Document and Entity Information
Document and Entity Information - USD ($) $ in Millions | 12 Months Ended | ||
Dec. 31, 2020 | Mar. 08, 2021 | Jun. 30, 2020 | |
Cover [Abstract] | |||
Document Type | 10-K | ||
Amendment Flag | false | ||
Document Period End Date | Dec. 31, 2020 | ||
Document Fiscal Period Focus | FY | ||
Document Fiscal Year Focus | 2020 | ||
Entity Registrant Name | Homology Medicines, Inc | ||
Entity Central Index Key | 0001661998 | ||
Entity Voluntary Filers | No | ||
Entity Well-known Seasoned Issuer | No | ||
Entity Current Reporting Status | Yes | ||
Trading Symbol | FIXX | ||
Current Fiscal Year End Date | --12-31 | ||
Entity Filer Category | Non-accelerated Filer | ||
Entity Small Business | true | ||
Entity Emerging Growth Company | true | ||
Entity Ex Transition Period | false | ||
ICFR Auditor Attestation Flag | false | ||
Entity Shell Company | false | ||
Entity Common Stock, Shares Outstanding | 50,487,649 | ||
Entity Public Float | $ 511.6 | ||
Entity Interactive Data Current | Yes | ||
Title of 12(b) Security | Common Stock, $0.0001 par value | ||
Security Exchange Name | NASDAQ | ||
Entity File Number | 001-38433 | ||
Entity Incorporation, State or Country Code | DE | ||
Entity Tax Identification Number | 47-3468154 | ||
Entity Address, Address Line One | One Patriots Park | ||
Entity Address, City or Town | Bedford | ||
Entity Address, State or Province | MA | ||
Entity Address, Postal Zip Code | 01730 | ||
City Area Code | 781 | ||
Local Phone Number | 301-7277 | ||
Document Annual Report | true | ||
Document Transition Report | false | ||
Documents Incorporated by Reference | None. |
CONSOLIDATED BALANCE SHEETS
CONSOLIDATED BALANCE SHEETS - USD ($) | Dec. 31, 2020 | Dec. 31, 2019 |
Current assets: | ||
Cash and cash equivalents | $ 217,431,000 | $ 53,774,000 |
Short-term investments | 0 | 208,614,000 |
Prepaid expenses and other current assets | 2,133,000 | 4,189,000 |
Total current assets | 219,564,000 | 266,577,000 |
Property and equipment, net | 37,002,000 | 42,716,000 |
Right-of-use assets | 5,897,000 | |
Restricted cash | 1,274,000 | 1,274,000 |
Total assets | 263,737,000 | 310,567,000 |
Current liabilities: | ||
Accounts payable | 4,722,000 | 2,608,000 |
Accrued expenses and other liabilities | 9,803,000 | 7,644,000 |
Operating lease liabilities | 2,501,000 | |
Deferred rent | 1,313,000 | |
Deferred revenue | 5,632,000 | 809,000 |
Total current liabilities | 22,658,000 | 12,374,000 |
Non-current liabilities: | ||
Operating lease liabilities, net of current portion | 12,941,000 | |
Deferred rent, net of current portion | 9,544,000 | |
Deferred revenue, net of current portion | 32,143,000 | 30,142,000 |
Total liabilities | 67,742,000 | 52,060,000 |
Stockholders’ equity: | ||
Preferred stock, $0.0001 par value, 10,000,000 shares authorized as of December 31, 2020 and 2019, respectively; no shares issued and outstanding at December 31, 2020 and 2019, respectively | ||
Common stock, $0.0001 par value; 200,000,000 shares authorized as of December 31, 2020 and 2019, respectively; 50,268,666 and 45,138,408 shares issued as of December 31, 2020 and 2019, respectively; and 50,265,575 and 45,116,742 shares outstanding as of December 31, 2020 and 2019, respectively | 5,000 | 4,000 |
Additional paid-in capital | 524,358,000 | 457,994,000 |
Accumulated other comprehensive gain | 183,000 | |
Accumulated deficit | (328,368,000) | (199,674,000) |
Total stockholders’ equity | 195,995,000 | 258,507,000 |
Total liabilities and stockholders' equity | $ 263,737,000 | $ 310,567,000 |
CONSOLIDATED BALANCE SHEETS (Pa
CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares | Dec. 31, 2020 | Dec. 31, 2019 |
Statement Of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.0001 | $ 0.0001 |
Preferred stock, shares authorized | 10,000,000 | 10,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value | $ 0.0001 | $ 0.0001 |
Common stock, shares authorized | 200,000,000 | 200,000,000 |
Common stock, shares issued | 50,268,666 | 45,138,408 |
Common stock, shares outstanding | 50,265,575 | 45,116,742 |
CONSOLIDATED STATEMENTS OF OPER
CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Statement Of Income And Comprehensive Income [Abstract] | ||
Collaboration revenue | $ 2,702 | $ 1,666 |
Operating expenses: | ||
Research and development | 100,392 | 89,398 |
General and administrative | 32,573 | 22,211 |
Total operating expenses | 132,965 | 111,609 |
Loss from operations | (130,263) | (109,943) |
Other income: | ||
Interest income | 1,569 | 6,027 |
Total other income | 1,569 | 6,027 |
Net loss | $ (128,694) | $ (103,916) |
Net loss per share-basic and diluted | $ (2.80) | $ (2.47) |
Weighted average common shares outstanding-basic and diluted | 45,910,787 | 42,117,690 |
CONSOLIDATED STATEMENTS OF COMP
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Statement Of Income And Comprehensive Income [Abstract] | ||
Net loss | $ (128,694) | $ (103,916) |
Other comprehensive gain (loss): | ||
Change in unrealized gain (loss) on available for sale securities, net | (183) | 260 |
Total other comprehensive gain (loss) | (183) | 260 |
Comprehensive loss | $ (128,877) | $ (103,656) |
CONSOLIDATED STATEMENTS OF STOC
CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands | Total | ATM | Private Placement | Follow On Offering | Common Stock | Common StockATM | Common StockPrivate Placement | Common StockFollow On Offering | Additional Paid-in Capital | Additional Paid-in CapitalATM | Additional Paid-in CapitalPrivate Placement | Additional Paid-in CapitalFollow On Offering | Accumulated Other Comprehensive Gain (Loss) | Accumulated Deficit |
Beginning balance at Dec. 31, 2018 | $ 196,355 | $ 3 | $ 292,187 | $ (77) | $ (95,758) | |||||||||
Beginning balance, Shares at Dec. 31, 2018 | 37,358,526 | |||||||||||||
Issuance of common stock, net of discounts and issuance costs | $ 22,409 | $ 134,524 | $ 1 | $ 22,409 | $ 134,523 | |||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 1,105,000 | 6,388,889 | ||||||||||||
Issuance of common stock pursuant to employee stock purchase plan | 829 | 829 | ||||||||||||
Issuance of common stock pursuant to employee stock purchase plan, Shares | 55,234 | |||||||||||||
Vesting of common stock from option exercises | 60 | 60 | ||||||||||||
Vesting of common stock from option exercises, Shares | 94,816 | |||||||||||||
Issuance of common stock from option exercises | 351 | 351 | ||||||||||||
Issuance of common stock from option exercises, Shares | 114,277 | |||||||||||||
Stock-based compensation | 7,635 | 7,635 | ||||||||||||
Other comprehensive gain (loss) | 260 | 260 | ||||||||||||
Net loss | (103,916) | (103,916) | ||||||||||||
Ending balance at Dec. 31, 2019 | 258,507 | $ 4 | 457,994 | 183 | (199,674) | |||||||||
Ending balance, Shares at Dec. 31, 2019 | 45,116,742 | |||||||||||||
Issuance of common stock, net of discounts and issuance costs | $ 51,979 | $ 1 | $ 51,978 | |||||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 0 | 5,000,000 | ||||||||||||
Issuance of common stock pursuant to employee stock purchase plan | 938 | 938 | ||||||||||||
Issuance of common stock pursuant to employee stock purchase plan, Shares | 83,848 | |||||||||||||
Vesting of common stock from option exercises | 24 | 24 | ||||||||||||
Vesting of common stock from option exercises, Shares | 18,575 | |||||||||||||
Issuance of common stock from option exercises | $ 176 | 176 | ||||||||||||
Issuance of common stock from option exercises, Shares | 46,410 | 46,410 | ||||||||||||
Stock-based compensation | $ 13,248 | 13,248 | ||||||||||||
Other comprehensive gain (loss) | (183) | $ (183) | ||||||||||||
Net loss | (128,694) | (128,694) | ||||||||||||
Ending balance at Dec. 31, 2020 | $ 195,995 | $ 5 | $ 524,358 | $ (328,368) | ||||||||||
Ending balance, Shares at Dec. 31, 2020 | 50,265,575 |
CONSOLIDATED STATEMENTS OF CASH
CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Cash flows from operating activities: | ||
Net loss | $ (128,694) | $ (103,916) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||
Depreciation | 7,965 | 6,318 |
Noncash lease expense | 939 | |
Stock-based compensation expense | 13,248 | 7,635 |
Accretion of short-term investments | (198) | (1,871) |
Loss on disposal of property and equipment | 888 | 13 |
Changes in operating assets and liabilities: | ||
Prepaid expenses and other current assets | 2,056 | 2,759 |
Accounts payable | 2,459 | (4,452) |
Accrued expenses and other liabilities | 2,432 | 2,315 |
Deferred revenue | 6,824 | (569) |
Deferred rent | 410 | |
Operating lease liabilities | (2,251) | |
Net cash used in operating activities | (94,332) | (91,358) |
Cash flows from investing activities: | ||
Purchases of short-term investments | (19,991) | (286,391) |
Maturities of short-term investments | 228,620 | 256,425 |
Purchases of property and equipment | (3,733) | (21,833) |
Net cash provided by (used in) investing activities | 204,896 | (51,799) |
Cash flows from financing activities: | ||
Proceeds from issuance of common stock in private placement | 51,979 | |
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs | 134,524 | |
Proceeds from issuance of common stock from option exercises | 176 | 351 |
Proceeds from issuance of common stock pursuant to employee stock purchase plan | 938 | 829 |
Net cash provided by financing activities | 53,093 | 158,213 |
Net change in cash, cash equivalents and restricted cash | 163,657 | 15,056 |
Cash, cash equivalents and restricted cash, beginning of period | 55,048 | 39,992 |
Cash, cash equivalents and restricted cash, end of period | 218,705 | 55,048 |
Supplemental disclosures of noncash investing and financing activities: | ||
Reclassification of liability for common stock vested | 24 | 60 |
Property and equipment additions included in accounts payable | 110 | 455 |
Property and equipment additions included in accrued expenses and other liabilities | 249 | |
Unrealized (loss) gain on available for sale securities, net | $ (183) | 260 |
Offering costs included in accrued expenses and other liabilities | 100 | |
ATM | ||
Cash flows from financing activities: | ||
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs | $ 22,509 |
Nature of Business and Basis of
Nature of Business and Basis of Presentation | 12 Months Ended |
Dec. 31, 2020 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
NATURE OF BUSINESS AND BASIS OF PRESENTATION | 1. NATURE OF BUSINESS AND BASIS OF PRESENTATION Nature of Business —Homology Medicines, Inc. (the “Company”) is a clinical-stage genetic medicines company dedicated to translating proprietary gene therapy and gene editing technology into novel treatments for patients with rare genetic diseases with significant unmet medical needs by curing the underlying cause of the disease. The Company was founded in March 2015 as a Delaware corporation. Its principal offices are in Bedford, Massachusetts. Since its inception, the Company has devoted substantially all of its resources to recruiting personnel, developing its technology platform and advancing its pipeline of product candidates, developing and implementing manufacturing processes, building out internal manufacturing and research and development space, and maintaining and building its intellectual property portfolio. The Company is subject to a number of risks similar to those of other companies conducting high-risk, early-stage research and development of product candidates. Principal among these risks are dependency on key individuals and intellectual property, competition from other products and companies, and the technical risks associated with the successful research, development and manufacturing of its product candidates. The Company’s success is dependent upon its ability to continue to raise additional capital in order to fund ongoing research and development, conduct clinical trials, obtain regulatory approval of its products, further expand its manufacturing capacity, successfully commercialize its products, generate revenue, meet its obligations, and, ultimately, attain profitable operations. On April 2, 2018, the Company completed its initial public offering (“IPO”) with the sale of 10,350,000 shares of its common stock, including shares issued upon the exercise in full of the underwriters’ over-allotment option, at a public offering price of $16.00 per share, resulting in net proceeds of $150.8 million, after deducting underwriting discounts and commissions and offering expenses. Upon the closing of the IPO, all of the Company’s outstanding shares of convertible preferred stock automatically converted into 24,168,656 shares of common stock at the applicable conversion ratio then in effect. On April 12, 2019, the Company completed a follow-on public offering of its common stock. The Company sold 5,555,556 shares of its common stock at a public offering price of $22.50 per share and received net proceeds of $116.9 million, after deducting underwriting discounts and commissions and offering expenses. In addition, on April 26, 2019 and May 7, 2019, in connection with the exercise in full of the underwriters’ option to purchase additional shares, the Company issued an aggregate of 833,333 shares of its common stock at a public offering price of $22.50 per share and received net proceeds of $17.6 million, after deducting underwriting discounts and commissions. On March 12, 2020, the Company filed a Registration Statement on Form S-3 (File No. 333-237131) (the “Shelf”) with the Securities and Exchange Commission (“SEC”) in relation to the registration of common stock, preferred stock, debt securities, warrants and/or units of any combination thereof for a period up to three years from the date of the filing. The Shelf became effective on . The Company also simultaneously entered into a sales agreement with Cowen and Company, LLC , as sales agent, providing for the offering, issuance and sale by the Company of up to an aggregate $150.0 million of its common stock from time to time in “at-the-market” offerings under the Shelf (the “ATM”). December 31, 2020 On November 9, 2020, the Company entered into a common stock purchase agreement (the “Stock Purchase Agreement”) with Pfizer Inc. (“Pfizer”), pursuant to which the Company agreed to issue and sell to Pfizer 5,000,000 shares of the Company’s common stock through a private placement transaction (the “Private Placement”) at a purchase price of $12.00 per share, for an aggregate purchase price of $60.0 million (see Note 16). To date, the Company has not generated any revenue from product sales and does not expect to generate any revenue from the sale of product in the foreseeable future. Through December 31, 2020, the Company has financed its operations primarily through public offerings of its common stock, the issuance of convertible preferred stock, and with proceeds from its collaboration and license agreement with Novartis Institutes of BioMedical Research, Inc. (“Novartis”) (see Note 15) and its private placement with Pfizer. During the year ended December 31, 2020, the Company incurred a net loss of $128.7 million and as of December 31, 2020, had $328.4 million in accumulated deficit. The Company expects to incur additional operating losses and negative operating cash flows for the foreseeable future. Based on current projections, management believes that existing cash and cash equivalents will enable the Company to continue its operations into the third quarter of 202 2 . In the absence of a significant source of recurring revenue, the continued viability of the Company beyond that point is dependent on its ability to continue to raise additional capital to finance its operations. There can be no assurance that the Company will be able to obtain sufficient capital to cover its costs on acceptable terms, if at all. Basis of Presentation —The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and have been prepared on a going concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business . |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 12 Months Ended |
Dec. 31, 2020 | |
Accounting Policies [Abstract] | |
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES | 2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Principles of Consolidation —The Company’s consolidated financial statements include the accounts of the Company and its subsidiary, Homology Medicines Securities Corporation, a wholly owned Massachusetts corporation, for the sole purpose of buying, selling, and holding securities on the Company’s behalf. All intercompany balances and transactions have been eliminated in the consolidated financial statements. Use of Estimates —The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, and expenses, and the disclosure of contingent assets and liabilities as of and during the reporting period. The Company bases its estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, revenue recognition, accrued research and development expenses and useful lives assigned to property and equipment. The Company assesses estimates on an ongoing basis; however, actual results could materially differ from those estimates. Comprehensive Income (Loss) — Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company’s only element of other comprehensive income (loss) is unrealized gains and losses on available-for-sale investments. Cash and Cash Equivalents and Restricted Cash —Cash and cash equivalents consist of standard checking accounts, money market accounts and certain investments. The Company considers all highly liquid investments with original or remaining maturities at the time of purchase of 90 days or less to be cash equivalents. Restricted cash consists of cash serving as collateral for letters of credit issued for security deposits for the Company’s facility leases in Bedford, Massachusetts. The following table provides a reconciliation of cash, cash equivalents and restricted cash to amounts shown in the consolidated statements of cash flows: December 31, 2020 2019 (in thousands) Cash and cash equivalents $ 217,431 $ 53,774 Restricted cash 1,274 1,274 Total cash, cash equivalents and restricted cash $ 218,705 $ 55,048 Short-Term Investments —Short-term investments represent holdings of available-for-sale marketable securities in accordance with the Company’s investment policy and cash management strategy. Short-term investments have maturities of greater than 90 days at the time of purchase and mature within one-year from the balance sheet date. 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. Any premium or discount arising at purchase is amortized and/or accreted to interest income and/or expense over the life of the underlying security. Such amortization and accretion, together with interest on securities, are included in interest income in the Company’s consolidated statements of operations. The cost of marketable securities sold is determined based on the specific identification method and any realized gains or losses on the sale of investments are reflected as a component of other income. Concentrations of Credit Risk —Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents and short-term investments. Periodically, the Company may maintain deposits in financial institutions in excess of government insured limits. We believe that we are not exposed to significant credit risk as our deposits are held at financial institutions that management believes to be of high credit quality and the Company has not experienced any losses on these deposits. We regularly invest excess cash with major financial institutions in money market funds, U.S. government and corporate debt securities and commercial paper, all of which can be readily purchased and sold using established markets. As of December 31, 2020 , the Company’s cash and cash equivalents were held with two financial institutions. We believe that the market risk arising from our holdings of these financial instruments is mitigated based on the fact that many of these securities are either government - backed or of high credit rating. Offering Costs —The Company capitalizes incremental legal, professional accounting and other third-party fees that are directly associated with equity financings as other current assets until the transactions are completed. After equity financings are complete, these costs are recorded in stockholders’ equity as a reduction of additional paid-in capital generated as a result of the offering. Leases — In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which eliminated the tests for lease classification under prior U.S. GAAP and requires lessees to recognize right-of-use assets and related lease liabilities on the balance sheet. The FASB subsequently issued the following amendments to ASU 2016-02 that have the same effective date and transition date: ASU No. 2018-01 – Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842 , ASU No. 2018-10 – Codification Improvements to Topic 842 , Leases , ASU No. 2018-11 – Leases (Topic 842): Targeted Improvements , ASU No. 2018-20 – Leases (Topic 842): Narrow-Scope Improvements for Lessors , and ASU No. 2019-01 – Leases (Topic 842): Codification Improvements . The Company adopted these amendments with ASU 2016-02 (collectively, the new leasing standards) effective January 1, 2020. The Company adopted the new leasing standards using the modified retrospective approach, as of January 1, 2020, with no restatement of prior periods or cumulative adjustments to accumulated deficit. The Company elected the package of practical expedients permitted under the transition guidance within the new standard, which, among other things, allows the Company to carry forward the historical lease classification. In addition, the Company elected the practical expedient not to apply the recognition requirements in the leasing standards to short-term leases (a lease that at commencement date has a lease term of 12 months or less and does not contain a purchase option that it is reasonably certain to exercise) and the practical expedient that permits lessees to make an accounting policy election (by class of underlying asset) to not separate lease components of a contract from non-lease components. The Company determines if an arrangement is a lease at contract inception. The Company’s contracts are determined to contain a lease when all of the following criteria based on the specific circumstances of the arrangement are met: (1) there is an identified asset for which there are no substantive substitution rights; (2) the Company has the right to obtain substantially all of the economic benefits from the identified asset; and (3) the Company has the right to direct the use of the identified asset. At the commencement date, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of future lease payments over the expected lease term. The Company’s lease agreements do not provide an implicit rate. As a result, the Company utilizes an estimated incremental borrowing rate to discount lease payments, which is based on the rate of interest the Company would have to pay to borrow a similar amount on a collateralized basis over a similar term. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or lease incentives received. Operating lease cost is recognized over the expected term on a straight-line basis. Variable lease cost is recognized as incurred. The Company acts as sublessor related to a sublease of the Company's former headquarters. Fixed sublease payments received are recognized on a straight-line basis over the sublease term. Right-of-use assets are periodically evaluated for impairment. The expected lease term for those leases commencing prior to January 1, 2020 did not change with the adoption of the new leasing standards. The expected lease term for leases commencing after the adoption of the new leasing standards includes noncancelable lease periods and, when applicable, periods covered by an option to extend the lease if the Company is reasonably certain to exercise that option, as well as periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise that option. As a result of the adoption of the new leasing standards, on January 1, 2020, the Company recorded non-cash transactions to recognize a right-of-use asset of $6.8 million, operating lease liabilities of $17.7 million and the derecognition of deferred rent of $10.9 million originally accounted for under legacy guidance. The adoption did not have a material impact on the condensed consolidated statement of operations. For additional information on the adoption of the new leasing standards, refer to Note 8. January 1, 2020 (in thousands) Prior to adoption of new leasing standards Adjustment for adoption of new leasing standards As Adjusted Right-of-use assets (1)(2) $ — $ 6,835 $ 6,835 Deferred rent (2) $ 1,313 $ (1,313 ) $ — Deferred rent, net of current portion (2) $ 9,544 $ (9,544 ) $ — Operating lease liabilities (3) $ — $ 2,251 $ 2,251 Operating lease liabilities, net of current portion (3) $ — $ 15,441 $ 15,441 (1) Represents capitalization of operating right-of-use assets (2) Represents reclassification of deferred rent and incentives as a reduction to operating right-of-use assets (3) Represents recognition of operating lease liabilities Guarantees and Indemnifications —As permitted under Delaware law, the Company indemnifies its officers, directors, consultants and employees for certain events or occurrences that happen by reason of the relationship with, or position held at, the Company. Through December 31, 2020, the Company had not experienced any losses related to these indemnification obligations, and no claims 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 liabilities have been established. Property and Equipment —Property and equipment are recorded at cost. Expenditures for repairs and maintenance are expensed as incurred. When assets are retired or disposed of, the assets and related accumulated depreciation are derecognized from the accounts, and any resulting gain or loss is included in the determination of net loss. Depreciation is provided using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset. Computer equipment and software 3 years Laboratory equipment and office furniture 5 years Manufacturing equipment 5 - 7 years Leasehold improvements Shorter of the lease term or estimated useful life Impairment of Long-Lived Assets —The Company evaluates its long-lived assets, which consist primarily of property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. To date, no impairments have been recognized for these assets. Research and Development Costs —Research and development costs are charged to expense as incurred. Research and development expense consists of expenses incurred in performing research and development activities, including salaries and benefits, materials and supplies, preclinical and clinical expenses, stock-based compensation expense, depreciation of equipment, contract services, and other outside expenses. Costs for certain development activities are recognized based on an evaluation of the progress to completion of specific tasks using information provided to the Company by its vendors on their actual costs incurred. 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 expense or accrued research and development expense. Income Taxes —The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the Company’s consolidated financial statements and tax returns. Deferred tax assets and liabilities are determined based upon the differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities and for loss and credit carryforwards, using enacted tax rates expected to be in effect in the year in which the differences are expected to reverse. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that these assets may not be realized. The Company determines whether it is more likely than not that a tax position will be sustained upon examination. The tax benefit to be recognized for any tax position that meets the more-likely-than-not recognition threshold is calculated as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement. If it is not more likely than not that a position will be sustained, none of the benefit attributable to the position is recognized. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. Segment Information —Operating segments are identified as components of an enterprise about which separate discrete financial information is made available for evaluation by the chief operating decision maker (“CODM”) in making decisions regarding resource allocation and assessing performance. The CODM is the Company’s Chief Executive Officer. The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is dedicated to translating proprietary gene editing and gene therapy technology into novel treatments for patients with rare genetic diseases. All of the Company’s tangible assets are held in the United States. Revenue Recognition— Revenue is recognized in accordance with FASB Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”). On January 1, 2019, the Company adopted ASC 606 using the full retrospective transition method. Under ASC 606, the Company recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine the appropriate amount of revenue to be recognized for arrangements determined to be within the scope of ASC 606, the Company performs the following five steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect consideration it is entitled to in exchange for the goods or services it transfers to the customer. The promised goods or services in the Company’s arrangements would likely consist of a license, rights to the Company’s intellectual property or research, development and manufacturing services. Performance obligations are promised goods or services in a contract to transfer a distinct good or service to the customer and are considered distinct when (i) the customer can benefit from the good or service on its own or together with other readily available resources and (ii) the promised good or service is separately identifiable from other promises in the contract. In assessing whether promised goods or services are distinct, the Company considers factors such as the stage of development of the underlying intellectual property, the capabilities of the customer to develop the intellectual property on its own or whether the required expertise is readily available and whether the goods or services are integral or dependent to other goods or services in the contract. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration and variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of consideration to which the Company expects to be entitled to. The Company utilizes either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. The Company’s contracts may include development and regulatory milestone payments that are assessed under the most likely amount method and constrained until it is probable that a significant revenue reversal would not occur. Milestone payments that are not within the Company’s control, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At the end of each reporting period, the Company re-evaluates the probability of achievement of such development and regulatory milestones and any related constraint, and if necessary, adjust its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect collaboration revenue in the period of adjustment. For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue 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 (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from the Company’s collaboration arrangement. The Company allocates the transaction price based on the estimated standalone selling price of each performance obligation. The Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the stand-alone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs. Variable consideration is allocated specifically to one or more performance obligations in a contract when the terms of the variable consideration relate to the satisfaction of the performance obligation and the resulting amounts allocated are consistent with the amounts the Company would expect to receive for the satisfaction of each performance obligation. The consideration allocated to each performance obligation is recognized as revenue when control is transferred for the related goods or services. For performance obligations which consist of licenses and other promises, 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. The Company evaluates the measure of progress for its over-time arrangements at each reporting period and, if necessary, updates the measure of progress and revenue recognized. Stock-based Compensation —The Company recognizes compensation expense for awards to employees based on the grant date fair value of stock-based awards on a straight-line basis over the period during which an award holder provides service in exchange for the award. The fair value of options on the date of grant is calculated using the Black-Scholes option pricing model based on key assumptions such as stock price, expected volatility and expected term. The Company’s estimates of these assumptions are primarily based on the trading price of the Company’s stock, historical data, peer company data and judgment regarding future trends and factors. Stock-based awards granted to nonemployees are initially recorded at fair value and are re-measured at each reporting period as the awards vest and expense is recognized over the period the services are provided. The purchase price of common stock under the Company’s employee stock purchase plan (“ESPP”) is equal to 85% of the lesser of (i) the fair market value per share of the common stock on the first business day of an offering period and (ii) the fair market value per share of the common stock on the purchase date. The fair value of the look-back provision under the ESPP is calculated using the Black-Scholes option pricing model. The fair value of the look-back provision plus the 15% discount is recognized as compensation expense over the 180-day purchase period. Fair Value Measurements —Certain assets and liabilities are reported on a recurring basis at fair value. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1—Quoted prices (unadjusted) in active markets for identical assets or liabilities. • Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. Net Loss per Share —Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. The weighted-average number of common shares included in the computation of diluted net loss gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and unvested shares of common stock. Common stock equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is generally the same as basic net loss per share attributable to common stockholders since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Recent Accounting Pronouncements —The Jumpstart Our Business Startups Act of 2012 permits an emerging growth company to take advantage of an extended transition period to comply with new or revised accounting standards applicable to public companies until those standards would otherwise apply to private companies. As an emerging growth company, the Company has elected to take advantage of this extended transition period. In February 2016, the FASB issued new leasing standards to increase transparency and comparability among organization related to their leasing activities. For additional information on the adoption of the new leasing standards, please refer to section titled “Leases” above, and Note 8. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting , In October 2020, the FASB issued ASU 2020-10, Codification Improvements |
Cash and Cash Equivalents
Cash and Cash Equivalents | 12 Months Ended |
Dec. 31, 2020 | |
Cash And Cash Equivalents [Abstract] | |
Cash and Cash Equivalents | 3. CASH AND CASH EQUIVALENTS From time to time, the Company may have cash balances in financial institutions in excess of federal deposit insurance limits. The Company has never experienced any losses related to these balances. The Company considers only those investments that are highly liquid, readily convertible to cash, and that mature within three months from date of purchase to be cash equivalents. The following table summarizes the Company’s cash and cash equivalents: December 31, 2020 2019 (in thousands) Cash $ 250 $ 250 Repurchase agreements — 14,000 Money market funds 217,181 39,524 Total cash and cash equivalents $ 217,431 $ 53,774 |
Short-Term Investments
Short-Term Investments | 12 Months Ended |
Dec. 31, 2020 | |
Investments Disclosure [Abstract] | |
SHORT-TERM INVESTMENTS | 4. SHORT-TERM INVESTMENTS The Company may invest its excess cash in fixed income instruments denominated and payable in U.S. dollars including U.S. treasury securities, commercial paper, corporate debt securities and asset-backed securities in accordance with the Company’s investment policy that primarily seeks to maintain adequate liquidity and preserve capital. The Company has designated all investments as available-for-sale and therefore such investments are reported at fair value and classified as short-term investments on the Company’s consolidated balance sheets . Unrealized gains or losses on investments are recorded in accumulated other comprehensive income or loss, a component of stockholders’ equity, on the Company’s consolidated balance sheets. The Company had no short-term investments as of December 31, 2020. The following table summarizes the Company’s short-term investments as of December 31, 2019: As of December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in thousands) Asset-backed securities $ 14,866 $ 10 $ — $ 14,876 Commercial paper 41,259 — — 41,259 U.S. Treasury securities 59,926 45 — 59,971 Corporate debt securities 92,380 128 — 92,508 Total short-term investments $ 208,431 $ 183 $ — $ 208,614 The Company utilizes the specific identification method in computing realized gains and losses. The Company had no realized gains and losses on its short-term investments for the years ended December 31, 2020 and 2019. The contractual maturity dates of all of the Company’s investments are less than one year. |
Fair Value Measurements
Fair Value Measurements | 12 Months Ended |
Dec. 31, 2020 | |
Fair Value Disclosures [Abstract] | |
FAIR VALUE MEASUREMENTS | 5. FAIR VALUE MEASUREMENTS The Company’s financial instruments consist of cash and cash equivalents, short-term investments, restricted cash and accounts payable. The carrying amount of cash, restricted cash and accounts payable are each considered a reasonable estimate of fair value due to the short-term maturity. Assets measured at fair value on a recurring basis were as follows: Description December 31, 2020 Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Cash equivalents: Money market mutual funds $ 217,181 $ 217,181 $ — $ — Total financial assets $ 217,181 $ 217,181 $ — $ — Description December 31, 2019 Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Cash equivalents: Money market mutual funds $ 39,524 $ 39,524 $ — $ — Repurchase agreements 14,000 — 14,000 — Total cash equivalents $ 53,524 $ 39,524 $ 14,000 $ — Short-term investments: Asset-backed securities $ 14,876 $ — $ 14,876 $ — Commercial paper 41,259 — 41,259 — U.S. Treasury securities 59,971 — 59,971 — Corporate debt securities 92,508 — 92,508 — Total short-term investments $ 208,614 $ — $ 208,614 $ — Total financial assets $ 262,138 $ 39,524 $ 222,614 $ — Short-term securities are valued using models or other valuation methodologies that use Level 2 inputs. These models are primarily industry-standard models that consider various assumptions, including time value, yield curve, volatility factors, default rates, current market and contractual prices for the underlying financial instruments, as well as other relevant economic measures. Substantially all of these assumptions are observable in the marketplace, can be derived from observable data or are supported by observable levels at which transactions are executed in the marketplace. There were no transfers between fair value measure levels during the years ended December 31, 2020 and 2019. |
Property and Equipment
Property and Equipment | 12 Months Ended |
Dec. 31, 2020 | |
Property Plant And Equipment [Abstract] | |
PROPERTY AND EQUIPMENT | 6. PROPERTY AND EQUIPMENT Property and equipment, net consists of the following: December 31, 2020 2019 (in thousands) Laboratory equipment $ 12,703 $ 10,837 Manufacturing equipment 7,754 4,911 Computers and purchased software 1,596 640 Furniture and fixtures 1,363 1,363 Leasehold improvements 29,961 30,862 Assets not yet in service — 2,513 Property and equipment, at cost 53,377 51,126 Less accumulated depreciation and amortization (16,375 ) (8,410 ) Property and equipment, net $ 37,002 $ 42,716 Depreciation expense for the years ended December 31, 2020 and 2019 was approximately $8.0 million and $6.3 million, respectively. The Company disposed of $0.9 million and less than $0.1 million of property and equipment, net during the years ended December 31, 2020 and 2019, respectively. |
Accrued Expenses and Other Liab
Accrued Expenses and Other Liabilities | 12 Months Ended |
Dec. 31, 2020 | |
Payables And Accruals [Abstract] | |
ACCRUED EXPENSES AND OTHER LIABILITIES | 7. ACCRUED EXPENSES AND OTHER LIABILITIES Accrued expenses and other liabilities consist of the following: December 31, 2020 2019 (in thousands) Accrued compensation and benefits $ 6,902 $ 4,551 Accrued research and development expenses 2,393 2,258 Accrued professional fees 291 542 Accrued unvested common stock subject to repurchase 13 37 Accrued other 204 256 Total accrued expenses and other liabilities $ 9,803 $ 7,644 |
Commitments and Contingencies
Commitments and Contingencies | 12 Months Ended |
Dec. 31, 2020 | |
Commitments And Contingencies Disclosure [Abstract] | |
COMMITMENTS AND CONTINGENCIES | 8. COMMITMENTS AND CONTINGENCIES Operating Leases —In September 2016, the Company entered into a noncancelable operating lease beginning in November 2016 for office, laboratory and manufacturing space in Bedford, Massachusetts, that expires in October 2021, with an option for an additional three-year In December 2017, the Company entered into a noncancelable operating lease for approximately 67,000 square feet of research and development, manufacturing and general office space in Bedford, Massachusetts. The lease expires in February 2027 with an option for an additional five-year basis, real estate taxes and operating costs related to the premises. The lease agreement entered into in December 2017 allowed for a tenant improvement allowance not to exceed $ 10.9 million, which the Company received in full, to be applied to the total cost of tenant improvements to the leased premises. The unamortized balance of the tenant improvement allowance was included in deferred rent incentives and has been recorded as a reduction to operating right-of-use asset upon adoption of the new leasing standards. The Company maintains letters of credit, secured by restricted cash, for security deposits totaling $1.3 million as of December 31, 2020 and 2019, respectively, in conjunction with its current leases. The following table summarizes operating lease costs and variable lease costs, as well as sublease income for the year ended December 31, 2020: Year ended December 31, 2020 Amount (in thousands) Operating lease costs $ 2,492 Variable lease costs 2,355 Sublease income (913 ) Net lease cost $ 3,934 Rent expense for the year ended December 31, 2019 was $1.4 million. The maturities of our operating lease liabilities as of December 31, 2020 were as follows: Amount For the Years Ending December 31, (in thousands) 2021 $ 3,834 2022 2,987 2023 3,077 2024 3,169 Thereafter 7,197 Total undiscounted lease payments $ 20,264 Less: imputed interest (4,822 ) Present value of operating lease liabilities $ 15,442 The following table summarizes the lease term and discount rate as of December 31, 2020: As of December 31, 2020 Weighted-average remaining lease term (years) Operating leases 5.9 Weighted-average discount rate Operating leases 9.9 % The following table summarizes the supplemental cash flow information related to the Company's operating leases for the year ended December 31, 2020. Year ended December 31, 2020 (in thousands) Cash paid for amounts included in the measurement of lease liabilities $ 3,804 |
License Agreements
License Agreements | 12 Months Ended |
Dec. 31, 2020 | |
License Agreement [Abstract] | |
LICENSE AGREEMENTS | 9. LICENSE AGREEMENTS City of Hope In April 2016, the Company entered into a license agreement with City of Hope (“COH”), an academic research and medical center. The license term extends until the last to expire patent, unless terminated earlier by either party under certain provisions. The Company is required to pay an annual license fee of $25,000, reimburse COH for patent costs incurred, pay amounts up to $3.2 million upon the achievement of certain development and commercialization milestones for each product under the license, pay royalties on future sales in the low single-digits and royalties on sublicense revenue in the low double-digits, if any. During the year ended December 31, 2019, the Company paid $50,000 to COH upon dosing the first patient in the pheNIX Phase 1/2 clinical trial. During the year ended December 31, 2020, the Company paid $75,000 plus interest to COH in connection with achievement of a milestone event. As a result of the execution of the Collaboration Agreement with Novartis (see Note 15), the Company paid $4.5 million to COH in December 2017, under the terms of the license agreement. In May 2015, the Company entered into a sponsored research agreement with COH with a goal to identify potential treatments for diseases in humans. Under this agreement, the Company recorded $0.1 million in research and development expense for the year ended December 31, 2019. The agreement terminated in September 2019 in accordance with its terms. California Institute of Technology In September 2016, the Company entered into a co-exclusive license agreement with the California Institute of Technology (“Caltech”), an academic research institute. The license term extends until the expiration, revocation, invalidation or unenforceability of the licensed patent rights. The Company is required to pay an annual minimal royalty fee of $20,000, reimburse for patent costs incurred, pay an amount up to $7.2 million upon the achievement of certain development and regulatory milestones and pay royalties on future sales in the low single-digits and royalties on sublicense revenue in the mid to high single-digits, if any. |
Income Taxes
Income Taxes | 12 Months Ended |
Dec. 31, 2020 | |
Income Tax Disclosure [Abstract] | |
INCOME TAXES | 10. INCOME TAXES A reconciliation between the U.S. federal statutory tax rate and the Company’s effective tax rate is summarized as follows: For the Years Ended December 31, 2020 2019 Federal statutory rate 21.0 % 21.0 % Tax credits 10.6 % 13.4 % State taxes, net of federal tax benefit 8.0 % 6.1 % Non-deductible expenses (1.8 %) (1.0 %) Change in valuation allowance (37.8 %) (39.5 %) Effective income tax rate — % — % The principal components of the Company’s deferred tax assets and liabilities consist of the following: December 31, 2020 2019 (in thousands) Deferred tax assets: Net operating losses $ 72,838 $ 41,589 R&D credits 39,888 25,328 Deferred revenue 8,251 8,456 Deferred rent 4,219 2,966 Capitalized R&D costs 1,039 1,207 Equity compensation 1,368 883 Accrued expense and other 1,914 108 Total deferred tax assets 129,517 80,537 Deferred tax liabilities: Depreciation (3,726 ) (2,744 ) Other (757 ) — Total deferred tax liabilities (4,483 ) (2,744 ) Valuation allowance (125,034 ) (77,793 ) Net deferred taxes $ — $ — The Company has no income tax expense due to the operating loss incurred for the years ended December 31, 2020 and 2019. The Company has provided a valuation allowance for the full amount of the net deferred tax assets as the realization of the net deferred tax assets is not determined to be more likely than not. At December 31, 2020, the Company had $265.1 million and $271.5 million of federal and state net operating loss carryforwards, respectively, that expire at various dates through 2040. Included in the federal net operating loss carryforwards of $265.1 million is $233.6 million that can be carried forward indefinitely. At December 31, 2020, the Company had $34.2 million and $7.2 million of federal and state research and development credit carryforwards, respectively, that expire at various dates through 2040. Included in the $34.2 million of federal research and development credit carryforwards is $29.0 million of orphan drug credit carryforwards. The valuation allowance increased in 2020 and 2019 by $47.2 million and $40.2 million, respectively, due to the increase in the deferred tax assets by the same amounts, primarily due to the net operating loss carryforwards and research and development tax credits not utilized. For all years through December 31, 2020, the Company generated research credits but has not conducted a study to document the qualified activities. This study may result in an adjustment to the Company’s research and development credit carryforwards. Since a full valuation allowance has been provided against the Company’s research and development credits, any reduction in the gross deferred tax asset established for the research and development credit carryforwards would not result in any net impact to the Company’s consolidated financial statements. Realization of the future tax benefits is dependent on many factors, including the Company’s ability to generate taxable income within the net operating loss carryforward period. Under the provisions of the Internal Revenue Code, certain substantial changes in the Company’s ownership, including a sale of the Company or significant changes in ownership due to sales of equity, may have limited, or may limit in the future, the amount of net operating loss carryforwards that could be used annually to offset future taxable income. The Company has not completed a study to assess whether a change of control has occurred or whether there have been multiple changes of control since the Company’s formation due to the significant complexity and cost associated with such study and because there could be additional changes in control in the future. As a result, the Company is not able to estimate the effect a change in control would have, if any, on the Company’s ability to utilize its net operating loss and research and development credit carryforwards in the future. The Company files tax returns in the United States and Massachusetts. All tax years since inception remain open to examination by the major taxing jurisdictions to which the Company is subject, as carryforward attributes generated in years past may still be adjusted upon examination by the Internal Revenue Service (“IRS”) or other authorities if they have or will be used in a future period. The Company is not currently under examination by the IRS or any other jurisdictions for any tax years. As of December 31, 2020 , the Company had no uncertain tax positions. 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, 2020 and 2019 . |
Stockholder's Equity
Stockholder's Equity | 12 Months Ended |
Dec. 31, 2020 | |
Equity [Abstract] | |
STOCKHOLDERS' EQUITY | 11. STOCKHOLDERS’ EQUITY Common Stock —Voting, dividend and liquidation rights of the holders of the common stock are subject to and qualified by the rights, powers and preferences of the holders of the preferred stock. Voting —Each holder of outstanding shares of common stock are entitled to one vote in respect of each share. The holders of outstanding shares of common stock, voting together as a single class, shall be entitled to elect one director. The number of authorized shares of common stock may be increased or decreased by the affirmative vote of a majority of the outstanding shares of common stock and preferred stock voting together as a single class. Dividends —Subject to the payment in full of any preferential dividends to which the holders of preferred stock are entitled, the holders of common stock shall be entitled to receive dividends out of funds legally available therefore at such times and in such amounts as the Board of Directors may determine in its sole discretion. Liquidation Rights —In the event of any voluntary or involuntary liquidation, dissolution or winding-up of the Company, after the payment or provision for payment of all debts and liabilities of the Company and any preferential amounts to which the holders of preferred stock are entitled with respect to the distribution of assets in liquidation, the holders of common stock shall be entitled to share ratably in the remaining assets of the Company available for distribution. There were 50,265,575 and 45,116,742 shares of common stock outstanding at December 31, 2020 and 2019, respectively. Preferred Stock —As of December 31, 2020 and 2019, there were no shares of preferred stock issued and outstanding. |
Stock Incentive Plans
Stock Incentive Plans | 12 Months Ended |
Dec. 31, 2020 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
STOCK INCENTIVE PLANS | 12. STOCK INCENTIVE PLANS 2015 Stock Incentive Plan In December 2015, the Company’s Board of Directors adopted the 2015 Stock Incentive Plan (the “2015 Plan”), which provided for the grant of qualified incentive and nonqualified stock options or restricted stock awards to the Company’s employees, officers, directors, advisors, and outside consultants. Stock options generally vest over a four-year 2018 Incentive Award Plan In March 2018, the Company’s Board of Directors adopted and the Company’s stockholders approved the Homology Medicines, Inc. 2018 Incentive Award Plan (the “2018 Plan” and, together with the 2015 Plan, the “Plans”), which became effective on the day prior to the first public trading date of the Company’s common stock. Upon effectiveness of the 2018 Plan, the Company ceased granting new awards under the 2015 Plan. The 2018 Plan provides for the grant of incentive stock options, nonqualified stock options, restricted stock awards, restricted stock units, stock appreciation rights and other stock or cash-based awards to employees and consultants of the Company and certain affiliates and directors of the Company. The number of shares of common stock initially available for issuance under the 2018 Plan was 3,186,205 shares of common stock plus the number of shares subject to awards outstanding under the 2015 Plan that expire, terminate or are otherwise surrendered, cancelled, forfeited or repurchased by the Company on or after the effective date of the 2018 Plan. In addition, the number of shares of common stock available for issuance under the 2018 Plan is subject to an annual increase on the first day of each calendar year beginning on January 1, 2019 and ending on and including January 1, 2028 equal to the lesser of (i) 4% of the Company’s outstanding shares of common stock on the final day of the immediately preceding calendar year and (ii) such smaller number of shares of common stock as determined by the Company’s Board of Directors, provided that not more than 20,887,347 shares of common stock may be issued under the 2018 Plan upon the exercise of incentive stock options (the “Evergreen Provision”). As of December 31, 2020, there were 2,397,547 shares available for future grant under the 2018 Plan. On January 1, 2021, pursuant to the Evergreen Provision, an additional 2,010,623 shares were added to the 2018 Plan, representing 4% of total common shares outstanding at December 31, 2020. 2018 Employee Stock Purchase Plan In March 2018, the Company’s Board of Directors adopted, and the Company’s stockholders approved, the Homology Medicines, Inc. 2018 Employee Stock Purchase Plan (the “2018 ESPP”). The 2018 ESPP allows employees to buy Company stock through after-tax payroll deductions at a discount from market value. The 2018 ESPP is intended to qualify as an “employee stock purchase plan” under Section 423 of the Internal Revenue Code. The number of shares of common stock initially available for issuance under the 2018 ESPP was 353,980 shares of common stock plus an annual increase on the first day of each calendar year beginning on January 1, 2019 and ending on and including January 1, 2028 equal to the lesser of (i) 1% of the Company’s outstanding shares of common stock on the final day of the immediately preceding calendar year and (ii) such smaller number of shares of common stock as determined by the Company’s Board of Directors, provided that not more than 4,778,738 shares of common stock may be issued under the 2018 ESPP (the “ESPP Evergreen Provision”). At December 31, 2020, there were 1,039,650 shares available for future issuance under the 2018 ESPP. On January 1, 2021, pursuant to the ESPP Evergreen Provision, an additional 502,655 shares were added to the 2018 ESPP, representing 1% of total common shares outstanding at December 31, 2020. Under the 2018 ESPP, employees may purchase common stock through after-tax payroll deductions at a price equal to 85% of the lower of the fair market value on the first trading day of an offering period or the last trading day of an offering period. The 2018 ESPP generally provides for offering periods of six months in duration that end on the final trading day of each February and August. In accordance with the Internal Revenue Code, no employee will be permitted to accrue the right to purchase stock under the 2018 ESPP at a rate in excess of $25,000 worth of shares during any calendar year during which such a purchase right is outstanding (based on the fair market value per share of the Company’s common stock as of the first day of the offering period). During the year ended December 31, 2020, 83,848 shares were issued under the 2018 ESPP for aggregate proceeds to the Company of $0.9 million. During the year ended December 31, 2019, 55,234 shares were issued under the 2018 ESPP for aggregate proceeds to the Company of $0.8 million. Pursuant to the 2018 ESPP, the Company recorded stock-based compensation of $0.2 million and $0.2 million for the years ended December 31, 2020 and 2019, respectively. Stock-based compensation expense The Company recognizes compensation expense for awards to employees based on the grant date fair value of stock-based awards on a straight-line basis over the period during which an award holder provides service in exchange for the award, which is generally the vesting period. The fair value of each option award is estimated on the date of grant using the Black-Scholes option-pricing model, with the assumptions noted in the table below. Expected volatility for the Company’s common stock was determined based on an average of the historical volatility of a peer group of publicly traded companies that are similar to the Company. The expected term of options granted to employees was calculated using the simplified method, which represents the average of the contractual term of the option and the weighted-average vesting period of the option. The Company uses the simplified method because it does not have sufficient historical option exercise data to provide a reasonable basis upon which to estimate expected term. The contractual life of the options was used for the expected term of options granted to non-employees. The assumed dividend yield is based upon the Company’s expectation of not paying dividends in the foreseeable future. The risk-free rate is based on the U.S. Treasury yield curve in effect at the time of grant for periods commensurate with the expected term of the award. The Company recognizes forfeitures as they occur. The assumptions used in the Black-Scholes option pricing model are as follows: For the Years Ended December 31, 2020 2019 Expected volatility 63.2% — 66.3% 62.4% — 64.7% Weighted-average risk-free interest rate 0.31% — 1.73% 1.36% — 2.60% Expected dividend yield — % — % Expected term (in years) 5.5 - 6.25 6.25 Underlying common stock fair value $9.82 - $21.75 $12.73 — $30.34 The Company recorded stock-based compensation expense related to stock options and shares purchased under the 2018 ESPP as follows: For the Years Ended December 31, 2020 2019 (in thousands) Research and development $ 6,390 $ 4,164 General and administrative 6,858 3,471 $ 13,248 $ 7,635 As of December 31, 2020, there was $29.2 million of unrecognized compensation expense related to unvested employee and non-employee share-based compensation arrangements granted under the Plans. The unrecognized compensation expense is estimated to be recognized over a period of 2.4 years at December 31, 2020. A summary of option activity under the Plans during the year ended December 31, 2020 is as follows: Number of Options Weighted- Average Exercise Price per Share Weighted- Average Remaining Contractual Term (in Years) Aggregate Intrinsic Value (in thousands) Outstanding at January 1, 2020 4,843,018 $ 14.78 8.5 $ 33,809 Granted 1,311,200 $ 17.82 Exercised (46,410 ) $ 3.79 Cancelled/Forfeited (266,984 ) $ 22.75 Outstanding at December 31, 2020 5,840,824 $ 15.18 7.8 $ 12,278 Vested and expected to vest at December 31, 2020 5,840,824 $ 15.18 7.8 $ 12,278 Exercisable at December 31, 2020 2,869,589 $ 12.18 7.0 $ 10,803 The total intrinsic value of options exercised during the year ended December 31, 2020 and 2019 was $0.6 million and $1.9 million, respectively. The weighted-average grant date fair value of options granted during the years ended December 31, 2020 and 2019 was $10.39 and $12.90, respectively. Stock options granted pursuant to the 2015 Plan permit option holders to elect to exercise unvested options in exchange for unvested common stock. Options granted under the 2015 Plan that are exercised prior to vesting will continue to vest according to the respective option agreement, and such unvested shares are subject to repurchase by the Company at the optionee’s original exercise price in the event the optionee’s service with the Company voluntarily or involuntarily terminates. A summary of the Company’s unvested common stock from early exercises that is subject to repurchase by the Company is as follows: Shares Unvested shares—January 1, 2020 21,666 Vested (18,575 ) Issued — Repurchased — Unvested shares—December 31, 2020 3,091 As of December 31, 2020 and 2019, 3,091 shares and 21,666 shares, respectively, remained subject to a repurchase right by the Company, with a related liability included in accrued expenses and other liabilities in the consolidated balance sheets of less than $0.1 million as of each date. |
Net Loss Per Share
Net Loss Per Share | 12 Months Ended |
Dec. 31, 2020 | |
Earnings Per Share [Abstract] | |
NET LOSS PER SHARE | 13. NET LOSS PER SHARE The Company’s potential dilutive securities, which include unvested common stock from the early-exercise of stock options and outstanding common stock options, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at December 31, 2020 and 2019 , from the computation of diluted net loss per share attributable to common stockholders because including them would have had an anti-dilutive effect: As of December 31, 2020 2019 Unvested common stock from early exercise of options 3,091 21,666 Stock options to purchase common stock 5,840,824 4,843,018 Total 5,843,915 4,864,684 |
Defined Contribution Plan
Defined Contribution Plan | 12 Months Ended |
Dec. 31, 2020 | |
Compensation And Retirement Disclosure [Abstract] | |
DEFINED CONTRIBUTION PLAN | 14. DEFINED CONTRIBUTION PLAN The Company has a 401(k) defined contribution plan (the “401(k) Plan”) for all of its employees. Eligible employees may make pretax contributions to the 401(k) Plan up to statutory limits, while the Company contributes to the plan at the discretion of the Board of Directors. The Company’s discretionary match made under the 401(k) Plan for the years ended December 31, 2020 and 2019 was $0.7 million and $0.5 million, respectively. |
Collaboration and License Agree
Collaboration and License Agreement | 12 Months Ended |
Dec. 31, 2020 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
COLLABORATION AND LICENSE AGREEMENT | 15. COLLABORATION AND LICENSE AGREEMENT Summary of Agreement In November 2017, the Company entered into a collaboration and license agreement with Novartis (as amended, the “Collaboration Agreement”) for the research, development, manufacturing and commercialization of products using the Company’s gene-editing technology for the treatment of certain ophthalmic targets and sickle cell disease. In February 2019, Novartis elected to discontinue the sickle cell disease program under the Collaboration Agreement effective in August 2019. In May 2020, Novartis confirmed an ophthalmic target for a therapeutic editing program. Additionally, in accordance with the terms of the Collaboration Agreement, Novartis’ right to substitute other ophthalmic targets expired. For additional information on the Collaboration Agreement, please refer to Note 17. Under the terms of the Collaboration Agreement, the Company granted Novartis a research license, a development and commercialization license, and a manufacturing license, under certain of its intellectual property rights to research, develop, manufacture and commercialize ophthalmic targets. Upon entering into the Collaboration Agreement in November 2017, the Company received an upfront, nonrefundable payment of $35.0 million and issued additional shares of its Series B preferred stock to Novartis for consideration of $10.0 million, in addition to the $5.0 million of Series B preferred stock Novartis had purchased in July 2017. The Company recorded the November 2017 issuance of Series B preferred stock at its estimated fair value of $11.7 million, including $1.7 million of the upfront payment, and allocated the remaining $33.3 million of the upfront payment to the Collaboration Agreement. The Collaboration Agreement consists of a research term, where the Company and Novartis were collaborating to perform research and conduct preclinical development to identify candidates that modulate ophthalmic targets. The Collaboration Agreement also includes exploratory work on the applicability of the gene editing technology with respect to other gene targets. The Company’s obligation to perform such exploratory research was extended pursuant an amendment to the Collaboration Agreement was set to conclude in May 2021. The Company was responsible for the manufacturing of proprietary research grade human hematopoietic stem cell derived adeno-associated virus vectors (“AAVHSCs”) during the research term. Novartis agreed to reimburse research activities performed by the Company at a full-time equivalent rate (“FTE”) and manufacturing activities at cost, up to a maximum of $17.0 million during the research term, as specified and defined in the Collaboration Agreement. Novartis agreed to pay the Company a target fee of $5.0 million if the target meets certain success criteria during the research term (the “target fee trigger date”). The research term was to continue for five years from the effective date of the Collaboration Agreement. Pursuant to the Collaboration Agreement, the Company also agreed to participate on a joint steering committee and a joint manufacturing subcommittee, with equal representation from both the Company and Novartis. Novartis had the exclusive right to develop and commercialize one ophthalmic candidate or product arising from the research activities. Subject to certain limitations pursuant to the terms of the Collaboration Agreement, Novartis agreed to fund all development and commercialization costs. The Company was responsible for manufacturing candidates and products for Novartis during the development and commercialization terms. The Company’s manufacturing activities were to be reimbursed at cost during the development term and at cost plus a margin during the commercialization term, as defined in the Collaboration Agreement. If the Company was not able to manufacture candidates or products that met the quality or quantity requirements of Novartis, then Novartis would have had the right to designate a third-party contract manufacturer or manufacture such candidates or products itself. In accordance with the Collaboration Agreement, taking into consideration Novartis’ election to discontinue the sickle cell disease program, and the expiration of Novartis’ rights to make substitutions of an ophthalmic target, the Company was also eligible to receive up to a total of $265.0 million in milestone payments, including up to $90.0 million in development milestone payments, up to $85.0 million in regulatory milestone payments and up to $90.0 million in commercial milestone payments, with respect to the licensed products. The Company was also eligible to earn tiered royalties on net sales of licensed products by Novartis, its affiliates or sublicensees, ranging from mid-single-digit, to sub-teen double-digit percentages, and such royalties were potentially subject to various reductions and offsets. If any of the exploratory research efforts were advanced into formal research and development programs, the parties agreed to negotiate the economics including potential milestone payments for such programs at that time. Revenue Recognition The Company determined that the (1) research, development and commercialization and manufacturing licenses, (2) the research activities performed by the Company (3) service on the joint committees and (4) manufacturing during the research and development terms represented a single performance obligation under the Collaboration Agreement. Since the option for Novartis to obtain manufacturing during the commercialization term from the Company is at a price that would reflect the standalone selling price, the option does not provide Novartis with a material right and is therefore not a performance obligation under the contract. The Company has concluded that the research, development and commercialization and manufacturing licenses are not distinct from the research activities and manufacturing during the research and development term as Novartis cannot benefit from the licenses without the Company performing the research and manufacturing services. These services are so specialized and rely on the Company’s expertise in gene editing technologies not available in the marketplace. As a result, these licenses have been combined with the research activities, service on the joint committees and the manufacturing during the research and development terms as a single performance obligation. The transaction price consists of the $33.3 million non-refundable upfront payment, net of amounts classified as equity, and projected reimbursable research and manufacturing activities, which have been estimated using the expected value method. None of the target fees or development and regulatory milestone payments have been included in the transaction price, as all are fully constrained. As part of the evaluation of the constraint, the Company considered numerous factors, including the fact that achievement of the milestones is outside of the Company’s control and is contingent upon the success of the Company’s preclinical studies, clinical trials, Novartis’ efforts and the receipt of regulatory approval. In addition, the Company has determined that the commercial milestones and sales-based royalties will be recognized when the related sales occur as they were determined to relate predominately to the licenses transferred to Novartis, and therefore have also been excluded from the transaction price. The Company will re-evaluate the transaction price, including estimated variable consideration included in the transaction price and all constrained amounts, in each reporting period and as uncertain events are resolved or other changes in circumstances occur. The Company identified only one performance obligation in the Collaboration Agreement. Therefore, the Company allocated the transaction price at the onset of the contract to the single performance obligation. The Company recognizes revenue over time using a cost-to-cost method, which it believes best depicts the transfer of control to the customer. Under the cost-to-cost method, the extent of progress towards completion is measured based on the ratio of actual costs incurred to the total estimated costs expected upon satisfying the identified performance obligation. Under this method, revenue is recorded over the performance period as a percentage of the estimated transaction price based on the extent of progress towards completion. As of December 31, 2020, the aggregate amount of the transaction price related to the unsatisfied portion of the performance obligation is $30.2 million, and the Company will recognize this revenue as the research and manufacturing activities are performed, which was expected to occur over a period of time that was estimated to conclude in 2027. In estimating the total costs to satisfy its single performance obligation pursuant to the Novartis agreement, the Company is required to make significant estimates including the expected time it will take to fulfill the performance obligation, which, as of December 31, 2020, was expected to be approximately ten years from the date the Collaboration Agreement was entered into, and the expected costs associated with manufacturing during the research and development terms for a novel manufacturing process as well as the probability of success of a target to move into the development phase. The Company has made estimates of such costs utilizing its experience with similar product candidates, however not identical to those in the Collaboration Agreement. In making such estimates, significant judgment is required to evaluate those key assumptions related to cost estimates. The cumulative effect of revisions to the total estimated costs to complete the Company’s single performance obligation will be recorded in the period in which the changes are identified and amounts can be reasonably estimated. While such revisions will have no impact on the Company’s reported cash flows, a significant change in these assumptions and estimates could have a material impact on the timing and amount of revenue recognized in future periods. During the years ended December 31, 2020 and 2019, the Company recognized revenue under the Collaboration Agreement of $2.3 million and $1.7 million, respectively, of which $0.8 million and $0.6 million was included in deferred revenue at the beginning of each such period. As of December 31, 2020 and 2019, there was approximately $30.2 million and $31.0 million of deferred revenue related to the Collaboration Agreement, respectively. In addition, as of December 31, 2020 and 2019, the Company has recorded accounts receivable of $0.4 million, related to reimbursable research and development costs under the Collaboration Agreement, which are included in prepaid expenses and other current assets on the consolidated balance sheets. |
Pfizer Stock Purchase Agreement
Pfizer Stock Purchase Agreement | 12 Months Ended |
Dec. 31, 2020 | |
Pfizer Inc. | |
PFIZER STOCK PURCHASE AGREEMENT | 16. PFIZER STOCK PURCHASE AGREEMENT On November 9, 2020, the Company entered into a common stock purchase agreement (the “Stock Purchase Agreement”) with Pfizer Inc. (“Pfizer”), pursuant to which the Company agreed to issue and sell to Pfizer 5,000,000 shares of the Company’s common stock through a private placement transaction (the “Private Placement”) at a purchase price of $12.00 per share, for an aggregate purchase price of $60.0 million. The shares of common stock sold to Pfizer are subject to a one-year lock-up from closing, during which time Pfizer is prohibited from selling or otherwise disposing of such shares. Under the Stock Purchase Agreement, Pfizer was granted an exclusive right of first refusal (the “ROFR”) for a 30-month period (the “ROFR Period”) beginning on the date of the closing of the Private Placement (collectively, the “ROFR Provision”), to negotiate a potential collaboration on the development and commercialization of HMI-102 and HMI-103. HMI-102 and HMI-103 The Company recorded the issuance of common stock at its estimated fair value of $52.0 million, which reflects a discount for the lack of marketability of the shares. The remaining $8.0 million of aggregate purchase price was allocated to the other elements of the Stock Purchase Agreement, which represent a contract with a customer. The Company concluded that the Information Committee represents the only performance obligation under the contract. The ROFR does not provide Pfizer with a material right and is therefore not a performance obligation. As such, the Company allocated the $8.0 million to the Information Committee obligation. The Company will recognize revenue over time as the measure of progress which it believes best depicts the transfer of control to Pfizer. The Information Committee will meet regularly over the ROFR Period to share information which results in recognition of the transaction price over the 30-month ROFR Period. During the year ended December 31, 2020, the Company recognized collaboration of $0.4 million, and as of December 31, 2020, there was approximately $7.6 million of deferred revenue related to the Company’s obligation to Pfizer. |
Subsequent Event
Subsequent Event | 12 Months Ended |
Dec. 31, 2020 | |
Subsequent Events [Abstract] | |
SUBSEQUENT EVENT | 17. SUBSEQUENT EVENT On February 26, 2021, Homology received notice from Novartis that they had elected to terminate the Collaboration Agreement with the Company, with respect to the remaining ophthalmic target under the Collaboration Agreement. Accordingly, the notice served as notice of Novartis’ termination of the Collaboration Agreement in its entirety, which will be effective on August 26, 2021. As a result of the termination of the Collaboration Agreement, Homology regained worldwide exclusive rights from Novartis to research, develop, manufacture and commercialize Homology’s proprietary nuclease-free gene editing technology platform for an ophthalmic target (see Note 15). Homology announced its plans to continue to advance the program toward naming a development candidate. The Company and Novartis believe that results of studies conducted under the C ollaboration Agreement provide early proof-of-principle and support a nuclease-independent approach to editing of relevant cell types in the eye after sub-retinal injection, and are the subject of a planned presentation at an upcoming scientific meeting . |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 12 Months Ended |
Dec. 31, 2020 | |
Accounting Policies [Abstract] | |
Basis of Presentation | Basis of Presentation —The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and have been prepared on a going concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business . |
Principles of Consolidation | Principles of Consolidation —The Company’s consolidated financial statements include the accounts of the Company and its subsidiary, Homology Medicines Securities Corporation, a wholly owned Massachusetts corporation, for the sole purpose of buying, selling, and holding securities on the Company’s behalf. All intercompany balances and transactions have been eliminated in the consolidated financial statements. |
Use of Estimates | Use of Estimates —The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenue, and expenses, and the disclosure of contingent assets and liabilities as of and during the reporting period. The Company bases its estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, revenue recognition, accrued research and development expenses and useful lives assigned to property and equipment. The Company assesses estimates on an ongoing basis; however, actual results could materially differ from those estimates. |
Comprehensive Income (Loss) | Comprehensive Income (Loss) — Comprehensive income (loss) is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources. The Company’s only element of other comprehensive income (loss) is unrealized gains and losses on available-for-sale investments. |
Cash and Cash Equivalents and Restricted Cash | Cash and Cash Equivalents and Restricted Cash —Cash and cash equivalents consist of standard checking accounts, money market accounts and certain investments. The Company considers all highly liquid investments with original or remaining maturities at the time of purchase of 90 days or less to be cash equivalents. Restricted cash consists of cash serving as collateral for letters of credit issued for security deposits for the Company’s facility leases in Bedford, Massachusetts. The following table provides a reconciliation of cash, cash equivalents and restricted cash to amounts shown in the consolidated statements of cash flows: December 31, 2020 2019 (in thousands) Cash and cash equivalents $ 217,431 $ 53,774 Restricted cash 1,274 1,274 Total cash, cash equivalents and restricted cash $ 218,705 $ 55,048 |
Short-Term Investments | Short-Term Investments —Short-term investments represent holdings of available-for-sale marketable securities in accordance with the Company’s investment policy and cash management strategy. Short-term investments have maturities of greater than 90 days at the time of purchase and mature within one-year from the balance sheet date. 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. Any premium or discount arising at purchase is amortized and/or accreted to interest income and/or expense over the life of the underlying security. Such amortization and accretion, together with interest on securities, are included in interest income in the Company’s consolidated statements of operations. The cost of marketable securities sold is determined based on the specific identification method and any realized gains or losses on the sale of investments are reflected as a component of other income. |
Concentration of Credit Risk | Concentrations of Credit Risk —Financial instruments that potentially subject the Company to significant concentration of credit risk consist primarily of cash, cash equivalents and short-term investments. Periodically, the Company may maintain deposits in financial institutions in excess of government insured limits. We believe that we are not exposed to significant credit risk as our deposits are held at financial institutions that management believes to be of high credit quality and the Company has not experienced any losses on these deposits. We regularly invest excess cash with major financial institutions in money market funds, U.S. government and corporate debt securities and commercial paper, all of which can be readily purchased and sold using established markets. As of December 31, 2020 , the Company’s cash and cash equivalents were held with two financial institutions. We believe that the market risk arising from our holdings of these financial instruments is mitigated based on the fact that many of these securities are either government - backed or of high credit rating. |
Offering Costs | Offering Costs —The Company capitalizes incremental legal, professional accounting and other third-party fees that are directly associated with equity financings as other current assets until the transactions are completed. After equity financings are complete, these costs are recorded in stockholders’ equity as a reduction of additional paid-in capital generated as a result of the offering. |
Leases | Leases — In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which eliminated the tests for lease classification under prior U.S. GAAP and requires lessees to recognize right-of-use assets and related lease liabilities on the balance sheet. The FASB subsequently issued the following amendments to ASU 2016-02 that have the same effective date and transition date: ASU No. 2018-01 – Leases (Topic 842): Land Easement Practical Expedient for Transition to Topic 842 , ASU No. 2018-10 – Codification Improvements to Topic 842 , Leases , ASU No. 2018-11 – Leases (Topic 842): Targeted Improvements , ASU No. 2018-20 – Leases (Topic 842): Narrow-Scope Improvements for Lessors , and ASU No. 2019-01 – Leases (Topic 842): Codification Improvements . The Company adopted these amendments with ASU 2016-02 (collectively, the new leasing standards) effective January 1, 2020. The Company adopted the new leasing standards using the modified retrospective approach, as of January 1, 2020, with no restatement of prior periods or cumulative adjustments to accumulated deficit. The Company elected the package of practical expedients permitted under the transition guidance within the new standard, which, among other things, allows the Company to carry forward the historical lease classification. In addition, the Company elected the practical expedient not to apply the recognition requirements in the leasing standards to short-term leases (a lease that at commencement date has a lease term of 12 months or less and does not contain a purchase option that it is reasonably certain to exercise) and the practical expedient that permits lessees to make an accounting policy election (by class of underlying asset) to not separate lease components of a contract from non-lease components. The Company determines if an arrangement is a lease at contract inception. The Company’s contracts are determined to contain a lease when all of the following criteria based on the specific circumstances of the arrangement are met: (1) there is an identified asset for which there are no substantive substitution rights; (2) the Company has the right to obtain substantially all of the economic benefits from the identified asset; and (3) the Company has the right to direct the use of the identified asset. At the commencement date, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of future lease payments over the expected lease term. The Company’s lease agreements do not provide an implicit rate. As a result, the Company utilizes an estimated incremental borrowing rate to discount lease payments, which is based on the rate of interest the Company would have to pay to borrow a similar amount on a collateralized basis over a similar term. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or lease incentives received. Operating lease cost is recognized over the expected term on a straight-line basis. Variable lease cost is recognized as incurred. The Company acts as sublessor related to a sublease of the Company's former headquarters. Fixed sublease payments received are recognized on a straight-line basis over the sublease term. Right-of-use assets are periodically evaluated for impairment. The expected lease term for those leases commencing prior to January 1, 2020 did not change with the adoption of the new leasing standards. The expected lease term for leases commencing after the adoption of the new leasing standards includes noncancelable lease periods and, when applicable, periods covered by an option to extend the lease if the Company is reasonably certain to exercise that option, as well as periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise that option. As a result of the adoption of the new leasing standards, on January 1, 2020, the Company recorded non-cash transactions to recognize a right-of-use asset of $6.8 million, operating lease liabilities of $17.7 million and the derecognition of deferred rent of $10.9 million originally accounted for under legacy guidance. The adoption did not have a material impact on the condensed consolidated statement of operations. For additional information on the adoption of the new leasing standards, refer to Note 8. January 1, 2020 (in thousands) Prior to adoption of new leasing standards Adjustment for adoption of new leasing standards As Adjusted Right-of-use assets (1)(2) $ — $ 6,835 $ 6,835 Deferred rent (2) $ 1,313 $ (1,313 ) $ — Deferred rent, net of current portion (2) $ 9,544 $ (9,544 ) $ — Operating lease liabilities (3) $ — $ 2,251 $ 2,251 Operating lease liabilities, net of current portion (3) $ — $ 15,441 $ 15,441 (1) Represents capitalization of operating right-of-use assets (2) Represents reclassification of deferred rent and incentives as a reduction to operating right-of-use assets (3) Represents recognition of operating lease liabilities |
Guarantees and Indemnifications | Guarantees and Indemnifications —As permitted under Delaware law, the Company indemnifies its officers, directors, consultants and employees for certain events or occurrences that happen by reason of the relationship with, or position held at, the Company. Through December 31, 2020, the Company had not experienced any losses related to these indemnification obligations, and no claims 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 liabilities have been established. |
Property and Equipment | Property and Equipment —Property and equipment are recorded at cost. Expenditures for repairs and maintenance are expensed as incurred. When assets are retired or disposed of, the assets and related accumulated depreciation are derecognized from the accounts, and any resulting gain or loss is included in the determination of net loss. Depreciation is provided using the straight-line method over the estimated useful lives of the related assets. Leasehold improvements are amortized over the shorter of the lease term or the estimated useful life of the asset. Computer equipment and software 3 years Laboratory equipment and office furniture 5 years Manufacturing equipment 5 - 7 years Leasehold improvements Shorter of the lease term or estimated useful life |
Impairment of Long-Lived Assets | Impairment of Long-Lived Assets —The Company evaluates its long-lived assets, which consist primarily of property and equipment, for impairment whenever events or changes in circumstances indicate that the carrying amount of such assets may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to the future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the asset exceeds the fair value of the asset. To date, no impairments have been recognized for these assets. |
Research and Development Costs | Research and Development Costs —Research and development costs are charged to expense as incurred. Research and development expense consists of expenses incurred in performing research and development activities, including salaries and benefits, materials and supplies, preclinical and clinical expenses, stock-based compensation expense, depreciation of equipment, contract services, and other outside expenses. Costs for certain development activities are recognized based on an evaluation of the progress to completion of specific tasks using information provided to the Company by its vendors on their actual costs incurred. 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 expense or accrued research and development expense. |
Income Taxes | Income Taxes —The Company recognizes deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the Company’s consolidated financial statements and tax returns. Deferred tax assets and liabilities are determined based upon the differences between the financial statement carrying amounts and the tax bases of existing assets and liabilities and for loss and credit carryforwards, using enacted tax rates expected to be in effect in the year in which the differences are expected to reverse. Deferred tax assets are reduced by a valuation allowance if it is more likely than not that these assets may not be realized. The Company determines whether it is more likely than not that a tax position will be sustained upon examination. The tax benefit to be recognized for any tax position that meets the more-likely-than-not recognition threshold is calculated as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement. If it is not more likely than not that a position will be sustained, none of the benefit attributable to the position is recognized. The Company accounts for interest and penalties related to uncertain tax positions as part of its provision for income taxes. |
Segment Information | Segment Information —Operating segments are identified as components of an enterprise about which separate discrete financial information is made available for evaluation by the chief operating decision maker (“CODM”) in making decisions regarding resource allocation and assessing performance. The CODM is the Company’s Chief Executive Officer. The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is dedicated to translating proprietary gene editing and gene therapy technology into novel treatments for patients with rare genetic diseases. All of the Company’s tangible assets are held in the United States. |
Revenue Recognition | Revenue Recognition— Revenue is recognized in accordance with FASB Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers (“ASC 606”). On January 1, 2019, the Company adopted ASC 606 using the full retrospective transition method. Under ASC 606, the Company recognizes revenue when its customer obtains control of promised goods or services, in an amount that reflects the consideration which the entity expects to receive in exchange for those goods or services. To determine the appropriate amount of revenue to be recognized for arrangements determined to be within the scope of ASC 606, the Company performs the following five steps: (i) identification of the promised goods or services in the contract; (ii) determination of whether the promised goods or services are performance obligations including whether they are distinct in the context of the contract; (iii) measurement of the transaction price, including the constraint on variable consideration; (iv) allocation of the transaction price to the performance obligations; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect consideration it is entitled to in exchange for the goods or services it transfers to the customer. The promised goods or services in the Company’s arrangements would likely consist of a license, rights to the Company’s intellectual property or research, development and manufacturing services. Performance obligations are promised goods or services in a contract to transfer a distinct good or service to the customer and are considered distinct when (i) the customer can benefit from the good or service on its own or together with other readily available resources and (ii) the promised good or service is separately identifiable from other promises in the contract. In assessing whether promised goods or services are distinct, the Company considers factors such as the stage of development of the underlying intellectual property, the capabilities of the customer to develop the intellectual property on its own or whether the required expertise is readily available and whether the goods or services are integral or dependent to other goods or services in the contract. The Company estimates the transaction price based on the amount expected to be received for transferring the promised goods or services in the contract. The consideration may include fixed consideration and variable consideration. At the inception of each arrangement that includes variable consideration, the Company evaluates the amount of consideration to which the Company expects to be entitled to. The Company utilizes either the most likely amount method or expected value method to estimate the amount expected to be received based on which method best predicts the amount expected to be received. The amount of variable consideration that is included in the transaction price may be constrained and is included in the transaction price only to the extent that it is probable that a significant reversal in the amount of the cumulative revenue recognized will not occur in a future period. The Company’s contracts may include development and regulatory milestone payments that are assessed under the most likely amount method and constrained until it is probable that a significant revenue reversal would not occur. Milestone payments that are not within the Company’s control, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At the end of each reporting period, the Company re-evaluates the probability of achievement of such development and regulatory milestones and any related constraint, and if necessary, adjust its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect collaboration revenue in the period of adjustment. For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue 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 (or partially satisfied). To date, the Company has not recognized any royalty revenue resulting from the Company’s collaboration arrangement. The Company allocates the transaction price based on the estimated standalone selling price of each performance obligation. The Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the stand-alone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs. Variable consideration is allocated specifically to one or more performance obligations in a contract when the terms of the variable consideration relate to the satisfaction of the performance obligation and the resulting amounts allocated are consistent with the amounts the Company would expect to receive for the satisfaction of each performance obligation. The consideration allocated to each performance obligation is recognized as revenue when control is transferred for the related goods or services. For performance obligations which consist of licenses and other promises, 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. The Company evaluates the measure of progress for its over-time arrangements at each reporting period and, if necessary, updates the measure of progress and revenue recognized. |
Stock Based Compensation | Stock-based Compensation —The Company recognizes compensation expense for awards to employees based on the grant date fair value of stock-based awards on a straight-line basis over the period during which an award holder provides service in exchange for the award. The fair value of options on the date of grant is calculated using the Black-Scholes option pricing model based on key assumptions such as stock price, expected volatility and expected term. The Company’s estimates of these assumptions are primarily based on the trading price of the Company’s stock, historical data, peer company data and judgment regarding future trends and factors. Stock-based awards granted to nonemployees are initially recorded at fair value and are re-measured at each reporting period as the awards vest and expense is recognized over the period the services are provided. The purchase price of common stock under the Company’s employee stock purchase plan (“ESPP”) is equal to 85% of the lesser of (i) the fair market value per share of the common stock on the first business day of an offering period and (ii) the fair market value per share of the common stock on the purchase date. The fair value of the look-back provision under the ESPP is calculated using the Black-Scholes option pricing model. The fair value of the look-back provision plus the 15% discount is recognized as compensation expense over the 180-day purchase period. |
Fair Value Measurements | Fair Value Measurements —Certain assets and liabilities are reported on a recurring basis at fair value. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1—Quoted prices (unadjusted) in active markets for identical assets or liabilities. • Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. |
Net Loss per Share | Net Loss per Share —Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed using the weighted-average number of common shares outstanding during the period and, if dilutive, the weighted-average number of potential shares of common stock. The weighted-average number of common shares included in the computation of diluted net loss gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and unvested shares of common stock. Common stock equivalent shares are excluded from the computation of diluted net loss per share if their effect is antidilutive. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is generally the same as basic net loss per share attributable to common stockholders since dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. |
Recent Accounting Pronouncements | Recent Accounting Pronouncements —The Jumpstart Our Business Startups Act of 2012 permits an emerging growth company to take advantage of an extended transition period to comply with new or revised accounting standards applicable to public companies until those standards would otherwise apply to private companies. As an emerging growth company, the Company has elected to take advantage of this extended transition period. In February 2016, the FASB issued new leasing standards to increase transparency and comparability among organization related to their leasing activities. For additional information on the adoption of the new leasing standards, please refer to section titled “Leases” above, and Note 8. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In June 2018, the FASB issued ASU No. 2018-07, Compensation—Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting , In October 2020, the FASB issued ASU 2020-10, Codification Improvements |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Accounting Policies [Abstract] | |
Reconciliation of Cash, Cash Equivalents and Restricted Cash | The following table provides a reconciliation of cash, cash equivalents and restricted cash to amounts shown in the consolidated statements of cash flows: December 31, 2020 2019 (in thousands) Cash and cash equivalents $ 217,431 $ 53,774 Restricted cash 1,274 1,274 Total cash, cash equivalents and restricted cash $ 218,705 $ 55,048 |
Impact of Adoption of Previously Reported Amounts of Financial Statement | January 1, 2020 (in thousands) Prior to adoption of new leasing standards Adjustment for adoption of new leasing standards As Adjusted Right-of-use assets (1)(2) $ — $ 6,835 $ 6,835 Deferred rent (2) $ 1,313 $ (1,313 ) $ — Deferred rent, net of current portion (2) $ 9,544 $ (9,544 ) $ — Operating lease liabilities (3) $ — $ 2,251 $ 2,251 Operating lease liabilities, net of current portion (3) $ — $ 15,441 $ 15,441 (1) Represents capitalization of operating right-of-use assets (2) Represents reclassification of deferred rent and incentives as a reduction to operating right-of-use assets (3) Represents recognition of operating lease liabilities |
Schedule of Estimated Useful Life of Asset | Computer equipment and software 3 years Laboratory equipment and office furniture 5 years Manufacturing equipment 5 - 7 years Leasehold improvements Shorter of the lease term or estimated useful life |
Cash and Cash Equivalents (Tabl
Cash and Cash Equivalents (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Cash And Cash Equivalents [Abstract] | |
Summary of Cash and Cash Equivalents | The following table summarizes the Company’s cash and cash equivalents: December 31, 2020 2019 (in thousands) Cash $ 250 $ 250 Repurchase agreements — 14,000 Money market funds 217,181 39,524 Total cash and cash equivalents $ 217,431 $ 53,774 |
Short-Term Investments (Tables)
Short-Term Investments (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Investments Disclosure [Abstract] | |
Summary of Short Term Investments | The following table summarizes the Company’s short-term investments as of December 31, 2019: As of December 31, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair Value (in thousands) Asset-backed securities $ 14,866 $ 10 $ — $ 14,876 Commercial paper 41,259 — — 41,259 U.S. Treasury securities 59,926 45 — 59,971 Corporate debt securities 92,380 128 — 92,508 Total short-term investments $ 208,431 $ 183 $ — $ 208,614 |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Fair Value Disclosures [Abstract] | |
Schedule of Assets Measured at Fair Value on Recurring Basis | Assets measured at fair value on a recurring basis were as follows: Description December 31, 2020 Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Cash equivalents: Money market mutual funds $ 217,181 $ 217,181 $ — $ — Total financial assets $ 217,181 $ 217,181 $ — $ — Description December 31, 2019 Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1) Significant Other Observable Inputs (Level 2) Significant Unobservable Inputs (Level 3) (in thousands) Cash equivalents: Money market mutual funds $ 39,524 $ 39,524 $ — $ — Repurchase agreements 14,000 — 14,000 — Total cash equivalents $ 53,524 $ 39,524 $ 14,000 $ — Short-term investments: Asset-backed securities $ 14,876 $ — $ 14,876 $ — Commercial paper 41,259 — 41,259 — U.S. Treasury securities 59,971 — 59,971 — Corporate debt securities 92,508 — 92,508 — Total short-term investments $ 208,614 $ — $ 208,614 $ — Total financial assets $ 262,138 $ 39,524 $ 222,614 $ — |
Property and Equipment (Tables)
Property and Equipment (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Property Plant And Equipment [Abstract] | |
Schedule of Property and Equipment, Net | Property and equipment, net consists of the following: December 31, 2020 2019 (in thousands) Laboratory equipment $ 12,703 $ 10,837 Manufacturing equipment 7,754 4,911 Computers and purchased software 1,596 640 Furniture and fixtures 1,363 1,363 Leasehold improvements 29,961 30,862 Assets not yet in service — 2,513 Property and equipment, at cost 53,377 51,126 Less accumulated depreciation and amortization (16,375 ) (8,410 ) Property and equipment, net $ 37,002 $ 42,716 |
Accrued Expenses and Other Li_2
Accrued Expenses and Other Liabilities (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Payables And Accruals [Abstract] | |
Schedule of Accrued Expenses and Other Liabilities | Accrued expenses and other liabilities consist of the following: December 31, 2020 2019 (in thousands) Accrued compensation and benefits $ 6,902 $ 4,551 Accrued research and development expenses 2,393 2,258 Accrued professional fees 291 542 Accrued unvested common stock subject to repurchase 13 37 Accrued other 204 256 Total accrued expenses and other liabilities $ 9,803 $ 7,644 |
Commitments and Contingencies (
Commitments and Contingencies (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Commitments And Contingencies Disclosure [Abstract] | |
Schedule of Operating Lease Cost and Variable Lease Costs and Sub Lease Income | The following table summarizes operating lease costs and variable lease costs, as well as sublease income for the year ended December 31, 2020: Year ended December 31, 2020 Amount (in thousands) Operating lease costs $ 2,492 Variable lease costs 2,355 Sublease income (913 ) Net lease cost $ 3,934 |
Schedule of Operating Lease Liabilities | The maturities of our operating lease liabilities as of December 31, 2020 were as follows: Amount For the Years Ending December 31, (in thousands) 2021 $ 3,834 2022 2,987 2023 3,077 2024 3,169 Thereafter 7,197 Total undiscounted lease payments $ 20,264 Less: imputed interest (4,822 ) Present value of operating lease liabilities $ 15,442 |
Schedule of Lease Term and Discount Rate | The following table summarizes the lease term and discount rate as of December 31, 2020: As of December 31, 2020 Weighted-average remaining lease term (years) Operating leases 5.9 Weighted-average discount rate Operating leases 9.9 % |
Schedule of Operating Lease Liabilities | The following table summarizes the supplemental cash flow information related to the Company's operating leases for the year ended December 31, 2020. Year ended December 31, 2020 (in thousands) Cash paid for amounts included in the measurement of lease liabilities $ 3,804 |
Income Taxes (Tables)
Income Taxes (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Income Tax Disclosure [Abstract] | |
Schedule of Reconciliation between U.S. Federal Statutory Tax Rate and Effective Tax Rate | A reconciliation between the U.S. federal statutory tax rate and the Company’s effective tax rate is summarized as follows: For the Years Ended December 31, 2020 2019 Federal statutory rate 21.0 % 21.0 % Tax credits 10.6 % 13.4 % State taxes, net of federal tax benefit 8.0 % 6.1 % Non-deductible expenses (1.8 %) (1.0 %) Change in valuation allowance (37.8 %) (39.5 %) Effective income tax rate — % — % |
Schedule of Deferred Tax Assets and Liabilities | The principal components of the Company’s deferred tax assets and liabilities consist of the following: December 31, 2020 2019 (in thousands) Deferred tax assets: Net operating losses $ 72,838 $ 41,589 R&D credits 39,888 25,328 Deferred revenue 8,251 8,456 Deferred rent 4,219 2,966 Capitalized R&D costs 1,039 1,207 Equity compensation 1,368 883 Accrued expense and other 1,914 108 Total deferred tax assets 129,517 80,537 Deferred tax liabilities: Depreciation (3,726 ) (2,744 ) Other (757 ) — Total deferred tax liabilities (4,483 ) (2,744 ) Valuation allowance (125,034 ) (77,793 ) Net deferred taxes $ — $ — |
Stock Incentive Plans (Tables)
Stock Incentive Plans (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Schedule of Stock Options Valuation Assumptions Using a Black-Scholes Option Pricing Model | The assumptions used in the Black-Scholes option pricing model are as follows: For the Years Ended December 31, 2020 2019 Expected volatility 63.2% — 66.3% 62.4% — 64.7% Weighted-average risk-free interest rate 0.31% — 1.73% 1.36% — 2.60% Expected dividend yield — % — % Expected term (in years) 5.5 - 6.25 6.25 Underlying common stock fair value $9.82 - $21.75 $12.73 — $30.34 |
Schedule of Stock-Based Compensation Expense | The Company recorded stock-based compensation expense related to stock options and shares purchased under the 2018 ESPP as follows: For the Years Ended December 31, 2020 2019 (in thousands) Research and development $ 6,390 $ 4,164 General and administrative 6,858 3,471 $ 13,248 $ 7,635 |
Summary of Option Activity under Plans | A summary of option activity under the Plans during the year ended December 31, 2020 is as follows: Number of Options Weighted- Average Exercise Price per Share Weighted- Average Remaining Contractual Term (in Years) Aggregate Intrinsic Value (in thousands) Outstanding at January 1, 2020 4,843,018 $ 14.78 8.5 $ 33,809 Granted 1,311,200 $ 17.82 Exercised (46,410 ) $ 3.79 Cancelled/Forfeited (266,984 ) $ 22.75 Outstanding at December 31, 2020 5,840,824 $ 15.18 7.8 $ 12,278 Vested and expected to vest at December 31, 2020 5,840,824 $ 15.18 7.8 $ 12,278 Exercisable at December 31, 2020 2,869,589 $ 12.18 7.0 $ 10,803 |
Summary of Unvested Common Stock from Early Exercises Subject to Repurchase | A summary of the Company’s unvested common stock from early exercises that is subject to repurchase by the Company is as follows: Shares Unvested shares—January 1, 2020 21,666 Vested (18,575 ) Issued — Repurchased — Unvested shares—December 31, 2020 3,091 |
Net Loss Per Share (Tables)
Net Loss Per Share (Tables) | 12 Months Ended |
Dec. 31, 2020 | |
Earnings Per Share [Abstract] | |
Schedule of Anti-dilutive Effect Excluded from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders | The Company excluded the following potential common shares, presented based on amounts outstanding at December 31, 2020 and 2019 , from the computation of diluted net loss per share attributable to common stockholders because including them would have had an anti-dilutive effect: As of December 31, 2020 2019 Unvested common stock from early exercise of options 3,091 21,666 Stock options to purchase common stock 5,840,824 4,843,018 Total 5,843,915 4,864,684 |
Nature of Business and Basis _2
Nature of Business and Basis of Presentation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | Nov. 09, 2020 | Mar. 12, 2020 | Apr. 30, 2019 | Apr. 12, 2019 | Apr. 02, 2018 | Nov. 09, 2020 | Dec. 31, 2020 | Dec. 31, 2019 |
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Conversion of convertible preferred stock into common stock upon initial public offering, Shares | 24,168,656 | |||||||
Common Stock, capacity terminated | $ 76,800 | |||||||
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs | $ 134,524 | |||||||
Net loss | $ 128,694 | 103,916 | ||||||
Accumulated deficit | 328,368 | $ 199,674 | ||||||
Initial Public Offering | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 10,350,000 | |||||||
Common stock at a public offering price | $ 16 | |||||||
Net proceeds from initial public offering after underwriting discounts and commissions and offering expenses | $ 150,800 | |||||||
Follow On Offering | Common Stock | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 5,555,556 | 6,388,889 | ||||||
Shares issued price per share | $ 22.50 | |||||||
Net proceeds after deducting underwriting discounts and commissions and offering expenses | $ 116,900 | |||||||
Underwriters Option | Common Stock | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 833,333 | |||||||
Shares issued price per share | $ 22.50 | |||||||
Net proceeds after deducting underwriting discounts and commissions and offering expenses | $ 17,600 | |||||||
ATM | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Proceeds through future financings | $ 150,000 | |||||||
ATM | Maximum | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Proceeds through future financings | $ 150,000 | $ 100,000 | ||||||
ATM | Common Stock | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 0 | 1,105,000 | ||||||
Private Placement | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 5,000,000 | 5,000,000 | ||||||
Shares issued price per share | $ 12 | $ 12 | ||||||
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs | $ 60,000 | $ 60,000 | ||||||
Private Placement | Common Stock | ||||||||
Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] | ||||||||
Issuance of common stock, net of discounts and issuance costs, Shares | 5,000,000 |
Summary of Significant Accoun_4
Summary of Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Accounting Policies [Abstract] | ||
Cash and cash equivalents | $ 217,431 | $ 53,774 |
Restricted cash | 1,274 | 1,274 |
Total cash, cash equivalents and restricted cash | $ 218,705 | $ 55,048 |
Summary of Significant Accoun_5
Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) | 3 Months Ended | 12 Months Ended | ||
Mar. 31, 2020 | Dec. 31, 2020 | Jan. 01, 2020 | ||
Summary Of Significant Accounting Policies [Line Items] | ||||
Right-of-use assets | $ 5,897,000 | $ 6,835,000 | [1],[2] | |
Operating lease liabilities | 15,442,000 | 2,251,000 | [3] | |
Outstanding claim | 0 | |||
Impairment of long-lived assets | $ 0 | |||
Tax positions, description | The Company determines whether it is more likely than not that a tax position will be sustained upon examination. The tax benefit to be recognized for any tax position that meets the more-likely-than-not recognition threshold is calculated as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate settlement. If it is not more likely than not that a position will be sustained, none of the benefit attributable to the position is recognized. | |||
Employee Stock Purchase Plan | ||||
Summary Of Significant Accounting Policies [Line Items] | ||||
Purchase of common stock through payroll deductions expressed in percentage of fair market value | 85.00% | 85.00% | ||
Share based compensation, discount from market price | 15.00% | |||
Share based compensation arrangement by share based payment purchase period | 180 days | |||
ASU 2016-02 | ||||
Summary Of Significant Accounting Policies [Line Items] | ||||
Right-of-use assets | 6,800,000 | |||
Operating lease liabilities | 17,700,000 | |||
Deferred rent | $ 10,900,000 | |||
[1] | Represents capitalization of operating right-of-use assets | |||
[2] | Represents reclassification of deferred rent and incentives as a reduction to operating right-of-use assets | |||
[3] | Represents recognition of operating lease liabilities |
Summary of Significant Accoun_6
Summary of Significant Accounting Policies - Impact of Adoption of Previously Reported Amounts of Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Jan. 01, 2020 | Dec. 31, 2019 | ||
Right-of-use assets | $ 5,897 | $ 6,835 | [1],[2] | ||
Deferred rent | $ 1,313 | ||||
Operating lease liabilities | 15,442 | 2,251 | [3] | ||
Operating lease liabilities | $ 2,501 | 15,441 | [3] | ||
Prior to Adoption of New Leasing Standards | |||||
Deferred rent | [2] | 1,313 | |||
Deferred rent | [2] | 9,544 | |||
Adjustment for Adoption of New Leasing Standards | |||||
Right-of-use assets | [1],[2] | 6,835 | |||
Deferred rent | [2] | 1,313 | |||
Deferred rent | [2] | (9,544) | |||
Operating lease liabilities | [3] | 2,251 | |||
Operating lease liabilities | [3] | $ 15,441 | |||
[1] | Represents capitalization of operating right-of-use assets | ||||
[2] | Represents reclassification of deferred rent and incentives as a reduction to operating right-of-use assets | ||||
[3] | Represents recognition of operating lease liabilities |
Summary of Significant Accoun_7
Summary of Significant Accounting Policies - Schedule of Estimated Useful Life of Asset (Details) | 12 Months Ended |
Dec. 31, 2020 | |
Computer Equipment and Software | |
Property Plant And Equipment [Line Items] | |
Estimated useful life of asset | 3 years |
Laboratory Equipment and Office Furniture | |
Property Plant And Equipment [Line Items] | |
Estimated useful life of asset | 5 years |
Manufacturing Equipment | Minimum | |
Property Plant And Equipment [Line Items] | |
Estimated useful life of asset | 5 years |
Manufacturing Equipment | Maximum | |
Property Plant And Equipment [Line Items] | |
Estimated useful life of asset | 7 years |
Leasehold Improvements | |
Property Plant And Equipment [Line Items] | |
Estimated useful life of asset, term | Shorter of the lease term or estimated useful life |
Summary of Cash and Cash Equiva
Summary of Cash and Cash Equivalents (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Cash And Cash Equivalents [Line Items] | ||
Total cash and cash equivalents | $ 217,431 | $ 53,774 |
Cash | ||
Cash And Cash Equivalents [Line Items] | ||
Total cash and cash equivalents | 250 | 250 |
Money Market Funds | ||
Cash And Cash Equivalents [Line Items] | ||
Total cash and cash equivalents | $ 217,181 | 39,524 |
Repurchase Agreements | ||
Cash And Cash Equivalents [Line Items] | ||
Total cash and cash equivalents | $ 14,000 |
Short-Term Investments - Additi
Short-Term Investments - Additional Information (Details) - USD ($) | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Cash Cash Equivalents And Available For Sale Securities [Abstract] | ||
Short-term investments | $ 0 | $ 208,614,000 |
Realized gains and losses on available-for-sale securities | $ 0 | $ 0 |
Contractual maturity date of investments | Less than one year |
Short-Term Investments - Summar
Short-Term Investments - Summary of Short Term Investments (Details) $ in Thousands | Dec. 31, 2019USD ($) |
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items] | |
Cash equivalents and short-term investments, Amortized Cost | $ 208,431 |
Cash equivalents and short-term investments, Unrealized Gains | 183 |
Cash equivalents and short-term investments, Fair Value | 208,614 |
Commercial Paper | |
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items] | |
Cash equivalents and short-term investments, Amortized Cost | 41,259 |
Cash equivalents and short-term investments, Fair Value | 41,259 |
Asset-backed Securities | |
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items] | |
Cash equivalents and short-term investments, Amortized Cost | 14,866 |
Cash equivalents and short-term investments, Unrealized Gains | 10 |
Cash equivalents and short-term investments, Fair Value | 14,876 |
U.S Treasury Securities | |
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items] | |
Cash equivalents and short-term investments, Amortized Cost | 59,926 |
Cash equivalents and short-term investments, Unrealized Gains | 45 |
Cash equivalents and short-term investments, Fair Value | 59,971 |
Corporate Debt Securities | |
Schedule Of Cash Cash Equivalents And Available For Sale Securities [Line Items] | |
Cash equivalents and short-term investments, Amortized Cost | 92,380 |
Cash equivalents and short-term investments, Unrealized Gains | 128 |
Cash equivalents and short-term investments, Fair Value | $ 92,508 |
Fair Value Measurements - Sched
Fair Value Measurements - Schedule of Assets Measured at Fair Value on Recurring Basis (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019 |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | $ 0 | $ 208,614,000 |
Fair Value, Measurements, Recurring | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 53,524,000 | |
Financial assets, fair value | 217,181,000 | 262,138,000 |
Repurchase agreements | 53,524,000 | |
Short-term investments | 208,614,000 | |
Fair Value, Measurements, Recurring | Money Market Mutual Funds | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 217,181,000 | 39,524,000 |
Repurchase agreements | 217,181,000 | 39,524,000 |
Fair Value, Measurements, Recurring | Asset-backed Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | 14,876,000 | |
Fair Value, Measurements, Recurring | Commercial Paper | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 41,259,000 | |
Repurchase agreements | 41,259,000 | |
Fair Value, Measurements, Recurring | Corporate Debt Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | 92,508,000 | |
Fair Value, Measurements, Recurring | U.S Treasury Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | 59,971,000 | |
Fair Value, Measurements, Recurring | Repurchase Agreements | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 14,000,000 | |
Repurchase agreements | 14,000,000 | |
Fair Value, Measurements, Recurring | Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1) | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 39,524,000 | |
Financial assets, fair value | 217,181,000 | 39,524,000 |
Repurchase agreements | 39,524,000 | |
Fair Value, Measurements, Recurring | Quoted Prices (Unadjusted) in Active Markets for Identical Assets (Level 1) | Money Market Mutual Funds | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 217,181,000 | 39,524,000 |
Repurchase agreements | $ 217,181,000 | 39,524,000 |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 14,000,000 | |
Financial assets, fair value | 222,614,000 | |
Repurchase agreements | 14,000,000 | |
Short-term investments | 208,614,000 | |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Asset-backed Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | 14,876,000 | |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Commercial Paper | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 41,259,000 | |
Repurchase agreements | 41,259,000 | |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate Debt Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | 92,508,000 | |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S Treasury Securities | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Short-term investments | 59,971,000 | |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Repurchase Agreements | ||
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] | ||
Cash equivalents, fair value | 14,000,000 | |
Repurchase agreements | $ 14,000,000 |
Fair Value Measurements - Addit
Fair Value Measurements - Additional Information (Details) - USD ($) | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Fair Value Disclosures [Abstract] | ||
Transfers between fair value measure levels | $ 0 | $ 0 |
Property and Equipment - Schedu
Property and Equipment - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | $ 53,377 | $ 51,126 |
Less accumulated depreciation and amortization | (16,375) | (8,410) |
Property and equipment, net | 37,002 | 42,716 |
Laboratory Equipment | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | 12,703 | 10,837 |
Manufacturing Equipment | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | 7,754 | 4,911 |
Computers and Purchased Software | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | 1,596 | 640 |
Furniture and Fixtures | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | 1,363 | 1,363 |
Leasehold Improvements | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | $ 29,961 | 30,862 |
Assets Not Yet in Service | ||
Property Plant And Equipment [Line Items] | ||
Property and equipment, at cost | $ 2,513 |
Property and Equipment - Additi
Property and Equipment - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Property Plant And Equipment [Line Items] | ||
Depreciation | $ 7,965 | $ 6,318 |
Disposal of property and equipment | $ 900 | |
Maximum | ||
Property Plant And Equipment [Line Items] | ||
Disposal of property and equipment | $ 100 |
Accrued Expenses and Other Li_3
Accrued Expenses and Other Liabilities - Schedule of Accrued Expenses and Other Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Payables And Accruals [Abstract] | ||
Accrued compensation and benefits | $ 6,902 | $ 4,551 |
Accrued research and development expenses | 2,393 | 2,258 |
Accrued professional fees | 291 | 542 |
Accrued unvested common stock subject to repurchase | 13 | 37 |
Accrued other | 204 | 256 |
Total accrued expenses and other liabilities | $ 9,803 | $ 7,644 |
Commitments and Contingencies -
Commitments and Contingencies - Additional Information (Details) | 1 Months Ended | 12 Months Ended | ||
Dec. 31, 2017ft²Phase$ / ft² | Sep. 30, 2016 | Dec. 31, 2019USD ($) | Dec. 31, 2020USD ($) | |
Commitment And Contingencies [Line Items] | ||||
Rent expense | $ 1,400,000 | |||
Letters of Credit and Secured by Restricted Cash | ||||
Commitment And Contingencies [Line Items] | ||||
Security deposit | $ 1,300,000 | $ 1,300,000 | ||
Maximum | ||||
Commitment And Contingencies [Line Items] | ||||
Tenant improvement allowance | 10,900,000 | |||
Bedford, Massachusetts | ||||
Commitment And Contingencies [Line Items] | ||||
Operating lease beginning year and month | 2016-11 | |||
Operating lease expiration year and month | 2027-02 | 2021-10 | ||
Operating lease agreements additional term | 3 years | |||
Sublease aggregate base rent obligation | $ 2,700,000 | |||
Office space leased | ft² | 67,000 | |||
Lessee, operating lease, lease not yet commenced, renewal term | 5 years | |||
Number of phases | Phase | 2 | |||
Initial annual base rent per square foot | $ / ft² | 39.50 | |||
Percentage increase in initial annual base rent per square foot. | 3.00% | |||
Bedford, Massachusetts | Phase One | ||||
Commitment And Contingencies [Line Items] | ||||
Office space leased | ft² | 46,000 | |||
Rent due date | 2018-09 | |||
Bedford, Massachusetts | Phase Two | ||||
Commitment And Contingencies [Line Items] | ||||
Office space leased | ft² | 21,000 | |||
Rent due date | 2019-03 |
Commitments and Contingencies_2
Commitments and Contingencies - Schedule of Operating Lease Cost and Variable Lease Costs and Sub Lease Income (Details) $ in Thousands | 12 Months Ended |
Dec. 31, 2020USD ($) | |
Commitments And Contingencies Disclosure [Abstract] | |
Operating lease costs | $ 2,492 |
Variable lease costs | 2,355 |
Sublease income | (913) |
Net lease cost | $ 3,934 |
Commitments and Contingencies_3
Commitments and Contingencies - Schedule of Operating Lease Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Jan. 01, 2020 | [1] |
Commitments And Contingencies Disclosure [Abstract] | |||
2021 | $ 3,834 | ||
2022 | 2,987 | ||
2023 | 3,077 | ||
2024 | 3,169 | ||
Thereafter | 7,197 | ||
Total undiscounted lease payments | 20,264 | ||
Less: imputed interest | (4,822) | ||
Operating lease liabilities | $ 15,442 | $ 2,251 | |
[1] | Represents recognition of operating lease liabilities |
Commitments and Contingencies_4
Commitments and Contingencies - Schedule of Lease Term and Discount Rate (Details) | Dec. 31, 2020 |
Commitments And Contingencies Disclosure [Abstract] | |
Weighted-average remaining lease term (years), Operating leases | 5 years 10 months 24 days |
Weighted-average discount rate, Operating leases | 9.90% |
Commitments and Contingencies_5
Commitments and Contingencies - Summary of Cash Paid for Company's Operating Lease Liabilities (Details) $ in Thousands | 12 Months Ended |
Dec. 31, 2020USD ($) | |
Commitments And Contingencies Disclosure [Abstract] | |
Cash paid for amounts included in the measurement of lease liabilities | $ 3,804 |
License Agreements - Additional
License Agreements - Additional Information (Details) - USD ($) | 1 Months Ended | 12 Months Ended | |||
Sep. 30, 2016 | Apr. 30, 2016 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2017 | |
License Agreement [Line Items] | |||||
Research and development | $ 100,392,000 | $ 89,398,000 | |||
City of Hope | |||||
License Agreement [Line Items] | |||||
Annual license fee | $ 25,000 | ||||
Payment for execution of agreements | $ 75,000 | 50,000 | $ 4,500,000 | ||
City of Hope | Sponsored Research Agreement | |||||
License Agreement [Line Items] | |||||
Research and development | $ 100,000 | ||||
City of Hope | Maximum | |||||
License Agreement [Line Items] | |||||
Development and commercialization milestone payment | $ 3,200,000 | ||||
California Institute Of Technology | Maximum | Co Exclusive License Agreement | |||||
License Agreement [Line Items] | |||||
Development and regulatory milestone payments | $ 7,200,000 | ||||
California Institute Of Technology | Minimum | Co Exclusive License Agreement | |||||
License Agreement [Line Items] | |||||
Annual minimal royalty fee | $ 20,000 |
Income Taxes - Schedule of Reco
Income Taxes - Schedule of Reconciliation between U.S. Federal Statutory Tax Rate and Effective Tax Rate (Details) | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Income Tax Disclosure [Abstract] | ||
Federal statutory rate | 21.00% | 21.00% |
Tax credits | 10.60% | 13.40% |
State taxes, net of federal tax benefit | 8.00% | 6.10% |
Non-deductible expenses | (1.80%) | (1.00%) |
Change in valuation allowance | (37.80%) | (39.50%) |
Income Taxes - Schedule of Defe
Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019 |
Deferred tax assets: | ||
Net operating losses | $ 72,838 | $ 41,589 |
R&D credits | 39,888 | 25,328 |
Deferred revenue | 8,251 | 8,456 |
Deferred rent | 4,219 | 2,966 |
Capitalized R&D costs | 1,039 | 1,207 |
Equity compensation | 1,368 | 883 |
Accrued expense and other | 1,914 | 108 |
Total deferred tax assets | 129,517 | 80,537 |
Deferred tax liabilities: | ||
Depreciation | (3,726) | (2,744) |
Other | (757) | |
Total deferred tax liabilities | (4,483) | (2,744) |
Valuation allowance | $ (125,034) | $ (77,793) |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Details) - USD ($) | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Income Tax Disclosure [Line Items] | ||
Income tax expense | $ 0 | $ 0 |
Increase in valuation allowance due to deferred tax assets | 47,200,000 | 40,200,000 |
Uncertain tax positions | 0 | |
Income tax expense, interest or penalties | $ 0 | 0 |
Orphan Drug | ||
Income Tax Disclosure [Line Items] | ||
Tax credit carryforwards | 29,000,000 | |
Tax credit carryforwards expiration year | 2040 | |
Federal | ||
Income Tax Disclosure [Line Items] | ||
Net operating loss carryforwards | $ 265,100,000 | |
Net operating loss carryforwards indefinitely | $ 233,600,000 | |
Federal | Research and Development | ||
Income Tax Disclosure [Line Items] | ||
Tax credit carryforwards | 34,200,000 | |
State | ||
Income Tax Disclosure [Line Items] | ||
Net operating loss carryforwards | 271,500,000 | |
State | Research and Development | ||
Income Tax Disclosure [Line Items] | ||
Tax credit carryforwards | $ 7,200,000 | |
Federal and State | ||
Income Tax Disclosure [Line Items] | ||
Net operating loss carryforwards expiration year | 2040 | |
Federal and State | Research and Development | ||
Income Tax Disclosure [Line Items] | ||
Tax credit carryforwards expiration year | 2040 |
Stockholders' Equity - Addition
Stockholders' Equity - Additional Information (Details) - shares | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Equity [Abstract] | ||
Common stock, voting rights | Each holder of outstanding shares of common stock are entitled to one vote in respect of each share. | |
Common stock, shares outstanding | 50,265,575 | 45,116,742 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Stock Incentive Plans - Additio
Stock Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | Jan. 01, 2021 | Mar. 31, 2018 | Mar. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019 |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Aggregate proceeds from shares issued under the plan | $ 938 | $ 829 | |||
Stock-based compensation | 13,248 | 7,635 | |||
Total intrinsic value of options exercised | $ 600 | $ 1,900 | |||
Weighted-average grant date fair value per share for options granted | $ 10.39 | $ 12.90 | |||
Remaining shares subject to repurchase | 3,091 | 21,666 | |||
Liability for unvested common shares subject to repurchase included in accrued expenses and other liabilities | $ 13 | $ 37 | |||
Accrued Expenses and Other Liabilities | Maximum | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Liability for unvested common shares subject to repurchase included in accrued expenses and other liabilities | $ 100 | $ 100 | |||
2015 Stock Incentive Plan | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Stock option vesting period | 4 years | ||||
Stock options expiration period | 10 years | ||||
Number of additional shares available for future grant | 0 | ||||
2018 Incentive Award Plan | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Number of shares available for issuance | 3,186,205 | ||||
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock | 4.00% | ||||
Maximum shares of common stock may be issued | 20,887,347 | ||||
Number of shares outstanding available for future grant | 2,397,547 | ||||
2018 Incentive Award Plan | Subsequent Event | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock | 4.00% | ||||
Number of additional shares added to the plan | 2,010,623 | ||||
2018 Employee Stock Purchase Plan | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Number of shares available for issuance | 353,980 | ||||
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock | 1.00% | ||||
Number of shares outstanding available for future grant | 1,039,650 | ||||
Maximum shares allowed to be issued under ESPP | 4,778,738 | ||||
Purchase of common stock through payroll deductions expressed in percentage of fair market value | 85.00% | 85.00% | |||
Common stock offering period | 6 months | ||||
Number of shares issued to the plan | 83,848 | 55,234 | |||
Aggregate proceeds from shares issued under the plan | $ 900 | $ 800 | |||
Stock-based compensation | 200 | $ 200 | |||
2018 Employee Stock Purchase Plan | Subsequent Event | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Allowed annual percentage increase in shares authorized as percentage of outstanding shares of common stock | 1.00% | ||||
Number of additional shares added to the plan | 502,655 | ||||
2015 and 2018 Stock Incentive Plans | |||||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |||||
Unrecognized compensation expense | $ 29,200 | ||||
Unrecognized compensation expense estimated to be recognized over period | 2 years 4 months 24 days |
Stock Incentive Plans - Schedul
Stock Incentive Plans - Schedule of Stock Options Valuation Assumptions Using a Black-Scholes Option Pricing Model (Details) - $ / shares | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Expected volatility, minimum | 63.20% | 62.40% |
Expected volatility, maximum | 66.30% | 64.70% |
Weighted-average risk-free interest rate, minimum | 0.31% | 1.36% |
Weighted-average risk-free interest rate, maximum | 1.73% | 2.60% |
Minimum | ||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Expected term (in years) | 5 years 6 months | 6 years 3 months |
Underlying common stock fair value | $ 9.82 | $ 12.73 |
Maximum | ||
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | ||
Expected term (in years) | 6 years 3 months | |
Underlying common stock fair value | $ 21.75 | $ 30.34 |
Stock Incentive Plans - Sched_2
Stock Incentive Plans - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||
Share-based compensation expense | $ 13,248 | $ 7,635 |
Research and Development | ||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||
Share-based compensation expense | 6,390 | 4,164 |
General and Administrative | ||
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] | ||
Share-based compensation expense | $ 6,858 | $ 3,471 |
Stock Incentive Plans - Summary
Stock Incentive Plans - Summary of Option Activity under Plans (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] | ||
Number of Options, Outstanding at Beginning Balance | 4,843,018 | |
Number of Options, Granted | 1,311,200 | |
Number of Options, Exercised | (46,410) | |
Number of Options, Cancelled/Forfeited | (266,984) | |
Number of Options, Outstanding at Ending Balance | 5,840,824 | 4,843,018 |
Number of Options, Vested and Expected to vest at December 31, 2019 | 5,840,824 | |
Number of Options, Exercisable at December 31, 2019 | 2,869,589 | |
Weighted-Average Exercise Price per Share, Outstanding at Beginning Balance | $ 14.78 | |
Weighted-Average Exercise Price per Share, Granted | 17.82 | |
Weighted-Average Exercise Price per Share, Exercised | 3.79 | |
Weighted-Average Exercise Price per Share, Cancelled/Forfeited | 22.75 | |
Weighted-Average Exercise Price per Share, Outstanding at Ending Balance | 15.18 | $ 14.78 |
Weighted-Average Exercise Price per Share, Vested and Expected to vest at December 31, 2019 | 15.18 | |
Weighted-Average Exercise Price Per Share, Exercisable at December 31, 2019 | $ 12.18 | |
Weighted Average Remaining Contractual Term, Outstanding | 7 years 9 months 18 days | 8 years 6 months |
Weighted Average Remaining Contractual Term, Vested and Expected to vest at December 31, 2019 | 7 years 9 months 18 days | |
Weighted Average Remaining Contractual Term, Exercisable at December 31, 2019 | 7 years | |
Aggregate Intrinsic Value, Outstanding Beginning Balance | $ 12,278 | $ 33,809 |
Aggregate Intrinsic Value, Vested and Expected to vest at December 31, 2019 | 12,278 | |
Aggregate Intrinsic Value, Exercisable at December 31, 2019 | $ 10,803 |
Stock Incentive Plans - Summa_2
Stock Incentive Plans - Summary of Unvested Common Stock from Early Exercises Subject to Repurchase (Details) | 12 Months Ended |
Dec. 31, 2020shares | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Unvested shares, Beginning Balance | 21,666 |
Vested | (18,575) |
Unvested shares, Ending Balance | 3,091 |
Net Loss Per Share - Schedule o
Net Loss Per Share - Schedule of Anti-dilutive Effect Excluded from Computation of Diluted Net Loss Per Share Attributable to Common Stockholders (Details) - shares | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Antidilutive securities excluded from computation of diluted net loss per share | 5,843,915 | 4,864,684 |
Unvested Common Stock from Early Exercise of Options | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Antidilutive securities excluded from computation of diluted net loss per share | 3,091 | 21,666 |
Stock Options to Purchase Common Stock | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Antidilutive securities excluded from computation of diluted net loss per share | 5,840,824 | 4,843,018 |
Defined Contribution Plan - Add
Defined Contribution Plan - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended | |
Dec. 31, 2020 | Dec. 31, 2019 | |
Compensation And Retirement Disclosure [Abstract] | ||
Discretionary match made under the 401(k) Plan by employer | $ 0.7 | $ 0.5 |
Collaboration and License Agr_2
Collaboration and License Agreement - Additional Information (Details) | 1 Months Ended | 12 Months Ended | ||||
Nov. 30, 2017USD ($)CandidateorProduct | Jul. 31, 2017USD ($) | Dec. 31, 2020USD ($) | Dec. 31, 2019USD ($) | Jan. 01, 2020USD ($) | Jan. 01, 2019USD ($) | |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Collaboration agreement revenue recognized | $ 2,702,000 | $ 1,666,000 | ||||
Novartis | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Upfront, nonrefundable payment received | $ 35,000,000 | |||||
Allocated to collaboration agreement | 33,300,000 | |||||
Collaborative agreement target fee | $ 5,000,000 | |||||
Collaboration agreement, research term | 5 years | |||||
Novartis | Collaborative Arrangement | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Collaboration agreement revenue recognized | 2,300,000 | 1,700,000 | ||||
Deferred revenue | 30,200,000 | 31,000,000 | $ 800,000 | $ 600,000 | ||
Novartis | Collaborative Arrangement | Reimbursable Research and Development Costs | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Accounts receivable | 400,000 | $ 400,000 | ||||
Novartis | ASC 606 | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Transaction price | $ 33,300,000 | |||||
Novartis | Maximum | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Collaboration agreement, reimbursement of manufacturing activities during research term | $ 17,000,000 | |||||
Collaboration agreement number of candidates or products for develop and commercialize | CandidateorProduct | 1 | |||||
Collaboration agreement eligible milestone payments eligible to receive | $ 265,000,000 | |||||
Collaboration agreement eligible development milestone payments eligible to receive | 90,000,000 | |||||
Collaboration agreement eligible regulatory milestone payments eligible to receive | 85,000,000 | |||||
Collaboration agreement eligible commercial milestone payments eligible to receive | 90,000,000 | |||||
Novartis | Series B Preferred Stock | ||||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||||
Upfront, nonrefundable payment received | 1,700,000 | |||||
Proceeds from issuance of shares of preferred stock | 10,000,000 | $ 5,000,000 | ||||
Preferred stock estimated fair value | $ 11,700,000 |
Collaboration and License Agr_3
Collaboration and License Agreement - Additional Information (Details1) - Novartis $ in Millions | Dec. 31, 2020USD ($) |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2017-11-01 | |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |
Remaining performance obligation, unsatisfied portion | $ 30.2 |
Remaining performance obligation, expected timing of satisfaction, period | 10 years |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date: 2027-04-01 | |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | |
Remaining performance obligation, unsatisfied portion | $ 30.2 |
Remaining performance obligation, expected timing of satisfaction, period | 10 years |
Pfizer Stock Purchase Agreeme_2
Pfizer Stock Purchase Agreement - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands | Nov. 09, 2020 | Nov. 09, 2020 | Dec. 31, 2020 | Dec. 31, 2019 |
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs | $ 134,524 | |||
Collaboration agreement revenue recognized | $ 2,702 | $ 1,666 | ||
Pfizer Inc. | ||||
Common stock estimated fair value | $ 52,000 | $ 52,000 | ||
Stock purchase agreement remaining allocated value | 8,000 | 8,000 | ||
Allocated Information Committee obligation | $ 8,000 | $ 8,000 | ||
Pfizer Inc. | Collaborative Arrangement | ||||
Collaboration agreement revenue recognized | 400 | |||
Deferred revenue | $ 7,600 | |||
Private Placement | ||||
Issuance of common stock, net of discounts and issuance costs, Shares | 5,000,000 | 5,000,000 | ||
Shares issued price per share | $ 12 | $ 12 | ||
Proceeds from issuance of common stock in follow-on public offering, net of discounts and issuance costs | $ 60,000 | $ 60,000 | ||
Common stock purchase agreement condition | The shares of common stock sold to Pfizer are subject to a one-year lock-up from closing, during which time Pfizer is prohibited from selling or otherwise disposing of such shares. |