Cymabay Therapeutics (CBAY) 10-K 23 Mar 23 2022 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2022	Mar. 15, 2023	Jun. 30, 2022
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Trading Symbol	CBAY
Entity Registrant Name	CYMABAY THERAPEUTICS, INC.
Entity Central Index Key	0001042074
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		97,293,397
Entity Shell Company	false
Entity File Number	001-36500
Entity Tax Identification Number	94-3103561
Entity Address, Address Line One	7575 Gateway Blvd
Entity Address, Address Line Two	Suite 110
Entity Address, City or Town	Newark
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94560
City Area Code	510
Local Phone Number	293-8800
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common stock, $0.0001 par value per share
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Annual Report	true
Document Transition Report	false
Entity Public Float			$ 218,053,044
ICFR Auditor Attestation Flag	false
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	San Mateo, California

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 20,291	$ 125,806
Marketable securities	115,194	60,729
Prepaid expenses and other current assets	2,588	4,564
Total current assets	138,073	191,099
Property and equipment, net	701	1,178
Non-current marketable securities	0	8,067
Operating lease right-of-use asset	169	254
Other assets	2,909	1,720
Total assets	141,852	202,318
Current liabilities:
Accounts payable	1,096	2,728
Accrued research and development expenses	6,530	9,752
Other accrued liabilities	7,815	5,886
Total current liabilities	15,441	18,366
Development financing liability	90,227	50,320
Long-term portion of operating lease liability	30	695
Total liabilities	105,698	69,381
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.0001 par value: 10,000,000 shares authorized; no shares issued and outstanding
Common stock, $0.0001 par value: 200,000,000 shares authorized; 84,681,063 and 84,677,939 shares issued and outstanding as of December 31, 2022 and December 31, 2021, respectively	8	8
Additional paid-in capital	909,329	899,798
Accumulated other comprehensive loss	(326)	(13)
Accumulated deficit	(872,857)	(766,856)
Total stockholders' equity	36,154	132,937
Total liabilities and stockholders' equity	$ 141,852	$ 202,318

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
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	84,681,063	84,677,939
Common stock, shares outstanding	84,681,063	84,677,939

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating expenses:
Research and development	$ 67,995	$ 64,542
General and administrative	25,116	23,040
Total operating expenses	93,111	87,582
Loss from operations	(93,111)	(87,582)
Interest expense, net:
Interest income	2,017	167
Interest expense	(14,907)	(2,583)
Total interest expense, net	(12,890)	(2,416)
Net loss	(106,001)	(89,998)
Other comprehensive loss:
Unrealized loss on marketable securities, net of tax	(313)	(21)
Total other comprehensive loss	(313)	(21)
Comprehensive loss	$ (106,314)	$ (90,019)
Basic net loss per common share	$ (1.21)	$ (1.27)
Diluted net loss per common share	$ (1.21)	$ (1.27)
Weighted average common shares outstanding used to calculate basic net loss per common share	87,804,063	71,055,331
Weighted average common shares outstanding used to calculate diluted net loss per common share	87,804,063	71,055,331

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]
Balance at beginning of period at Dec. 31, 2020	$ 142,706	$ 7	$ 819,549	$ 8	$ (676,858)
Balance at beginning of period (in shares) at Dec. 31, 2020		68,946,092
Issuance of common stock upon exercise of stock options	219		219
Issuance of common stock upon exercise of stock options (Shares)		106,847
Stock-based compensation expense	9,996		9,996
Issuance of common stock and pre-funded warrants, net of issuance costs	70,035	$ 1	70,034
Issuance of common stock and pre-funded warrants, net of issuance costs Shares		15,625,000
Net loss	(89,998)				(89,998)
Net unrealized loss on marketable securities	(21)			(21)
Balance at end of period at Dec. 31, 2021	132,937	$ 8	899,798	(13)	(766,856)
Balance at end of period (in shares) at Dec. 31, 2021		84,677,939
Issuance of common stock upon exercise of stock options	$ 9		9
Issuance of common stock upon exercise of stock options (Shares)	3,124	3,124
Stock-based compensation expense	$ 9,517		9,517
Issuance costs related to issuance of common stock and pre-funded warrants	5		5
Net loss	(106,001)				(106,001)
Net unrealized loss on marketable securities	(313)			(313)
Balance at end of period at Dec. 31, 2022	$ 36,154	$ 8	$ 909,329	$ (326)	$ (872,857)
Balance at end of period (in shares) at Dec. 31, 2022		84,681,063

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity (Parenthetical) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
Statement of Stockholders' Equity [Abstract]
Stock issuance cost	$ 4,965

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating activities
Net loss	$ (106,001)	$ (89,998)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	710	688
Stock-based compensation expense	9,517	9,996
Write-off of deferred financing costs	0	312
Accretion of development financing liability	14,907	2,583
Net accretion and amortization of investments in marketable securities	(874)	637
Changes in assets and liabilities:
Prepaid expenses and other current assets	1,976	386
Other assets	(1,189)	(1,513)
Accounts payable	(1,444)	2,309
Accrued research and development expenses	(3,222)	5,054
Other accrued liabilities	1,540	115
Net cash (used in) operating activities	(84,080)	(69,431)
Investing activities
Purchases of property and equipment	(148)	(87)
Purchases of marketable securities	(174,977)	(78,084)
Proceeds from maturities of marketable securities	129,140	126,760
Net cash (used in) provided by investing activities	(45,985)	48,589
Financing activities
Proceeds from issuance of common stock pursuant to equity award plans	9	219
Proceeds from issuance of common stock and pre-funded warrants, net of issuance costs	(459)	70,499
Proceeds from development financing, net of transaction costs	25,000	47,737
Net cash provided by financing activities	24,550	118,455
Net (decrease) increase in cash and cash equivalents	(105,515)	97,613
Cash and cash equivalents at beginning of period	125,806	28,193
Cash and cash equivalents at end of period	20,291	125,806
Supplemental disclosure
Cash paid for amounts included in the measurement of lease liabilities	686	666
Supplemental non-cash investing and financing activities
Unpaid financing costs	$ 0	$ 464

Organization and Description of

Organization and Description of Business	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	1. Organization and Description of Business CymaBay Therapeutics, Inc. (the Company or CymaBay) is a clinical-stage biopharmaceutical company focused on developing innovative therapies for patients with liver and other chronic diseases with high unmet medical need. The Company’s lead clinical development candidate is seladelpar. Seladelpar has been primarily under development for the treatment primary biliary cholangitis (PBC), a rare liver disease. The Company was incorporated in Delaware in October 1988 as Transtech Corporation. The Company’s headquarters and operations are located in Newark, California and it operates in segment. Liquidity The Company has incurred net operating losses and negative cash flows from operations since its inception. During the year ended December 31, 2022, the Company incurred a net loss of $106.0 million and used $84.1 million of cash in operations. At December 31, 2022, the Company had an accumulated deficit of $872.9 million. Historically, the Company has incurred substantial research and development expenses in the course of studying its product candidates in clinical trials. To date, none of the Company’s product candidates have been approved for marketing and sale, and the Company has not recorded any revenue from product sales. Generally, the Company’s ability to achieve profitability is dependent on its ability to successfully develop, acquire or in-license During and subsequent to the year ended December 31, 2022, the Company completed certain transactions as follows: • In January 2022, the Company received the third installment of million of the Company’s Development Financing Agreement (the Financing Agreement) with ABW Cyclops SPV LP, an affiliate of Abingworth LLP (Abingworth), pursuant to which Abingworth committed to provide million in funding in equal quarterly installments. For further details, refer to Note 6—Development Financing Agreement. • On January 6, 2023, the Company entered into a Collaboration and License Agreement with Kaken Pharmaceutical Co., Ltd (Kaken). Pursuant to the agreement, the Company granted Kaken an exclusive license to commercialize seladelpar for the treatment of PBC in Japan and received an upfront cash payment of million. For further details, refer to Note 13—Subsequent Events. • On January 23, 2023, the Company sold 11,821,428 shares of common stock at $7.00 per share and a pre-funded warrant to purchas per share in a public equity offering, for total net proceeds of million, after deducting underwriting and other offering expenses. For further details, refer to Note 13—Subsequent Events. As of December 31, 2022, the Company had cash, cash equivalents and marketable securities totaling $ million. As the Company continues to advance its clinical studies of seladelpar, the Company believes its existing funds, together with the $ million upfront payment received from Kaken in January 2023 pursuant to the Collaboration and License Agreement and the $ million in net proceeds raised in connection with the January 2023 public equity offering, are sufficient to fund the Company’s current operating plan for at least twelve months from the issuance date of its financial statements. The Company has historically financing affected.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Presentation and Use of Estimates The accompanying consolidated financial statements are comprised of the accounts of CymaBay and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The Company has no unconsolidated subsidiaries or investments accounted for under the equity method. These consolidated statements have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP), which requires management to make informed estimates and assumptions that impact the amounts and disclosures reported in the consolidated financial statements and accompanying notes. Accounting estimates and assumptions are inherently uncertain. Management bases its estimates on historical experience and on assumptions believed to be reasonable under the circumstances. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. Actual results could differ materially from those estimates and assumptions. These estimates form the basis for making judgments about the carrying values of assets and liabilities when these values are not readily apparent from other sources. Estimates are assessed each reporting period and updated to reflect current information. Fair Value of Financial Instruments The Company’s financial instruments during the periods reported consist of cash, cash equivalents, marketable securities, accounts payable, certain accrued liabilities, and the development financing liability. 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 at the measurement date. Assets and liabilities that are measured at fair value are reported using a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs and is as follows: Level 1—Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2—Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly. Level 3—Inputs that are significant to the fair value measurement and are unobservable (i.e. supported by little market activity), which requires the reporting entity to develop its own valuation techniques and assumptions. The carrying amounts of cash equivalents approximate their related fair value due to the short-term nature of these instruments. Cash equivalents are classified as level 1 under the fair value hierarchy. The following tables present the Company’s financial assets that are measured at fair value on a recurring basis using the above input categories (in thousands): As of December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 9,770 $ — $ — $ 9,770 Total cash equivalents 9,770 — — 9,770 Marketable securities: U.S. and foreign commercial paper — 46,121 — 46,121 U.S. and foreign corporate debt securities — 24,807 — 24,807 Supranational debt securities — 12,890 — 12,890 U.S. agency securities — 7,759 — 7,759 U.S. treasury securities — 23,617 — 23,617 Total marketable securities — 115,194 — 115,194 Total assets measured at fair value $ 9,770 $ 115,194 $ — $ 124,964 As of December 31, 2021 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 85,638 $ — $ — $ 85,638 Total cash equivalents 85,638 — — 85,638 Marketable securities: U.S. and foreign commercial paper — 28,760 — 28,760 U.S. and foreign corporate debt securities — 23,535 — 23,535 Asset-backed securities — 8,522 — 8,522 U.S. treasury securities — 7,979 — 7,979 Total marketable securities — 68,796 — 68,796 Total assets measured at fair value $ 85,638 $ 68,796 $ — $ 154,434 The Company estimates the fair value of its money market funds, corporate debt, asset-backed securities, commercial paper, U.S. treasury and agency securities, and supranational debt securities by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, issuer credit spreads; benchmark securities; prepayment/default projections based on historical data; and other observable inputs. The fair value of the Company’s development financing liability is $79.5 million. The development financing liability is classified as level 3 under the fair value hierarchy as its valuation is based on a discounted cash flow model that uses unobservable inputs such as the estimated timing of regulatory approval, attainment of certain sales milestones and the discount rate. Cash, Cash Equivalents, and Marketable Securities The Company considers all highly liquid investments with an original maturity of 90 days or less at the time of purchase to be cash equivalents. Cash and cash equivalents consist of deposits with commercial banks in checking, interest-bearing, and money market funds. The Company invests excess cash in marketable securities with high credit ratings. These securities consist primarily of corporate debt, commercial paper, asset-backed securities, U.S. treasury, U.S. agency securities and supranational debt securities and are classified as “available-for-sale.” Realized gains and losses from the sale of marketable securities, if any, are calculated using the specific-identification method. Realized gains and losses and declines in value judged to be other-than-temporary are included in interest income or expense in the consolidated statements of operations and comprehensive loss. Unrealized holding gains and losses are reported in accumulated other comprehensive loss in the consolidated balance sheets. To date, the Company has not recorded any impairment charges on its marketable securities related to other-than-temporary declines in market value. In determining whether a decline in market value is other-than-temporary, various factors are considered, including the cause, duration of time and severity of the impairment, any adverse changes in the investees’ financial condition, and the Company’s intent and ability to hold the security for a period of time sufficient to allow for an anticipated recovery in market value. Concentration of Risk Cash, cash equivalents, and market The Company maintains deposits in excess of FDIC insured deposit limits with its financial institutions. Certain materials and key components that the Company utilizes in its operations are obtained through single suppliers. Since the suppliers of key components and materials must be named in an NDA filed with the FDA for a product, significant delays can occur if the qualification of a new supplier is required. If delivery of material from the Company’s suppliers were interrupted for any reason, the Company may be unable to supply any of its product candidates for clinical trials. Property and Equipment Property three non-cancelable Long-Lived Assets The Company reviews the carrying value long-lived assets, including right-of-use assets may not be fully recoverable. If a change in circumstance occurs, the Company performs a test of recoverability by comparing the carrying value of the asset or asset group to its undiscounted expected future cash flows. If cash flows cannot be separately and independently identified for a single asset, the Company will determine whether impairment has occurred for the group of assets for which the Company can identify the projected cash flows. If the carrying values are in excess of undiscounted expected future cash flows, the Company measures any impairment by comparing the fair value of the asset or asset group to its carrying value. There were no indicators of impairment of long-lived assets for any periods presented Leases The Company has one lease, a non-cancelable right-of-use right-of-use The operating lease right-of-use non-lease non-lease Research and Development Expenses Research and development expenses consist of costs incurred in identifying, developing, and testing product candidates. These expenses consist primarily of costs for research and development personnel, including related stock-based compensation; contract research organizations (CRO) and other third parties that assist in managing, monitoring, and analyzing clinical trials; investigator and site fees; laboratory services; consultants; contract manufacturing services; non-clinical The Company records expenses related to clinical studies and manufacturing development activities based on its estimates of the services received and efforts expended pursuant to contracts with multiple CROs and manufacturing vendors that conduct and manage these activities on its behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract, and may result in uneven payment flows. There may be instances in which payments made to the Company’s vendors will exceed the level of services provided and result in a prepayment. Payments under some of these contracts depend on factors such as the successful enrollment of subjects and the completion of clinical trial milestones. In expensing service fees, the Company estimates the time period over which services will be performed, enrollment of subjects, number of sites activated and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the Company’s estimate, the Company will adjust the accrued or prepaid expense balance accordingly. In 2022 and 2021, there have been no material differences from the Company’s estimates to the amounts actually incurred. Development Financing Agreement The Company accounts for the Development Financing Agreement with Abingworth as a debt instrument. Accordingly, the Company has recorded payments received under the Financing Agreement as part of a development financing liability in the Company’s consolidated balance sheet. The liability is recorded at amortized cost and accreted to the contractual success fee amounts based on the estimated timing of regulatory approval and attainment of certain sales milestones using an imputed interest rate. Certain transaction fees incurred specifically to complete the Financing Agreement were capitalized and recorded as a reduction to the carrying amount of the development financing liability and are being amortized to interest expense using the effective interest rate method. There are several factors that could affect the estimated timing of regulatory approval and attainment of sales milestones, some of which are not entirely within the Company’s control. Therefore, the Company periodically reassesses the estimated timing of regulatory approval and attainment of sales milestones, and the expected contractual success fee payments due therefrom. If the timing and/or amount of such expected payments is materially different than original estimates, the Company will prospectively adjust the accretion of the development financing liability and the imputed interest rate. The Company identified certain contingent repayment features in the Financing Agreement that are required to be bifurcated from the debt host instrument as embedded derivative liabilities; however, the Company determined the fair value of these features, both individually and in the aggregate, was immaterial at inception and as of December 31, 2022. The fair value of these features will be assessed at each reporting date and will be marked to market, if material. To determine the amount to record for the embedded derivative liabilities, the Company must assess the probability of occurrence of various potential future Pre-funded Pursuant to the Company’s public equity offering co mpleted in pre-funded pre-funded pre-funded pre-funded paid-in Note 9—Stockholders’ Equity information. Stock-Based Compensation Stock-based compensation is measured at fair value on the grant date of the award. Compensation cost is recognized as expense on a straight-line basis over the vesting period for options with service conditions and forfeitures are accounted for as they occur. The Company uses the Black-Scholes option-pricing model to determine the fair value of stock option awards. The determination of fair value for stock-based awards using an option-pricing model requires management to make certain assumptions regarding subjective input variables such as expected term, dividends, volatility and risk-free rate. If actual results are not consistent with the Company’s assumptions used in making these estimates, the Company may be required to increase or decrease compensation expense, which could be material to the Company’s results of operations. Income Taxes The Company The accounting guidance for uncertainty in income taxes prescribes a recognition threshold and measurement attribute criteria for the financial recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination based on the technical merits of the position. The Company is required to file federal and state income tax returns in the United States. The preparation of these income tax returns requires the Company to interpret the applicable tax laws and regulations in effect that could affect the amount of tax paid to these jurisdictions. The Company records interest related to income tax reserves, if any, as interest expense, and any penalties would be recorded as other expense in the consolidated statements of operations and comprehensive loss. Comprehensive Loss Comprehensive loss includes net loss and net unrealized gains and losses on marketable securities, which are presented in a single continuous statement. Other comprehensive (loss) gain is also disclosed in the consolidated balance sheets and statements of stockholders’ equity in accumulated other comprehensive income (loss), and is stated net of related tax effects, if any. Net Loss Per Common Share Basic net loss per share of common stock is based on the weighted average number of shares of common stock and common stock equivalents outstanding during the period. The weighted-average common shares outstanding as of December 31, 2022 and 2021 includes pre-funded warrants to purchase up to 3,125,000 shares of common stock that were issued in connection with the November 2021 public offering, as discussed in Note 9—Stockholders’ Equity net loss per share of common stock is calculated as the weighted average number of shares of common stock outstanding adjusted to include the assumed exercises of stock options, if dilutive. In all periods presented, the Company’s outstanding stock options and incentive awards were excluded from the calculation of net loss per share because the effect would be antidilutive. The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts): Year Ended December 31, 2022 2021 Numerator: Net loss $ (106,001 ) $ (89,998 ) Denominator: Weighted average number of: Common stock shares outstanding 84,679,063 70,712,865 Pre-funded warrants outstanding 3,125,000 342,466 Total 87,804,063 71,055,331 Net loss per share $ (1.21 ) $ (1.27 ) The following table shows the total outstanding securities considered anti-dilutive and therefore excluded from the computation of diluted net loss per share (in thousands): Year Ended 2022 2021 Common stock options 13,930 10,791 Incentive awards 101 101 Total 14,031 10,892 Recently Issued Accounting Pronouncements ASU 2016-13 In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments available-for-sale No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815) and Leases (Topic 842)

Marketable Securities

Marketable Securities	12 Months Ended
	Dec. 31, 2022
Cash and Cash Equivalents [Abstract]
Marketable Securities	3. Marketable Securities Marketable available-for-sale Amortized Unrealized Unrealized Estimated As of December 31, 2022: Cash equivalents: Money market funds $ 9,770 $ — $ — $ 9,770 Total cash equivalents 9,770 — — 9,770 Current marketable securities: U.S. and foreign commercial paper 46,121 — — 46,121 U.S. and foreign corporate debt securities 24,964 — (157 ) 24,807 Supranational debt securities 12,946 — (56 ) 12,890 U.S. agency securities 7,782 16 (39 ) 7,759 U.S. treasury securities 23,707 2 (92 ) 23,617 Total current marketable securities 115,520 18 (344 ) 115,194 Total marketable securities $ 125,290 $ 18 $ (344 ) $ 124,964 Amortized Gross Gross Estimated As of December 31, 2021: Cash equivalents: Money market funds $ 85,638 $ — $ — $ 85,638 Total cash equivalents 85,638 — — 85,638 Current marketable securities: U.S. and foreign commercial paper 28,760 — — 28,760 U.S. and foreign corporate debt securities 15,476 — (8 ) 15,468 Asset-backed securities 8,524 1 (3 ) 8,522 U.S. treasury securities 7,982 — (3 ) 7,979 Total current marketable securities 60,742 1 (14 ) 60,729 Non-current U.S. corporate debt securities 8,067 3 (2 ) 8,068 Total marketable securities $ 154,447 $ 4 $ (16 ) $ 154,435 The Company’s commercial paper and corporate debt securities consist of U.S. and foreign securities from issuers in various sectors, including finance and industry and have similar credit quality and risk characteristics. The Company’s asset-backed securities are collateralized by credit card receivables and have investment-grade ratings. The Company’s government securities are issued by the U.S. treasury and certain U.S. government-backed agencies. Supranational debt securities consist of securities issued with funding from various national governments. There were no realized gains and losses for the years ended December 31, 2022 and 2021. None of our investments have been in a continuous unrealized loss position for more than 12 months as of December 31, 2022 and 2021. The Company may sell certain of its marketable securities prior to their stated maturities for reasons including, but not limited to, managing liquidity, credit risk, duration and asset allocation. The following table shows the fair value of the Company’s marketable securities, by contractual maturity, as of December 31, 2022 (in thousands): Due less than 1 year $ 115,194 Due between 1 and 2 years — Total fair value $ 115,194

Certain Balance Sheet Items

Certain Balance Sheet Items	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Certain Balance Sheet Items	4. Certain Balance Sheet Items Property and equipment are recorded at cost and consist of the following (in thousands): December 31, December 31, Leasehold improvements $ 2,429 $ 2,429 Office and computer equipment 290 290 Purchased software 44 44 Furniture and fixtures 687 539 Total 3,450 3,302 Less: Accumulated depreciation and amortization (2,749 ) (2,124 ) Property and equipment, net $ 701 $ 1,178 Depreciation and amortization expense for the years ended December 31, 2022 and 2021 was approximately $0.7 million and $0.7 million, respectively, and was recorded straight-line in both research and development expense and general and administrative expense in the consolidated statements of operations and comprehensive loss. All the Company’s property and equipment is located in the U.S. Other accrued liabilities consist of the following (in thousands): December 31, December 31, Accrued compensation $ 5,779 $ 3,986 Accrued professional fees and other 1,372 1,333 Current portion of operating lease liability 664 567 Total other accrued liabilities $ 7,815 $ 5,886

In-License Agreement

In-License Agreement	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
In-License Agreement	5. In-License Janssen Pharmaceutica NV In June 2006, the Company entered into an exclusive worldwide, royalty-bearing license to seladelpar and certain other PPAR d d d d d d December 2021.

Development Financing Agreement

Development Financing Agreement	12 Months Ended
	Dec. 31, 2022
Debt Disclosure [Abstract]
Development Financing Agreement	6. Development Financing Agreement On July 30, 2021 (the Effective Date), the Company entered into a Development Financing Agreement (the Financing Agreement) with Abingworth to provide funding to the Company to support its development of seladelpar for the treatment of primary biliary cholangitis (PBC). The Financing Agreement provided the Company up to million in base funding January 2022. The use of proceeds from the funding is limited to PBC “Development Program” costs incurred or paid as defined in the Financing Agreement. In return, the Company will pay to Abingworth: (1) contingent upon the first to occur of regulatory approval of seladelpar for the treatment of PBC in the U.S., U.K., Germany, Spain, Italy or France (Regulatory Approval), fixed success payments equal to 2.0x of the funding provided, consisting of $10 million payable in 90 days after the Regulatory Approval and thereafter, payments due on the first six anniversaries of the Regulatory Approval in the amounts of $15.0 million, $22.5 million, $22.5 million, $25.0 million, $27.5 million and $27.5 million, respectively and (2) variable success payments equal to 1.1x of the funding provided, consisting of sales milestone payments of (x) $17.5 million and $27.5 million, respectively upon first reaching certain cumulative U.S. product sales thresholds, and (y) $37.5 million upon first reaching a specified U.S. product sales run rate. Promptly following receipt of Regulatory Approval, the Company is required to execute a note agreement and deliver a promissory note to Abingworth within two business days to convert the fixed and variable success payments into a note payable. At the time that Abingworth receives, collectively, an aggregate of 3.1x of the funding provided (approximately $232.5 million), the Company’s payment obligations under the Financing Agreement will be fully satisfied. The Company has the option to satisfy its payment obligations to Abingworth upon Regulatory Approval, or a change of control of the Company, by paying an amount equal to the remaining payments payable to Abingworth subject to a mid-single-digit Pursuant to the Financing Agreement, the Company granted Abingworth a security interest in all its assets (other than intellectual property not related to seladelpar), provided that the Company is permitted to incur certain indebtedness. The security interest will terminate when the Company has paid Abingworth 2.0x The Financing Agreement provides for negative, affirmative and additional covenants, which the Company must comply with for the duration of the Financing Agreement term. As of December 31, 2022, the Company was in compliance with all covenants stipulated in the Financing Agreement. In certain instances, upon the termination of the Financing Agreement, the Company will be obligated to pay Abingworth a multiple of the amounts paid to the Company under the Financing Agreement, including specifically: (i) 310% of such amounts in the event that Abingworth terminates the Financing Agreement due to (x) a Fundamental Breach, as defined in the Financing Agreement, (y) the bankruptcy of the Company, or (z) a safety concern resulting from gross negligence on the part of the Company or due to a safety concern that was material on the Effective Date and the material data showing such safety concern was not publicly known, disclosed to Abingworth, or in the diligence room made available to Abingworth, (ii) 200% of such amounts in the event the Financing Agreement is terminated due to (x) Material Breach, as defined in the Financing Agreement, by the Company or (y) the security interests of Abingworth being invalidated or terminated other than as set forth in the Financing Agreement, and (iii) In addition, if, following certain terminations, the Company continues to develop seladelpar for the treatment of PBC and obtains regulatory approval, it will make the payments to Abingworth as if the Financing Agreement had not been terminated, less any payments made upon termination. The Company shall not be obligated to make any payments to Abingworth under certain instances of technical or regulatory failure of the PBC development program as defined in the Financing Agreement. As part of the arrangement, an executive review committee was established between the Company and Abingworth to discuss the Company’s development of seladelpar. The Company evaluated the Financing Agreement and determined it to be a research and development funding arrangement with the characteristics of a debt instrument as the transfer of financial risk to Abingworth was not considered substantive and genuine. Accordingly, the Company has recorded payments received under the Financing Agreement as part of a development financing liability in its consolidated balance sheets. The Company accounts for the overall development financing liability at amortized cost based on the estimated timing of regulatory approval and attainment of certain sales milestones and the contractual success fee payments expected to be due therefrom, as discounted using an imputed interest rate. The development financing liability is being accreted as interest expense to its expected future repayment amount over the expected life of the agreement using the effective interest rate method. Certain legal and financial advisory fees incurred specifically to complete the Financing Agreement were capitalized and recorded as a reduction to the carrying amount of the development financing liability and are also being amortized to interest expense using the effective interest method. There are several factors that could affect the estimated timing of regulatory approval and attainment of sales milestones, some of which are not entirely within the Company’s control. Therefore, the Company periodically reassesses the estimated timing of regulatory approval and attainment of sales milestones, and the expected contractual success fee payments due therefrom. If the timing and/or amount of such expected payments is materially different than original estimates, the Company will prospectively adjust the accretion of the development financing liability and the imputed interest rate. The Company identified certain contingent repayment features in the agreement that are required to be bifurcated from the debt host instrument as embedded derivative liabilities; however, the fair value of these features was immaterial at the Effective Date and as of December 31, 2022 and 2021. The fair value of the embedded derivative liabilities will be assessed at subsequent reporting dates if material. The following table sets forth a summary of the changes in the carrying value of the Company’s development financing liability (in thousands): Balance at December 31, 2021 $ 50,320 Cash received 25,000 Accretion of development financing liability 14,907 Balance at December 31, 2022 $ 90,227 As of December 31, 2022, the development financing liability was classified as a long-term liability as the Company expects the related repayments to take place between 2024 and 2030 for purposes of the model used to calc of

Leases

Leases	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Leases	7. Leases The Company has one operating lease pertaining to 17,698 square feet of corporate office space in Newark, California pursuant to a lease agreement that commenced January 16, 2014 and was amended on April 16, 2018. At December 31, 2022 and December 31, 2021, the Company’s lease portfolio had a weighted average remaining term of 1.1 years, and 2.1 years, respectively, with an option to extend for an additional 5 years. The lease requires monthly lease payments that are subject to annual increases throughout the lease term. The optional period has not been considered in the determination of the right-of-use The Company cannot determine the implicit rate in its lease, and therefore the Company uses its incremental borrowing rate of 12.6% as the discount rate For the years ended December 31, 2022 and 2021, the Company incurred $0.7 million and $0.6 million, respectively, of lease costs included in operating expenses in the consolidated statements of operations and comprehensive loss in relation to its operating lease, a portion of which was variable rent expense and not included within the measurement of the Company’s operating ROU assets and lease liabilities. The variable rent expense consists primarily of the Company’s proportionate share of operating expenses, property taxes, and insurance and is classified as lease expense due to the Company’s election to not separate lease and non-lease right-of-use As of December 31, 2022, the maturities of the Company’s operating lease liabilities were as follows (in thousands): Year ending December 31, 2023 $ 707 2024 30 Total undiscounted future minimum lease payments 737 Less imputed interest 43 Total operating lease liability 694 Less: current portion of operating lease liability 664 Long-term portion of lease liability $ 30

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies Indemnification In the normal course of business, the Company enters into contracts and agreements that contain a variety of representations and warranties and provide for general indemnification, including indemnification associated with product liability or infringement of intellectual property rights. The Company’s exposure under these agreements is unknown because it involves future claims that may be made against the Company that may be, but have not yet been, made. To date, the Company has not paid any claims or been required to defend any action related to these indemnification obligations, and no amounts have been accrued in the accompanying consolidated balance sheets related to these indemnification obligations. The Company has agreed to indemnify its officers and directors for losses and costs incurred in connection with certain events or occurrences, including advancing money to cover certain costs, subject to certain limitations. The maximum potential amount of future payments the Company could be required to make under this indemnification is unlimited; however, the Company maintains insurance policies that may limit its exposure and may enable it to recover a portion of any future amounts paid. Assuming the Genfit Litigation On January 15, 2021, Genfit S.A. (Genfit) filed a complaint against the Company in the U.S. District Court for the Northern District of California, alleging misappropriation of trade secrets and related causes of action based on the Company’s receipt of a Genfit protocol synopsis for Genfit’s Phase 3 clinical trial of its drug candidate elafibranor in patients with primary biliary cholangitis. An Amended Complaint was filed on April 16, 2021 with substantially the same allegations. Genfit was ing What remained in the complaint was an alleged misappropriation of the protocol synopsis as a whole. The Company filed its Answer to what remained of the Second Amended Complaint on February 4, 2022

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Stockholders' Equity	9 Preferred and Common Stock Authorized The Company is authorized to issue 10,000,000 shares of preferred stock as of December 31, 2022 and 2021, and 200,000,000 shares of common stock as of December 31, 2022 and 2021. Common Stock Reserved for Future Issuance As of December 31, 2022 and 2021, the Company had reserved shares of common stock for future issuances as follows: December 31, 2022 2021 Pre-funded 3,125,000 3,125,000 Equity award plans: Options and incentive awards outstanding, all equity plans 14,031,377 10,892,613 Equity awards available for future grant - 2013 Plan 2,680,621 1,588,613 Equity awards available for future grant - 2020 Plan — — Total shares of common stock reserved for future issuance 19,836,998 15,606,226 Sale of Common Stock and Pre-funded In November 2021, pursuant to a shelf registration statement on Form S-3, pre-funded pre-funded shares of common stock were issued at a price of per share, have an exercise price of per share, were fully exercisable upon issuance, and have no expiration date. The Company determined that the pre-funded pre-funded paid-in pre-funded On January 23, 2023, the Company issue d 11,821,428 shares of its common stock at $7.00 per share in an underwritten public offering. The Company also issued a pre-funded f 2,142,857 shares of common stock at a purchase price o f $6.9999 per share and has an exercise price of per share. Refer to Note 13—Subsequent Events

Stock Plans and Stock-Based Com

Stock Plans and Stock-Based Compensation	12 Months Ended
	Dec. 31, 2022
Share-based Payment Arrangement [Abstract]
Stock Plans and Stock-Based Compensation	10. Stock Plans and Stock-Based Compensation Stock Plans In September 2013, the Company’s stockholders approved the 2013 Equity Incentive Plan (the 2013 Plan), under which shares of common stock are reserved for the granting of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance stock awards, performance cash awards and other stock awards by the Company. These awards may be granted to employees, members of the Board of Directors, and consultants. The 2013 Plan has a term of ten years and replaced 10% stockholders have a maximum term of five years and require an exercise price equal to at least 110 % of the fair value on the date of grant. The exercise price of all options granted to date has been at least equal to the fair value of common stock on the date of grant. Stock option exercises are settled with shares reserved under the 2013 Plan. The share reserve under the 2013 Plan will automatically increase on January 1 st f each year, for a period of not more of the total number of shares of capital stock outstanding on December 31 st st In October 2020, the Company’s board of directors approved the 2020 New Hire Plan (the 2020 Plan), under which shares of common stock are reserved for the granting of nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock unit awards, performance stock awards, performance cash awards and other stock awards by the Company as an inducement to prospective new hire employees of the Company. The 2020 Plan has a term of ten years. The 2020 Plan permits the Company to (i) grant nonqualified options to new hire employees at not less than 85 % of fair value; (ii) award stock bonuses; and (iii) grant rights to acquire restricted stock at not less than 85% of fair value. Options generally vest over a four-year period and have a term of ten years. The share reserve under the 2020 Plan may be increased at the discretion of and approval by the board of directors. Stock Plan Activity As of December 31, 2022, there were 2,680,621 and no shares available for grant under the 2013 and 2020 Plans, respectively. On January 1, 202 3 The following table summarizes activity in the Company’s stock option grants: Shares Weighted- Weighted- Aggregate Outstanding as of December 31, 2021 10,791,431 $ 6.01 Options granted 3,692,868 2.94 Options exercised (3,124 ) 2.94 Options forfeited (403,210 ) 4.08 Options expired (147,770 ) 5.24 Outstanding as of December 31, 2022 13,930,195 $ 5.26 6.96 $ 26,089 Vested and expected to vest as of December 31, 2022 13,930,195 $ 5.26 6.96 $ 26,089 Exercisable as of December 31, 2022 9,004,373 $ 6.00 6.08 $ 13,858 The total The total fair value of options vested was $0.6 million and $0.7 million for the years ended December 31, 2022 and 2021, respectively. As of December 31, 2022, unamortized stock-based compensation expense of $14.7 million is expected to be recognized over a weighted average period of 2.4 years. Incentive Awards In December 2013, January 2014, and April 2014, as permitted by the 2013 Plan, the Company issued certain incentive awards to directors, employees and a consultant which are subject to 252,752 shares of the Company’s common stock and are exercisable at a weighted average price of $5.21 per share when vested. The Company may determine at its option whether to settle exercised awards in shares of common stock or in cash. The incentive awards were fully vested as of December 31, 2022 and 2021 and have a term of 10 years. Incentive awards outstanding totaled 101,182 as of December 31, 2022 and 2021. Stock-Based Compensation Expense Stock-based compensation expense is included in the consolidated statements of operations and comprehensive loss and is as follows (in thousands): Year Ended December 31, 2022 2021 Research and development $ 4,274 $ 4,470 General and administrative 5,243 5,526 Total stock-based compensation expense $ 9,517 $ 9,996 Valuation Assumptions The following table presents the weighted-average assumptions the Company used in the Black-Scholes option-pricing model to derive the grant date fair values of stock options granted in each of the years presented Year Ended December 31, 2022 2021 Expected term (years) 6.0 6.1 Expected volatility 101 % 104 % Risk-free interest rate 1.8 % 0.9 % Expected dividend yield — — Weighted-average grant date fair value per share $ 2.33 $ 3.91 Expected Term The Company does not believe it can currently place reliance on its historical exercise and post-vesting termination activity to provide accurate data for estimating the expected term due to the lack of sufficient prior exercise data available. Therefore, for stock option grants made during the years ended December 31, 2022 and 2021, the Company has elected to use the simplified method for estimating the expected term, which is an average of the contractual term of the options and its ordinary vesting period. The Company will reevaluate this methodology at a point in time when sufficient exercise data becomes available. The expected term represents the period of time that options are expected to be outstanding. Expected Volatility The Company estimates expected volatility by measuring the historical volatility of its common stock price over a historical period commensurate with the expected term of the related award. Risk-Free Interest Rate The risk-free interest rate assumption was based on U.S. treasury instruments with constant maturities whose term was consistent with the expected term of stock options granted by the Company. Expected Dividend Yield The Company has never declared or paid cash dividends and does not plan to pay cash dividends in

401(k) Plan

401(k) Plan	12 Months Ended
	Dec. 31, 2022
Postemployment Benefits [Abstract]
401(k) Plan	11. 401(k) Plan The Company provides a qualified 401(k) savings plan for its employees. All employees are eligible to participate, provided they meet the requirements of the plan. As is permitted under the plan, the Company has elected to match employee contributions up to $750 and accordingly matching contributions totaling an insignificant amount were made in the years ended December 31, 2022 and 2021.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes No provision for U.S. income taxes exists due to tax losses incurred in all periods presented. All losses incurred were U.S. based. Significant components of the Company’s deferred December 31, 2022 2021 Deferred tax assets: Federal and state net operating loss carryforwards $ 87,681 $ 129,898 State and federal research and development tax credit carryforwards 32,016 31,951 Intangibles and capitalized research and development 16,912 5,670 Stock-based compensation 6,624 5,329 Other 1,574 1,222 Total deferred tax assets 144,807 174,070 Deferred tax liabilities: Depreciation and amortization (79 ) (158 ) Other (36 ) (53 ) Total deferred tax liabilities (115 ) (211 ) Valuation allowance (144,692 ) (173,859 ) Net deferred tax assets $ — $ — Realization of the net deferred tax assets is dependent upon future taxable income, if any, the amount and timing of which is uncertain. Based on the weight of available positive and negative objective evidence, management believes it more likely than not that the Company’s deferred tax assets are not realizable. Accordingly, the net deferred tax assets have been fully offset by a valuation allowance. The valuation allowance decreased by $ million primarily due primarily to a $ 38.4 million write-off of tax attributes pursuant to certain Section 382 limitations and to a lesser extent the utilization of net operating losses during the year ended December 31, 2022, These valuation allowance reductions were offset in part by valuation allowance increases to cover additions to the Company’s capitalized research and development and other deferred tax assets during the year ended December 31, 2022. The valuation allowance increased by $ 14.7 million primarily due to an increase in the Company’s taxable loss during the year ended December 31, 2021. The following is a reconciliation of the expected statutory federal income tax provision to the actual income tax provision (in thousands): December 31, 2022 2021 Income tax benefit at federal statutory tax rate $ (22,260 ) $ (18,900 ) Change in valuation allowance (29,165 ) 14,739 Impairment of tax attributes 38,398 — Research credits (2,640 ) (2,802 ) Cancelled options 49 141 Development financing liability 12,301 6,654 Permanent differences 511 429 State income taxes, net of federal benefit 2,806 (267 ) Other, net — 6 Income tax (benefit) expense $ — $ — Pursuant to Internal Revenue Code (IRC) Sections 382 and 383 and similar state laws, use of the Company’s U.S. federal and state net operating loss and research and credit carryforwards may be limited in the event of a cumulative change in ownership of more than 50% within a three period. In 2022, the Company completed an ownership change analysis and determined that its net operating losses and research and development credits were subject to limitations due to historical changes in ownership that occurred through December 31, 2022. Accordingly, the net operating loss carryforwards reflected in the deferred tax assets at December 31, 2022 have been reduced to reflect Section 382 limitations resulting from these changes. As the Company is expected to incur additional losses in the future, any future ownership changes that might occur could further restrict the Company’s ability to utilize its net operating loss and research and development carryforwards. As of December 31, 2022, the Company had federal net operating loss carryforwards of $ million and state net operating loss carryforwards of $ million to offset future taxable income, if any. In addition, the Company had federal research and development tax credit carryforwards of $ million, federal orphan drug tax credit carryforwards of $ million, and state research and development tax credit carryforwards of $ million. If not utilized, the federal net operating losses for the years beginning before January 1, 2018 of $ million will expire beginning in through , and the federal net operating losses for the tax years beginning after January 1, 2018 of $ million will be carried forward indefinitely (subject to certain utilization limitations). Balances as of December 31, 2020 $ 7,205 Increases related to prior year tax positions 9 Increases related to 2021 tax positions 783 Balances as of December 31, 2021 7,997 Decreases related to prior year tax positions (1,223 ) Increases related to 2022 tax positions 730 Balances as of December 31, 2022 $ 7,504 The unrecognized tax benefits, if recognized, would not have an impact on the Company’s effective tax rate assuming the Company continues to maintain a full valuation allowance position. Based on prior year’s operations and experience, the Company does expect a significant change to its unrecognized tax benefits over the next twelve months. The unrecognized tax benefits may increase or change in the future for unexpected or unusual items for items that may arise in the ordinary course of business. The Company’s major income tax filing jurisdictions are the U.S. federal and California state and is not currently under examination by federal, state, or local taxing authorities for any open tax years. Due to net operating loss carryforwards returns. Interest and penalties for the years ended December 31, 2022 and 2021 were not material. In August 2022, the Inflation Reduction Act of 2022 (IRA) was signed into law. The IRA provides several tax incentives, including the expanded Internal Revenue Code (IRC) Section 179D deduction, increased ability to leverage the R&D credit to offset payroll taxes for eligible start-up billion for the past three tax periods. The IRA did not have a material impact on the Company’s consolidated financial statements; however, the Company continues to examine the impacts the above-mentioned tax legislations may have on its business, results of operations, financial condition and liquidity.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2022
Subsequent Events [Abstract]
Subsequent Events	13. Subsequent Events Collaboration and License Agreement with Kaken Pharmaceutical Co., Ltd. In January 2023, the Company entered into a Collaboration and License Agreement (the License Agreement) with Kaken Pharmaceutical Co., Ltd. (Kaken). Pursuant to the License Agreement, the Company granted Kaken an exclusive license to commercialize seladelpar (the Licensed Product) for the treatment of PBC in Japan. Kaken will bear the cost of, and be responsible for, conducting clinical studies and other developmental activities, preparing and filing applications for regulatory approval and commercializing seladelpar in Japan. The Company is generally obligated to supply seladelpar to Kaken for use in Japan, at a supply price per unit as defined in the agreement. In consideration of the license and other rights granted by the Company, Kaken made an upfront cash payment to the Company of $ million in January 2023 and is obligated to make potential milestone payments to the Company totaling up to ¥ billion (approximately $ million using exchange rates in effect at the contract inception date) contingent upon Kaken’s achievement of certain regulatory and sales milestones as defined in the agreement. Sale of Common Stock and Pre-funded On January 23, 2023, pursuant to a shelf registration statement on Form S-3, sold shares per share in an underwritten public equity and a pre-funded shares of common stock at a purchase price of per share, which represents the per share public offering price for the common stock less the per share exercise price of the pre-funded warrant. The Company received net proceeds of million from this public equity offering after deducting underwriting and other offering expenses.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation and Use of Estimates	Basis of Presentation and Use of Estimates The accompanying consolidated financial statements are comprised of the accounts of CymaBay and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. The Company has no unconsolidated subsidiaries or investments accounted for under the equity method. These consolidated statements have been prepared in accordance with accounting principles generally accepted in the United States of America (U.S. GAAP), which requires management to make informed estimates and assumptions that impact the amounts and disclosures reported in the consolidated financial statements and accompanying notes. Accounting estimates and assumptions are inherently uncertain. Management bases its estimates on historical experience and on assumptions believed to be reasonable under the circumstances. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. Actual results could differ materially from those estimates and assumptions. These estimates form the basis for making judgments about the carrying values of assets and liabilities when these values are not readily apparent from other sources. Estimates are assessed each reporting period and updated to reflect current information.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company’s financial instruments during the periods reported consist of cash, cash equivalents, marketable securities, accounts payable, certain accrued liabilities, and the development financing liability. 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 at the measurement date. Assets and liabilities that are measured at fair value are reported using a three-level fair value hierarchy that prioritizes the inputs used to measure fair value. This hierarchy maximizes the use of observable inputs and minimizes the use of unobservable inputs and is as follows: Level 1—Quoted prices in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2—Inputs other than quoted prices in active markets that are observable for the asset or liability, either directly or indirectly. Level 3—Inputs that are significant to the fair value measurement and are unobservable (i.e. supported by little market activity), which requires the reporting entity to develop its own valuation techniques and assumptions. The carrying amounts of cash equivalents approximate their related fair value due to the short-term nature of these instruments. Cash equivalents are classified as level 1 under the fair value hierarchy. The following tables present the Company’s financial assets that are measured at fair value on a recurring basis using the above input categories (in thousands): As of December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 9,770 $ — $ — $ 9,770 Total cash equivalents 9,770 — — 9,770 Marketable securities: U.S. and foreign commercial paper — 46,121 — 46,121 U.S. and foreign corporate debt securities — 24,807 — 24,807 Supranational debt securities — 12,890 — 12,890 U.S. agency securities — 7,759 — 7,759 U.S. treasury securities — 23,617 — 23,617 Total marketable securities — 115,194 — 115,194 Total assets measured at fair value $ 9,770 $ 115,194 $ — $ 124,964 As of December 31, 2021 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 85,638 $ — $ — $ 85,638 Total cash equivalents 85,638 — — 85,638 Marketable securities: U.S. and foreign commercial paper — 28,760 — 28,760 U.S. and foreign corporate debt securities — 23,535 — 23,535 Asset-backed securities — 8,522 — 8,522 U.S. treasury securities — 7,979 — 7,979 Total marketable securities — 68,796 — 68,796 Total assets measured at fair value $ 85,638 $ 68,796 $ — $ 154,434 The Company estimates the fair value of its money market funds, corporate debt, asset-backed securities, commercial paper, U.S. treasury and agency securities, and supranational debt securities by taking into consideration valuations obtained from third-party pricing services. The pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, issuer credit spreads; benchmark securities; prepayment/default projections based on historical data; and other observable inputs. The fair value of the Company’s development financing liability is $79.5 million. The development financing liability is classified as level 3 under the fair value hierarchy as its valuation is based on a discounted cash flow model that uses unobservable inputs such as the estimated timing of regulatory approval, attainment of certain sales milestones and the discount rate.
Cash, Cash Equivalents, and Marketable Securities	Cash, Cash Equivalents, and Marketable Securities The Company considers all highly liquid investments with an original maturity of 90 days or less at the time of purchase to be cash equivalents. Cash and cash equivalents consist of deposits with commercial banks in checking, interest-bearing, and money market funds. The Company invests excess cash in marketable securities with high credit ratings. These securities consist primarily of corporate debt, commercial paper, asset-backed securities, U.S. treasury, U.S. agency securities and supranational debt securities and are classified as “available-for-sale.” Realized gains and losses from the sale of marketable securities, if any, are calculated using the specific-identification method. Realized gains and losses and declines in value judged to be other-than-temporary are included in interest income or expense in the consolidated statements of operations and comprehensive loss. Unrealized holding gains and losses are reported in accumulated other comprehensive loss in the consolidated balance sheets. To date, the Company has not recorded any impairment charges on its marketable securities related to other-than-temporary declines in market value. In determining whether a decline in market value is other-than-temporary, various factors are considered, including the cause, duration of time and severity of the impairment, any adverse changes in the investees’ financial condition, and the Company’s intent and ability to hold the security for a period of time sufficient to allow for an anticipated recovery in market value.
Concentration of Risk	Concentration of Risk Cash, cash equivalents, and market The Company maintains deposits in excess of FDIC insured deposit limits with its financial institutions. Certain materials and key components that the Company utilizes in its operations are obtained through single suppliers. Since the suppliers of key components and materials must be named in an NDA filed with the FDA for a product, significant delays can occur if the qualification of a new supplier is required. If delivery of material from the Company’s suppliers were interrupted for any reason, the Company may be unable to supply any of its product candidates for clinical trials.
Property and Equipment	Property and Equipment Property three non-cancelable
Long-Lived Assets	Long-Lived Assets The Company reviews the carrying value long-lived assets, including right-of-use assets may not be fully recoverable. If a change in circumstance occurs, the Company performs a test of recoverability by comparing the carrying value of the asset or asset group to its undiscounted expected future cash flows. If cash flows cannot be separately and independently identified for a single asset, the Company will determine whether impairment has occurred for the group of assets for which the Company can identify the projected cash flows. If the carrying values are in excess of undiscounted expected future cash flows, the Company measures any impairment by comparing the fair value of the asset or asset group to its carrying value. There were no indicators of impairment of long-lived assets for any periods presented
Leases	Leases The Company has one lease, a non-cancelable right-of-use right-of-use The operating lease right-of-use non-lease non-lease
Research and Development Expenses	Research and Development Expenses Research and development expenses consist of costs incurred in identifying, developing, and testing product candidates. These expenses consist primarily of costs for research and development personnel, including related stock-based compensation; contract research organizations (CRO) and other third parties that assist in managing, monitoring, and analyzing clinical trials; investigator and site fees; laboratory services; consultants; contract manufacturing services; non-clinical The Company records expenses related to clinical studies and manufacturing development activities based on its estimates of the services received and efforts expended pursuant to contracts with multiple CROs and manufacturing vendors that conduct and manage these activities on its behalf. The financial terms of these agreements are subject to negotiation, vary from contract to contract, and may result in uneven payment flows. There may be instances in which payments made to the Company’s vendors will exceed the level of services provided and result in a prepayment. Payments under some of these contracts depend on factors such as the successful enrollment of subjects and the completion of clinical trial milestones. In expensing service fees, the Company estimates the time period over which services will be performed, enrollment of subjects, number of sites activated and the level of effort to be expended in each period. If the actual timing of the performance of services or the level of effort varies from the Company’s estimate, the Company will adjust the accrued or prepaid expense balance accordingly. In 2022 and 2021, there have been no material differences from the Company’s estimates to the amounts actually incurred.
Development Financing Agreement	Development Financing Agreement The Company accounts for the Development Financing Agreement with Abingworth as a debt instrument. Accordingly, the Company has recorded payments received under the Financing Agreement as part of a development financing liability in the Company’s consolidated balance sheet. The liability is recorded at amortized cost and accreted to the contractual success fee amounts based on the estimated timing of regulatory approval and attainment of certain sales milestones using an imputed interest rate. Certain transaction fees incurred specifically to complete the Financing Agreement were capitalized and recorded as a reduction to the carrying amount of the development financing liability and are being amortized to interest expense using the effective interest rate method. There are several factors that could affect the estimated timing of regulatory approval and attainment of sales milestones, some of which are not entirely within the Company’s control. Therefore, the Company periodically reassesses the estimated timing of regulatory approval and attainment of sales milestones, and the expected contractual success fee payments due therefrom. If the timing and/or amount of such expected payments is materially different than original estimates, the Company will prospectively adjust the accretion of the development financing liability and the imputed interest rate. The Company identified certain contingent repayment features in the Financing Agreement that are required to be bifurcated from the debt host instrument as embedded derivative liabilities; however, the Company determined the fair value of these features, both individually and in the aggregate, was immaterial at inception and as of December 31, 2022. The fair value of these features will be assessed at each reporting date and will be marked to market, if material. To determine the amount to record for the embedded derivative liabilities, the Company must assess the probability of occurrence of various potential future
Pre-funded Warrants	Pre-funded Pursuant to the Company’s public equity offering co mpleted in pre-funded pre-funded pre-funded pre-funded paid-in Note 9—Stockholders’ Equity information.
Stock-Based Compensation	Stock-Based Compensation Stock-based compensation is measured at fair value on the grant date of the award. Compensation cost is recognized as expense on a straight-line basis over the vesting period for options with service conditions and forfeitures are accounted for as they occur. The Company uses the Black-Scholes option-pricing model to determine the fair value of stock option awards. The determination of fair value for stock-based awards using an option-pricing model requires management to make certain assumptions regarding subjective input variables such as expected term, dividends, volatility and risk-free rate. If actual results are not consistent with the Company’s assumptions used in making these estimates, the Company may be required to increase or decrease compensation expense, which could be material to the Company’s results of operations.
Income Taxes	Income Taxes The Company The accounting guidance for uncertainty in income taxes prescribes a recognition threshold and measurement attribute criteria for the financial recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination based on the technical merits of the position. The Company is required to file federal and state income tax returns in the United States. The preparation of these income tax returns requires the Company to interpret the applicable tax laws and regulations in effect that could affect the amount of tax paid to these jurisdictions. The Company records interest related to income tax reserves, if any, as interest expense, and any penalties would be recorded as other expense in the consolidated statements of operations and comprehensive loss.
Comprehensive Loss	Comprehensive Loss Comprehensive loss includes net loss and net unrealized gains and losses on marketable securities, which are presented in a single continuous statement. Other comprehensive (loss) gain is also disclosed in the consolidated balance sheets and statements of stockholders’ equity in accumulated other comprehensive income (loss), and is stated net of related tax effects, if any.
Net Loss Per Common Share	Net Loss Per Common Share Basic net loss per share of common stock is based on the weighted average number of shares of common stock and common stock equivalents outstanding during the period. The weighted-average common shares outstanding as of December 31, 2022 and 2021 includes pre-funded warrants to purchase up to 3,125,000 shares of common stock that were issued in connection with the November 2021 public offering, as discussed in Note 9—Stockholders’ Equity net loss per share of common stock is calculated as the weighted average number of shares of common stock outstanding adjusted to include the assumed exercises of stock options, if dilutive. In all periods presented, the Company’s outstanding stock options and incentive awards were excluded from the calculation of net loss per share because the effect would be antidilutive. The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts): Year Ended December 31, 2022 2021 Numerator: Net loss $ (106,001 ) $ (89,998 ) Denominator: Weighted average number of: Common stock shares outstanding 84,679,063 70,712,865 Pre-funded warrants outstanding 3,125,000 342,466 Total 87,804,063 71,055,331 Net loss per share $ (1.21 ) $ (1.27 ) The following table shows the total outstanding securities considered anti-dilutive and therefore excluded from the computation of diluted net loss per share (in thousands): Year Ended 2022 2021 Common stock options 13,930 10,791 Incentive awards 101 101 Total 14,031 10,892
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements ASU 2016-13 In June 2016, the FASB issued ASU No. 2016-13, Measurement of Credit Losses on Financial Instruments available-for-sale No. 2019-10, Financial Instruments—Credit Losses (Topic 326), Derivatives and Hedging (Topic 815) and Leases (Topic 842)

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Schedule of Fair Value Assets Measured on Recurring Basis	The following tables present the Company’s financial assets that are measured at fair value on a recurring basis using the above input categories (in thousands): As of December 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 9,770 $ — $ — $ 9,770 Total cash equivalents 9,770 — — 9,770 Marketable securities: U.S. and foreign commercial paper — 46,121 — 46,121 U.S. and foreign corporate debt securities — 24,807 — 24,807 Supranational debt securities — 12,890 — 12,890 U.S. agency securities — 7,759 — 7,759 U.S. treasury securities — 23,617 — 23,617 Total marketable securities — 115,194 — 115,194 Total assets measured at fair value $ 9,770 $ 115,194 $ — $ 124,964 As of December 31, 2021 Level 1 Level 2 Level 3 Total Cash equivalents: Money market funds $ 85,638 $ — $ — $ 85,638 Total cash equivalents 85,638 — — 85,638 Marketable securities: U.S. and foreign commercial paper — 28,760 — 28,760 U.S. and foreign corporate debt securities — 23,535 — 23,535 Asset-backed securities — 8,522 — 8,522 U.S. treasury securities — 7,979 — 7,979 Total marketable securities — 68,796 — 68,796 Total assets measured at fair value $ 85,638 $ 68,796 $ — $ 154,434
Computation of Basic and Diluted Net Loss per Share	The following table sets forth the computation of basic and diluted net loss per share (in thousands, except share and per share amounts): Year Ended December 31, 2022 2021 Numerator: Net loss $ (106,001 ) $ (89,998 ) Denominator: Weighted average number of: Common stock shares outstanding 84,679,063 70,712,865 Pre-funded warrants outstanding 3,125,000 342,466 Total 87,804,063 71,055,331 Net loss per share $ (1.21 ) $ (1.27 )
Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss per Share	The following table shows the total outstanding securities considered anti-dilutive and therefore excluded from the computation of diluted net loss per share (in thousands): Year Ended 2022 2021 Common stock options 13,930 10,791 Incentive awards 101 101 Total 14,031 10,892

Marketable Securities (Tables)

Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2022
Cash and Cash Equivalents [Abstract]
Marketable Available-for-Sale Securities	Marketable available-for-sale Amortized Unrealized Unrealized Estimated As of December 31, 2022: Cash equivalents: Money market funds $ 9,770 $ — $ — $ 9,770 Total cash equivalents 9,770 — — 9,770 Current marketable securities: U.S. and foreign commercial paper 46,121 — — 46,121 U.S. and foreign corporate debt securities 24,964 — (157 ) 24,807 Supranational debt securities 12,946 — (56 ) 12,890 U.S. agency securities 7,782 16 (39 ) 7,759 U.S. treasury securities 23,707 2 (92 ) 23,617 Total current marketable securities 115,520 18 (344 ) 115,194 Total marketable securities $ 125,290 $ 18 $ (344 ) $ 124,964 Amortized Gross Gross Estimated As of December 31, 2021: Cash equivalents: Money market funds $ 85,638 $ — $ — $ 85,638 Total cash equivalents 85,638 — — 85,638 Current marketable securities: U.S. and foreign commercial paper 28,760 — — 28,760 U.S. and foreign corporate debt securities 15,476 — (8 ) 15,468 Asset-backed securities 8,524 1 (3 ) 8,522 U.S. treasury securities 7,982 — (3 ) 7,979 Total current marketable securities 60,742 1 (14 ) 60,729 Non-current U.S. corporate debt securities 8,067 3 (2 ) 8,068 Total marketable securities $ 154,447 $ 4 $ (16 ) $ 154,435
Schedule of fair value of the Company marketable securities by contractual maturity	The following table shows the fair value of the Company’s marketable securities, by contractual maturity, as of December 31, 2022 (in thousands): Due less than 1 year $ 115,194 Due between 1 and 2 years — Total fair value $ 115,194

Certain Balance Sheet Items (Ta

Certain Balance Sheet Items (Tables)	12 Months Ended
	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Property and Equipment	Property and equipment are recorded at cost and consist of the following (in thousands): December 31, December 31, Leasehold improvements $ 2,429 $ 2,429 Office and computer equipment 290 290 Purchased software 44 44 Furniture and fixtures 687 539 Total 3,450 3,302 Less: Accumulated depreciation and amortization (2,749 ) (2,124 ) Property and equipment, net $ 701 $ 1,178
Other Accrued Liabilities	Other accrued liabilities consist of the following (in thousands): December 31, December 31, Accrued compensation $ 5,779 $ 3,986 Accrued professional fees and other 1,372 1,333 Current portion of operating lease liability 664 567 Total other accrued liabilities $ 7,815 $ 5,886

Development Financing Agreeme_2

Development Financing Agreement (Tables)	12 Months Ended
	Dec. 31, 2022
Debt Disclosure [Abstract]
Schedule of Changes in Fair Value of Liabilities	The following table sets forth a summary of the changes in the carrying value of the Company’s development financing liability (in thousands): Balance at December 31, 2021 $ 50,320 Cash received 25,000 Accretion of development financing liability 14,907 Balance at December 31, 2022 $ 90,227

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Summary of Maturities of Operating Lease Liabilities	As of December 31, 2022, the maturities of the Company’s operating lease liabilities were as follows (in thousands): Year ending December 31, 2023 $ 707 2024 30 Total undiscounted future minimum lease payments 737 Less imputed interest 43 Total operating lease liability 694 Less: current portion of operating lease liability 664 Long-term portion of lease liability $ 30

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2022
Equity [Abstract]
Summary of Reserved Shares of Common Stock for Future Issuances	As of December 31, 2022 and 2021, the Company had reserved shares of common stock for future issuances as follows: December 31, 2022 2021 Pre-funded 3,125,000 3,125,000 Equity award plans: Options and incentive awards outstanding, all equity plans 14,031,377 10,892,613 Equity awards available for future grant - 2013 Plan 2,680,621 1,588,613 Equity awards available for future grant - 2020 Plan — — Total shares of common stock reserved for future issuance 19,836,998 15,606,226

Stock Plans and Stock-Based C_2

Stock Plans and Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2022
Share-based Payment Arrangement [Abstract]
Summary of Stock Option Grants, Including Performance Options	The following table summarizes activity in the Company’s stock option grants: Shares Weighted- Weighted- Aggregate Outstanding as of December 31, 2021 10,791,431 $ 6.01 Options granted 3,692,868 2.94 Options exercised (3,124 ) 2.94 Options forfeited (403,210 ) 4.08 Options expired (147,770 ) 5.24 Outstanding as of December 31, 2022 13,930,195 $ 5.26 6.96 $ 26,089 Vested and expected to vest as of December 31, 2022 13,930,195 $ 5.26 6.96 $ 26,089 Exercisable as of December 31, 2022 9,004,373 $ 6.00 6.08 $ 13,858
Summary of Stock-Based Compensation Expense	Stock-based compensation expense is included in the consolidated statements of operations and comprehensive loss and is as follows (in thousands): Year Ended December 31, 2022 2021 Research and development $ 4,274 $ 4,470 General and administrative 5,243 5,526 Total stock-based compensation expense $ 9,517 $ 9,996
Estimated Weighted-Average Grant Date Fair Value	The following table presents the weighted-average assumptions the Company used in the Black-Scholes option-pricing model to derive the grant date fair values of stock options granted in each of the years presented Year Ended December 31, 2022 2021 Expected term (years) 6.0 6.1 Expected volatility 101 % 104 % Risk-free interest rate 1.8 % 0.9 % Expected dividend yield — — Weighted-average grant date fair value per share $ 2.33 $ 3.91

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Components of Deferred Tax Assets	Significant components of the Company’s deferred December 31, 2022 2021 Deferred tax assets: Federal and state net operating loss carryforwards $ 87,681 $ 129,898 State and federal research and development tax credit carryforwards 32,016 31,951 Intangibles and capitalized research and development 16,912 5,670 Stock-based compensation 6,624 5,329 Other 1,574 1,222 Total deferred tax assets 144,807 174,070 Deferred tax liabilities: Depreciation and amortization (79 ) (158 ) Other (36 ) (53 ) Total deferred tax liabilities (115 ) (211 ) Valuation allowance (144,692 ) (173,859 ) Net deferred tax assets $ — $ —
Summary of Reconciliation of Expected Statutory Federal Income Tax Provision to Actual Income Tax Provision	The following is a reconciliation of the expected statutory federal income tax provision to the actual income tax provision (in thousands): December 31, 2022 2021 Income tax benefit at federal statutory tax rate $ (22,260 ) $ (18,900 ) Change in valuation allowance (29,165 ) 14,739 Impairment of tax attributes 38,398 — Research credits (2,640 ) (2,802 ) Cancelled options 49 141 Development financing liability 12,301 6,654 Permanent differences 511 429 State income taxes, net of federal benefit 2,806 (267 ) Other, net — 6 Income tax (benefit) expense $ — $ —
Summary of Gross Unrecognized Tax Benefits	The following table summarizes activity related to the Company’s gross unrecognized tax benefits (in thousands): Balances as of December 31, 2020 $ 7,205 Increases related to prior year tax positions 9 Increases related to 2021 tax positions 783 Balances as of December 31, 2021 7,997 Decreases related to prior year tax positions (1,223 ) Increases related to 2022 tax positions 730 Balances as of December 31, 2022 $ 7,504

Organization and Description _2

Organization and Description of Business - Additional Information (Detail) $ / shares in Units, $ in Thousands			1 Months Ended	12 Months Ended
	Jan. 23, 2023 USD ($) $ / shares shares	Jan. 31, 2022 USD ($) INSTALLMENTS	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) segment shares	Dec. 31, 2021 USD ($)	Jan. 06, 2023 USD ($)	Nov. 30, 2021 $ / shares shares	Nov. 22, 2021 $ / shares shares
Class of Stock [Line Items]
Number of operating segments | segment				1
Net loss				$ (106,001)	$ (89,998)
Cash flows from operating activities				(84,080)	(69,431)
Accumulated deficit				(872,857)	$ (766,856)
Cash and cash equivalents and marketable securities				$ 135,500
Prefunded warrants [Member]
Class of Stock [Line Items]
Sale of Stock, Price Per Share | $ / shares							$ 3.9999	$ 3.9999
Number of common stock into which the class of warrant or right may be converted | shares				3,125,000			3,125,000	3,125,000
Subsequent Event [Member]
Class of Stock [Line Items]
Number of new stock issued during the period. | shares	11,821,428
Sale of Stock, Price Per Share | $ / shares	$ 7
Total gross offering proceeds	$ 92,400
Subsequent Event [Member] | Collaboration and License Agreement [Member]
Class of Stock [Line Items]
Upfront cash payment			$ 34,200			$ 34,200
Subsequent Event [Member] | Collaboration and License Agreement [Member] | Kaken Pharmaceutical Co., Ltd [Member]
Class of Stock [Line Items]
Upfront cash payment			34,200
Subsequent Event [Member] | Prefunded warrants [Member]
Class of Stock [Line Items]
Sale of Stock, Price Per Share | $ / shares	$ 6.9999
Number of common stock into which the class of warrant or right may be converted | shares	2,142,857
Abw Cyclops Spv Lp [Member]
Class of Stock [Line Items]
Proceeds from Lines of Credit		$ 75,000
Number of funding installments | INSTALLMENTS		3
Abw Cyclops Spv Lp [Member] | Financing agreement funding installments two [Member]
Class of Stock [Line Items]
Proceeds from Lines of Credit		$ 25,000
IPO [Member] | Subsequent Event [Member] | Collaboration and License Agreement [Member] | Kaken Pharmaceutical Co., Ltd [Member]
Class of Stock [Line Items]
Issuance of public equity offering			$ 92,400

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Schedule of Fair Value Assets Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 124,964	$ 154,434
Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,770	85,638
Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,770	85,638
Short-term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	115,194	68,796
Short-term Investments [Member] | U.S. and Foreign Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	46,121	28,760
Short-term Investments [Member] | U.S. and Foreign Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	24,807	23,535
Short-term Investments [Member] | Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		8,522
Short-term Investments [Member] | US Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	7,759
Short-term Investments [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	23,617	7,979
Short-term Investments [Member] | Supranational Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	12,890
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,770	85,638
Level 1 [Member] | Cash Equivalents [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,770	85,638
Level 1 [Member] | Cash Equivalents [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	9,770	85,638
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	115,194	68,796
Level 2 [Member] | Short-term Investments [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	115,194	68,796
Level 2 [Member] | Short-term Investments [Member] | U.S. and Foreign Commercial Paper [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	46,121	28,760
Level 2 [Member] | Short-term Investments [Member] | U.S. and Foreign Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	24,807	23,535
Level 2 [Member] | Short-term Investments [Member] | Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value		8,522
Level 2 [Member] | Short-term Investments [Member] | US Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	7,759
Level 2 [Member] | Short-term Investments [Member] | U.S. Treasury Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	23,617	$ 7,979
Level 2 [Member] | Short-term Investments [Member] | Supranational Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	$ 12,890

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2022	Nov. 30, 2021	Nov. 22, 2021
Product Information [Line Items]
Cash and cash equivalents, maturity description	90 days or less
Fair value of development financing liability	$ 79.5
Prefunded warrants [Member]
Product Information [Line Items]
Number of common stock into which the class of warrant or right may be converted	3,125,000	3,125,000	3,125,000
Sale of Stock, Price Per Share		$ 3.9999	$ 3.9999
Class of Warrant or Right, Exercise Price of Warrants or Rights		$ 0.0001	$ 0.0001
Maximum [Member]
Product Information [Line Items]
Short-term contractual maturities	1 year
Property and equipment, estimated useful lives	7 years
Minimum [Member]
Product Information [Line Items]
Short-term contractual maturities	1 year
Property and equipment, estimated useful lives	3 years

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Computation of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net loss	$ (106,001)	$ (89,998)
Denominator:
Common stock shares outstanding	84,679,063	70,712,865
Pre-funded warrants outstanding	3,125,000	342,466
Total, Basic	87,804,063	71,055,331
Total, Diluted	87,804,063	71,055,331
Net loss per share—basic	$ (1.21)	$ (1.27)
Net loss per share—diluted	$ (1.21)	$ (1.27)

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Anti-Dilutive Securities Excluded from the Computation of Diluted Net Loss per Share (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted loss per share	14,031	10,892
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted loss per share	13,930	10,791
Incentive Awards [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the computation of diluted loss per share	101	101

Marketable Securities - Additio

Marketable Securities - Additional Information (Detail) - Debt Securities [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Realized gains and losses	$ 0	$ 0
Marketable investments continuous unrealized loss position	$ 0	$ 0

Marketable Securities - Marketa

Marketable Securities - Marketable Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		$ 8,067
Estimated Fair Value	$ 115,194	60,729
Cash and Cash Equivalents [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	9,770	85,638
Estimated Fair Value	9,770	85,638
Cash and Cash Equivalents [Member] | Money Market Funds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	9,770	85,638
Estimated Fair Value	9,770	85,638
Current marketable securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	115,520	60,742
Unrealized Gains	18	1
Unrealized Losses	(344)	(14)
Estimated Fair Value	115,194	60,729
Current marketable securities [Member] | U.S. and Foreign Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	46,121	28,760
Estimated Fair Value	46,121	28,760
Current marketable securities [Member] | U.S. and Foreign Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	24,964	15,476
Unrealized Gains		0
Unrealized Losses	(157)	(8)
Estimated Fair Value	24,807	15,468
Current marketable securities [Member] | Asset-backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		8,524
Unrealized Gains		1
Unrealized Losses		(3)
Estimated Fair Value		8,522
Current marketable securities [Member] | U.S. Treasury Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	23,707	7,982
Unrealized Gains	2	0
Unrealized Losses	(92)	(3)
Estimated Fair Value	23,617	7,979
Current marketable securities [Member] | U.S. agency securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,782
Unrealized Gains	16
Unrealized Losses	(39)
Estimated Fair Value	7,759
Current marketable securities [Member] | Supranational Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	12,946
Unrealized Losses	(56)
Estimated Fair Value	12,890
Maketable Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	125,290	154,447
Unrealized Gains	18	4
Unrealized Losses	(344)	(16)
Estimated Fair Value	$ 124,964	154,435
Non-current marketable securities [Member] | U.S. and Foreign Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized Gains		3
Unrealized Losses		(2)
Estimated Fair Value		$ 8,068

Marketable Securities - Schedul

Marketable Securities - Schedule Of Fair Value Of The Company Marketable Securities By Contractual Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Contractual Obligation Fiscal Year Maturity Schedule [Line Items]
Due less than 1 year	$ 115,194
Due between 1 and 2 years	0
Total fair value	$ 115,194	$ 60,729

Certain Balance Sheet Items - P

Certain Balance Sheet Items - Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 3,450	$ 3,302
Less: Accumulated depreciation and amortization	(2,749)	(2,124)
Property and equipment, net	701	1,178
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,429	2,429
Office and Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	290	290
Purchased Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	44	44
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 687	$ 539

Certain Balance Sheet Items - A

Certain Balance Sheet Items - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 0.7	$ 0.7

Certain Balance Sheet Items - O

Certain Balance Sheet Items - Other Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Accrued compensation	$ 5,779	$ 3,986
Accrued professional fees and other	1,372	1,333
Current portion of operating lease liability	664	567
Total other accrued liabilities	$ 7,815	$ 5,886

In-License Agreement - Addition

In-License Agreement - Additional Information (Detail) - Janssen Pharmaceutical NV [Member] - USD ($)	1 Months Ended
	Jun. 30, 2006	Dec. 31, 2022	Dec. 31, 2021
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Accrued royalties		$ 0	$ 0
Maximum [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of royalty on net sales	8%

Development Financing Agreeme_3

Development Financing Agreement - Additional Information (Detail) - USD ($) $ in Millions				12 Months Ended
	Jan. 31, 2022	Nov. 30, 2021	Aug. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Jul. 30, 2021
Debt Instrument [Line Items]
Description Of Percentage Fixed Success Payments			2.0
Repayments of Lines of Credit			$ 10
Description Of Percentage Variable Success Payments			1.1
Description Of Aggregate Return From The Funds Provided			3.1
Aggregate Return Percentage From The Funds Provided			$ 232.5
Percentage of Accelerate Payment Payable On Funds provided			1.35
Description Repayments On Funds Provided Upon Termination Of Financing Agreement			2.0
Percentage of Unamortized Portion of The Development Financing Liability				19.20%
Fixed Success Payments [Member]
Debt Instrument [Line Items]
Anniversary Payments Due Year One			$ 15
Anniversary Payments Due Year Two			22.5
Anniversary Payments Due Year Three			22.5
Anniversary Payments Due Year Four			25
Anniversary Payments Due Year Five			27.5
Anniversary Payments Due Year Six			27.5
Variable Success Payments [Member]
Debt Instrument [Line Items]
Payments Upon Reaching Cumulative US Product Sales Thresholds Year One			17.5
Payments Upon Reaching Cumulative US Product Sales Thresholds Year Two			27.5
Payments upon reaching product sales run rate			37.5
Installment Funding Number Three [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit	$ 25
ABW Cyclops SPV LP [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity						$ 75
Proceeds from Lines of Credit	$ 75
ABW Cyclops SPV LP [Member] | Installment Funding Number One [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit			$ 25
ABW Cyclops SPV LP [Member] | Installment Funding Number Two [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit		$ 25
Financing Agreement Termination Event Condition One [Member] | ABW Cyclops SPV LP [Member]
Debt Instrument [Line Items]
Percentage of amount to be paid by entity upon the termination of the agreement					310%
Financing Agreement Termination Event Condition Two [Member] | ABW Cyclops SPV LP [Member]
Debt Instrument [Line Items]
Percentage of amount to be paid by entity upon the termination of the agreement					200%
Financing Agreement Termination Event Condition Three [Member] | ABW Cyclops SPV LP [Member]
Debt Instrument [Line Items]
Percentage of amount to be paid by entity upon the termination of the agreement					100%

Development Financing Agreeme_4

Development Financing Agreement - Schedule of Changes in Fair Value of Liabilities (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Debt Disclosure [Abstract]
Balance, beginning of period	$ 50,320
Cash received	25,000
Accretion of development financing liability	14,907
Balance, end of period	$ 90,227

Leases - Summary of Maturities

Leases - Summary of Maturities of Operating Lease Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
2023	$ 707
2024	30
Total undiscounted future minimum lease payments	737
Less imputed interest	43
Total operating lease liability	694	$ 1,300
Less: current portion of operating lease liability	664	567
Long-term portion of lease liability	$ 30	$ 695

Leases - Additional Information

Leases - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) ft² Facility	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Weighted average remaining lease term	1 year 1 month 6 days	2 years 1 month 6 days
Lease, option to extend	option to extend for an additional 5 years
Weighted average lease discount rate	12.60%
Operating lease right-of-use asset	$ 169	$ 254
Operating lease liability	694	1,300
Short term portion of operating lease liability	$ 664	$ 567
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Accrued Liabilities, Current	Other Accrued Liabilities, Current
Lease Facility [Member]
Lessee, Lease, Description [Line Items]
Number of leased facilities | Facility	1
Area of office space | ft²	17,698
Lease start date	Jan. 16, 2014
Operating Expense [Member]
Lessee, Lease, Description [Line Items]
Lease costs	$ 700	$ 600

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($)			12 Months Ended
	Mar. 12, 2021	Jan. 15, 2021	Dec. 31, 2022	Dec. 31, 2021
Loss Contingencies [Line Items]
Loss Contingency, Lawsuit Filing Date		January 15, 2021
Loss Contingency, Name of Plaintiff		Genfit S.A
Loss Contingency, Allegations		alleging misappropriation of trade secrets and related causes of action based on the Company’s receipt of a Genfit protocol synopsis for Genfit’s Phase 3 clinical trial of its drug candidate elafibranor in patients with primary biliary cholangitis
Loss Contingency, Actions Taken by Defendant		On February 21, 2023, the parties entered into a Settlement Agreement and the action was dismissed with prejudice. The Company did not admit to any liability and the litigation has been resolved completely.
Indemnification liabilities			$ 0	$ 0
Loss Contingency, Actions Taken by Court, Arbitrator or Mediator	On March 12, 2021, the Court granted a Temporary Restraining Order (later converted to a Preliminary Injunction), prohibiting the Company from accessing or disseminating the protocol synopsis, using any Genfit trade secrets contained therein or destroying any evidence related thereto.
Pending Litigation [Member]
Loss Contingencies [Line Items]
Loss Contingency, Lawsuit Filing Date			April 16, 2021

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - $ / shares	Jan. 23, 2023	Dec. 31, 2022	Dec. 31, 2021	Nov. 30, 2021	Nov. 22, 2021
Class of Stock [Line Items]
Preferred stock, shares authorized		10,000,000	10,000,000
Common stock, shares authorized		200,000,000	200,000,000
Prefunded warrants [Member]
Class of Stock [Line Items]
Number of common stock into which the class of warrant or right may be converted		3,125,000		3,125,000	3,125,000
Sale of Stock, Price Per Share				$ 3.9999	$ 3.9999
Class of Warrant or Right, Exercise Price of Warrants or Rights				$ 0.0001	$ 0.0001
Subsequent Event [Member]
Class of Stock [Line Items]
Number of new stock issued during the period.	11,821,428
Sale of Stock, Price Per Share	$ 7
Subsequent Event [Member] | Prefunded warrants [Member]
Class of Stock [Line Items]
Number of common stock into which the class of warrant or right may be converted	2,142,857
Sale of Stock, Price Per Share	$ 6.9999
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.0001

Stockholder's Equity - Summary

Stockholder's Equity - Summary of Reserved Shares of Common Stock for Future Issuances (Detail) - shares	Dec. 31, 2022	Dec. 31, 2021
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	19,836,998	15,606,226
CBAYEquity incentive plan two thousand and thirteen [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	2,680,621	1,588,613
CBAYEquity incentive plan two thousand and twenty plan [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	0	0
Options and Incentive awards [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	14,031,377	10,892,613
Prefunded warrants [Member]
Class of Stock [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	3,125,000	3,125,000

Stock Plans and Stock-Based C_3

Stock Plans and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2017	Jan. 01, 2022	Apr. 30, 2014	Jan. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of options exercised		$ 0.2	$ 0.2
Fair value of options vested		0.6	$ 0.7
Unamortized employee and non-employee stock-based compensation expense		$ 14.7
Unamortized employee and non-employee stock-based compensation expense recognized period		2 years 4 months 24 days
Share reserved for issue		19,836,998	15,606,226
Stock options outstanding		13,930,195	10,791,431
Equity Incentive Plan Two Thousand and Twenty Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, expiration period	10 years
Share based compensation arrangement by share based payment award, exercise price percentage				85%
Shares available for grant		0
2013 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement percentage increase in share reserved	5%
Shares available for grant		2,680,621
Share reserved for issue						4,234,053
2013 Equity Incentive Plan [Member] | Incentive Stock Options for Employees and Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, exercise price percentage	100%
2013 Equity Incentive Plan [Member] | Nonqualified Options to Employees, Directors and Consultants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, exercise price percentage	85%
2013 Equity Incentive Plan [Member] | Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, exercise price percentage	85%
Share based compensation arrangement by share based payment award, award vesting period	4 years
2013 Equity Incentive Plan [Member] | Stock Options to 10% Stockholders [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award, exercise price percentage					110%
Share based compensation arrangement by share based payment award, award vesting period					5 years
Incentive Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share reserved for issue							252,752
Exercisable weighted average price per share								$ 5.21
Stock options outstanding		101,182	101,182

Stock Plans and Stock-Based C_4

Stock Plans and Stock-Based Compensation - Summary of Stock Option Grants, Including Performance Options (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares shares
Shares Subject to Outstanding Options
Outstanding at the beginning of period | shares	10,791,431
Options granted | shares	3,692,868
Options exercised | shares	(3,124)
Options forfeited | shares	(403,210)
Options expired | shares	(147,770)
Outstanding as end of period | shares	13,930,195
Vested and expected to vest | shares	13,930,195
Exercisable | shares	9,004,373
Weighted-Average Exercise Price of Options
Outstanding at the beginning of period | $ / shares	$ 6.01
Options granted | $ / shares	2.94
Options exercised | $ / shares	2.94
Options forfeited | $ / shares	4.08
Options expired | $ / shares	5.24
Outstanding as end of period | $ / shares	5.26
Vested and expected to vest | $ / shares	5.26
Exercisable | $ / shares	$ 6
Weighted-Average Remaining Contractual Term (Years)
Outstanding	6 years 11 months 15 days
Vested and expected to vest	6 years 11 months 15 days
Exercisable	6 years 29 days
Aggregate Intrinsic Value (In Thousands)
Outstanding | $	$ 26,089
Vested and expected to vest | $	26,089
Exercisable | $	$ 13,858

Stock Plans and Stock-Based C_5

Stock Plans and Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 9,517	$ 9,996
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	4,274	4,470
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 5,243	$ 5,526

Stock Plans and Stock-Based C_6

Stock Plans and Stock-Based Compensation - Estimated Weighted-Average Grant Date Fair Value (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 years	6 years 1 month 6 days
Expected volatility	101%	104%
Risk-free interest rate	1.80%	0.90%
Expected dividend yield	0%	0%
Weighted-average grant date fair value per share	$ 2.33	$ 3.91

401(k) Plan - Additional Inform

401(k) Plan - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Retirement Benefits [Abstract]
Employees contribution to qualified savings plan	$ 750,000	$ 750,000

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2018	Dec. 31, 2017
Income Tax [Line Items]
Description of net operating loss carryforwards, expire period		The state net operating loss carryforwards will expire beginning in 2028 through 2040. The federal research and development and federal orphan drug tax credit carryforwards expire 2033 through 2042, and the state tax credit will carry forward indefinitely.
Provision for income taxes		$ 0	$ 0
Net valuation allowance increase (decrease)		(29,200)	$ 14,700
Significant change to its unrecognized tax benefits over the next twelve months		$ 0
Income tax examination years		the tax years 2004 to 2022 remain open for income tax examination by tax authorities
Alternate Minimum Tax Rate	15%
Revenues	$ 1,000,000
Write off of tax attribute due to limitation		$ 38,400
Minimum [Member]
Income Tax [Line Items]
Open tax year		2004
Maximum [Member]
Income Tax [Line Items]
Open tax year		2022
Domestic Tax Authority [Member]
Income Tax [Line Items]
Federal net operating loss		$ 346,000
Description of net operating loss carryforwards, expire period		federal research and development and federal orphan drug tax credit carryforwards expire 2033 through 2042
Net operating loss carryforward		$ 346,000
Research and development tax credit carry forwards		28,100
Domestic Tax Authority [Member] | Orphan Drug [Member]
Income Tax [Line Items]
Research and development tax credit carry forwards		$ 4,100
Domestic Tax Authority [Member] | Minimum [Member]
Income Tax [Line Items]
NOL carry forward expiry date		2024
Domestic Tax Authority [Member] | Maximum [Member]
Income Tax [Line Items]
NOL carry forward expiry date			2037
State and Local Jurisdiction [Member]
Income Tax [Line Items]
Federal net operating loss		$ 214,900
Net operating loss carryforward		214,900
Research and development tax credit carry forwards		$ 9,200
State and Local Jurisdiction [Member] | Federal [member]
Income Tax [Line Items]
Federal net operating loss				$ 266,900	$ 79,100
Net operating loss carryforward				$ 266,900	$ 79,100
State and Local Jurisdiction [Member] | Minimum [Member] | Federal [member]
Income Tax [Line Items]
NOL carry forward expiry date		2028
State and Local Jurisdiction [Member] | Maximum [Member] | Federal [member]
Income Tax [Line Items]
NOL carry forward expiry date		2040
Federal And State Tax Authority [Member]
Income Tax [Line Items]
Cumulative percentage change in ownership percentage permissible		50%
Period for considering the cumulative percentage change in ownership percentage		3 years

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Federal and state net operating loss carryforwards	$ 87,681	$ 129,898
State and federal research and development tax credit carryforwards	32,016	31,951
Intangibles and capitalized research and development	16,912	5,670
Stock based compensation	6,624	5,329
Other	1,574	1,222
Total deferred tax assets	144,807	174,070
Deferred tax liabilities:
Depreciation and amortization	(79)	(158)
Other	(36)	(53)
Total deferred tax liabilities	(115)	(211)
Valuation allowance	(144,692)	(173,859)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliation of Expected Statutory Federal Income Tax Provision to Actual Income Tax Provision (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income tax benefit at federal statutory tax rate	$ (22,260)	$ (18,900)
Change in valuation allowance	(29,165)	14,739
Impairment of tax attributes	38,398	0
Research credits	(2,640)	(2,802)
Cancelled options	49	141
Development financing liability	12,301	6,654
Permanent differences	511	429
State income taxes, net of federal benefit	2,806	(267)
Other, net	0	6
Income tax (benefit) expense	$ 0	$ 0

Income Taxes - Summary of Gross

Income Taxes - Summary of Gross Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Balance at beginning of period	$ 7,997	$ 7,205
Increases related to prior year tax positions		9
Decreases related to prior year tax positions	(1,223)
Increases related to tax positions	730	783
Balance at end of period	$ 7,504	$ 7,997

Subsequent Events - Additional

Subsequent Events - Additional Information (Detail) $ / shares in Units, $ in Millions, ¥ in Billions		1 Months Ended		12 Months Ended
	Jan. 23, 2023 $ / shares shares	Jan. 31, 2023 USD ($)	Jan. 31, 2023 JPY (¥)	Dec. 31, 2023 USD ($)	Jan. 06, 2023 USD ($)	Dec. 31, 2022 shares	Nov. 30, 2021 $ / shares shares	Nov. 22, 2021 $ / shares shares
Prefunded warrants [Member]
Subsequent Event [Line Items]
Sale of Stock, Price Per Share							$ 3.9999	$ 3.9999
Class of Warrant or Right, Exercise Price of Warrants or Rights							$ 0.0001	$ 0.0001
Number of common stock into which the class of warrant or right may be converted | shares						3,125,000	3,125,000	3,125,000
Subsequent Event [Member]
Subsequent Event [Line Items]
Number of new stock issued during the period. | shares	11,821,428
Sale of Stock, Price Per Share	$ 7
Subsequent Event [Member] | Prefunded warrants [Member]
Subsequent Event [Line Items]
Sale of Stock, Price Per Share	6.9999
Class of Warrant or Right, Exercise Price of Warrants or Rights	$ 0.0001
Number of common stock into which the class of warrant or right may be converted | shares	2,142,857
Subsequent Event [Member] | Collaboration and License Agreement [Member]
Subsequent Event [Line Items]
Potential milestone payments		$ 128	¥ 17
Upfront cash payment | $		$ 34.2			$ 34.2
Sale of Stock, Consideration Received on Transaction | $				$ 92.4