policy during the years ended December 31, 2021 and 2020, respectively. Refer to Note 17 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 II clinical trial (or equivalent) for a CALIBR Licensed Product by December 31, 2023 and (ii) initiate a Phase III clinical trial (or equivalent) for a CALIBR Licensed Product by December 31, 2025. EW do not have the right to control prosecution of the in-licensed patent applications , and our 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 are 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.

The Scripps Research Institute

In September 2018, the Company entered into a Research Funding and Option Agreement, or the Scripps option agreement, with Scripps (CALIBR is a division of Scripps), under which the Company provided funding to Scripps to pursue certain MS research activities on selected targets. In the same agreement, the Company was granted an exclusive option to acquire an exclusive, sublicensable, worldwide license under certain intellectual property arising from the MS research activities on the selected targets. The Scripps option agreement, including the MS research activities and the exclusive option, terminated on December 31, 2021. The CALIBR License remains active.

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 II trial by December 31, 2020. The Company is still subject to a milestone timeline obligation to dose a first subject in a Phase III 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.

Cambridge Enterprise Limited

In December 2019, we entered into an Exclusive Patent License Agreement ( the “Cambridge License”) with Cambridge Enterprise Limited (the technology transfer arm of the University of Cambridge) (“Cambridge”) under which we received an exclusive worldwide royalty-bearing license to certain patent rights to make, have made, sell, offer to sell and import products, or the (the “Cambridge License Product”) which incorporate licensed technology for the treatment of demyelinating diseases. We also have the right to grant sublicenses under the Cambridge License. Cambridge reserves the right to use for itself (as well as for the inventors and the funder) to grant nonexclusive licenses to other academic institutions for any academic publication, research and teaching and clinical patient care.

The Company has agreed to use diligent and good faith efforts to develop and commercially exploit at least one Cambridge Licensed Product. Upon entering into the Cambridge License, the Company made a $50 license fee payment. The Company is obligated to pay an annual license fee of $50. The Company is also obligated to make milestone payments up to $10,500 on each Cambridge License Product. In addition, the Company has agreed to pay a low single-digit royalty on products that incorporate the licensed patent rights, subject to offset in certain circumstances.

The Cambridge License continues in effect on a country-by-country basis until the expiration or revocation, without right of further appeal, of all licensed issued patents and filed patent applications, unless terminated earlier. We have the right to terminate for any reason upon 90 days’ prior to written notice. Each party has the right to terminate immediately if the other party ceases to carry on its business. Either party may also terminate the Cambridge License for material breach if such breach remains uncured for 30 days. Cambridge may also terminate the Cambridge License if we fail to diligently develop and commercially exploit at least one Cambridge Licensed Product or we or our affiliates or sub-licenses commence any action against Cambridge to declare or render any claim of the licensed patent rights invalid, unpatentable, unenforceable, or not infringed.

Department of Defense

In June 2018, the Company received a grant (the Grant) from the Department of Defense (DoD) under which the Company is receiving funding to further the Company’s research and development of a therapeutic drug to treat hearing loss. The Company received funding of $1,596 over two years from the date of the Grant. The Company has determined that the DoD is not considered a customer under ASC 606, therefore funding received from the DoD under the Grant is recorded as a reduction of research and development expenses. The Company has recorded $323 as a reduction in research and development expenses for the year ended December 31, 2020. No funding was received in 2021.

Collaboration Agreement

12 Months Ended

Dec. 31, 2021

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.

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, is 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 recognized over such period. The completion date of the Phase 2a clinical trial (FX-322-202) and the total research and development costs incurred in performing the trial was June 30, 2021. As such, the Company recognized the $80,000 upfront fee 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 $80,000 upfront payment received from Astellas in July 2019 was initially recorded as deferred revenue and was recognized as revenue according to the policy described above. As of June 30, 2021, the Company completed its performance

obligation with respect to the upfront payment and, accordingly, recognized all remaining revenue related to the Astellas Agreement.

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, 2021 and 2020, the Company invoiced Astellas $885 and $1,046 for joint costs.

Leases

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Leases

14. Leases

In 2016, the Company entered into a five-year operating lease for the Company’s primary office and laboratory space in Woburn, Massachusetts. In November 2019, this lease was amended to add additional laboratory and office space as well as extend the termination date for all spaces to February 2025. The lease and amendment do not contain any material residual value guarantees or material restrictive covenants.

On December 11, 2020, the Company entered into an Agreement for Termination of Lease and Voluntary Surrender of Premises (the “Lease Termination Agreement”) with ARE-MA Region No. 20, LLC (the “Landlord”). 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.

As consideration for the Landlord’s agreement to enter into the Lease Termination Agreement and accelerate the expiration date of the term of the Lease, the Company has agreed to pay to Landlord a fee of approximately $200.

On January 7, 2020 the Company entered into an indenture of lease (the “Lexington Lease”) with HCP/KING 75 Hayden LLC, for the lease of approximately 61,307 square feet of rentable area in Lexington, Massachusetts or (the “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 continues to lease a small office space in Connecticut.

The Company's rent expense for the years ended December 31, 2021 and 2020 was $4,960 and $835, respectively.


Other information	December 31, 2021
Weighted-average remaining operating lease term	9.4 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, 2021.


2022		4,159
2023		4,284
2024		4,412
2025		4,545
2026		4,681
Thereafter		22,389
Total minimum lease payments		44,470
Less: amount of lease payments representing interest		(13,872	)
Present value of future lease payments		30,598
Less: current lease liabilities		(1,747	)
Noncurrent lease liabilities	$	28,851

Future aggregate minimum payments under the noncancelable operating leases and short term leases, including the Lexington, MA lease and Connecticut lease, which is not subject to ASC 842, as of December 31, 2021 are as follows:


2022	$	4,161
2023		4,284
2024		4,412
2025		4,545
2026		4,681
2027 and beyond		22,388
Total minimum lease payments	$	44,471

Commitments and Contingencies

12 Months Ended

Dec. 31, 2021

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

15. Commitments and contingencies

Contract commitments

The Company has contracted with a research institution to provide research for a therapeutic drug to treat multiple sclerosis. In September 2020, the Company extended the term of this contract through December 2021. As consideration for this extension, the Company committed to total payments of $600 through December 2021.

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 $1,700 security deposit for this lease is classified as restricted cash as of December 31, 2021. 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, 2021 and 2020, 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 entitled Evans v. Frequency Therapeutics, Inc. et al. and Hingston v. Frequency Therapeutics, Inc. et al., respectively. The lawsuits allege violations of Section 10(b), 20(a) and Rule 10b5 of the Securities Exchange Act of 1934, as amended, 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 November 16, 2020 and March 22, 2021. The lawsuits seek, among other things, damages in connection with the Company’s allegedly artificially inflated stock price between November 16, 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. These matters are 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 is vigorously defending against all claims asserted in both lawsuits. The Company has not yet filed a responsive pleading. 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, 2021.

On June 24, 2021, two purported stockholders of the Company filed a lawsuit in the Court of Chancery of the State of Delaware against (i) the Company, (ii) the Company’s Chief Executive Officer, President, and Director, David Lucchino, (iii) Computershare Inc., and (iv) Computershare Trust Company, N.A., entitled The Gregory J. Parseghian Revocable Trust, et al. v. Frequency Therapeutics, Inc., et al. The lawsuit asserts causes of action against the Company of conversion and, in the alternative, unjust enrichment, and against Mr. Lucchino for breach of the fiduciary duty of loyalty, based on allegations that actions were taken to prevent the purported stockholders from selling their shares in the Company. The lawsuit seeks monetary damages, as well as interest, attorneys’ fees and costs, against all defendants. 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. We are vigorously defending against all claims asserted and have filed a motion to dismiss the complaint, which remains pending. 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, 2021.

Employee Benefit Plan

12 Months Ended

Dec. 31, 2021

Retirement Benefits [Abstract]

Employee Benefit Plan

16. Employee benefit plan

Employees of the Company are eligible to participate in the Company’s 401(k) retirement plan (the “401(k) Plan”). Participants 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, 2021 and 2020, the Company made matching contributions of $723 and $400, respectively.

- Definition

The entire disclosure for retirement benefits.

+ References

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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Related Party Transactions

12 Months Ended

Dec. 31, 2021

Related Party Transactions

17. Related party transactions

As disclosed in Note 12, 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 $6 and $1,980 from MIT under the MIT Policy during the years ended December 31, 2021 and 2020, respectively.

The Company's lease for its Woburn, Massachusetts facility, terminated in May 2021 as disclosed in Note 14, was with an entity affiliated with one of the Company's directors and shareholders.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Basis of Presentation

Basis of presentation

Principles of Consolidation

Principles of consolidation

Use of Estimates

Use of estimates

Comprehensive loss

economic events other than those with stockholders which for the years ended December 31, 2021 and 2020 consist of unrealized loss on marketable securities.

Segment Information

Segment information

Foreign Currency

Foreign currency

Cash and Cash Equivalents

Cash and cash equivalents

Restricted Cash

Restricted cash

Marketable Securities

Marketable securities

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

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
Leasehold improvements		Shorter of the estimated useful life or lease term

Impairment of Long-Lived Assets

Impairment of long-lived assets

Research and Development Costs and Accruals

Research and development costs and accruals

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

Collaborative Arrangements

Collaborative arrangements

The Company has entered into a collaboration arrangement with Astellas Pharma Inc. (“Astellas”), as further described in Note 13 of notes to consolidated financial statements.

Revenue Recognition

Revenue recognition

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

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,
	2021			2020
Numerator:
Net loss	$	(84,686	)	$	(26,511	)
Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		34,351,274			32,253,227
Net loss per share-basic and diluted	$	(2.47	)	$	(0.82	)


	Year Ended December 31,
	2021		2020
Unvested restricted common stock		—		3,093
Unvested restricted stock units		626,300		—
Outstanding stock options		6,830,037		6,816,798
Total		7,456,337		6,819,891

Recently Adopted Accounting Pronouncements

Recently adopted accounting pronouncements

Recently issued accounting pronouncements

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Property And Equipment


		Estimated useful life
Lab equipment		3 years
Software		3 years
Furniture and office equipment		3 years
Leasehold improvements		Shorter of the estimated useful life or lease term

Schedule of Basic and Diluted Net Loss per Share

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


	Year Ended December 31,
	2021			2020
Numerator:
Net loss	$	(84,686	)	$	(26,511	)
Denominator:
Weighted-average shares of common stock outstanding-basic and diluted		34,351,274			32,253,227
Net loss per share-basic and diluted	$	(2.47	)	$	(0.82	)

Computation of Diluted Net Loss per Share


	Year Ended December 31,
	2021		2020
Unvested restricted common stock		—		3,093
Unvested restricted stock units		626,300		—
Outstanding stock options		6,830,037		6,816,798
Total		7,456,337		6,819,891

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2021

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, 2021 and 2020 are summarized as follows:


		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


		December 31, 2020
	Fair Value	Amortization		Unrealized		Fair Market
	Hierarchy	Cost		Gain		Value
Money market funds	Level 1	$	214,522	$	27	$	214,549
		$	214,522	$	27	$	214,549

Prepaid Expenses and Other Current Assets (Tables)

12 Months Ended

Dec. 31, 2021

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,		December 31,
	2021		2020
Rent and deposits		470		—
Research and development expenses		858		1,729
Accounts receivable		144		340
Insurance		2,384		2,552
Other		185		102
Total	$	4,041	$	4,723

Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

Property and equipment include the following:


	December 31,			December 31,
	2021			2020
Lab equipment	$	6,177		$	4,166
Furniture and office equipment		3,238			283
Software		291			291
Leasehold improvements		-			1,419
Construction in progress		-			4,340
Total		9,706			10,499
Accumulated depreciation		(4,184	)		(3,212	)
Property and equipment, net	$	5,522		$	7,287

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Schedule of Accrued Expenses

Accrued expenses consist of the following:


	December 31,		December 31,
	2021		2020
Payroll and employee related expenses	$	4,375	$	5,062
Professional fees		767		647
Third-party research and development expenses		840		874
Other		119		80
Total	$	6,101	$	6,663

Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2021

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 December 31, 2021 and 2020:


	December 31,		December 31,
	2021		2020
Stock options outstanding		6,830,037		6,816,798
Shares available for future grant under stock option plan		1,552,630		1,475,923
		8,382,667		8,292,721

Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2021

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

Summary of Stock Option Activity under 2014 Plan and 2019 Plan

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		Weighted average remaining contractual term (in years)		Aggregate intrinsic value
Outstanding as of December 31, 2019		5,968,672		$	5.21		9.08	$	73,561
Granted		1,645,859			24.22		9.30		—
Exercised		(769,385	)		1.99		—	$	16,667
Forfeited		(28,348	)		16.38		—		—
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		$	14.72		7.76	$	6,987
Options exercisable as of December 31, 2021		3,993,231		$	9.77		7.34	$	6,275
Options unvested as of December 31, 2021		2,836,806		$	21.70		8.36	$	712

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:


	December 31,			December 31,
	2021			2020
Risk-free interest rate		0.5	%		1.1	%
Expected term (in years)		6.0			6.0
Expected volatility		79.8	%		79.1	%
Expected dividend yield		0.0	%		0.0	%

Restricted Common Stock

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

Summary of Status of Restricted Common Stock

A summary of the status of restricted common stock as of December 31, 2021 and 2020 is presented below:


	Number of shares			Weighted average fair value
Unvested, December 31, 2020		3,093		$	1.75
Awarded		—			—
Vested		(928	)		1.75
Forfeited		(2,165	)		1.75
Unvested, December 31, 2021		—		$	-

Restricted Stock Units

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

Summary of Status of Restricted Common Stock

A summary of the status of restricted stock units as of December 31, 2021 and 2020 is presented below:


	Number of shares			Weighted average fair value

Unvested, December 31, 2020		—		$	-
Awarded		800,000			9.54
Vested		—			—
Forfeited		(173,700	)		9.54
Unvested, December 31, 2021		626,300		$	9.54

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of Reconciliation Pre-tax Income

A reconciliation of the Company’s pre-tax income for the years ended December 31, 2021 and 2020 is as follows:


	2021			2020
Domestic	$	(84,624	)	$	(25,744	)
Foreign		(47	)		(732	)
Total	$	(84,671	)	$	(26,476	)

Schedule of Provision

The Company’s provision at December 31, 2021 and 2020 consist of the following:


	2021		2020
Current:
Federal	$	-	$	35
State		15		-
Foreign		-		-
Total current	$	15	$	35
Deferred:
Federal		-		-
State		-		-
Foreign		-		-
Total Deferred	$	-	$	-
Total provision (benefit)	$	15	$	35

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, 2021 and 2020 is as follows:


	2021			2020
U.S federal statutory income tax rate		21.0	%		21.0	%
Permanent differences		—			(0.2	)
State income taxes, net of federal benefit		2.7			3.0
Research and development tax credits		3.6			11.2
Stock compensation deductions		1.6			5.1
Other items		(0.7	)		0.6
Change in deferred tax asset valuation allowance		(28.2	)		(40.7	)
Effective income tax rate	—%			—%

Schedule of Deferred Tax Assets

The Company’s deferred tax assets at December 31, 2021 and 2020 consist of the following:


	2021			2020
Net operating loss carryforwards	$	36,590		$	17,885
Research and development tax credits		7,026			3,992
Intangibles		392			360
Stock compensation		6,554			850
Accrued expenses		107			-
Deferred revenue		-			3,606
Other		176			142
Fixed assets		265			56
Lease liability		7,269			7,285
Right of use asset		(7,448	)		(7,181	)
Total deferred tax asset		50,931			26,995
Valuation allowance		(50,931	)		(26,995	)
Net deferred tax assets	$	—		$	—

Leases (Tables)

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Schedule of Leases


Other information	December 31, 2021
Weighted-average remaining operating lease term	9.4 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, 2021.


2022		4,159
2023		4,284
2024		4,412
2025		4,545
2026		4,681
Thereafter		22,389
Total minimum lease payments		44,470
Less: amount of lease payments representing interest		(13,872	)
Present value of future lease payments		30,598
Less: current lease liabilities		(1,747	)
Noncurrent lease liabilities	$	28,851

Schedule of Future Aggregate Minimum Payments


2022	$	4,161
2023		4,284
2024		4,412
2025		4,545
2026		4,681
2027 and beyond		22,388
Total minimum lease payments	$	44,471

Organization - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Subsidiary Sale Of Stock [Line Items]
Accumulated deficit	$ 180,085	$ 95,399

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details

Summary of Significant Accounting Policies - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Summary Of Significant Accounting Policies [Line Items]
Foreign currency exchange (losses) gains	$ 16,000	$ (4,000)
Restricted cash	1,699,000	1,820,000
Fair value of term loan	0
Impairment losses	0	0
Right of use assets	31,350,000	30,551,000
Lease liability	30,598,000
Increase in right-of-use asset	$ 0
Accounting Standards Update 2018-15
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2021
Change in accounting principle, accounting standards update, immaterial effect	false
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
Accounting Standards Update 2019-12
Summary Of Significant Accounting Policies [Line Items]
Change in accounting principle, accounting standards update, adoption date	Jan. 01, 2021
Change in accounting principle, accounting standards update, immaterial effect	false
Lexington Massachusetts facility
Summary Of Significant Accounting Policies [Line Items]
Restricted cash	$ 1,700,000	1,800,000
Woburn Massachusetts Facility
Summary Of Significant Accounting Policies [Line Items]
Restricted cash		$ 100,000

Summary of Significant Accounting Policies - Schedule of Estimated Useful Lives of Assets (Details)	12 Months Ended
	Dec. 31, 2021
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
Leasehold Improvements
Summary Of Significant Accounting Policies [Line Items]
Leasehold improvements, estimated useful lives	Shorter of the estimated usefullife or lease term

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	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Numerator:
Net loss	$ (84,686)	$ (26,511)
Denominator:
Weighted-average shares of common stock outstanding- basic and diluted	34,351,274	32,253,227
Net loss per share-basic and diluted	$ (2.47)	$ (0.82)

- Definition

Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders.

+ References

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+ Details

Summary of Significant Accounting Policies - Computation of Diluted Net Loss per Share Attributable to Common Stockholders (Details) - shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	7,456,337	6,819,891
Unvested Restricted Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	0	3,093
Unvested Restricted Stock Units
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	626,300	0
Outstanding Stock Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	6,830,037	6,816,798

Fair Value Measurements - Schedule of Financial Assets Measured on Recurring Basis (Details) - Recurring Basis - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost	$ 111,040	$ 214,522
Unrealized Loss	(89)
Unrealized Gain		27
Fair Market Value	110,951	214,549
Money Market Funds \| Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost	48,160	214,522
Unrealized Gain		27
Fair Market Value	48,160	$ 214,549
Short-term Marketable Securities \| Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Amortization Cost	51,116
Unrealized Loss	(44)
Fair Market Value	51,072
Long-term Marketable Securities \| Level 2
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

Prepaid Expenses and Other Current Assets - Summary of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Prepaid Expense and Other Assets, Current [Abstract]
Rent and deposits	$ 470
Research and development expenses	858	1,729
Accounts receivable	144	340
Insurance	2,384	2,552
Other	185	102
Total	$ 4,041	$ 4,723

Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Total	$ 9,706	$ 10,499
Accumulated depreciation	(4,184)	(3,212)
Property and equipment, net	5,522	7,287
Lab Equipment
Property Plant And Equipment [Line Items]
Total	6,177	4,166
Furniture and Office Equipment
Property Plant And Equipment [Line Items]
Total	3,238	283
Software
Property Plant And Equipment [Line Items]
Total	291	291
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total	0	1,419
Construction in Progress
Property Plant And Equipment [Line Items]
Total	$ 0	$ 4,340

Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 2,775	$ 1,146

Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Payroll and employee related expenses	$ 4,375	$ 5,062
Professional fees	767	647
Third-party research and development expenses	840	874
Other	119	80
Total	$ 6,101	$ 6,663

Debt - Additional Information (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 11, 2020	Dec. 31, 2021
Debt Instrument [Line Items]
Debt instrument, Interest rate		4.75%
Loan Agreement
Debt Instrument [Line Items]
Interest Expense, Debt		$ 764
Loan Agreement \| Term Loan
Debt Instrument [Line Items]
Principal balance	$ 15,000
Payment terms, description		The Company will make 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 (the “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%
Interest rate floor percentage	0.00%
Debt instrument final payment	$ 150
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%

Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Dec. 10, 2021	Jul. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Class Of Stock [Line Items]
Preferred stock, shares authorized			10,000,000	10,000,000
Preferred Stock, value per share			$ 0.001	$ 0.001
Preferred stock, issued shares			0	0
Preferred stock, outstanding shares			0	0
Common stock, authorized shares			200,000,000	200,000,000
Common stock, par value			$ 0.001	$ 0.001
Common stock, issued shares			34,611,213	33,964,000
Proceeds from issuance of common stock			$ 1,298	$ 1,545
Common stock, outstanding shares			34,611,213	33,964,000
Net proceeds from private placements				$ 40,143
Common Stock
Class Of Stock [Line Items]
Common stock, outstanding shares			34,611,213	33,964,000	30,844,507
Common stock shares issued and sold				2,350,108
Common Stock \| Equity Distribution Agreement
Class Of Stock [Line Items]
Common stock, sale of price per share	$ 0.001
Sales Agent commission	3.00%
Common Stock \| Maximum \| Equity Distribution Agreement
Class Of Stock [Line Items]
Proceeds from issuance of common stock	$ 125,000
Private Placement \| Common Stock
Class Of Stock [Line Items]
Common stock, par value		$ 18.00
Proceeds from issuance of common stock		$ 40,100
Common stock shares issued and sold		2,350,108

Stockholders' Equity - Schedule of Common Stock Shares Reserved for Future Issuance (Details) - shares	Dec. 31, 2021	Dec. 31, 2020
Class Of Stock [Line Items]
Shares of common stock reserved for future issuance	8,382,667	8,292,721
Stock Options Outstanding
Class Of Stock [Line Items]
Shares of common stock reserved for future issuance	6,830,037	6,816,798
Shares Available for Future Grant Under Stock Option Plan
Class Of Stock [Line Items]
Shares of common stock reserved for future issuance	1,552,630	1,475,923

Stock-based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Sep. 17, 2019	Nov. 13, 2014
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares reserved for issuance	8,382,667	8,292,721
Options vesting period	4 years
Weighted-average grant date fair value of stock options granted	$ 22.39	$ 16.41
Total grant date fair value of stock options vested	$ 16,304	$ 7,907
Total unrecognized stock-based compensation expense relating to unvested stock options	$ 39,112	$ 31,006
Unrecognized unvested stock options, weighted-average period	2 years 5 months 26 days	3 years 29 days
Research and Development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 21,750
General and Administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 9,983
Restricted Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total value of restricted stock awards, vested based on estimated fair value of stock	$ 2	$ 20
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting description	vest in equal installments in the first quarter of 2022 and the third quarter of 2022.
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]
Common stock, shares reserved for 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.

Stock-based Compensation - Summary of Stock Option Activity under 2014 Plan and 2019 Plan (Details) - 2014 and 2019 Plan - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Beginning balance	6,816,798	5,968,672
Number of shares, Granted	1,357,426	1,645,859
Number of shares, Exercised	(642,314)	(769,385)
Number of shares, Forfeited	(701,873)	(28,348)
Number of shares, Ending balance	6,830,037	6,816,798	5,968,672
Number of shares, Options exercisable as of December 31, 2021	3,993,231
Number of shares, Options unvested as of December 31, 2021	2,836,806
Weighted average exercise price, Beginning balance	$ 10.11	$ 5.21
Weighted average exercise price, Granted	32.76	24.22
Weighted average exercise price, Exercised	2.02	1.99
Weighted average exercise price, Forfeited	16.48	16.38
Weighted average exercise price, Ending balance	14.72	$ 10.11	$ 5.21
Weighted average exercise price, Options exercisable as of December 31, 2021	9.77
Weighted average exercise price, Options unvested as of December 31, 2021	$ 21.70
Weighted average remaining contractual term (in years), Outstanding	7 years 9 months 3 days	8 years 5 months 12 days	9 years 29 days
Weighted average remaining contractual term (in years), Granted	8 years 25 days	9 years 3 months 18 days
Weighted average remaining contractual term (in years), Options exercisable as of December 31, 2021	7 years 4 months 2 days
Weighted average remaining contractual term (in years), Options unvested as of December 31, 2021	8 years 4 months 9 days
Aggregate intrinsic value, Outstanding	$ 6,987	$ 171,415	$ 73,561
Aggregate intrinsic value, Exercised	11,652	$ 16,667
Aggregate intrinsic value, Options exercisable as of December 31, 2021	6,275
Aggregate intrinsic value, Options unvested as of December 31, 2021	$ 712

Stock-based Compensation - Summary of Grant-date Fair Value of Stock Options Granted on Weighted Average Basis (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Risk-free interest rate	0.50%	1.10%
Expected term (in years)	6 years	6 years
Expected volatility	79.80%	79.10%
Expected dividend yield	0.00%	0.00%

Stock-based Compensation - Summary of Status of Restricted Common Stock (Details)	12 Months Ended
	Dec. 31, 2021 $ / shares shares
Restricted Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Unvested, December 31, 2020 \| shares	3,093
Number of shares, Vested \| shares	(928)
Number of shares, Forfeited \| shares	(2,165)
Number of shares, Unvested, December 31, 2021 \| shares	0
Weighted average fair value, Unvested, December 31, 2020 \| $ / shares	$ 1.75
Weighted average fair value, Vested \| $ / shares	1.75
Weighted average fair value, Forfeited \| $ / shares	1.75
Weighted average fair value, Unvested, December 31, 2021 \| $ / shares	$ 0
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, Unvested, December 31, 2020 \| shares	0
Number of shares, Awarded \| shares	800,000
Number of shares, Forfeited \| shares	(173,700)
Number of shares, Unvested, December 31, 2021 \| shares	626,300
Weighted average fair value, Unvested, December 31, 2020 \| $ / shares	$ 0
Weighted average fair value, Awarded \| $ / shares	9.54
Weighted average fair value, Forfeited \| $ / shares	9.54
Weighted average fair value, Unvested, December 31, 2021 \| $ / shares	$ 9.54

Employee Stock Purchase Plan - Additional Information (Details) - shares		6 Months Ended	12 Months Ended
	Sep. 20, 2019	Jun. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock reserved for future issuance			8,382,667	8,292,721
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			956,021
Period for automatic increase in common available for future issuance	10 years
Percentage of shares issued from outstanding number of shares	1.00%
Shares issued		7,064	31,832

Income Taxes - Additional Information (Details) - USD ($)		12 Months Ended
	Dec. 31, 2014	Dec. 31, 2021	Dec. 31, 2020	Oct. 31, 2019	Mar. 31, 2017	Feb. 28, 2017
Income Taxes Disclosure [Line Items]
Net tax benefit		$ 15,000	$ 35,000
Federal and state deferred tax benefits		0	0
Valuation allowance		50,931,000	26,995,000
Unrecognized tax benefits		0	0
Interest and penalties		$ 0	0
Internal Revenue Service
Income Taxes Disclosure [Line Items]
Period of cumulative change in ownership		3 years
Operating loss carryforwards, utilization after ownership change					$ 10,800,000
Operating loss carryforwards, utilization after five years after ownership change					1,600,000
Operating loss carryforwards, utilization after 15 years thereafter after ownership change					180,000
Remaining pre ownership change in operating loss carryforwards written off due to expiration					$ 1,600,000
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		$ 5,241,000	$ 2,071,000
Federal
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards expire through 2037		$ 22,399,000
Operating loss carryforwards expiration year		2037
Net operating loss carryforwards without expiration		$ 126,672,000
Tax credit carryforwards expiration year		2041
Federal \| Internal Revenue Service
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards				$ 46,123,000		$ 12,400,000
Federal \| Massachusetts
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards		$ 149,071,000
State
Income Taxes Disclosure [Line Items]
Operating loss carryforwards expiration year		2041
State \| Massachusetts
Income Taxes Disclosure [Line Items]
Net operating loss carryforwards		$ 83,467,000
Tax credit carryforwards expiration year		2036

Income Taxes - Schedule of Reconciliation Pre-tax Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Domestic	$ (84,624)	$ (25,744)
Foreign	(47)	(732)
Total	$ (84,671)	$ (26,476)

Income Taxes - Schedule of Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current:
Federal	$ 0	$ 35
State	15	0
Foreign	0	0
Total current	15	35
Deferred:
Federal	0	0
State	0	0
Foreign	0	0
Deferred Income Tax Expense (Benefit)	0	0
Total provision (benefit)	$ 15	$ 35

Income Taxes - Schedule of Reconciliation of U.S. Federal Statutory Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
U.S federal statutory income tax rate	21.00%	21.00%
Permanent differences	0.00%	(0.20%)
State income taxes, net of federal benefit	2.70%	3.00%
Research and development tax credits	3.60%	11.20%
Stock compensation deductions	1.60%	5.10%
Other items	(0.70%)	0.60%
Change in deferred tax asset valuation allowance	(28.20%)	(40.70%)
Effective income tax rate	0.00%

Income Taxes - Schedule of Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Net operating loss carryforwards	$ 36,590	$ 17,885
Research and development tax credits	7,026	3,992
Intangibles	392	360
Stock compensation	6,554	850
Accrued expenses	107
Deferred revenue		3,606
Other	176	142
Fixed assets	265	56
Lease liability	7,269	7,285
Right of use asset	(7,448)	(7,181)
Total deferred tax asset	50,931	26,995
Valuation allowance	(50,931)	(26,995)
Net deferred tax assets	$ 0	$ 0

Research and License Agreements - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended					12 Months Ended
	Dec. 31, 2019	Feb. 28, 2019	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2016	Dec. 31, 2021	Dec. 31, 2020
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 III 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	$ 20	$ 1,000		$ 50
Percentage of shares of common stock issued					5.00%
Percentage of royalty on sublicense revenue			50.00%
Revenue						$ 14,068	$ 36,984
Description of conditions to terminate license agreement						We have the right to terminate for any reason upon 90 days’ prior to written notice. Each party has the right to terminate immediately if the other party ceases to carry on its business. Either party may also terminate the Cambridge License for material breach if such breach remains uncured for 30 days. Cambridge may also terminate the Cambridge License if we fail to diligently develop and commercially exploit at least one Cambridge Licensed Product or we or our affiliates or sub-licenses commence any action against Cambridge to declare or render any claim of the licensed patent rights invalid, unpatentable, unenforceable, or not infringed.
Right to terminate agreement upon prior written notice	90 days	30 days	30 days		3 months
Right to terminate agreement if breach remains uncured	30 days	60 days	30 days		90 days
Right to terminate agreement incase of nonpayment		30 days			30 days
Right to terminate licensed patents upon prior written notice			90 days
Right to terminate agreement upon prior written notice if insolvent		45 days
Annual license fee	$ 50
Dr. Langer
Research And Development Arrangement Contract To Perform For Others [Line Items]
Payment to director						$ 6	1,980
Grant
Research And Development Arrangement Contract To Perform For Others [Line Items]
Decrease in research and development expenses							$ 323
Maximum
Research And Development Arrangement Contract To Perform For Others [Line Items]
Milestone payments	$ 10,500	$ 350	$ 26,000		$ 2,900
Annual license fee per share						$ 7.5
Minimum [Member]
Research And Development Arrangement Contract To Perform For Others [Line Items]
Royalty expense per share						15
Annual license fee per share						$ 5
Patent License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement entered date	2019-12		2018-09		2016-12
Non-Exclusive Patent License Agreement
Research And Development Arrangement Contract To Perform For Others [Line Items]
License agreement entered date		2019-02
Research and Development \| Grant
Research And Development Arrangement Contract To Perform For Others [Line Items]
Amount of funding received as grant				$ 1,596
Grant term period				2 years

Collaboration Agreement - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended					12 Months Ended		24 Months Ended
	Dec. 31, 2019	Jul. 31, 2019	Feb. 28, 2019	Sep. 30, 2018	Dec. 31, 2016	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Right to terminate agreement if breach remains uncured	30 days		60 days	30 days	90 days
Right to terminate agreement incase of nonpayment			30 days		30 days
Research and development						$ 60,923	$ 37,415
License and Collaboration Agreement \| Astellas Pharma LLC
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		$ 80,000
Research and development						$ 885	$ 1,046
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 2b Clinical Trial \| Europe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive		$ 65,000
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 2b Clinical Trial \| Asia
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive		25,000
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 3 Clinical Trial \| Europe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive		100,000
License and Collaboration Agreement \| Astellas Pharma LLC \| Phase 3 Clinical Trial \| Asia
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized potential development milestone payments to receive		40,000
License and Collaboration Agreement \| Maximum \| Astellas Pharma LLC
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

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, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2016
Lessee Lease Description [Line Items]
Lease expense			$ 4,960	$ 835
Hayden LLC \| Lexington Lease
Lessee Lease Description [Line Items]
Lease expiration date		May 31, 2031
Rentable area of office space \| 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
Lessee Lease Description [Line Items]
Payment of fee to landlord			$ 200
Lease Termination Agreement \| ARE-MA Region No. 20, LLC
Lessee Lease Description [Line Items]
Lease expiration date	Mar. 31, 2021
Massachusetts
Lessee Lease Description [Line Items]
Operating lease term					5 years
Lease agreement amended date			2019-11
Lease, description of option to extend			In November 2019, this lease was amended to add additional laboratory and office space as well as extend the termination date for all spaces to February 2025.
Lease, expiration year			2025-02

Leases - Schedule of Leases (Details)	Dec. 31, 2021
Leases [Abstract]
Weighted-average remaining lease term	9 years 4 months 24 days
Weighted-average discount rate	8.50%

Leases - Schedule of Reconciles the Undiscounted Cash Flows to the Operating Lease (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
2022	$ 4,159
2023	4,284
2024	4,412
2025	4,545
2026	4,681
Thereafter	22,389
Total minimum lease payments	44,470
Less: amount of lease payments representing interest	(13,872)
Present value of future lease payments	30,598
Less: current lease liabilities	(1,747)	$ (397)
Noncurrent lease liabilities	$ 28,851	$ 30,597

Leases - Schedule of Future Aggregate Minimum Payments (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Leases [Abstract]
2022	$ 4,161
2023	4,284
2024	4,412
2025	4,545
2026	4,681
2027 and beyond	22,388
Total minimum lease payments	$ 44,471

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Lessee Lease Description [Line Items]
Commitment payments related to research	$ 600
Losses related to indemnification obligations	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	$ 1,700

Employee Benefit Plan - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2019
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	$ 723	$ 400

Related Party Transactions - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Dr. Langer
Related Party Transaction [Line Items]
Payment to director	$ 6	$ 1,980