Atara Biotherapeutics (ATRA) 10-K 8 Feb 23 2022 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2022	Jan. 31, 2023	Jun. 30, 2022
Cover [Abstract]
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	ATRA
Entity Registrant Name	ATARA BIOTHERAPEUTICS, INC.
Entity Central Index Key	0001604464
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Entity File Number	001-36548
Entity Tax Identification Number	46-0920988
Entity Address, Address Line One	2380 Conejo Spectrum Street
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Thousand Oaks
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	91320
City Area Code	805
Local Phone Number	623-4211
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes
Document Annual Report	true
Document Transition Report	false
ICFR Auditor Attestation Flag	true
Auditor Firm ID	34
Auditor Name	DELOITTE & TOUCHE LLP
Auditor Location	San Francisco, California
Entity Public Float			$ 715,382,568
Entity Common Stock, Shares Outstanding		95,926,711
Documents Incorporated by Reference	Portions of the Registrant’s definitive proxy statement relating to its 2023 Annual Meeting of Stockholders are incorporated by reference into Part III of this Report where indicated. Such proxy statement will be filed with the U.S. Securities and Exchange Commission within 120 days after the end of the fiscal year to which this report relates.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 92,942	$ 106,084
Short-term investments	149,877	264,984
Restricted cash	146	194
Accounts receivable	40,221	986
Inventories	1,586	0
Other current assets	10,308	12,373
Total current assets	295,080	384,621
Property and equipment, net	6,300	53,780
Operating lease assets	68,022	26,159
Restricted cash - long-term	0	1,200
Other assets	7,018	2,367
Total assets	376,420	468,127
Current liabilities:
Accounts payable	6,871	17,368
Accrued compensation	17,659	25,150
Accrued research and development expenses	24,992	13,451
Deferred revenue	8,000	40,760
Other current liabilities	21,394	9,057
Total current liabilities	78,916	105,786
Deferred revenue - long-term	77,000	55,708
Operating lease liabilities - long-term	58,064	25,518
Liability related to the sale of future royalties - long-term	30,236	0
Other long-term liabilities	5,564	1,501
Total liabilities	249,780	188,513
Commitments and contingencies (Note 10)
Stockholders’ equity:
Common stock-$0.0001 par value, 500,000 shares authorized as of December 31, 2022 and 2021, respectively; 95,927 and 91,671 shares issued and outstanding as of December 31, 2022 and 2021, respectively	10	9
Additional paid-in capital	1,821,721	1,744,695
Accumulated other comprehensive (loss) income	(2,067)	(368)
Accumulated deficit	(1,693,024)	(1,464,722)
Total stockholders’ equity	126,640	279,614
Total liabilities and stockholders’ equity	$ 376,420	$ 468,127

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, shares authorized	500,000,000	500,000,000
Common stock, shares issued	95,927,000	91,671,000
Common stock, shares outstanding	95,927,000	91,671,000

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Statement [Abstract]
License and collaboration revenue	$ 63,573	$ 20,340	$ 0
Operating expenses:
Research and development	272,533	282,001	244,650
General and administrative	71,553	78,801	64,402
Total operating expenses	344,086	360,802	309,052
Loss from operations	(280,513)	(340,462)	(309,052)
Other income (expense), net:
Gain on sale of ATOM Facility	50,237	0	0
Interest and other income, net	1,986	367	2,447
Total other income (expense), net, Total	52,223	367	2,447
Loss before provision for income taxes	(228,290)	(340,095)	(306,605)
Provision for income taxes	12	46	15
Net loss	(228,302)	(340,141)	(306,620)
Other comprehensive (loss) gain:
Unrealized (loss) gain on available-for-sale securities	(1,699)	(664)	76
Comprehensive loss	$ (230,001)	$ (340,805)	$ (306,544)
Net loss per common share:
Basic net loss per common share	$ (2.24)	$ (3.63)	$ (4.15)
Diluted net loss per common share	$ (2.24)	$ (3.63)	$ (4.15)
Basic weighted-average shares outstanding	101,990	93,670	73,973
Diluted weighted-average shares outstanding	101,990	93,670	73,973

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Common Stock At The Market Offering	Additional Paid-in Capital	Additional Paid-in Capital At The Market Offering	Accumulated Other Comprehensive (Loss) Income	Accumulated Deficit
Beginning balance at Dec. 31, 2019	$ 290,781	$ 6		$ 1,108,516		$ 220	$ (817,961)
Beginning balance (in shares) at Dec. 31, 2019		56,806
Issuance of common stock and pre-funded warrants through underwritten offering, net of offering costs	353,588		$ 2		$ 353,586
Issuance of common stock and pre-funded warrants through underwritten offering, net of offering costs, shares			20,060
Issuance of common stock, net of commissions and offering costs, value	68,004			68,004
Issuance of common stock, net of commissions and offering costs, shares		4,786
Exercise of pre-funded warrants, shares		57
RSU settlements, net of shares withheld	(1,521)			(1,521)
RSU settlements, net of shares withheld, shares		1,112
Issuance of common stock pursuant to employee stock awards	6,680			6,680
Issuance of common stock pursuant to employee stock awards, shares		551
Stock-based compensation expense	51,351			51,351
Net loss	(306,620)						(306,620)
Unrealized (loss) gain on available-for-sale securities	76					76
Ending balance at Dec. 31, 2020	462,339	$ 8		1,586,616		296	(1,124,581)
Ending balance (in shares) at Dec. 31, 2020		83,372
Issuance of common stock, net of commissions and offering costs, value	98,697	$ 1		98,696
Issuance of common stock, net of commissions and offering costs, shares		6,241
RSU settlements, net of shares withheld	(1,244)			(1,244)
RSU settlements, net of shares withheld, shares		1,492
Issuance of common stock pursuant to employee stock awards	6,762			6,762
Issuance of common stock pursuant to employee stock awards, shares		566
Stock-based compensation expense	53,865			53,865
Net loss	(340,141)						(340,141)
Unrealized (loss) gain on available-for-sale securities	(664)					(664)
Ending balance at Dec. 31, 2021	279,614	$ 9		1,744,695		(368)	(1,464,722)
Ending balance (in shares) at Dec. 31, 2021		91,671
Issuance of common stock, net of commissions and offering costs, value	21,891			21,891
Issuance of common stock, net of commissions and offering costs, shares		1,619
RSU settlements, net of shares withheld	(623)	$ 1		(624)
RSU settlements, net of shares withheld, shares		2,204
Issuance of common stock pursuant to employee stock awards	1,921			1,921
Issuance of common stock pursuant to employee stock awards, shares		433
Stock-based compensation expense	53,838			53,838
Net loss	(228,302)						(228,302)
Unrealized (loss) gain on available-for-sale securities	(1,699)					(1,699)
Ending balance at Dec. 31, 2022	$ 126,640	$ 10		$ 1,821,721		$ (2,067)	$ (1,693,024)
Ending balance (in shares) at Dec. 31, 2022		95,927

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Parenthetical) - Common Stock - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Underwritten Public Offering
Stock issuance, discounts, commissions and offering costs			$ 583
At The Market Offering
Stock issuance, discounts, commissions and offering costs	$ 517	$ 2,501	$ 1,887

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating activities
Net loss	$ (228,302)	$ (340,141)	$ (306,620)
Adjustments to reconcile net loss to net cash used in operating activities:
Gain on sale of ATOM Facility	(50,237)	0	0
Stock-based compensation expense	53,838	53,865	51,351
Depreciation and amortization expense	5,653	9,345	8,332
Non-cash operating lease expense	8,915	1,948	1,457
Amortization of investment premiums	1,024	1,769	828
Other non-cash items, net	147	108	208
Changes in operating assets and liabilities:
Accounts receivable	(39,235)	264	(1,250)
Increase (Decrease) in Inventories	(1,586)	0	0
Other current assets	1,836	8,182	(8,666)
Operating lease assets	0	0	886
Other assets	(266)	(1,727)	(219)
Accounts payable	(9,211)	9,067	(815)
Accrued compensation	(7,491)	4,692	5,752
Accrued research and development expenses	11,541	(2,362)	7,472
Other current liabilities	2,067	1,618	(187)
Deferred revenue	(11,468)	35,218	61,250
Operating lease liabilities	(8,009)	(1,859)	(1,316)
Other long-term liabilities	354	(509)	778
Net cash used in operating activities	(270,430)	(220,522)	(180,759)
Investing activities
Purchases of short-term investments	(180,589)	(301,129)	(425,868)
Proceeds from maturities and sales of short-term investments	292,973	333,967	309,653
Purchases of property and equipment	(4,193)	(10,580)	(4,513)
Net proceeds from sale of ATOM Facility	94,765	0	0
Net cash provided by (used in) investing activities	202,956	22,258	(120,728)
Financing activities
Proceeds from sale of common stock and pre-funded warrants in underwritten offerings, net	0	0	353,780
Proceeds from issuance of common stock through ATM facilities, net	21,891	98,697	69,189
Proceeds from employee stock awards	1,921	6,762	6,680
Proceeds from sale of future revenues, net	30,605	0	0
Taxes paid related to net share settlement of restricted stock units	(623)	(1,244)	(1,521)
Principal payments on finance lease obligations	(518)	(254)	(389)
Other financing activities, net	(192)	(17)	(165)
Net cash provided by financing activities	53,084	103,944	427,574
Increase (decrease) in cash, cash equivalents and restricted cash	(14,390)	(94,320)	126,087
Cash, cash equivalents and restricted cash at beginning of period	107,478	201,798	75,711
Cash, cash equivalents and restricted cash at end of period	93,088	107,478	201,798
Non-cash investing and financing activities
Property and equipment purchases included in accounts payable and other accrued liabilities	61	2,139	326
Accrued costs related to underwritten public offering	0	0	192
Accrued costs related to ATM facility	0	87	0
Accrued transaction costs related to sale of future revenues	332	0	0
Supplemental cash flow disclosure
Cash paid for interest	335	32	62
Cash paid for income taxes	$ 19	$ 15	$ 10

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2022
Description Of Business [Abstract]
Description of Business	1. Description of Business Atara Biotherapeutics, Inc. (“Atara”, “we”, “our” or “the Company”) was incorporated in August 2012 in Delaware . Atara is a leader in T-cell immunotherapy, leveraging its novel allogeneic Epstein-Barr Virus (“EBV”) T-cell platform to develop transformative therapies for patients with cancer and autoimmune disease. We have several T-cell immunotherapies in clinical development and are progressing multiple next-generation allogeneic chimeric antigen receptor T-cell (“CAR T”) programs. Our most advanced T-cell immunotherapy program, tab-cel ® (tabelecleucel), has received marketing authorization approval by the European Commission (“EC”) for commercial sale and use in the European Union (“EU”) and is currently in Phase 3 development in the US. In October 2021, we entered into a commercialization agreement (“Pierre Fabre Commercialization Agreement”) with Pierre Fabre Medicament (“Pierre Fabre”), as amended in September 2022, pursuant to which we granted to Pierre Fabre an exclusive, field-limited license to commercialize and distribute tab-cel in Europe and select emerging markets in the Middle East, Africa, Eastern Europe and Central Asia (the “Territory”), following regulatory approval. We retain full rights to tab-cel in other major markets, including North America, Asia Pacific and Latin America. See Note 5 for further information. In December 2020, we entered into a research, development and license agreement (“Bayer License Agreement”) with Bayer AG (“Bayer”) pursuant to which we granted to Bayer an exclusive, field-limited license under the applicable patents and know-how owned or controlled by us and our affiliates covering or related to ATA2271 and ATA3271. In March 2021, as contemplated under the Bayer License Agreement and to further advance our collaboration, we entered into (i) a Manufacturing and Supply Agreement; (ii) a Pharmacovigilance Agreement; (iii) a Quality Agreement; and (iv) a Technology Transfer Agreement (collectively, the Bayer License Agreement, the Manufacturing and Supply Agreement and the Technology Transfer Agreement are referred to as the “Bayer Agreements”). In May 2022, Bayer notified us of its decision to terminate the Bayer Agreements and on August 2, 2022, we entered into the Termination, Amendment and Program Transfer Agreement with Bayer which terminated the Bayer Agreements (the “Bayer Termination Agreement”) and returned full product development and commercialization rights related to ATA2271 and ATA3271 to us, effective as of July 31, 2022. See Note 5 for further information. We have licensed rights to T-cell product candidates from Memorial Sloan Kettering Cancer Center (“MSK”), rights related to our next-generation CAR T programs from MSK and from H. Lee Moffitt Cancer Center (“Moffitt”), and rights to know-how and technology from the Council of the Queensland Institute of Medical Research (“QIMR Berghofer”). See Note 10 for further information. In January 2022, we entered into an asset purchase agreement with FUJIFILM Diosynth Biotechnologies California, Inc. (“FDB”) and, for certain limited purposes, FUJIFILM Holdings America Corporation, to sell all of the Company’s right, title and interest in and to certain assets related to the Atara T-Cell Operations and Manufacturing facility (“ATOM Facility”) located in Thousand Oaks, California for $ 100 million in cash, subject to potential post-closing adjustments pursuant to the asset purchase agreement (the “Fujifilm Transaction”). The closing of the Fujifilm Transaction occurred on April 4, 2022, at which time 136 of our ATOM Facility employees transitioned to FDB as part of the transaction. We also entered into a Master Services and Supply Agreement and related Statements of Work with FDB (collectively the “Fujifilm MSA”) which became effective upon the closing and could extend for up to ten years. Pursuant to the Fujifilm MSA, FDB will supply us with specified quantities of our cell therapy product candidates and any products approved by regulatory authorities, manufactured in accordance with cGMP standards. See Notes 7, 8, and 10 for further information. In August 2022, we announced a reduction in force that reduced our workforce by approximately 20 %. We expect to recognize restructuring charges of $ 6.0 million in total for severance and related benefits for employees laid off under the reduction in force. These charges are primarily one-time termination benefits and are all cash charges. Refer to Note 9 for further information. Certain prior year amounts, which are not material, have been reclassified to conform to current year presentation in the Consolidated Statements of Cash Flows and Notes to Consolidated Financial Statements.

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 Principles of Consolidation The consolidated financial statements include the accounts of Atara and our wholly owned subsidiaries. All intercompany balances and transactions are eliminated in consolidation. Segment and Geographic Information We operate and manage our business as one operating and reportable segment, which is the business of developing therapeutics. Our Chief Executive Officer, who is our chief operating decision maker, reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance. Substantially all of our assets are located in the U.S. Of the $ 63.6 million license and collaboration revenue recognized in 2022 , $ 61.8 million related to our agreements with Bayer, a German company, and $ 1.8 million related to our agreements with Pierre Fabre, a French company. Use of Estimates We prepare our consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which requires us to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and accompanying notes. The level of uncertainty in estimates and assumptions increases with the length of time until the underlying transactions are completed. Significant estimates and assumptions relied upon in preparing these financial statements include those related to revenue recognition, accrued research and development expenses, stock-based compensation expense and income taxes. Additionally, we use available market information to assess the fair value of our short-term investments. Actual results could differ materially from those estimates. If actual amounts differ from estimates, we include the updates in our consolidated results of operations in the period the actual amounts become known. Historically, the aggregate differences, if any, between our estimates and actual amounts in any year have not had a material effect on our consolidated financial statements. Liquidity Risk We have incurred significant operating losses since inception and have relied primarily on public and private equity financings and receipts from commercialization and license and collaboration agreements to fund our operations. As we continue to incur losses, our transition to profitability will depend on the successful development, approval and commercialization of product candidates and on the achievement of sufficient revenues to support our cost structure. We may never achieve sustained operating cash inflows or profitability. We expect that existing cash, cash equivalents and short-term investments as of December 31, 2022 , together with the $ 40.0 million received in January 2023 for achievement of certain milestones under the Pierre Fabre Commercialization Agreement, will be sufficient to fund our planned operations for at least the next twelve months from the date of issuance of these financial statements. However, the uncertainties inherent in Atara’s future operations and in our ability to obtain additional funding may raise substantial doubt about our ability to continue as a going concern in future reporting periods. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. Although we have been successful in raising capital in the past, and expect to continue to raise capital as required, there is no assurance that we will be successful in obtaining additional funding on terms acceptable to us, if at all. If we are unable to obtain sufficient funding on acceptable terms, we could be forced to delay, limit, reduce or terminate preclinical studies, clinical studies or other development activities for one or more of our product candidates. Concentration of Credit Risk and Other Uncertainties We place cash and cash equivalents in the custody of financial institutions that management believes are of high credit quality, the amount of which at times, may be in excess of the amount insured by the Federal Deposit Insurance Corporation. We also make short-term investments in money market funds; U.S. Treasury, government agency and corporate debt obligations; commercial paper; certificates of deposit; and asset-backed securities, which can be subject to certain credit risk. However, we mitigate the risks by investing in high-grade instruments, limiting our exposure to any one issuer and monitoring the ongoing creditworthiness of the financial institutions and issuers. Currency Translation Transactions and monetary assets and liabilities that are denominated in a foreign currency are translated into U.S. dollars at the current exchange rate on the transaction date and as of each balance sheet date, respectively, with gains or losses on foreign exchange changes recognized in interest and other income (expense), net in the consolidated statements of operations and comprehensive loss. Foreign currency-denominated monetary assets and liabilities as of December 31, 2022 were not material. Cash, Cash Equivalents and Short-Term Investments Cash and cash equivalents are defined as highly liquid investments with original maturities of 90 days or less at the date of purchase. Investments with original maturities of greater than 90 days are classified as short-term investments on the balance sheet. As our entire investment portfolio is considered available for use in current operations, we classify all investments as available-for-sale and as current assets, even though the stated maturity may be more than one year from the current balance sheet date. Available-for-sale securities are carried at fair value, with unrealized gains and losses reported in accumulated other comprehensive loss, which is a separate component of stockholders’ equity in the consolidated balance sheet. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity, which are both recorded to interest and other income (expense), net in the consolidated statements of operations and comprehensive loss. Changes in the fair value of available-for-sale securities impact the consolidated statements of operations and comprehensive loss only when such securities are sold, if an allowance for credit losses is recognized or if an impairment is recognized. Realized gains and losses on the sale of securities are determined by specific identification of each security’s cost basis. We regularly review our investment portfolio to determine if any security is impaired, which would require us to record an allowance for credit losses or impairment charge in the period any such determination is made. In making this judgment, we evaluate, among other things, the duration and extent to which the fair value of a security is less than its cost, our intent to sell or whether it is more likely than not that we will be required to sell the security before recovery of its amortized cost basis, the financial condition of the issuer and any changes thereto, and, as necessary, the portion of a decline in fair value that is credit-related. This assessment could change in the future due to new developments or changes in assumptions related to any particular security. Realized gains and losses, allowances for credit losses and impairments on available-for-sale securities, if any, are recorded to interest and other income, net in the statements of operations and comprehensive loss. Fair Value Measurement The carrying amounts of certain of our financial instruments including cash equivalents, accounts receivable, other current assets, accounts payable and accrued liabilities approximate fair value due to their short maturities. Short-term investments are comprised of available-for-sale securities, which are carried at fair value. Financial Instruments Our financial assets are measured at fair value on a recurring basis using the following hierarchy to prioritize valuation inputs, in accordance with applicable GAAP: Level 1: Quoted prices in active markets for identical assets or liabilities that we have the ability to access Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data such as quoted prices, interest rates and yield curves Level 3: Inputs that are unobservable data points that are not corroborated by market data We review the fair value hierarchy classification on a quarterly basis. Changes in the ability to observe valuation inputs may result in a reclassification of levels of certain securities within the fair value hierarchy. We recognize transfers into and out of levels within the fair value hierarchy in the period in which the actual event or change in circumstances that caused the transfer occurs. There have been no transfers between Level 1, Level 2, and Level 3 in any periods presented. Financial assets and liabilities are considered Level 2 when their fair values are determined using inputs that are observable in the market or can be derived principally from or corroborated by observable market data such as pricing for similar securities, recently executed transactions, cash flow models with yield curves, and benchmark securities. In addition, Level 2 financial instruments are valued using comparisons to like-kind financial instruments and models that use readily observable market data as their basis. U.S. Treasury, government agency and corporate debt obligations, commercial paper and asset-backed securities are valued primarily using market prices of comparable securities, bid/ask quotes, interest rate yields and prepayment spreads and are included in Level 2. Financial assets and liabilities are considered Level 3 when their fair values are determined using pricing models, discounted cash flow methodologies, or similar techniques, and at least one significant model assumption or input is unobservable. We have no Level 3 financial assets or liabilities. Accounts Receivable, net Accounts receivable are recorded net of estimates of variable consideration for which reserves are established and which result from discounts and chargebacks that are offered within contracts between us and a limited number of specialty pharmacies and a specialty distributor in the United States. These reserves are classified as reductions of accounts receivable. We estimate the allowance for doubtful accounts using the current expected credit loss model, or CECL model. Under the CECL model, the allowance for doubtful accounts reflects the net amount expected to be collected from the accounts receivable. We evaluate the collectability of these cash flow based on the asset’s amortized cost, the risk of loss even when that risk is remote, losses over an asset’s contractual life, and other relevant information available to us. Accounts receivable balances are written off against the allowance when it is probable that the receivable will not be collected. Given the nature and history of our accounts receivable, we determined that an allowance for doubtful accounts was not required as of the periods presented. Inventories Inventories are stated at the lower of cost or estimated net realizable value, on a specific identification basis. We use actual costs to determine our cost basis for inventories. Inventories consist of raw materials, work-in-process and finished goods. Finished goods inventories in excess of one year of forecasted sales are classified in the Consolidated Balance Sheets as non-current “Other assets.” We begin capitalizing costs as inventory when the product candidate receives regulatory approval and when the manufacturing facility producing such inventory is qualified by the relevant regulatory agency. Prior to regulatory approval and qualification, we record such production costs related to product candidates as research and development expenses. Any manufactured product that is available for commercial sale is recorded to inventory; to the extent it is later used for clinical studies, such inventory costs are then recorded within research and development expenses. We periodically assess the recoverability of our inventory and reduce the carrying value of the inventory when items are determined to be obsolete, defective or in excess of forecasted sales requirements. Inventory write-downs for excess, defective and obsolete inventory are recorded as a cost of sales. There have been no write-downs of our inventories for the periods presented. Property and Equipment, net Property and equipment are stated at cost and depreciated using the straight-line method over the estimated useful lives of the assets, ranging from three to five years , except for leasehold improvements, which are depreciated on a straight-line basis over the lesser of the estimated useful life of the leasehold improvement or the lease term. Costs incurred to acquire, construct or install property and equipment during the construction stage of a capital project or costs incurred to purchase and develop internal use software during the application development stage are recorded as construction in progress. Maintenance and repairs are charged to operations as incurred. Long-lived Assets We evaluate the carrying amount of our long-lived assets whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of the asset and its eventual disposition are less than the carrying amount of the asset. To date, there have been no such impairment losses. Asset Retirement Obligation (“ARO”) An ARO is a legal obligation associated with the retirement of long-lived assets pertaining to leasehold improvements. These liabilities are initially recorded at fair value and the related asset retirement costs are capitalized by increasing the carrying amount of the related assets by the same amount as the liability. Asset retirement costs are subsequently depreciated over the useful lives of the related assets. Subsequent to initial recognition, the Company records period-to-period changes in the ARO liability resulting from the passage of time and revisions to either the timing or the amount of the original estimate of undiscounted cash flows. The Company derecognizes ARO liabilities when the related obligations are settled. Leases We determine if a contract is or contains a lease at contract inception. Operating leases are included in operating lease assets, other current liabilities, and operating lease liabilities on our consolidated balance sheets. Our policy is to not recognize right-of-use (“ROU”) assets and lease liabilities for short-term operating leases with terms of 12 months or less; we recognize short-term lease expense for these leases on a straight-line basis over the lease term. Long-term operating lease ROU assets and long-term operating lease liabilities are presented separately and operating lease liabilities payable in the next twelve months are recorded in other current liabilities. Finance lease ROU assets are recorded in other assets and the related finance lease liabilities are presented in other current liabilities and other long-term liabilities. Lease assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. The lease term includes renewal options that we are reasonably certain of exercising as of the commencement date. None of the lease terms used to calculate the future minimum lease payments at commencement date include renewal options. As most of our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of future payments. The incremental borrowing rate for our leases is determined based on lease term and currency in which lease payments are made, adjusted for impacts of collateral. Lease assets also includes any lease payments made and excludes lease incentives and initial direct costs incurred. Operating lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. Finance lease assets are amortized over the shorter of the lease term or the asset’s estimated useful life. Our facilities and equipment operating leases have lease and non-lease components and we have made a policy election to account for the lease and non-lease components as a single lease component. We are considered the sub-lessor for certain of our leases where we have entered into a sub-lease agreement with or have assigned our lease to another party. Rental income was not material for any period presented and we record rental income as a reduction to rent expense within operating expenses. Accruals of Research and Development Costs We record accruals for estimated research and development costs based on an evaluation of our vendors’ progress towards completion of specific tasks, using data such as patient enrollment, clinical site activations or information provided to us by our vendors regarding their actual costs incurred. Payments for these activities are based on the terms of individual contracts and payment timing may differ significantly from the period in which the services are performed. We determine accrual estimates through reports from and discussions with internal personnel and outside service providers as to the progress or state of completion of studies, or the services completed. Our estimates of accrued expenses as of each balance sheet date are based on the facts and circumstances known at the time. Costs that are paid in advance of performance are deferred as a prepaid expense and amortized over the period in which the services are provided. Sale of Future Revenues To the extent that we account for the sale of future revenues as debt in accordance with ASC 470, we amortize the liability and recognize interest expense related to the sale of future revenues using the effective interest rate method over the estimated life of the underlying agreement. The liability and related interest expense are based on our current estimate of expected future payments over the life of the arrangement. We will re-assess the amount and timing of expected payments each reporting period using a combination of internal projections and forecasts from external resources and record interest expense on the carrying value of the liability using the imputed effective interest rate on a prospective basis. Revenue Recognition For contracts that are determined to be within the scope of Accounting Standards Codification Topic 606 (Accounting Standards Update (“ASU”) No. 2014-09), Revenue from Contracts with Customers , and all subsequent amendments (collectively, “ASC 606”), revenue is recognized as we satisfy performance obligations and when a customer obtains control of the promised goods or services. The amount of revenue recognized reflects the consideration to which we expect to be entitled to receive in exchange for these goods and services. To achieve this core principle, we apply the following five steps (i) identify the contract with the customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when or as we satisfy a performance obligation. We only apply the five-step model to contracts when we determine that collection of substantially all consideration for goods and services that are transferred is probable based on the customer’s intent and ability to pay the promised consideration. Performance obligations promised in a contract are identified based on the goods and services that will be transferred to the customer that are both capable of being distinct and are distinct in the context of the contract. To the extent a contract includes multiple promised goods and services, we apply judgment to determine whether promised goods and services are both capable of being distinct and distinct in the context of the contract. If these criteria are not met, the promised goods and services are accounted for as a combined performance obligation. The transaction price is determined based on the consideration to which we will be entitled in exchange for transferring goods and services to the customer. To the extent the transaction price includes variable consideration, we estimate the amount of variable consideration that should be included in the transaction price utilizing either the expected value method or the most likely amount method, depending on the nature of the variable consideration. Variable consideration is included in the transaction price if, in our judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Any estimates, including the effect of the constraint on variable consideration, are evaluated at each reporting period for any changes. Determining the transaction price requires significant judgment, which is discussed in further detail for our out-license agreements in Note 5. Our out-license agreements do not contain a significant financing component. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation on a relative standalone selling price basis unless the transaction price is variable and meets the criteria to be allocated entirely to a performance obligation or to a distinct service that forms part of a single performance obligation. The consideration to be received is allocated among the separate performance obligations based on relative standalone selling prices. We typically determine standalone selling prices using an expected cost plus margin approach model. We satisfy performance obligations either over time or at a point in time. Revenue is recognized over time if either (i) the customer simultaneously receives and consumes the benefits provided by our performance, (ii) our performance creates or enhances an asset that the customer controls as the asset is created or enhanced or (iii) our performance does not create an asset with an alternative use to the entity and we have an enforceable right to payment for performance completed to date. We evaluate the measure of progress each reporting period and, if necessary, adjust the measure of performance and related revenue recognition. If we do not satisfy a performance obligation over time, the related performance obligation is satisfied at a point in time by transferring control of a promised good or service to a customer. As of December 31, 2022, our deferred revenue is related to the Pierre Fabre Commercialization Agreement, which is within the scope of ASC 606. As discussed in further detail in Note 5, the terms of these arrangements include potential payments to us for some or all of the following: nonrefundable, upfront fees; development, regulatory, and commercial milestone payments; research and development funding payments; and royalties on the net sales of licensed products. These payments relate to promised goods or services for which revenue will be recognized upon our satisfaction of the underlying performance obligations. Licenses of intellectual property : If the license of our intellectual property is determined to be distinct from the other performance obligations identified in an arrangement, we recognize revenues from consideration allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. For licenses that are combined with other promises, we utilize judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. Upfront payments : Upfront payments and fees are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until we have satisfied our obligations under these arrangements. Milestone payments : At the inception of each arrangement that includes development milestone payments, we evaluate the probability of reaching the milestones and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur in the future, the associated milestone value is included in the transaction price. The transaction price is then allocated to each performance obligation on a relative standalone selling price basis, for which we recognize revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, we re-evaluate the probability of achievement of such development milestones and any related constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and collaboration revenues and the consolidated statements of operations and comprehensive loss in the period of adjustment. Royalties : For arrangements that include sales-based royalties, including milestone payments based on levels of sales, if the license is deemed to be the predominant item to which the royalties relate, we recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied, or partially satisfied. To date, we have not recognized any royalty revenue resulting from our out-licensing agreements. Certain judgments affect the application of our revenue recognition policy. For example, we record short-term and long-term deferred revenue based on our best estimate of when such revenue will be recognized. Short-term deferred revenue consists of amounts that are expected to be recognized as revenue in the next 12 months, and long-term deferred revenue consists of amounts that we do not expect will be recognized in the next 12 months. This estimate is based on our forecasted patient demand and current operating plan and, if patient demand or our operating plan should change in the future, we may recognize a different amount of deferred revenue over the next 12-month period. Research and Development Expense Research and development expense consists of costs incurred in performing research and development activities, including compensation and benefits for research and development employees; expenses incurred under agreements with contract research organizations and investigative sites that conduct clinical and preclinical studies; expense incurred under agreements with contract manufacturing organizations related to acquiring and manufacturing clinical study materials and other supplies to support the manufacture of our product candidates; payments under licensing and research and development agreements; other outside services and consulting costs, and facilities, information technology and overhead expenses. Research and development costs are expensed as incurred. Stock-Based Compensation Expense We account for stock-based compensation expense, including the expense of restricted common stock awards (“RSAs”), grants of restricted stock units (“RSUs”), and stock options that may be settled in shares of our common stock, based on the fair values of the equity instruments issued. The fair value is determined on the measurement date, which is generally the date of grant. The fair value of our RSUs is measured at the closing market price of our common stock on the measurement date. The fair value for our stock option awards is determined at the grant date using the Black-Scholes valuation model. In determining the fair value of stock option awards granted, we use the Black-Scholes valuation model and assumptions include: Expected term – We derived the expected term using the “simplified” method (the expected term is determined as the average of the time-to-vesting and the contractual life of the options), as we have limited historical information to develop expectations about future exercise patterns and post vesting employment termination behavior. Expected volatility – Prior to 2021, expected volatility was estimated using comparable public companies’ volatility for similar terms. Beginning in 2021, volatility is estimated using an average of Atara’s historical volatility and comparable public companies’ volatility for similar terms. Expected dividend – We have not historically declared or paid dividends to our stockholders and have no plans to pay dividends; therefore, we assumed an expected dividend yield of 0 %. Risk-free interest rate – The risk-free interest rate is based on the yield on U.S. Treasury securities with the expected term of the associated award. For awards with performance-based vesting criteria, we assess the probability of the achievement of the performance conditions at the end of each reporting period and begin to recognize the share-based compensation costs when it becomes probable that the performance conditions will be met. For awards that are subject to both service and performance conditions, no expense is recognized until it is probable that performance conditions will be met. Stock-based compensation expense for awards with time-based vesting criteria is recognized as expense on a straight-line basis over the requisite service period. Stock-based compensation expense for awards with performance and other vesting criteria is recognized as expense under an accelerated graded vesting model. We account for forfeitures of stock-based awards as they occur. Defined Contribution Plan We have one qualified 401(k) plan covering all eligible employees. Under the plan, employees may contribute up to the statutory allowable amount for any calendar year. We make matching contributions, equal to 50 % of each dollar contributed up to the first 6 % of an individual’s eligible earnings, up to the annual IRS maximum. For the years ended December 31, 2022, 2021 , and 2020 we recorded matching contributions of approximately $ 2.3 million, $ 2.6 million, and $ 2.1 million, respectively. Income Taxes We use the asset and liability method to account for income taxes. We record deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial statement carrying amounts and the tax basis of assets and liabilities using enacted tax rates expected to be in effect when the differences are expected to reverse. Valuation allowances are provided when necessary to reduce net deferred tax assets to the amount that is more likely than not to be realized. Based on the available evidence, we are unable, at this time, to support the determination that it is more likely than not that our deferred tax assets will be utilized in the future. Accordingly, we recorded a full valuation allowance as of December 31, 2022 and 2021. We intend to maintain valuation allowances until sufficient evidence exists to support their reversal. Tax benefits related to uncertain tax positions are recognized when it is more likely than not that a tax position will be sustained during an audit. Interest and penalties related to unrecognized tax benefits are included within the provision for income tax. Comprehensive Income (Loss) Comprehensive income (loss) is defined as a change in equity of a business enterprise during a period resulting from transactions from non-owner sources. Our other comprehensive income (loss) is comprised solely of unrealized gains (losses) on available-for-sale securities and is presented net of taxes. There have not been any material reclassifications from other comprehensive income (loss) to net loss recorded during any period presented. Recent Accounting Pronouncements We consider the applicability and impact of any recent ASU issued by the Financial Accounting Standards Board (“FASB”). Based on our assessment, the ASUs were determined to be either not applicable or are expected to have minimal impact on our consolidated financial statements.

Net Loss per Common Share

Net Loss per Common Share	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Net Loss per Common Share	3. Net Loss per Common Share Basic net loss per common share is calculated by dividing net loss by the weighted-average number of shares of common stock and pre-funded warrants outstanding during the period, without consideration of common share equivalents. Diluted net loss per common share is computed by dividing net loss by the weighted-average number of shares of common stock, pre-funded warrants and common share equivalents outstanding for the period. The pre-funded warrants are included in the computation of basic and diluted net loss per common share as the exercise price is negligible and the pre-funded warrants are fully vested and exercisable. Common share equivalents are only included in the calculation of diluted net loss per common share when their effect is dilutive. Potential dilutive securities, which include unvested RSUs, unvested performance-based RSUs and performance-based options to purchase common stock for which established performance criteria have been achieved as of the end of the respective periods, vested and unvested options to purchase common stock and shares to be issued under our employee stock purchase plan (“ESPP”), have been excluded from the computation of diluted net loss per share as the effect is antidilutive. Therefore, the denominator used to calculate both basic and diluted net loss per common share is the same in all periods presented. The following table represents the potential common shares issuable pursuant to outstanding securities as of the dates listed that were excluded from the computation of diluted net loss per common share, as their inclusion would have an antidilutive effect: As of December 31, 2022 2021 2020 Unvested RSUs 6,698,858 5,253,347 2,868,407 Vested and unvested options 10,336,634 9,200,337 7,832,386 ESPP share purchase rights 86,782 27,238 26,349 Total 17,122,274 14,480,922 10,727,142

Financial Instruments

Financial Instruments	12 Months Ended
	Dec. 31, 2022
Financial Instruments Disclosure [Abstract]
Financial Instruments	4. Financial Instruments The following tables summarize the estimated fair value and related valuation input hierarchy of our available-for-sale securities as of each period end: Total Total Total Total Amortized Unrealized Unrealized Estimated As of December 31, 2022: Input Level Cost Gain Loss Fair Value (in thousands) Money market funds Level 1 $ 78,033 $ — $ — $ 78,033 U.S. Treasury obligations Level 2 63,013 3 ( 394 ) 62,622 Government agency obligations Level 2 8,086 — ( 48 ) 8,038 Corporate debt obligations Level 2 82,598 4 ( 1,513 ) 81,089 Commercial paper Level 2 996 — — 996 Asset-backed securities Level 2 6,343 — ( 119 ) 6,224 Total available-for-sale securities 239,069 7 ( 2,074 ) 237,002 Less: amounts classified as cash equivalents ( 87,122 ) ( 3 ) — ( 87,125 ) Amounts classified as short-term investments $ 151,947 $ 4 $ ( 2,074 ) $ 149,877 Total Total Total Total Amortized Unrealized Unrealized Estimated As of December 31, 2021: Input Level Cost Gain Loss Fair Value (in thousands) Money market funds Level 1 $ 89,738 $ — $ — $ 89,738 U.S. Treasury obligations Level 2 111,832 1 ( 138 ) 111,695 Government agency obligations Level 2 21,346 — ( 23 ) 21,323 Corporate debt obligations Level 2 99,757 6 ( 190 ) 99,573 Commercial paper Level 2 36,993 — — 36,993 Asset-backed securities Level 2 10,174 1 ( 25 ) 10,150 Total available-for-sale securities 369,840 8 ( 376 ) 369,472 Less: amounts classified as cash equivalents ( 104,488 ) — — ( 104,488 ) Amounts classified as short-term investments $ 265,352 $ 8 $ ( 376 ) $ 264,984 The amortized cost and fair value of our available-for-sale securities by contractual maturity were as follows: As of December 31, 2022 As of December 31, 2021 Amortized Estimated Amortized Estimated Cost Fair Value Cost Fair Value (in thousands) (in thousands) Maturing within one year $ 202,323 $ 201,359 $ 278,457 $ 278,354 Maturing in one to five years 36,746 35,643 91,383 91,118 Total available-for-sale securities $ 239,069 $ 237,002 $ 369,840 $ 369,472 We considered the current and expected future global economic and market conditions, including the COVID-19 pandemic and the war in Ukraine, and determined that our investments have not been significantly impacted. As of December 31, 2022, no significant facts or circumstances were present to indicate a deterioration in the creditworthiness of the issuers of the available-for-sale securities we hold, and we have no requirement or intention to sell these securities before maturity or recovery of their amortized cost basis. For all securities with a fair value less than its amortized cost basis, we determined the decline in fair value below amortized cost basis to be non-credit related and no allowance for losses has been recorded. During the years ended December 31, 2022, 2021 and 2020, we did not recognize any impairment losses on our investments. We have elected the practical expedient to exclude the applicable accrued interest from both the fair value and the amortized cost basis of our available-for-sale securities for purposes of identifying and measuring an impairment. We present accrued interest receivable related to our available-for-sale securities in other current assets, separate from short-term investments on our consolidated balance sheet. As of December 31, 2022 and 2021 , accrued interest receivable was $ 0.8 million and $ 0.8 million, respectively. Our accounting policy is to not measure an allowance for credit losses for accrued interest receivables and to write-off any uncollectible accrued interest receivable as a reversal of interest income in a timely manner, which we consider to be in the period in which we determine the accrued interest will not be collected by us. We have no t written off any accrued interest receivables for the years ended December 31, 2022, 2021 and 2020. In addition, restricted cash collateralized by money market funds is a financial asset measured at fair value and is a Level 1 financial instrument under the fair value hierarchy. The following table provides a reconciliation of cash, cash equivalents and restricted cash within the consolidated balance sheets that sum to the total of the same such amounts in the consolidated statement of cash flows: December 31, December 31, 2022 2021 (in thousands) Cash and cash equivalents $ 92,942 $ 106,084 Restricted cash - short-term 146 194 Restricted cash - long-term — 1,200 Total cash, cash equivalents and restricted cash $ 93,088 $ 107,478

Out-license Agreements

Out-license Agreements	12 Months Ended
	Dec. 31, 2022
Research and Development [Abstract]
Out-license Agreements	5. Out- license Agreements Pierre Fabre Commercialization Agreement In October 2021, we entered into the Pierre Fabre Commercialization Agreement, pursuant to which, we granted to Pierre Fabre an exclusive, field-limited license to commercialize and distribute Ebvallo in Europe and select emerging markets in the Territory following regulatory approval. Atara retains full rights to Ebvallo in other major markets, including North America, Asia Pacific and Latin America. In September 2022, we entered into Amendment No. 1 to the Pierre Fabre Commercialization Agreement (the “PF Amendment”). Under the terms of the PF Amendment, following European Commission approval of Ebvallo for EBV+ PTLD and subsequent filing of the Marketing Authorization Application (“MAA”) transfer to Pierre Fabre, we are entitled to receive an additional $ 30 million milestone payment in exchange for, among other things, a reduction in: (i) royalties we are eligible to receive as a percentage of net sales of Ebvallo in the Territory, and (ii) the supply price mark up on Ebvallo purchased by Pierre Fabre. Additionally, we also agreed to extend the time period for provision of certain services to Pierre Fabre under the Pierre Fabre Commercialization Agreement. We are responsible at our cost for the conclusion of the ongoing Phase 3 ALLELE clinical study and the Phase 2 multi-cohort clinical study. We will also be responsible at our cost for certain other activities directed to obtaining regulatory approval for Ebvallo for EBV-positive lymphoproliferative disease pursuant to the terms of the Pierre Fabre Commercialization Agreement in Europe. Pierre Fabre will be responsible at its cost for obtaining and maintaining all other regulatory approvals and for commercialization and distribution of Ebvallo in the Territory. We will own any intellectual property rights developed solely by us under the Agreement. Pierre Fabre paid us an upfront cash payment of $ 45.0 million for the exclusive license grant in the fourth quarter of 2021. In December 2022, we met the contractual right to receive $ 40.0 million in milestone payments upon certain regulatory milestones. Subject to the terms of the royalty purchase agreement with HCRx, as described in Note 6, we are entitled to receive an aggregate of up to $ 308.0 million in remaining milestone payments upon achieving certain regulatory and commercial milestones in addition to double-digit tiered royalties as a percentage of net sales of Ebvallo, until the later of 12 years after the first commercial sale in such country, the expiration of specified patent rights, or the expiration of all regulatory exclusivity for such product on a country-by-country basis. We have entered into a separate manufacturing and supply agreement with Pierre Fabre for us to manufacture Ebvallo for Pierre Fabre to use in the Territory based on a fixed price through December 31, 2023 and cost plus a margin post January 1, 2024. We are responsible for manufacturing and supplying Pierre Fabre with Ebvallo for commercialization in the Territory at Pierre Fabre’s cost for a minimum of seven years from the first commercial sale, as defined in the Pierre Fabre Commercialization Agreement, of Ebvallo in the Territory. Following this period, we have the option to transfer the manufacturing responsibility and related manufacturing technology to a third party contract manufacturing organization (“CMO”), and Pierre Fabre may also elect to directly assume the manufacturing responsibility and receive the related manufacturing technology. We are also responsible for cell selection services at our cost for a certain period of time unless the parties agree to transfer the related cell selection technology to Pierre Fabre prior to this date. After this period of time, if we agree to continue to provide cell selection services, it shall be at the sole expense of Pierre Fabre. We have formed a joint steering committee with Pierre Fabre that provides oversight, decision making and implementation guidance regarding the commercialization activities covered under the agreement. We assessed this arrangement in accordance with ASC 606 and concluded that the promises in the Pierre Fabre Commercialization Agreement represent transactions with a customer. We concluded that the Pierre Fabre Commercialization Agreement includes transfer of intellectual property rights in the form of a license, the potential to manufacture and supply Ebvallo for a minimum of seven years and until tech transfer, the potential to perform cell-selection services for a minimum of three years and until tech transfer, and obligation to participate in the JSC. We concluded that the promises are not distinct because Pierre Fabre cannot benefit from the license without the other services and vice versa. Consequently, the license, manufacture and supply, cell selection and participation in the JSC is a single performance obligation. Under the Pierre Fabre Commercialization Agreement, we determined that the $ 45.0 million upfront payment, constituted the entire consideration to be included in the transaction price at the outset of the arrangement. The $ 40.0 million in development milestones met in December 2022 were added to the transaction price upon meeting of the related milestones. Revenue associated with the upfront fee and development milestones for the single performance obligation will be deferred until the initial delivery of services related to the manufacture and supply and cell selection and then recognized over the period during which Pierre Fabre’s material right to these services exists. The $ 85.0 million in upfront fee and milestones met is recorded as deferred revenue as of December 31, 2022, of which $ 8.0 million is included in current liabilities and $ 77.0 million is included in long-term liabilities, and we expect to recognize this revenue over the next 12 years. The remaining potential development and commercial milestone payments that we are eligible to receive were excluded from the transaction price, as the milestone amounts were fully constrained based on the probability of achievement or have not been earned. None of the future royalty and sales-based milestone payments were included in the transaction price, as the potential payments represent sales-based consideration. We will reevaluate the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjust our estimate of the transaction price. Bayer Agreements Research, Development and License Agreement In December 2020, we entered into the Bayer License Agreement to develop mesothelin-directed CAR T-cell therapies for the treatment of solid tumors, pursuant to which we granted to Bayer an exclusive, field-limited license under the applicable patents and know-how owned or controlled by us and our affiliates covering or related to ATA2271 and ATA3271 (the “Licensed Products”). Under the terms of the Bayer License Agreement, we were responsible at our cost for all mutually agreed preclinical and clinical activities for ATA2271 through the first in human Phase 1 clinical study in collaboration with MSK, following which Bayer was responsible for the further development of ATA2271 at its cost. Bayer was responsible for the development of ATA3271, except for certain mutually agreed preclinical, translational, manufacturing and supply chain activities to be performed by us relating to ATA3271, in each case at Bayer’s cost. Bayer was also be solely responsible for commercializing the Licensed Products at its cost. In December 2020, we received an upfront cash payment of $ 45.0 million from Bayer for the exclusive license grant, net of applicable withholding taxes, which were fully recovered in August 2021, and an additional $ 15.0 million upfront reimbursement payment for certain research and process development activities to be performed by us. The transaction price at inception consisted of a $ 45.0 million upfront payment for the license, $ 15.0 million for certain research and process development activities and the $ 5.0 million for additional specified translational activities, and this amount was allocated to the single performance obligation. The potential development and commercial milestone payments that we are eligible to receive were excluded from the transaction price, as all milestone amounts were fully constrained based on the probability of achievement. None of the future royalty and sales-based milestone payments were included in the transaction price, as the potential payments represent sales-based consideration. We reevaluated the transaction price at the end of each reporting period and as uncertain events are resolved or other changes in circumstances occur, and, if necessary, adjust our estimate of the transaction price. Technology Transfer Agreement In March 2021, we entered into a Technology Transfer Agreement with Bayer (the “Bayer Tech Transfer Agreement”), which was contemplated as part of the Bayer License Agreement, to transfer to Bayer the ATA3271 manufacturing process being developed as part of the CMC services in the Bayer License Agreement. Upon entering into the agreement, we invoiced Bayer 20 percent of the total fee of $ 15.3 million under the Bayer Tech Transfer Agreement, or $ 3.1 million, which we received in the second quarter of 2021 and invoiced 40 percent of the total fee, or $ 6.1 million, in the first quarter of 2022. We assessed this arrangement in accordance with ASC 606 and concluded that the promises in the Bayer Tech Transfer Agreement represent transactions with a customer. We concluded that the Bayer Tech Transfer Agreement should be combined with the Bayer License Agreement and accounted for as a modification of that agreement and that the Bayer Tech Transfer Agreement contains the following promises: (i) technology transfer services and (ii) supply of materials required for the technology transfer services. In accordance with ASC 606, we determined that the technology transfer services and supply of materials required for the technology transfer services were not distinct from each other, as they are highly interdependent upon one another. In addition, we concluded that the technology transfer services and supply of materials required for the technology transfer services were highly interdependent with the license, early-stage R&D and CMC services identified in the Bayer License Agreement. Accordingly, we determined that these promises should be combined into a single performance obligation. Under the Bayer Tech Transfer Agreement, in order to evaluate the appropriate transaction price, we determined that the $ 15.3 million fee constituted the entire consideration to be included in the transaction price, and this amount was allocated to the single performance obligation as identified under the Bayer License Agreement. We utilize a cost-based input method to recognize revenue based on the amount of actual costs incurred relative to the total budgeted costs expected to be incurred for the combined performance obligation. Manufacturing and Supply Agreement In March 2021, we entered into a Manufacturing and Supply Agreement with Bayer (the “Bayer Manufacturing Agreement”), which was contemplated as part of the Bayer License Agreement, to manufacture Phase 1 and 2 allogeneic mesothelin-directed CAR T-cell therapies for Bayer to use in clinical trials at a price based on our costs plus a reasonable margin, which is consistent with our standalone selling price. Under the Bayer Manufacturing Agreement, we will also provide storage and distribution services to Bayer at a price that is consistent with our standalone selling price for these services. Upon entering into the Bayer Manufacturing Agreement, Bayer submitted, and we approved, a binding purchase order for manufacturing services and storage services. Any fees for the manufacturing services will be invoiced as follows: (i) 50 percent upon written acceptance by us of the binding purchase order, and (ii) the remainder upon delivery of the certification of analysis of such lots to Bayer. Storage and distribution services are billed monthly as those services are provided to Bayer. In March 2021, we invoiced Bayer 50 percent of the total estimated supply price of $ 13.1 million for manufacturing services under the initial purchase order for the supply of six lots, or $ 6.6 million, which we received in the second quarter of 2021. The remainder of the supply price will be billed upon the release of the lots ordered by Bayer. We assessed this arrangement in accordance with ASC 606 and concluded that the promises in the manufacturing and supply agreement represent transactions with a customer. We concluded that the Bayer Manufacturing Agreement contains the following promises: (i) manufacturing services; (ii) storage services provided on a month-to-month basis; and (iii) distribution services. In accordance with ASC 606, we determined that the manufacturing services for the initial purchase order of six lots, that are expected to be provided prior to completion of the technology transfer, are not distinct as they are highly interdependent on the manufacturing process being developed and transferred under the Bayer License Agreement and the Bayer Tech Transfer Agreement. Accordingly, we determined that these promises should be combined into a single performance obligation. We also determined that each of the other services were distinct and separate performance obligations. We determined that the initial binding order for the manufacture and supply of six lots should be combined with the Bayer License Agreement and accounted for as a modification of that agreement along with the Bayer Tech Transfer Agreement. We also concluded that a binding purchase order from Bayer, together with the Bayer Manufacturing Agreement, form the contract for manufacturing services and storage services and a shipping order from Bayer forms the contract for distribution services. We also determined that the storage services provided on a month-to-month basis and distribution services are distinct and separate performance obligations. All the performance obligations identified above are priced at their standalone selling price. Under the Bayer Manufacturing Agreement, in order to evaluate the appropriate transaction price, we determined that the $ 13.1 million fee constituted the entire consideration to be included in the transaction price, and this amount was allocated to the single performance obligation as identified under the Bayer License Agreement. Revenue for the manufacturing services for the initial six lots will be recognized based on the amount of actual costs incurred relative to the total budgeted costs expected to be incurred for the combined performance obligation. Revenue for the storage services will be recognized over time as those services are provided. Revenue for the distribution services will be recognized at a point in time when the product is delivered to a clinical site designated by Bayer. Bayer Agreements Termination and Revenue Recognition In May 2022, Bayer notified us of its decision to terminate the Bayer Agreements, and on August 2, 2022, we entered into the Bayer Termination Agreement with an effective date of July 31, 2022. Upon the termination effective date, full product development rights related to ATA2271 and ATA3271 reverted to Atara. In return for certain activities performed by Atara prior to the termination effective date, Bayer paid Atara $ 4.2 million in September 2022. Utilizing the cost-based input method, we recognized license and collaboration revenue of $ 61.8 million for the year ended December 31, 2022, under the Bayer Agreements and Bayer Termination Agreement. For the year ended December 31, 2021, we recognized license and collaboration revenue of $ 19.8 million under the Bayer Agreements. There was no deferred revenue related to the Bayer Agreements as of December 31, 2022, compared to $ 51.5 million as of December 31, 2021. No development or sales-based milestone payments have been earned or received.

Liability Related to the Sale o

Liability Related to the Sale of Future Royalties	12 Months Ended
	Dec. 31, 2022
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Liability Related to the Sale of Future Royalties [Text Block]	6. Liability Related to the Sale of Future Revenues In December 2022, we entered into a Purchase and Sale Agreement (the “HCRx Agreement”) with HCR Molag Fund, L.P., a Delaware limited partnership, (“HCRx”). In exchange for a payment of $ 31.0 million (the “Investment Amount”), net of certain transaction expenses, to Atara, HCRx obtained the right to receive certain Ebvallo royalties and milestone payments payable by Pierre Fabre under the Pierre Fabre Commercialization Agreement up to an agreed upon multiple of the Investment Amount. We received the Investment Amount, net of certain transaction costs, from HCRx on December 30, 2022. Under the HCRx Agreement, HCRx is entitled to receive tiered royalties on net sales of Ebvallo in the Territory (as defined in the Pierre Fabre Commercialization Agreement) in amounts ranging from the mid-single digits to double digits based on annual net sales. HCRx is also entitled to certain milestone payments due to Atara from Pierre Fabre. The total royalties and milestones payable to HCRx are capped between 185 % and 250 % of the Investment Amount, depending upon the timing of such royalties and milestones. Upon meeting the cap amount, HCRx’s right to receive royalties and milestone payments will terminate and all rights will revert to Atara. To the extent a certain milestone within the Pierre Fabre Commercialization Agreement is not achieved on or prior to June 30, 2026, we will be required to make a one-time cash payment in the amount of $ 9.0 million to HCRx, and HCRx shall transfer all of its right, title and interest in this certain $ 9.0 million milestone payment to Atara. This payment, if required, would be included in the calculation of aggregate payments made to HCRx. The gross proceeds of the Investment Amount of $ 31.0 million were recorded as a liability related to the sale of future revenues, net of transaction costs of $ 0.4 million, and will be amortized using the effective interest method over the life of the arrangement. To determine the amortization of the recorded liability, we are required to estimate the total amount of future payments to be received by HCRx. The sum of these amounts less the $ 31.0 million proceeds we received will be recorded as interest expense over the life of the HCRx Agreement. We will estimate the effective interest rate used to record non-cash interest expense under the HCRx Agreement based on the estimate of future royalty payments to be received by HCRx. Over the life of the arrangement, the actual effective interest rate will be affected by the amount and timing of the royalty and milestone payments received by HCRx and changes in our forecasted payments to HCRx. At each reporting date, we will reassess our estimate of total future royalty payments to be received by HCRx, and prospectively adjust the effective interest rate and amortization of the liability as necessary. The following table presents the changes in the liability related to the sale of future revenues under the HCRx Agreement for the year ended December 31, 2022 : For the year ended December 31, 2022 (in thousands) Liability related to the sale of future revenues, beginning balance $ — Proceeds from sale of future revenues, net 30,605 Less: debt issuance costs ( 368 ) Liability related to the sale of future revenues, ending balance $ 30,237

Sale of ATOM Facility

Sale of ATOM Facility	12 Months Ended
	Dec. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
Sale of ATOM Facility	7. Sale of ATOM Facility On April 4, 2022, we completed the sale of the ATOM Facility to FDB for net proceeds of $ 94.8 million, after deducting transaction costs of $ 4.6 million and other adjustments to the purchase price. The sale resulted in a gain of $ 50.2 million included within other income (expense), net for the year end December 31, 2022. As disclosed in Note 8, although we have assigned the lease for the ATOM Facility to FDB, we have not received novation from the landlord. Therefore, the lease-related assets and liabilities for the ATOM Facility remain on our balance sheet. Refer to the summary of assets sold and gain on sale of the ATOM Facility: (in thousands) Net proceeds from sale of ATOM Facility $ 94,765 Assets sold: Other current assets $ 190 Property and equipment, net 44,299 Other assets 39 Less: Assets sold 44,528 Gain on sale of ATOM Facility $ 50,237 In connection with the sale, we entered into a Transition Services Agreement (“TSA”) with FDB, pursuant to which we are assisting them in the transition of certain functions, including, but not limited to, information technology, finance and technical operations. FDB will reimburse us at cost for all third party expenses incurred in conjunction with the TSA and for time incurred by our employees to satisfy requirements set forth by the TSA. The reimbursements are recorded as reductions to the related Operating expenses and the amounts associated with reimbursements for employee time incurred were not material for the year ended December 31, 2022. Any amounts owed to us by FDB under the TSA as of December 31, 2022 are included in other current assets.

Leases

Leases	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Leases	8. Leases We lease office space in South San Francisco, California under a non-cancellable lease agreement. In December 2021, we entered into a second amendment with the landlord to extend the lease term through May 2025 . The amended lease agreement does not include an option to extend the lease term. In connection with the amended lease, we are required to maintain a letter of credit in the amount of $ 0.1 million to the landlord. In October 2022, we entered into a sub-lease agreement with a third party for this office space. The sub-lease term commenced in November 2022 and expires in May 2025, with no option to extend the sub-lease term. Subsequently, we have moved our corporate headquarters to our office space in Thousand Oaks, California. In November 2018, we entered into a lease agreement for this office space that expires in February 2026 and for which we have the option to extend the lease for an additional period of five years after the initial term. In March 2021, we entered into a new lease agreement for approximately 33,659 square feet of office, lab and warehouse space in Thousand Oaks, California. During the third quarter of 2021, the initial 10.5 -year lease term commenced, upon substantial completion of the landlord’s work as defined under the agreement. Base rent is subject to annual increases of 3 % with each annual anniversary of the rent commencement date. We have the option to extend this lease for two additional five-year periods after the initial term. Additionally, in 2021, we entered into an amended lease agreement for our office and lab space in Aurora, Colorado, to add additional lab space. In February 2017, we entered into a lease agreement (the “ATOM Lease”) for approximately 90,580 square feet of office, lab and cellular therapy manufacturing space in Thousand Oaks, California. The initial 15-year term of the lease commenced on February 15, 2018 , upon the substantial completion of landlord’s work as defined under the agreement. In April 2022, we assigned the ATOM Lease to FDB in connection with the closing of the sale of the ATOM Facility to FDB. Under ASC 842, we are considered to be the sub-lessor of the ATOM Lease. We evaluated our vendor contracts to identify embedded leases and determined that the Fujifilm MSA contained items that constituted a lease under ASC 842, Leases, as Atara has the right to substantially all of the economic benefits from the use of the asset and can direct the use of the asset. We concluded that the Fujifilm MSA contains an embedded operating lease for certain dedicated processing rooms for the manufacturing of Atara product and an embedded finance lease for certain freezers dedicated for Atara’s use. The Fujifilm MSA includes contractual obligations in the form of payments for the processing rooms and the freezers, each over a term of five years . The maturities of lease liabilities under our operating and finance leases as of December 31, 2022 were as follows: Operating Leases Finance Leases Years Ending December 31, (in thousands) 2023 $ 19,158 $ 1,339 2024 18,035 1,242 2025 17,880 1,263 2026 16,557 1,285 2027 5,631 436 Thereafter 15,778 — Total lease payments $ 93,039 $ 5,565 Less: amount representing interest ( 22,169 ) ( 1,088 ) Present value of lease liabilities $ 70,870 $ 4,477 Balance as of December 31, 2022 Other current liabilities $ 12,806 $ 834 Operating lease liabilities - long-term 58,064 — Other long-term liabilities — 3,643 Total $ 70,870 $ 4,477 The components of lease cost were as follows: Year Ended Year Ended Year Ended December 31, 2022 December 31, 2021 December 31, 2020 (in thousands) Operating lease cost: Operating lease cost $ 14,245 $ 3,827 $ 3,020 Short-term lease cost 386 836 987 Total operating lease cost $ 14,631 $ 4,663 $ 4,007 Finance lease cost: Amortization expense $ 872 $ 244 $ 389 Interest on lease liabilities 373 29 60 Total finance lease cost $ 1,245 $ 273 $ 449 Other information related to leases was as follows: Year Ended Year Ended Year Ended December 31, 2022 December 31, 2021 December 31, 2020 (in thousands, except lease term and discount rate) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of Operating cash flows for operating leases $ 13,417 $ 3,738 $ 2,878 Operating cash flows for finance leases 335 32 62 Financing cash flows for finance leases 518 254 389 Operating lease assets obtained in exchange for lease obligations: $ 50,779 $ 13,427 $ — Finance lease assets obtained in exchange for lease obligations: 4,795 — 281 Non-cash increase to operating lease assets due to — 1,760 639 Weighted Average Remaining Lease Term Operating leases 5.9 years 9.2 years 9.4 years Finance leases 4.2 years 1.0 years 1.7 years Weighted Average Discount Rate Operating leases 9.9 % 9.6 % 10.3 % Finance leases 10.4 % 9.7 % 9.7 % Asset Retirement Obligation Our asset retirement obligation (“ARO”) consists of a contractual requirement to remove the tenant improvements at the ATOM Facility in Thousand Oaks, California and restore the facility to a condition specified in the lease agreement. Although we assigned the ATOM Lease to FDB in connection with the closing of the sale of the ATOM Facility to FDB in April 2022, we have not received novation from the landlord. Therefore, the ARO associated with the ATOM Facility remains on our balance sheet. We recorded an estimate of the fair value of our ARO liability in other long-term liabilities and the ARO asset as a long-term asset in the period incurred. The fair value of the ARO asset is amortized over the lease term. The fair value of our ARO was estimated by discounting projected cash flows over the estimated life of the related assets using our credit adjusted risk-free rate. As of December 31, 2022 and December 31, 2021, the ARO asset and liability were not material.

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2022
Restructuring and Related Activities [Abstract]
Restructuring	9. Restructuring On August 8, 2022, we announced a strategic reduction in workforce of approximately 20 % to focus our activities as an organization centered on research and development. The workforce reduction is expected to include total restructuring charges of $ 6.0 million, comprised primarily of severance payments, wages for the 60-day notice period in accordance with the California Worker Adjustment and Retraining Notification Act and continuing health care coverage for a period of time after separation. In most cases, the severance payments were paid as a lump sum in October 2022. Certain of the notified employees had employment agreements which provided for separation benefits in the form of salary continuation; these benefits will be paid between October 2022 and November 2023. All of the costs are cash expenditures and primarily represent one-time termination benefits. We recorded the following restructuring charges associated with the reduction in force: Year Ended December 31, 2022 (in thousands) Research and development expense $ 2,544 General and administrative expense 3,420 Total restructuring charges $ 5,964 The following restructuring liability activity was recorded in connection with the reduction in force for the year ended December 31, 2022, with all of the $ 1.5 million liability balance as of December 31, 2022 included within other current liabilities on the accompanying consolidated balance sheet: Total Restructuring Charges (in thousands) Liability balance, January 1, 2022 $ — Charges 5,964 Cash payments ( 4,419 ) Liability balance, December 31, 2022 $ 1,545

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	10. Commitments and Contingencies MSK Agreements In June 2015, we entered into an exclusive license agreement with MSK for three clinical stage T-cell therapies. We are required to make payments to MSK based on achievement of specified regulatory and sales-related milestones, as well as mid-single-digit percentage tiered royalty payments based on future sales of products resulting from the development of the licensed product candidates, if any. In addition, under certain circumstances, we are required to make certain minimum annual royalty payments to MSK, which are creditable against earned royalties owed for the same annual period. We are also required to pay a low double-digit percentage of any consideration we receive for sublicensing the licensed rights. The license agreement expires on a product-by-product and country-by-country basis on the latest of: (i) expiration of the last licensed patent rights related to each licensed product, (ii) expiration of any market exclusivity period granted by law with respect to each licensed product, and (iii) a specified number of years after the first commercial sale of the licensed product in each country. Upon expiration of the license agreement, Atara will retain non-exclusive rights to the licensed products. In May and December 2018, we licensed additional technology from MSK. We are obligated to make additional milestone payments based on achievement of specified development, regulatory and sales-related milestones as well as mid-single-digit percentage tiered royalty payments based on future sales of products resulting from the development of the licensed product candidates, if any. In March 2021, we amended and restated our license agreement with MSK to terminate our license to certain rights and license additional know-how rights not otherwise covered by our existing agreements. QIMR Berghofer Agreements In October 2015, we entered into an exclusive license agreement and a research and development collaboration agreement with QIMR Berghofer. Under the terms of the license agreement, we obtained an exclusive, worldwide license to develop and commercialize allogeneic T-cell therapy programs utilizing technology and know-how developed by QIMR Berghofer. In September 19 2016, the exclusive license agreement and research and development collaboration agreement were amended and restated. Under the amended and restated agreements, we obtained an exclusive, worldwide license to develop and commercialize additional T-cell programs, as well as the option to license additional technology that we exercised in June 2018. We further amended and restated our license agreement and research and development collaboration agreements with QIMR Berghofer in August 2019 to terminate our license to certain rights. Our current license agreement also provides for various milestone and royalty payments to QIMR Berghofer based on future product sales, if any. Under the terms of our current research and development collaboration agreement, we are also required to reimburse the cost of agreed-upon development activities related to programs developed under the collaboration. These payments are expensed on a straight-line basis over the related development periods. The agreement also provides for various milestone payments to QIMR Berghofer based on achievement of certain developmental and regulatory milestones. Other In-license and Collaboration Agreements From time to time, we have entered into other license and collaboration agreements with other parties. For example, we licensed rights related to our next-generation CAR T programs from Moffitt Cancer Center in August 2018, and we agreed to collaborate through sponsored research in connection with each of these licenses. We also licensed rights related to our MSK-partnered next-generation CAR T programs from the National Institutes of Health in December 2018. Milestones and royalties under each of the above agreements are contingent upon future events and will be recorded as expense when the underlying milestones are achieved or royalties are earned. As of December 31, 2022 and 2021, there were no material outstanding obligations for milestones and royalties under our in-license and collaboration agreements. CRL Manufacturing Agreement In December 2019, we entered into a Commercial Manufacturing Services Agreement (the “CRL MSA”) with Cognate BioServices, Inc., which was acquired by Charles River Laboratories Inc. (“CRL”) in March 2021. Pursuant to the CRL MSA, CRL provides manufacturing services for our product and certain of our product candidates. In February 2023, we amended the CRL MSA to extend the term until the earlier of September 30, 2023 or receipt of certain batches of our product and product candidates. Fujifilm Master Services and Supply Agreement In January 2022, we entered into the Fujifilm MSA, which became effective upon the closing of the sale of the ATOM Facility on April 4, 2022 and could extend for up to ten years . Pursuant to the Fujifilm MSA, FDB will supply us with specified quantities of our cell therapy products and product candidates, manufactured in accordance with cGMP standards. We have certain non-cancellable minimum commitments to purchase products and services over the first five years of the Fujifilm MSA. The Fujifilm MSA does not obligate us to purchase products and product candidates exclusively from FDB. Other Research, Development and Manufacturing Agreements We may enter into other contracts in the normal course of business with clinical research organizations for clinical trials, with CMOs for clinical supplies, and with other vendors for preclinical studies, supplies and other services for our operating purposes. These contracts generally provide for termination on notice. As of December 31, 2022 and December 31, 2021, there were no material amounts accrued related to contract termination charges. Based on our expectations of patients and demand for product in the EU, we believe our current inventory of Ebvallo is sufficient to supply commercial demand in the EU until the end of 2023. Minimum Commitments The non-cancellable minimum commitments for products and services, subject to agreements with a term of greater than one year with clinical research organizations and CMOs, excluding those recognized on our balance sheet, as of December 31, 2022 are set forth below: Calendar Year Remaining Minimum Commitment as of December 31, 2022 (in thousands) 2023 $ 19,420 2024 14,085 2025 13,308 2026 9,605 2027 3,388 Total $ 59,806 We have incurred $ 14.2 million against such minimum commitments for the year ended December 31, 2022. No such amounts were recorded for the years ended December 31, 2021 and 2020. As of December 31, 2022, we have accrued approximately $ 9.2 million in research and development expenses related to minimum purchase commitments. As of December 31, 2021, no such amounts were accrued. Indemnification Agreements In the normal course of business, we enter into contracts and agreements that contain a variety of representations and warranties and provide for indemnification for certain liabilities. The exposure under these agreements is unknown because it involves claims that may be made against us in the future but have not yet been made. To date, we have not paid any claims or been required to defend any action related to our indemnification obligations. However, we may record charges in the future as a result of these indemnification obligations. We also have indemnification obligations to our directors and executive officers for specified events or occurrences, subject to some limits, while they are serving at our request in such capacities. There have been no claims to date and we consider the fair value of these indemnification agreements to be minimal. Accordingly, we did no t record liabilities for these agreements as of December 31, 2022 and 2021. Contingencies From time to time, we may be involved in legal proceedings, as well as demands, claims and threatened litigation, which arise in the normal course of our business or otherwise. The ultimate outcome of any litigation is uncertain and unfavorable outcomes could have a negative impact on our results of operations and financial condition. Regardless of outcome, litigation can have an adverse impact on us because of the defense costs, diversion of management resources and other factors. We are not currently involved in any material legal proceedings.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Stockholders' Equity	11. Stockholders’ Equity Our authorized capital stock consists of 520,000,000 shares, all with a par value of $ 0.0001 per share, of which 500,000,000 shares are designated as common stock and 20,000,000 shares are designated as preferred stock. There were no shares of preferred stock outstanding as of December 31, 2022 and 2021. Equity Offerings As part of our July 2019 underwritten public offering, we issued and sold pre-funded warrants to purchase 2,945,026 shares of common stock in an underwritten public offering pursuant to a shelf registration on Form S-3. Each pre-funded warrant entitles the holder to purchase one share of common stock at an exercise price of $ 0.0001 per share and expires seven years from the date of issuance. These warrants were recorded as a component of stockholders’ equity within additional paid-in capital. Per the terms of the warrant agreement, a holder of the outstanding warrants is not entitled to exercise any portion of any pre-funded warrant if, upon exercise of the warrant, the holder’s ownership (together with its affiliates) of our common stock or combined voting power of our securities beneficially owned by such holder (together with its affiliates) would exceed 9.99 % after giving effect to the exercise (“Maximum Ownership Percentage”). Upon at least 61 days’ prior notice to us by the holder, any holder may increase or decrease the Maximum Ownership Percentage to any other percentage not to exceed 19.99 %. As of December 31, 2022, pre-funded warrants to purchase 2,888,526 shares of our common stock from the July 2019 offering were outstanding. In the second quarter of 2020, we issued and sold 12,633,039 shares of common stock at a public offering price of $ 11.32 per share and pre-funded warrants to purchase 2,866,961 shares of common stock at a public offering price of $ 11.3199 per warrant in an underwritten public offering pursuant to a shelf registration on Form S-3. We granted the underwriters an option to purchase up to 2,325,000 additional shares of our common stock at a public offering price of $ 11.32 , less underwriting discounts and commissions. The full option was exercised by the underwriters in June 2020. The gross proceeds from this public offering were $ 201.8 million, resulting in net proceeds of $ 189.3 million, after deducting underwriting discounts and commissions and offering expenses payable by us. In December 2020, we issued and sold 5,102,041 shares of common stock at a public offering price of $ 24.50 per share and pre-funded warrants to purchase 2,040,816 shares of common stock at a public offering price of $ 24.4999 per warrant in an underwritten public offering pursuant to a shelf registration on Form S-3. The gross proceeds from this public offering were $ 175.0 million, resulting in net proceeds of $ 164.3 million, after deducting underwriting discounts and commissions and estimated offering expenses payable by us. The terms of the pre-funded warrants issued and sold as part of the 2020 public offerings were similar to those issued and sold in 2019. As of December 31, 2022, all of the pre-funded warrants issued and sold as part of the 2020 underwritten public offerings were outstanding. ATM Facilities In the past three years, we have entered into two separate sales agreements with Cowen and Company, LLC (Cowen): in February 2020 (the “2020 ATM Facility”) and in November 2021 (the “2021 ATM Facility”). Each ATM facility provides or provided for the sale, in our sole discretion, of shares of our common stock having an aggregate offering price of up to $ 100.0 million, through Cowen, as our sales agent and the 2021 ATM Facility did not replace the 2020 ATM Facility in any way. The issuance and sale of these shares by us pursuant to the ATM facilities are deemed “at the market” offerings defined in Rule 415 under the Securities Act of 1933, as amended (the Securities Act), and were registered under the Securities Act. Commissions of up to 3.0 % are due on the gross sales proceeds of the common stock sold under each ATM facility. During the fiscal year ended December 31, 2021, we sold an aggregate of 6,240,601 shares of common stock under the ATM facilities, at an average price of $ 16.23 per share, for gross proceeds of $ 101.3 million and net proceeds of $ 98.9 million, after deducting commissions and other offering expenses payable by us. During the year ended December 31, 2022, we sold an aggregate of 1,618,672 shares of common stock under the 2021 ATM Facility, at an average price of $ 13.84 per share, for gross proceeds of $ 22.4 million and net proceeds of $ 22.0 million, after deducting commissions and other offering expenses payable by us. As of December 31, 2022 , we had fully utilized the 2020 ATM Facility and we had $ 55.9 million of common stock remaining and available to be sold under the 2021 ATM Facility. Equity Incentive Plans In March 2014, we adopted the 2014 Equity Incentive Plan (“2014 EIP”), which was amended and restated on October 15, 2014 upon the pricing of our initial public offering (“IPO”). The 2014 EIP provides for annual increases in the number of shares available for issuance thereunder on the first business day of each fiscal year, beginning with 2015 and ending in 2024, equal to five percent of the number of shares of the Company’s common stock outstanding as of such date or a lesser number of shares as determined by our board of directors. Under the terms of the 2014 EIP, we may grant stock options, RSAs and RSUs to employees, directors, consultants and other service providers. RSUs generally vest over four years . The fair value of RSUs, including those with performance conditions, is determined as the closing stock price on the date of grant. In February 2018, we adopted the 2018 Inducement Plan (“Inducement Plan”), under which we may grant options, stock appreciation rights, RSAs and RSUs to new employees. In November 2020, September 2021 and June 2022, we amended the Inducement Plan to reserve an additional 1,500,000 shares of the Company’s common stock for issuance under the Inducement Plan in each case. In 2020, we granted performance-based awards to certain of our employees that provide for the issuance of common stock if specified Company performance criteria related to our clinical programs are achieved. The number of performance-based awards that ultimately vests depends upon if, when and which performance criteria are achieved, as well as the employee’s continuous service, as defined in the 2014 EIP, through the date of vesting. None of the performance criteria were achieved by the required deadlines set forth in the award agreements and they were subsequently forfeited. Stock options are granted with exercise prices at no less than 100 % of the fair value of the shares on the date of grant as determined by the board of directors, provided, however, that the exercise price of an option granted to a 10% shareholder cannot be less than 110% of the fair value of the shares on the date of grant. The estimated fair value of the shares is generally equal to the closing market price of the Company’s common stock on the measurement date. Options granted generally vest over four years and expire in seven to ten years . In 2022, we granted performance-based stock options to certain of our employees that provide for the issuance of stock options to purchase common stock if specified Company performance criteria related to business development initiatives are achieved. The number of performance-based awards that ultimately vests depends upon if performance criteria are achieved within a specified timeline, as well as the employee’s continuous service, as defined in the 2014 EIP, through the date of vesting. None of the performance criteria have been achieved as of December 31, 2022 and the amount of outstanding awards is not material. As of December 31, 2022, a total of 18,781,047 shares of common stock were reserved for issuance under the 2014 EIP, of which 4,702,072 shares were available for future grant and 14,078,975 shares were subject to outstanding options and RSUs, including performance-based awards. As of December 31, 2022, 5,191,916 shares of common stock were reserved for issuance under the Inducement Plan, of which 1,916,728 shares were available for future grant and 3,275,188 shares were subject to outstanding options and RSUs. Restricted Stock Units The following is a summary of RSU activity under our 2014 EIP and Inducement Plan: RSUs Shares Weighted Balance as of December 31, 2021 5,592,358 $ 16.22 Granted 5,947,417 $ 8.26 Forfeited ( 2,583,871 ) $ 13.27 Vested ( 2,247,296 ) $ 15.29 Balance as of December 31, 2022 6,708,608 $ 10.61 The weighted average grant date fair value of RSUs granted during the years ended December 31, 2022, 2021 and 2020 was $ 8.26 , $ 16.42 and $ 12.19 , respectively. The estimated fair value of RSUs that vested in the years ended December 31, 2022, 2021 and 2020 was $ 34.4 million, $ 27.1 million and $ 23.6 million, respectively. As of December 31, 2022, there was $ 63.5 million of unrecognized stock-based compensation expense related to RSUs that is expected to be recognized over a weighted average period of 2.5 years. The aggregate intrinsic value of the RSUs outstanding as of December 31, 2022 was $ 22.0 million. Under our RSU settlement procedures, for some of the RSUs granted to our employees, we withhold shares at settlement to cover the estimated payroll withholding tax obligations. During 2022 , we settled 2,247,296 shares underlying RSUs, of which 114,444 shares underlying RSUs were net settled by withholding 43,524 shares. The value of the shares underlying RSUs withheld was $ 0.6 million, based on the closing price of our common stock on the settlement date. During 2021 , we settled 1,553,893 shares underlying RSUs, of which 154,341 shares underlying RSUs were net settled by withholding 61,385 shares. The value of the shares underlying RSUs withheld was $ 1.2 million, based on the closing price of our common stock on the settlement date. The value of RSUs withheld in each period was remitted to the appropriate taxing authorities and has been reflected as a financing activity in our consolidated statements of cash flows. Stock Options The following is a summary of stock option activity under our 2014 EIP and Inducement Plan: Shares Weighted Average Exercise Price Weighted Average Aggregate Balance as of December 31, 2021 9,219,837 $ 20.81 6.4 $ 12,810 Granted 3,615,971 9.06 Exercised ( 15,989 ) 8.96 Forfeited or expired ( 2,174,264 ) 20.62 Balance as of December 31, 2022 10,645,555 $ 16.88 6.4 $ 42 Vested and expected to vest as of 10,645,555 $ 16.88 6.4 $ 42 Exercisable as of December 31, 2022 6,061,634 $ 21.21 4.7 $ — Aggregate intrinsic value represents the difference between the closing stock price of our common stock on December 31, 2022 and the exercise price of outstanding, in-the-money options. As of December 31, 2022 , there was $ 29.2 million of unrecognized stock-based compensation expense related to stock options that is expected to be recognized over a weighted average period of 2.4 years. This excludes unrecognized stock-based compensation expense for performance-based stock options that were deemed not probable of vesting in accordance with U.S. GAAP. Options for 15,989 , 246,867 , and 268,938 shares of our common stock were exercised during the years ended December 31, 2022, 2021 and 2020 , with an intrinsic value of $ 0.1 million, $ 0.8 million and $ 1.0 million, respectively. As we believe it is more likely than not that no stock option related tax benefits will be realized, we do no t record any net tax benefits related to exercised options. The fair value of each option issued was estimated at the date of grant using the Black-Scholes valuation model. The following table summarizes the weighted-average assumptions used as inputs to the Black-Scholes model and resulting weighted-average grant date fair values of stock options granted during the periods indicated: Year ended December 31, 2022 2021 2020 Assumptions: Expected term (years) 6.0 6.0 6.0 Expected volatility 73.2 % 75.9 % 76.8 % Risk-free interest rate 2.1 % 0.9 % 0.8 % Expected dividend yield 0.0 % 0.0 % 0.0 % Fair Value: Weighted-average estimated grant date fair value per share $ 5.88 $ 10.52 $ 7.96 Options granted 3,615,971 2,643,378 2,641,125 Total estimated grant date fair value $ 21,261,909 $ 27,808,000 $ 21,023,000 The estimated fair value of stock options that vested in the years ended December 31, 2022, 2021 and 2020 was $ 23.2 million, $ 26.6 million and $ 29.4 million, respectively. Employee Stock Purchase Plan In May 2014, we adopted the 2014 Employee Stock Purchase Plan (“2014 ESPP”), which became effective on October 15, 2014 upon the pricing of our IPO. The 2014 ESPP permits eligible employees to purchase common stock at a discount through payroll deductions during defined offering periods. Eligible employees can purchase shares of the Company’s common stock at 85 % of the lower of the fair market value of the common stock at (i) the beginning of the offering period or (ii) at the end of the purchase period. The Company recorded $ 1.1 million, $ 1.7 million and $ 1.8 million of expense related to the 2014 ESPP in the years ended December 31, 2022, 2021 and 2020 , respectively. A total of 417,081 , 319,190 and 282,514 shares were purchased under the ESPP during the years ended December 31, 2022, 2021 and 2020, respectively. As of December 31, 2022 , there was $ 0.4 million of unrecognized stock-based compensation expense related to the ESPP that is expected to be recognized by the end of second quarter of 2023. The 2014 ESPP provides for annual increases in the number of shares available for issuance thereunder on the first business day of each fiscal year, beginning with 2015 and ending in 2024, equal to the lower of (i) one percent of the number of shares of our common stock outstanding as of such date, (ii) 230,769 shares of our common stock, or (iii) a lesser number of shares as determined by our board of directors. As of December 31, 2022 , there were 2,048,280 shares authorized under the 2014 ESPP. Reserved Shares The following shares of common stock were reserved for future issuance under our equity incentive plans as of December 31, 2022: Total Shares Reserved 2014 Equity Incentive Plan 18,781,047 2018 Inducement Plan 5,191,916 2014 Employee Stock Purchase Plan 676,070 Total reserved shares of common stock 24,649,033 Stock-based Compensation Expense Total stock-based compensation expense related to all stock awards was as follows: Year Ended December 31, 2022 2021 2020 (in thousands) Research and development $ 31,363 $ 32,063 $ 31,527 General and administrative 22,475 21,802 19,824 Total stock-based compensation expense $ 53,838 $ 53,865 $ 51,351

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	12. Income Taxes Losses before provision for income taxes were as follows in each period presented: Year Ended December 31, 2022 2021 2020 (in thousands) United States $ ( 228,395 ) $ ( 340,301 ) $ ( 306,758 ) Foreign 105 206 153 Total loss before provision for income taxes $ ( 228,290 ) $ ( 340,095 ) $ ( 306,605 ) The components of provision for income taxes were as follows in each period presented: Year Ended December 31, 2022 2021 2020 (in thousands) Current provision for income taxes: State $ — $ 4 $ 2 Foreign 12 42 13 Total current provision for income taxes $ 12 $ 46 $ 15 A reconciliation of statutory tax rates to effective tax rates were as follows in each of the periods presented: Year Ended December 31, 2022 2021 2020 Federal income taxes at statutory rate 21.0 % 21.0 % 21.0 % Research tax credits 7.8 % — — Stock-based compensation ( 3.8 %) ( 2.0 %) ( 2.4 %) Other ( 0.2 %) ( 0.3 %) 0.2 % Change in valuation allowance ( 24.8 %) ( 18.7 %) ( 18.8 %) Effective tax rate 0.0 % 0.0 % 0.0 % Deferred tax assets and liabilities reflect the net tax effects of (a) temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes and (b) operating loss and tax credit carryforwards. Significant components of our deferred tax assets and liabilities were as follows for each of the dates presented: As of December 31, 2022 2021 (in thousands) Deferred tax assets: Net operating loss carryforwards $ 302,591 $ 308,997 Capitalized research expenses 50,522 10,499 Tax credit carryforwards 19,427 1,580 Stock-based compensation 19,201 24,181 Deferred revenue 10,069 12,133 Operating lease liabilities 15,857 7,972 License fees 6,877 8,716 Other 13,169 9,414 Total deferred tax assets 437,713 383,492 Valuation allowance ( 422,493 ) ( 376,071 ) Total deferred tax assets 15,220 7,421 Deferred tax liabilities: Operating lease assets ( 15,220 ) ( 7,421 ) Total deferred tax liabilities ( 15,220 ) ( 7,421 ) Net deferred tax assets (liabilities) $ — $ — Beginning January 1, 2022, the Tax Cuts and Jobs Act (the "Tax Act”) eliminated the option to deduct research and development expenditures in the current year and requires taxpayers to capitalize such expenses pursuant to Internal Revenue Code (“IRC”) Section 174. The capitalized expenses are amortized over a 5 -year period for domestic expenses and a 15 -year period for foreign expenses. As a result of this provision of the Tax Act, deferred tax assets related to capitalized research expenses pursuant to IRC Section 174 increased by $ 43.7 million, partially offset by amortization on research expenses capitalized in prior years. Our tax credit carryforwards increased by $ 17.8 million, as compared to 2021, due to research and development and orphan drug credits generated during the current year. We regularly evaluate the positive and negative evidence in determining the realizability of our deferred tax assets. Based upon the weight of available evidence, which includes our historical operating performance and reported cumulative net losses since inception, we maintained a full valuation allowance on the net deferred tax assets as of December 31, 2022 and 2021. We intend to maintain a full valuation allowance on our deferred tax assets until sufficient positive evidence exists to support reversal of the valuation allowance. The valuation allowance increased by $ 46.4 million for the year ended December 31, 2022 due to the increase in our net deferred tax assets. In August 2022, the CHIPS and Science Act (“CHIPS Act”) and Inflation Reduction Act (“IRA”) were enacted, neither of which are expected to have a material impact to our financial statements. In addition, effective January 1, 2022, the California net operating loss deduction and temporary limit on business credits have been reinstated. The American Rescue Plan Act (“ARA”) was signed into law on March 11, 2021. We do not expect the ARA to have a material impact on our financial statements, however, given the potential changes to IRC Section 162(m) effective in 2027 as a result of the ARA, we will continue to monitor and assess. Under the Tax Act, federal net operating losses generated in tax years beginning on or after January 1, 2018 may be carried forward indefinitely, but the utilization of such federal net operating losses is limited to 80% of taxable income in future years. Since enactment, the IRS and Treasury have issued final and proposed regulations including clarifying guidance on several topics addressed by the Tax Act. Not all states conform to the Tax Act or and other states have varying conformity to the Tax Act. As of December 31, 2022, for federal income tax purposes, we had net operating loss carryforwards of approximately $ 1.0 billion of which $ 22.6 million begin to expire in 2036 and the remaining may be carried forward indefinitely, research & development tax credits of $ 24.0 million which begin to expire in 2032 , and orphan drug tax credits of $ 106.9 million which begin to expire in 2035 . During 2022, we utilized $ 42.7 million federal net operating losses to offset taxable income. For state income tax purposes, we had net operating loss carryforwards of approximately $ 1.3 billion which begin to expire in 2030 , research & development tax credits of $ 38.0 million which may be carried forward indefinitely, and California Completes tax credit of $ 2.0 million, which begins to expire in 2025 . Under IRC Section 382, as amended, substantial restrictions exist on the utilization of net operating loss and tax credit carryforwards in the event a corporation experienced an “ownership change.” Generally, a Section 382 “ownership change” occurs if one or more stockholders or groups of stockholders who owns at least 5% of a corporation’s stock increases its ownership by more than 50 percentage points over its lowest ownership percentage within a specified testing period. Similar rules may apply under state tax laws. Accordingly, our ability to utilize net operating loss and tax credit carryforwards may be limited as a result of such ownership changes, and such a limitation could result in the expiration of carryforwards before they are utilized. We have completed a Section 382 study of transactions in our stock through December 31, 2022. The study concluded that we have experienced ownership changes since inception and that our utilization of net operating loss carryforwards will be subject to annual limitations. However, it is not expected that the annual limitations will result in the expiration of tax attribute carryforwards prior to utilization. The changes in the balance of gross unrecognized tax benefits, which excludes interest and penalties, for the years ended December 31, 2020, 2021 and 2022 are as follows: (In thousands) Balance as of January 1, 2020 $ 86,000 Gross increases for tax positions related to current year 24,648 Gross increases for tax positions related to prior year — Gross decreases for tax positions related to prior year ( 47 ) Balance as of December 31, 2020 110,601 Gross increases for tax positions related to current year 28,171 Gross increases for tax positions related to prior year 5,295 Gross decreases for tax positions related to prior year — Balance as of December 31, 2021 144,067 Gross increases for tax positions related to current year 7,683 Gross increases for tax positions related to prior year — Gross decreases for tax positions related to prior year ( 785 ) Balance as of December 31, 2022 $ 150,965 We currently have a full valuation allowance against our U.S. net deferred tax assets, which would impact the timing of the effective tax rate benefit should any uncertain tax position be favorably settled in the future. The reversal of unrecognized tax benefits would not affect our effective tax rate to the extent we continue to maintain a full valuation allowance against our deferred tax assets. Our policy is to account for interest and penalties related to uncertain tax positions as a component of the income tax provision. We have no accrued interest and penalties as of December 31, 2022 and 2021 due to available tax losses. Our significant jurisdictions are the U.S. federal jurisdiction and the California state jurisdiction. All of our tax years remain open to examination by the U.S. federal and California tax authorities. We also file in other state, local and foreign jurisdictions in which we operate, and such tax years remain open to examination. As of December 31, 2022, we are not permanently reinvested with respect to its foreign earnings and has not recorded deferred income taxes and withholding taxes as these taxes are immaterial to the financial statements.

Supplemental Balance Sheet Info

Supplemental Balance Sheet Information	12 Months Ended
	Dec. 31, 2022
Supplemental Balance Sheet Information [Abstract]
Supplemental Balance Sheet Information	13. Supplemental Balance Sheet Information Inventories Inventories consist of the following: December 31, December 31, 2022 2021 (in thousands) Raw Materials $ 1,214 $ — Work-in-process 372 — Total inventories $ 1,586 $ — Property and equipment, net Property and equipment consisted of the following as of each period end: December 31, December 31, 2022 2021 (in thousands) Leasehold improvements $ 875 $ 50,142 Lab equipment 14,797 14,060 Machinery and equipment 572 5,228 Computer equipment and software 1,149 4,245 Furniture and fixtures 1,297 2,518 Construction in progress 32 6,325 Property and equipment, gross 18,722 82,518 Less: accumulated depreciation and amortization ( 12,422 ) ( 28,738 ) Property and equipment, net $ 6,300 $ 53,780 Depreciation and amortization expense was $ 5.7 million, $ 9.3 million and $ 8.3 million for the years ended December 31, 2022, 2021 and 2020, respectively. Other current liabilities Other current liabilities consisted of the following as of each period end: December 31, December 31, 2022 2021 (in thousands) Accrued operating expenses $ 7,435 $ 5,960 Current portion of operating lease liabilities 12,806 2,582 Current portion of finance lease liabilities 834 171 Other accrued liabilities 319 344 Total other current liabilities $ 21,394 $ 9,057

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2022
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Atara and our wholly owned subsidiaries. All intercompany balances and transactions are eliminated in consolidation.
Segment and Geographic Information	Segment and Geographic Information We operate and manage our business as one operating and reportable segment, which is the business of developing therapeutics. Our Chief Executive Officer, who is our chief operating decision maker, reviews financial information on an aggregate basis for purposes of allocating resources and evaluating financial performance. Substantially all of our assets are located in the U.S. Of the $ 63.6 million license and collaboration revenue recognized in 2022 , $ 61.8 million related to our agreements with Bayer, a German company, and $ 1.8 million related to our agreements with Pierre Fabre, a French company.
Use of Estimates	Use of Estimates We prepare our consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”), which requires us to make estimates and assumptions that affect the amounts reported in our consolidated financial statements and accompanying notes. The level of uncertainty in estimates and assumptions increases with the length of time until the underlying transactions are completed. Significant estimates and assumptions relied upon in preparing these financial statements include those related to revenue recognition, accrued research and development expenses, stock-based compensation expense and income taxes. Additionally, we use available market information to assess the fair value of our short-term investments. Actual results could differ materially from those estimates. If actual amounts differ from estimates, we include the updates in our consolidated results of operations in the period the actual amounts become known. Historically, the aggregate differences, if any, between our estimates and actual amounts in any year have not had a material effect on our consolidated financial statements.
Liquidity Risk	Liquidity Risk We have incurred significant operating losses since inception and have relied primarily on public and private equity financings and receipts from commercialization and license and collaboration agreements to fund our operations. As we continue to incur losses, our transition to profitability will depend on the successful development, approval and commercialization of product candidates and on the achievement of sufficient revenues to support our cost structure. We may never achieve sustained operating cash inflows or profitability. We expect that existing cash, cash equivalents and short-term investments as of December 31, 2022 , together with the $ 40.0 million received in January 2023 for achievement of certain milestones under the Pierre Fabre Commercialization Agreement, will be sufficient to fund our planned operations for at least the next twelve months from the date of issuance of these financial statements. However, the uncertainties inherent in Atara’s future operations and in our ability to obtain additional funding may raise substantial doubt about our ability to continue as a going concern in future reporting periods. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty. Although we have been successful in raising capital in the past, and expect to continue to raise capital as required, there is no assurance that we will be successful in obtaining additional funding on terms acceptable to us, if at all. If we are unable to obtain sufficient funding on acceptable terms, we could be forced to delay, limit, reduce or terminate preclinical studies, clinical studies or other development activities for one or more of our product candidates.
Concentration of Credit Risk and Other Uncertainties	Concentration of Credit Risk and Other Uncertainties We place cash and cash equivalents in the custody of financial institutions that management believes are of high credit quality, the amount of which at times, may be in excess of the amount insured by the Federal Deposit Insurance Corporation. We also make short-term investments in money market funds; U.S. Treasury, government agency and corporate debt obligations; commercial paper; certificates of deposit; and asset-backed securities, which can be subject to certain credit risk. However, we mitigate the risks by investing in high-grade instruments, limiting our exposure to any one issuer and monitoring the ongoing creditworthiness of the financial institutions and issuers.
Currency Translation	Currency Translation Transactions and monetary assets and liabilities that are denominated in a foreign currency are translated into U.S. dollars at the current exchange rate on the transaction date and as of each balance sheet date, respectively, with gains or losses on foreign exchange changes recognized in interest and other income (expense), net in the consolidated statements of operations and comprehensive loss. Foreign currency-denominated monetary assets and liabilities as of December 31, 2022 were not material.
Cash, Cash Equivalents and Short-Term Investments	Cash, Cash Equivalents and Short-Term Investments Cash and cash equivalents are defined as highly liquid investments with original maturities of 90 days or less at the date of purchase. Investments with original maturities of greater than 90 days are classified as short-term investments on the balance sheet. As our entire investment portfolio is considered available for use in current operations, we classify all investments as available-for-sale and as current assets, even though the stated maturity may be more than one year from the current balance sheet date. Available-for-sale securities are carried at fair value, with unrealized gains and losses reported in accumulated other comprehensive loss, which is a separate component of stockholders’ equity in the consolidated balance sheet. The amortized cost of securities is adjusted for amortization of premiums and accretion of discounts to maturity, which are both recorded to interest and other income (expense), net in the consolidated statements of operations and comprehensive loss. Changes in the fair value of available-for-sale securities impact the consolidated statements of operations and comprehensive loss only when such securities are sold, if an allowance for credit losses is recognized or if an impairment is recognized. Realized gains and losses on the sale of securities are determined by specific identification of each security’s cost basis. We regularly review our investment portfolio to determine if any security is impaired, which would require us to record an allowance for credit losses or impairment charge in the period any such determination is made. In making this judgment, we evaluate, among other things, the duration and extent to which the fair value of a security is less than its cost, our intent to sell or whether it is more likely than not that we will be required to sell the security before recovery of its amortized cost basis, the financial condition of the issuer and any changes thereto, and, as necessary, the portion of a decline in fair value that is credit-related. This assessment could change in the future due to new developments or changes in assumptions related to any particular security. Realized gains and losses, allowances for credit losses and impairments on available-for-sale securities, if any, are recorded to interest and other income, net in the statements of operations and comprehensive loss.
Fair Value Measurement	Fair Value Measurement The carrying amounts of certain of our financial instruments including cash equivalents, accounts receivable, other current assets, accounts payable and accrued liabilities approximate fair value due to their short maturities. Short-term investments are comprised of available-for-sale securities, which are carried at fair value.
Financial Instruments	Financial Instruments Our financial assets are measured at fair value on a recurring basis using the following hierarchy to prioritize valuation inputs, in accordance with applicable GAAP: Level 1: Quoted prices in active markets for identical assets or liabilities that we have the ability to access Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data such as quoted prices, interest rates and yield curves Level 3: Inputs that are unobservable data points that are not corroborated by market data We review the fair value hierarchy classification on a quarterly basis. Changes in the ability to observe valuation inputs may result in a reclassification of levels of certain securities within the fair value hierarchy. We recognize transfers into and out of levels within the fair value hierarchy in the period in which the actual event or change in circumstances that caused the transfer occurs. There have been no transfers between Level 1, Level 2, and Level 3 in any periods presented. Financial assets and liabilities are considered Level 2 when their fair values are determined using inputs that are observable in the market or can be derived principally from or corroborated by observable market data such as pricing for similar securities, recently executed transactions, cash flow models with yield curves, and benchmark securities. In addition, Level 2 financial instruments are valued using comparisons to like-kind financial instruments and models that use readily observable market data as their basis. U.S. Treasury, government agency and corporate debt obligations, commercial paper and asset-backed securities are valued primarily using market prices of comparable securities, bid/ask quotes, interest rate yields and prepayment spreads and are included in Level 2. Financial assets and liabilities are considered Level 3 when their fair values are determined using pricing models, discounted cash flow methodologies, or similar techniques, and at least one significant model assumption or input is unobservable. We have no Level 3 financial assets or liabilities.
Accounts Receivable, net	Accounts Receivable, net Accounts receivable are recorded net of estimates of variable consideration for which reserves are established and which result from discounts and chargebacks that are offered within contracts between us and a limited number of specialty pharmacies and a specialty distributor in the United States. These reserves are classified as reductions of accounts receivable. We estimate the allowance for doubtful accounts using the current expected credit loss model, or CECL model. Under the CECL model, the allowance for doubtful accounts reflects the net amount expected to be collected from the accounts receivable. We evaluate the collectability of these cash flow based on the asset’s amortized cost, the risk of loss even when that risk is remote, losses over an asset’s contractual life, and other relevant information available to us. Accounts receivable balances are written off against the allowance when it is probable that the receivable will not be collected. Given the nature and history of our accounts receivable, we determined that an allowance for doubtful accounts was not required as of the periods presented.
Inventories	Inventories Inventories are stated at the lower of cost or estimated net realizable value, on a specific identification basis. We use actual costs to determine our cost basis for inventories. Inventories consist of raw materials, work-in-process and finished goods. Finished goods inventories in excess of one year of forecasted sales are classified in the Consolidated Balance Sheets as non-current “Other assets.” We begin capitalizing costs as inventory when the product candidate receives regulatory approval and when the manufacturing facility producing such inventory is qualified by the relevant regulatory agency. Prior to regulatory approval and qualification, we record such production costs related to product candidates as research and development expenses. Any manufactured product that is available for commercial sale is recorded to inventory; to the extent it is later used for clinical studies, such inventory costs are then recorded within research and development expenses. We periodically assess the recoverability of our inventory and reduce the carrying value of the inventory when items are determined to be obsolete, defective or in excess of forecasted sales requirements. Inventory write-downs for excess, defective and obsolete inventory are recorded as a cost of sales. There have been no write-downs of our inventories for the periods presented.
Property and Equipment, Net	Property and Equipment, net Property and equipment are stated at cost and depreciated using the straight-line method over the estimated useful lives of the assets, ranging from three to five years , except for leasehold improvements, which are depreciated on a straight-line basis over the lesser of the estimated useful life of the leasehold improvement or the lease term. Costs incurred to acquire, construct or install property and equipment during the construction stage of a capital project or costs incurred to purchase and develop internal use software during the application development stage are recorded as construction in progress. Maintenance and repairs are charged to operations as incurred.
Long-lived Assets	Long-lived Assets We evaluate the carrying amount of our long-lived assets whenever events or changes in circumstances indicate that the assets may not be recoverable. An impairment loss would be recognized when estimated future cash flows expected to result from the use of the asset and its eventual disposition are less than the carrying amount of the asset. To date, there have been no such impairment losses.
Asset Retirement Obligations ("ARO")	Asset Retirement Obligation (“ARO”) An ARO is a legal obligation associated with the retirement of long-lived assets pertaining to leasehold improvements. These liabilities are initially recorded at fair value and the related asset retirement costs are capitalized by increasing the carrying amount of the related assets by the same amount as the liability. Asset retirement costs are subsequently depreciated over the useful lives of the related assets. Subsequent to initial recognition, the Company records period-to-period changes in the ARO liability resulting from the passage of time and revisions to either the timing or the amount of the original estimate of undiscounted cash flows. The Company derecognizes ARO liabilities when the related obligations are settled.
Leases	Leases We determine if a contract is or contains a lease at contract inception. Operating leases are included in operating lease assets, other current liabilities, and operating lease liabilities on our consolidated balance sheets. Our policy is to not recognize right-of-use (“ROU”) assets and lease liabilities for short-term operating leases with terms of 12 months or less; we recognize short-term lease expense for these leases on a straight-line basis over the lease term. Long-term operating lease ROU assets and long-term operating lease liabilities are presented separately and operating lease liabilities payable in the next twelve months are recorded in other current liabilities. Finance lease ROU assets are recorded in other assets and the related finance lease liabilities are presented in other current liabilities and other long-term liabilities. Lease assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. The lease term includes renewal options that we are reasonably certain of exercising as of the commencement date. None of the lease terms used to calculate the future minimum lease payments at commencement date include renewal options. As most of our leases do not provide an implicit rate, we use our incremental borrowing rate based on the information available at commencement date in determining the present value of future payments. The incremental borrowing rate for our leases is determined based on lease term and currency in which lease payments are made, adjusted for impacts of collateral. Lease assets also includes any lease payments made and excludes lease incentives and initial direct costs incurred. Operating lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. Finance lease assets are amortized over the shorter of the lease term or the asset’s estimated useful life. Our facilities and equipment operating leases have lease and non-lease components and we have made a policy election to account for the lease and non-lease components as a single lease component. We are considered the sub-lessor for certain of our leases where we have entered into a sub-lease agreement with or have assigned our lease to another party. Rental income was not material for any period presented and we record rental income as a reduction to rent expense within operating expenses.
Accruals of Research and Development Costs	Accruals of Research and Development Costs We record accruals for estimated research and development costs based on an evaluation of our vendors’ progress towards completion of specific tasks, using data such as patient enrollment, clinical site activations or information provided to us by our vendors regarding their actual costs incurred. Payments for these activities are based on the terms of individual contracts and payment timing may differ significantly from the period in which the services are performed. We determine accrual estimates through reports from and discussions with internal personnel and outside service providers as to the progress or state of completion of studies, or the services completed. Our estimates of accrued expenses as of each balance sheet date are based on the facts and circumstances known at the time. Costs that are paid in advance of performance are deferred as a prepaid expense and amortized over the period in which the services are provided.
Sale of Future Revenues Policy Text Block	Sale of Future Revenues To the extent that we account for the sale of future revenues as debt in accordance with ASC 470, we amortize the liability and recognize interest expense related to the sale of future revenues using the effective interest rate method over the estimated life of the underlying agreement. The liability and related interest expense are based on our current estimate of expected future payments over the life of the arrangement. We will re-assess the amount and timing of expected payments each reporting period using a combination of internal projections and forecasts from external resources and record interest expense on the carrying value of the liability using the imputed effective interest rate on a prospective basis.
Revenue Recognition	Revenue Recognition For contracts that are determined to be within the scope of Accounting Standards Codification Topic 606 (Accounting Standards Update (“ASU”) No. 2014-09), Revenue from Contracts with Customers , and all subsequent amendments (collectively, “ASC 606”), revenue is recognized as we satisfy performance obligations and when a customer obtains control of the promised goods or services. The amount of revenue recognized reflects the consideration to which we expect to be entitled to receive in exchange for these goods and services. To achieve this core principle, we apply the following five steps (i) identify the contract with the customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when or as we satisfy a performance obligation. We only apply the five-step model to contracts when we determine that collection of substantially all consideration for goods and services that are transferred is probable based on the customer’s intent and ability to pay the promised consideration. Performance obligations promised in a contract are identified based on the goods and services that will be transferred to the customer that are both capable of being distinct and are distinct in the context of the contract. To the extent a contract includes multiple promised goods and services, we apply judgment to determine whether promised goods and services are both capable of being distinct and distinct in the context of the contract. If these criteria are not met, the promised goods and services are accounted for as a combined performance obligation. The transaction price is determined based on the consideration to which we will be entitled in exchange for transferring goods and services to the customer. To the extent the transaction price includes variable consideration, we estimate the amount of variable consideration that should be included in the transaction price utilizing either the expected value method or the most likely amount method, depending on the nature of the variable consideration. Variable consideration is included in the transaction price if, in our judgment, it is probable that a significant future reversal of cumulative revenue under the contract will not occur. Any estimates, including the effect of the constraint on variable consideration, are evaluated at each reporting period for any changes. Determining the transaction price requires significant judgment, which is discussed in further detail for our out-license agreements in Note 5. Our out-license agreements do not contain a significant financing component. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation on a relative standalone selling price basis unless the transaction price is variable and meets the criteria to be allocated entirely to a performance obligation or to a distinct service that forms part of a single performance obligation. The consideration to be received is allocated among the separate performance obligations based on relative standalone selling prices. We typically determine standalone selling prices using an expected cost plus margin approach model. We satisfy performance obligations either over time or at a point in time. Revenue is recognized over time if either (i) the customer simultaneously receives and consumes the benefits provided by our performance, (ii) our performance creates or enhances an asset that the customer controls as the asset is created or enhanced or (iii) our performance does not create an asset with an alternative use to the entity and we have an enforceable right to payment for performance completed to date. We evaluate the measure of progress each reporting period and, if necessary, adjust the measure of performance and related revenue recognition. If we do not satisfy a performance obligation over time, the related performance obligation is satisfied at a point in time by transferring control of a promised good or service to a customer. As of December 31, 2022, our deferred revenue is related to the Pierre Fabre Commercialization Agreement, which is within the scope of ASC 606. As discussed in further detail in Note 5, the terms of these arrangements include potential payments to us for some or all of the following: nonrefundable, upfront fees; development, regulatory, and commercial milestone payments; research and development funding payments; and royalties on the net sales of licensed products. These payments relate to promised goods or services for which revenue will be recognized upon our satisfaction of the underlying performance obligations. Licenses of intellectual property : If the license of our intellectual property is determined to be distinct from the other performance obligations identified in an arrangement, we recognize revenues from consideration allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. For licenses that are combined with other promises, we utilize judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. Upfront payments : Upfront payments and fees are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until we have satisfied our obligations under these arrangements. Milestone payments : At the inception of each arrangement that includes development milestone payments, we evaluate the probability of reaching the milestones and estimates the amount to be included in the transaction price using the most likely amount method. If it is probable that a significant revenue reversal would not occur in the future, the associated milestone value is included in the transaction price. The transaction price is then allocated to each performance obligation on a relative standalone selling price basis, for which we recognize revenue as or when the performance obligations under the contract are satisfied. At the end of each subsequent reporting period, we re-evaluate the probability of achievement of such development milestones and any related constraint and, if necessary, adjusts its estimate of the overall transaction price. Any such adjustments are recorded on a cumulative catch-up basis, which would affect license and collaboration revenues and the consolidated statements of operations and comprehensive loss in the period of adjustment. Royalties : For arrangements that include sales-based royalties, including milestone payments based on levels of sales, if the license is deemed to be the predominant item to which the royalties relate, we recognize revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied, or partially satisfied. To date, we have not recognized any royalty revenue resulting from our out-licensing agreements. Certain judgments affect the application of our revenue recognition policy. For example, we record short-term and long-term deferred revenue based on our best estimate of when such revenue will be recognized. Short-term deferred revenue consists of amounts that are expected to be recognized as revenue in the next 12 months, and long-term deferred revenue consists of amounts that we do not expect will be recognized in the next 12 months. This estimate is based on our forecasted patient demand and current operating plan and, if patient demand or our operating plan should change in the future, we may recognize a different amount of deferred revenue over the next 12-month period.
Research and Development Expense	Research and Development Expense Research and development expense consists of costs incurred in performing research and development activities, including compensation and benefits for research and development employees; expenses incurred under agreements with contract research organizations and investigative sites that conduct clinical and preclinical studies; expense incurred under agreements with contract manufacturing organizations related to acquiring and manufacturing clinical study materials and other supplies to support the manufacture of our product candidates; payments under licensing and research and development agreements; other outside services and consulting costs, and facilities, information technology and overhead expenses. Research and development costs are expensed as incurred.
Stock-Based Compensation Expense	Stock-Based Compensation Expense We account for stock-based compensation expense, including the expense of restricted common stock awards (“RSAs”), grants of restricted stock units (“RSUs”), and stock options that may be settled in shares of our common stock, based on the fair values of the equity instruments issued. The fair value is determined on the measurement date, which is generally the date of grant. The fair value of our RSUs is measured at the closing market price of our common stock on the measurement date. The fair value for our stock option awards is determined at the grant date using the Black-Scholes valuation model. In determining the fair value of stock option awards granted, we use the Black-Scholes valuation model and assumptions include: Expected term – We derived the expected term using the “simplified” method (the expected term is determined as the average of the time-to-vesting and the contractual life of the options), as we have limited historical information to develop expectations about future exercise patterns and post vesting employment termination behavior. Expected volatility – Prior to 2021, expected volatility was estimated using comparable public companies’ volatility for similar terms. Beginning in 2021, volatility is estimated using an average of Atara’s historical volatility and comparable public companies’ volatility for similar terms. Expected dividend – We have not historically declared or paid dividends to our stockholders and have no plans to pay dividends; therefore, we assumed an expected dividend yield of 0 %. Risk-free interest rate – The risk-free interest rate is based on the yield on U.S. Treasury securities with the expected term of the associated award. For awards with performance-based vesting criteria, we assess the probability of the achievement of the performance conditions at the end of each reporting period and begin to recognize the share-based compensation costs when it becomes probable that the performance conditions will be met. For awards that are subject to both service and performance conditions, no expense is recognized until it is probable that performance conditions will be met. Stock-based compensation expense for awards with time-based vesting criteria is recognized as expense on a straight-line basis over the requisite service period. Stock-based compensation expense for awards with performance and other vesting criteria is recognized as expense under an accelerated graded vesting model. We account for forfeitures of stock-based awards as they occur.
Defined Contribution Plan	Defined Contribution Plan We have one qualified 401(k) plan covering all eligible employees. Under the plan, employees may contribute up to the statutory allowable amount for any calendar year. We make matching contributions, equal to 50 % of each dollar contributed up to the first 6 % of an individual’s eligible earnings, up to the annual IRS maximum. For the years ended December 31, 2022, 2021 , and 2020 we recorded matching contributions of approximately $ 2.3 million, $ 2.6 million, and $ 2.1 million, respectively.
Income Taxes	Income Taxes We use the asset and liability method to account for income taxes. We record deferred tax assets and liabilities for the expected future tax consequences of temporary differences between the financial statement carrying amounts and the tax basis of assets and liabilities using enacted tax rates expected to be in effect when the differences are expected to reverse. Valuation allowances are provided when necessary to reduce net deferred tax assets to the amount that is more likely than not to be realized. Based on the available evidence, we are unable, at this time, to support the determination that it is more likely than not that our deferred tax assets will be utilized in the future. Accordingly, we recorded a full valuation allowance as of December 31, 2022 and 2021. We intend to maintain valuation allowances until sufficient evidence exists to support their reversal. Tax benefits related to uncertain tax positions are recognized when it is more likely than not that a tax position will be sustained during an audit. Interest and penalties related to unrecognized tax benefits are included within the provision for income tax.
Comprehensive Income (Loss)	Comprehensive Income (Loss) Comprehensive income (loss) is defined as a change in equity of a business enterprise during a period resulting from transactions from non-owner sources. Our other comprehensive income (loss) is comprised solely of unrealized gains (losses) on available-for-sale securities and is presented net of taxes. There have not been any material reclassifications from other comprehensive income (loss) to net loss recorded during any period presented.
Recent Accounting Pronouncements	Recent Accounting Pronouncements We consider the applicability and impact of any recent ASU issued by the Financial Accounting Standards Board (“FASB”). Based on our assessment, the ASUs were determined to be either not applicable or are expected to have minimal impact on our consolidated financial statements.

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	12 Months Ended
	Dec. 31, 2022
Earnings Per Share [Abstract]
Antidilutive Securities Excluded From Computation of Diluted Net Loss per Common Share	The following table represents the potential common shares issuable pursuant to outstanding securities as of the dates listed that were excluded from the computation of diluted net loss per common share, as their inclusion would have an antidilutive effect: As of December 31, 2022 2021 2020 Unvested RSUs 6,698,858 5,253,347 2,868,407 Vested and unvested options 10,336,634 9,200,337 7,832,386 ESPP share purchase rights 86,782 27,238 26,349 Total 17,122,274 14,480,922 10,727,142

Financial Instruments (Tables)

Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2022
Financial Instruments Disclosure [Abstract]
Summary of Estimated Fair Value and Related Valuation Input Hierarchy of Available-for-Sale Securities	The following tables summarize the estimated fair value and related valuation input hierarchy of our available-for-sale securities as of each period end: Total Total Total Total Amortized Unrealized Unrealized Estimated As of December 31, 2022: Input Level Cost Gain Loss Fair Value (in thousands) Money market funds Level 1 $ 78,033 $ — $ — $ 78,033 U.S. Treasury obligations Level 2 63,013 3 ( 394 ) 62,622 Government agency obligations Level 2 8,086 — ( 48 ) 8,038 Corporate debt obligations Level 2 82,598 4 ( 1,513 ) 81,089 Commercial paper Level 2 996 — — 996 Asset-backed securities Level 2 6,343 — ( 119 ) 6,224 Total available-for-sale securities 239,069 7 ( 2,074 ) 237,002 Less: amounts classified as cash equivalents ( 87,122 ) ( 3 ) — ( 87,125 ) Amounts classified as short-term investments $ 151,947 $ 4 $ ( 2,074 ) $ 149,877 Total Total Total Total Amortized Unrealized Unrealized Estimated As of December 31, 2021: Input Level Cost Gain Loss Fair Value (in thousands) Money market funds Level 1 $ 89,738 $ — $ — $ 89,738 U.S. Treasury obligations Level 2 111,832 1 ( 138 ) 111,695 Government agency obligations Level 2 21,346 — ( 23 ) 21,323 Corporate debt obligations Level 2 99,757 6 ( 190 ) 99,573 Commercial paper Level 2 36,993 — — 36,993 Asset-backed securities Level 2 10,174 1 ( 25 ) 10,150 Total available-for-sale securities 369,840 8 ( 376 ) 369,472 Less: amounts classified as cash equivalents ( 104,488 ) — — ( 104,488 ) Amounts classified as short-term investments $ 265,352 $ 8 $ ( 376 ) $ 264,984
Amortized Cost and Fair Value of Available for Sale Securities by Contractual Maturity	The amortized cost and fair value of our available-for-sale securities by contractual maturity were as follows: As of December 31, 2022 As of December 31, 2021 Amortized Estimated Amortized Estimated Cost Fair Value Cost Fair Value (in thousands) (in thousands) Maturing within one year $ 202,323 $ 201,359 $ 278,457 $ 278,354 Maturing in one to five years 36,746 35,643 91,383 91,118 Total available-for-sale securities $ 239,069 $ 237,002 $ 369,840 $ 369,472
Reconciliation of Cash, Cash Equivalents and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents and restricted cash within the consolidated balance sheets that sum to the total of the same such amounts in the consolidated statement of cash flows: December 31, December 31, 2022 2021 (in thousands) Cash and cash equivalents $ 92,942 $ 106,084 Restricted cash - short-term 146 194 Restricted cash - long-term — 1,200 Total cash, cash equivalents and restricted cash $ 93,088 $ 107,478

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2022
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment	Property and equipment consisted of the following as of each period end: December 31, December 31, 2022 2021 (in thousands) Leasehold improvements $ 875 $ 50,142 Lab equipment 14,797 14,060 Machinery and equipment 572 5,228 Computer equipment and software 1,149 4,245 Furniture and fixtures 1,297 2,518 Construction in progress 32 6,325 Property and equipment, gross 18,722 82,518 Less: accumulated depreciation and amortization ( 12,422 ) ( 28,738 ) Property and equipment, net $ 6,300 $ 53,780

Liability Related to the Sale_2

Liability Related to the Sale of Future Royalties (Tables)	12 Months Ended
	Dec. 31, 2022
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Schedule of liability related to the sale of future royalties [Table Text Block]	: For the year ended December 31, 2022 (in thousands) Liability related to the sale of future revenues, beginning balance $ — Proceeds from sale of future revenues, net 30,605 Less: debt issuance costs ( 368 ) Liability related to the sale of future revenues, ending balance $ 30,237

Sale of ATOM Facility (Tables)

Sale of ATOM Facility (Tables)	12 Months Ended
	Dec. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
Summary of the carrying amount assets sold and the gain on sale	Refer to the summary of assets sold and gain on sale of the ATOM Facility: (in thousands) Net proceeds from sale of ATOM Facility $ 94,765 Assets sold: Other current assets $ 190 Property and equipment, net 44,299 Other assets 39 Less: Assets sold 44,528 Gain on sale of ATOM Facility $ 50,237

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2022
Leases [Abstract]
Schedule of Maturities of Lease Liabilities Under Operating and Finance Leases	The maturities of lease liabilities under our operating and finance leases as of December 31, 2022 were as follows: Operating Leases Finance Leases Years Ending December 31, (in thousands) 2023 $ 19,158 $ 1,339 2024 18,035 1,242 2025 17,880 1,263 2026 16,557 1,285 2027 5,631 436 Thereafter 15,778 — Total lease payments $ 93,039 $ 5,565 Less: amount representing interest ( 22,169 ) ( 1,088 ) Present value of lease liabilities $ 70,870 $ 4,477 Balance as of December 31, 2022 Other current liabilities $ 12,806 $ 834 Operating lease liabilities - long-term 58,064 — Other long-term liabilities — 3,643 Total $ 70,870 $ 4,477
Components of Lease Cost	The components of lease cost were as follows: Year Ended Year Ended Year Ended December 31, 2022 December 31, 2021 December 31, 2020 (in thousands) Operating lease cost: Operating lease cost $ 14,245 $ 3,827 $ 3,020 Short-term lease cost 386 836 987 Total operating lease cost $ 14,631 $ 4,663 $ 4,007 Finance lease cost: Amortization expense $ 872 $ 244 $ 389 Interest on lease liabilities 373 29 60 Total finance lease cost $ 1,245 $ 273 $ 449
Summary of Other Information Related to Leases	Other information related to leases was as follows: Year Ended Year Ended Year Ended December 31, 2022 December 31, 2021 December 31, 2020 (in thousands, except lease term and discount rate) Supplemental Cash Flows Information Cash paid for amounts included in the measurement of Operating cash flows for operating leases $ 13,417 $ 3,738 $ 2,878 Operating cash flows for finance leases 335 32 62 Financing cash flows for finance leases 518 254 389 Operating lease assets obtained in exchange for lease obligations: $ 50,779 $ 13,427 $ — Finance lease assets obtained in exchange for lease obligations: 4,795 — 281 Non-cash increase to operating lease assets due to — 1,760 639 Weighted Average Remaining Lease Term Operating leases 5.9 years 9.2 years 9.4 years Finance leases 4.2 years 1.0 years 1.7 years Weighted Average Discount Rate Operating leases 9.9 % 9.6 % 10.3 % Finance leases 10.4 % 9.7 % 9.7 %

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Dec. 31, 2022
Restructuring and Related Activities [Abstract]
Summarizes of future termination benefit payments	We recorded the following restructuring charges associated with the reduction in force: Year Ended December 31, 2022 (in thousands) Research and development expense $ 2,544 General and administrative expense 3,420 Total restructuring charges $ 5,964
Restructuring of Labiality Activity	Total Restructuring Charges (in thousands) Liability balance, January 1, 2022 $ — Charges 5,964 Cash payments ( 4,419 ) Liability balance, December 31, 2022 $ 1,545

Commitments And Contingencies (

Commitments And Contingencies (Tables)	12 Months Ended
	Dec. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Schedule of Minimum Commitment	The non-cancellable minimum commitments for products and services, subject to agreements with a term of greater than one year with clinical research organizations and CMOs, excluding those recognized on our balance sheet, as of December 31, 2022 are set forth below: Calendar Year Remaining Minimum Commitment as of December 31, 2022 (in thousands) 2023 $ 19,420 2024 14,085 2025 13,308 2026 9,605 2027 3,388 Total $ 59,806

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2022
Share-Based Payment Arrangement [Abstract]
Summary of RSU Activity	The following is a summary of RSU activity under our 2014 EIP and Inducement Plan: RSUs Shares Weighted Balance as of December 31, 2021 5,592,358 $ 16.22 Granted 5,947,417 $ 8.26 Forfeited ( 2,583,871 ) $ 13.27 Vested ( 2,247,296 ) $ 15.29 Balance as of December 31, 2022 6,708,608 $ 10.61
Summary of Stock Option Activity	The following is a summary of stock option activity under our 2014 EIP and Inducement Plan: Shares Weighted Average Exercise Price Weighted Average Aggregate Balance as of December 31, 2021 9,219,837 $ 20.81 6.4 $ 12,810 Granted 3,615,971 9.06 Exercised ( 15,989 ) 8.96 Forfeited or expired ( 2,174,264 ) 20.62 Balance as of December 31, 2022 10,645,555 $ 16.88 6.4 $ 42 Vested and expected to vest as of 10,645,555 $ 16.88 6.4 $ 42 Exercisable as of December 31, 2022 6,061,634 $ 21.21 4.7 $ —
Summary of Options Estimated with Weighted Average	The fair value of each option issued was estimated at the date of grant using the Black-Scholes valuation model. The following table summarizes the weighted-average assumptions used as inputs to the Black-Scholes model and resulting weighted-average grant date fair values of stock options granted during the periods indicated: Year ended December 31, 2022 2021 2020 Assumptions: Expected term (years) 6.0 6.0 6.0 Expected volatility 73.2 % 75.9 % 76.8 % Risk-free interest rate 2.1 % 0.9 % 0.8 % Expected dividend yield 0.0 % 0.0 % 0.0 % Fair Value: Weighted-average estimated grant date fair value per share $ 5.88 $ 10.52 $ 7.96 Options granted 3,615,971 2,643,378 2,641,125 Total estimated grant date fair value $ 21,261,909 $ 27,808,000 $ 21,023,000
Schedule of Common Stock Reserved for Future Issuance Under Equity Incentive Plans	The following shares of common stock were reserved for future issuance under our equity incentive plans as of December 31, 2022: Total Shares Reserved 2014 Equity Incentive Plan 18,781,047 2018 Inducement Plan 5,191,916 2014 Employee Stock Purchase Plan 676,070 Total reserved shares of common stock 24,649,033
Schedule of Stock-based Compensation Related to Stock Awards	Total stock-based compensation expense related to all stock awards was as follows: Year Ended December 31, 2022 2021 2020 (in thousands) Research and development $ 31,363 $ 32,063 $ 31,527 General and administrative 22,475 21,802 19,824 Total stock-based compensation expense $ 53,838 $ 53,865 $ 51,351

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Losses Before Provision for Income Taxes	Losses before provision for income taxes were as follows in each period presented: Year Ended December 31, 2022 2021 2020 (in thousands) United States $ ( 228,395 ) $ ( 340,301 ) $ ( 306,758 ) Foreign 105 206 153 Total loss before provision for income taxes $ ( 228,290 ) $ ( 340,095 ) $ ( 306,605 )
Components of Provision for Income Taxes	The components of provision for income taxes were as follows in each period presented: Year Ended December 31, 2022 2021 2020 (in thousands) Current provision for income taxes: State $ — $ 4 $ 2 Foreign 12 42 13 Total current provision for income taxes $ 12 $ 46 $ 15
Reconciliation of Statutory Tax Rates to Effective Tax Rates	A reconciliation of statutory tax rates to effective tax rates were as follows in each of the periods presented: Year Ended December 31, 2022 2021 2020 Federal income taxes at statutory rate 21.0 % 21.0 % 21.0 % Research tax credits 7.8 % — — Stock-based compensation ( 3.8 %) ( 2.0 %) ( 2.4 %) Other ( 0.2 %) ( 0.3 %) 0.2 % Change in valuation allowance ( 24.8 %) ( 18.7 %) ( 18.8 %) Effective tax rate 0.0 % 0.0 % 0.0 %
Components of Deferred Tax Assets and Liabilities	Significant components of our deferred tax assets and liabilities were as follows for each of the dates presented: As of December 31, 2022 2021 (in thousands) Deferred tax assets: Net operating loss carryforwards $ 302,591 $ 308,997 Capitalized research expenses 50,522 10,499 Tax credit carryforwards 19,427 1,580 Stock-based compensation 19,201 24,181 Deferred revenue 10,069 12,133 Operating lease liabilities 15,857 7,972 License fees 6,877 8,716 Other 13,169 9,414 Total deferred tax assets 437,713 383,492 Valuation allowance ( 422,493 ) ( 376,071 ) Total deferred tax assets 15,220 7,421 Deferred tax liabilities: Operating lease assets ( 15,220 ) ( 7,421 ) Total deferred tax liabilities ( 15,220 ) ( 7,421 ) Net deferred tax assets (liabilities) $ — $ —
Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits	The changes in the balance of gross unrecognized tax benefits, which excludes interest and penalties, for the years ended December 31, 2020, 2021 and 2022 are as follows: (In thousands) Balance as of January 1, 2020 $ 86,000 Gross increases for tax positions related to current year 24,648 Gross increases for tax positions related to prior year — Gross decreases for tax positions related to prior year ( 47 ) Balance as of December 31, 2020 110,601 Gross increases for tax positions related to current year 28,171 Gross increases for tax positions related to prior year 5,295 Gross decreases for tax positions related to prior year — Balance as of December 31, 2021 144,067 Gross increases for tax positions related to current year 7,683 Gross increases for tax positions related to prior year — Gross decreases for tax positions related to prior year ( 785 ) Balance as of December 31, 2022 $ 150,965

Supplemental Balance Sheet In_2

Supplemental Balance Sheet Information (Tables)	12 Months Ended
	Dec. 31, 2022
Supplemental Balance Sheet Information [Abstract]
Schedule of Inventories	Inventories consist of the following: December 31, December 31, 2022 2021 (in thousands) Raw Materials $ 1,214 $ — Work-in-process 372 — Total inventories $ 1,586 $ — Property and equipment, net
Schedule of Property and Equipment	Property and equipment consisted of the following as of each period end: December 31, December 31, 2022 2021 (in thousands) Leasehold improvements $ 875 $ 50,142 Lab equipment 14,797 14,060 Machinery and equipment 572 5,228 Computer equipment and software 1,149 4,245 Furniture and fixtures 1,297 2,518 Construction in progress 32 6,325 Property and equipment, gross 18,722 82,518 Less: accumulated depreciation and amortization ( 12,422 ) ( 28,738 ) Property and equipment, net $ 6,300 $ 53,780
Schedule of Other Current Liabilities	Other current liabilities consisted of the following as of each period end: December 31, December 31, 2022 2021 (in thousands) Accrued operating expenses $ 7,435 $ 5,960 Current portion of operating lease liabilities 12,806 2,582 Current portion of finance lease liabilities 834 171 Other accrued liabilities 319 344 Total other current liabilities $ 21,394 $ 9,057

Description of Business - Addit

Description of Business - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Aug. 31, 2022	Aug. 08, 2022	Apr. 04, 2022	Jan. 31, 2022
Description Of Business [Abstract]
Entity incorporation state	DE
Entity incorporation date	Aug. 01, 2012
Cash consideration pursuant to asset purchase agreement				$ 94.8	$ 100
Reduction in current workforce percentage		20%	20%
Supplemental unemployment benefits, severance benefits		$ 6	$ 6

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) Segment	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Significant Accounting Policies [Line Items]
Number of reportable segments | Segment		1
Number of operating segments | Segment		1
License and collaboration revenue		$ 63,573	$ 20,340	$ 0
Cash and cash equivalents maturity period		90 days
Investment maturity period		90 days
Impairment of long-lived assets		$ 0
Expected dividend yield		0%	0%	0%
Defined contribution plan, plan name		401(k)
Defined contribution plan, matching contribution percentage		50%
Defined contribution plan, maximum percentage of an individual's eligible earnings		6%
Defined contribution plan contributions by employer		$ 2,300	$ 2,600	$ 2,100
Minimum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life		3 years
Maximum
Significant Accounting Policies [Line Items]
Property, plant and equipment, useful life		5 years
Bayer Agreements
Significant Accounting Policies [Line Items]
License and collaboration revenue		$ 61,800
Pierre Fabre Commercialization Agreement
Significant Accounting Policies [Line Items]
License and collaboration revenue		$ 1,800
Pierre Fabre Commercialization Agreement | Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Payment received upon achievement of certain milestones	$ 40,000

Net Loss per Common Share - Ant

Net Loss per Common Share - Antidilutive Securities Excluded From Computation of Diluted Net Loss per Common Share (Detail) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	17,122,274	14,480,922	10,727,142
Unvested RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	6,698,858	5,253,347	2,868,407
Vested and Unvested Options
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	10,336,634	9,200,337	7,832,386
ESPP Share Purchase Rights
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share	86,782	27,238	26,349

Financial Instruments - Summary

Financial Instruments - Summary of Estimated Fair Value and Related Valuation Input Hierarchy of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Schedule of Available-for-sale Securities [Line Items]
Total Fair Value	$ 237,002	$ 369,472
Fair Value, Measurements, Recurring
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	239,069	369,840
Total Unrealized Gain	7	8
Total Unrealized Loss	(2,074)	(376)
Total Fair Value	237,002	369,472
Fair Value, Measurements, Recurring | Money Market Funds | Level 1
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	78,033	89,738
Total Unrealized Gain	0	0
Total Unrealized Loss	0	0
Total Fair Value	78,033	89,738
Fair Value, Measurements, Recurring | U.S. Treasury Obligations | Level 2
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	63,013	111,832
Total Unrealized Gain	3	1
Total Unrealized Loss	(394)	(138)
Total Fair Value	62,622	111,695
Fair Value, Measurements, Recurring | Government Agency Obligations | Level 2
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	8,086	21,346
Total Unrealized Gain	0	0
Total Unrealized Loss	(48)	(23)
Total Fair Value	8,038	21,323
Fair Value, Measurements, Recurring | Corporate Debt Obligations | Level 2
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	82,598	99,757
Total Unrealized Gain	4	6
Total Unrealized Loss	(1,513)	(190)
Total Fair Value	81,089	99,573
Fair Value, Measurements, Recurring | Commercial Paper | Level 2
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	996	36,993
Total Unrealized Gain	0	0
Total Unrealized Loss	0	0
Total Fair Value	996	36,993
Fair Value, Measurements, Recurring | Asset-Backed Securities | Level 2
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	6,343	10,174
Total Unrealized Gain	0	1
Total Unrealized Loss	(119)	(25)
Total Fair Value	6,224	10,150
Fair Value, Measurements, Recurring | Amounts Classified As Cash Equivalents
Schedule of Available-for-sale Securities [Line Items]
Total Fair Value	87,125
Total Amortized Cost	(87,122)	(104,488)
Total Unrealized Gain	3	0
Total Unrealized Loss	0	0
Total Fair Value		(104,488)
Fair Value, Measurements, Recurring | Amounts Classified As Short-Term Investments
Schedule of Available-for-sale Securities [Line Items]
Total Amortized Cost	151,947	265,352
Total Unrealized Gain	4	8
Total Unrealized Loss	(2,074)	(376)
Total Fair Value	$ 149,877	$ 264,984

Financial Instruments - Amortiz

Financial Instruments - Amortized Cost and Fair Value of Available-for-Sale Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost
Maturing within one year, Amortized cost	$ 202,323	$ 278,457
Maturing in one to five years, Amortized cost	36,746	91,383
Total available-for-sale securities, Amortized cost	239,069	369,840
Estimated Fair value
Maturing within one year, Estimated fair value	201,359	278,354
Maturing in one to five years, Estimated fair value	35,643	91,118
Total available-for-sale securities, Estimated fair value	$ 237,002	$ 369,472

Financial Instruments - Additio

Financial Instruments - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Financial Instruments Disclosure [Abstract]
Accrued interest receivable	$ 800,000	$ 800,000
Write off, of accrued interest receivable	$ 0	$ 0	$ 0

Financial Instruments - Reconci

Financial Instruments - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Financial Instruments Disclosure [Abstract]
Cash and cash equivalents	$ 92,942	$ 106,084
Restricted cash	146	194
Restricted cash - long-term	0	1,200
Total cash, cash equivalents and restricted cash	$ 93,088	$ 107,478	$ 201,798	$ 75,711

Property and Equipment - Schedu

Property and Equipment - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 18,722	$ 82,518
Less: accumulated depreciation and amortization	(12,422)	(28,738)
Property and equipment, net	6,300	53,780
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	875	50,142
Machinery and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	572	5,228
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,297	2,518
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 32	$ 6,325

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment, Net, by Type [Abstract]
Depreciation and amortization expense	$ 5,653	$ 9,345	$ 8,332

Out-license Agreements - Additi

Out-license Agreements - Additional Information (Detail) - USD ($) $ in Thousands		1 Months Ended				3 Months Ended	12 Months Ended
	Oct. 31, 2021	Sep. 30, 2022	Jan. 31, 2022	Oct. 31, 2021	Mar. 31, 2021	Jun. 30, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Aug. 02, 2022
License, Collaboration and Manufacturing Agreements [Line Items]
License and collaboration revenue							$ 63,573	$ 20,340	$ 0
Deferred revenue							0
Development or sales-based milestone payments earned or received							0
Bayer License Agreement
License, Collaboration and Manufacturing Agreements [Line Items]
Upfront cash payment received									45,000
Additional upfront reimbursement payment for research and process development									15,000
Determined upfront payment for license in order to evaluate transaction price									45,000
Determined research and process development activities in order to evaluate transaction price									15,000
Determined additional specified translational activities in order to evaluate transaction price									$ 5,000
Determined fee constituted entire consideration included in transaction price							13,100
Bayer Technology Transfer Agreement
License, Collaboration and Manufacturing Agreements [Line Items]
License Agreement Amount Invoiced Percentage			40%			20%
License Agreement Invoiced Amount			$ 6,100			$ 3,100
License agreement total fee					$ 15,300	$ 15,300
Bayer Manufacturing Agreement
License, Collaboration and Manufacturing Agreements [Line Items]
Estimated Supply Price Amount Invoiced					$ 6,600
License Agreement Percentage O F Estimated Supply Price To Be Invoiced Upon Delivery					50%
Invoiced Upon Written Acceptance Of Binding Purchase Order Percentage					50%
Manufacturing services					$ 13,100
Liabilities Subject To Compromise Early Contract Termination Fees										$ 4,200
License and collaboration revenue							61,800	19,800
Deferred revenue								$ 51,500
Bayer Agreements
License, Collaboration and Manufacturing Agreements [Line Items]
License and collaboration revenue							61,800
Pierre Fabre Commercialization Agreement
License, Collaboration and Manufacturing Agreements [Line Items]
Upfront cash payment received				$ 45,000
Royalty eligible to receive term after first commercial sale	12 years
License and collaboration revenue							1,800
Deferred revenue							85,000
Development or sales-based milestone payments earned or received							$ 40,000
Years of manufacturing and supplying cost							7 years
Determined upfront payment constituted entire consideration included in transaction price							$ 45,000
Payment exchange reduction Amount		$ 30,000
Milestone payments							40,000
Pierre Fabre Commercialization Agreement | Current Liabilities
License, Collaboration and Manufacturing Agreements [Line Items]
Deferred revenue							8,000
Pierre Fabre Commercialization Agreement | Long-Term Liabilities
License, Collaboration and Manufacturing Agreements [Line Items]
Deferred revenue							$ 77,000
Pierre Fabre Commercialization Agreement | Maximum
License, Collaboration and Manufacturing Agreements [Line Items]
Aggregate milestone payments entitle to receive upon achieving certain regulatory and commercial milestones	$ 308,000			$ 308,000

Liability Related to the Sale_3

Liability Related to the Sale of Future Revenues - Schedule of liability related to the sale of future royalties (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Liability for Future Policy Benefit, after Reinsurance [Abstract]
Liability related to sale of future royalties, beginning balance	$ 0
Proceeds from sale of future royalties, gross	31,000
Proceeds From Sale of Future Royalties,Net	30,605	$ 0	$ 0
Less payments made	368
Liability related to sale of future royalties, ending balance	$ 30,237	$ 0

Liability Related to the Sale_4

Liability Related to the Sale of Future Revenues (Additional Information) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Deferred Revenue Arrangement [Line Items]
Payments to Acquire Lease Receivables	$ 31,000
Gross Proceeds from HCR at an initial funding	31,000
Proceeds from sale of future royalties, gross	31,000
Liability related to sale of future royalties	30,237	$ 0
Net of transaction costs	400
Cash Payment	$ 9,000
Maximum [Member]
Deferred Revenue Arrangement [Line Items]
Received tiered royalties on net sales	250%
Minimum [Member]
Deferred Revenue Arrangement [Line Items]
Received tiered royalties on net sales	185%
HealthCare Royalty Partners [Member]
Deferred Revenue Arrangement [Line Items]
Liability related to sale of future royalties	$ 9,000

Sale of ATOM Facility - Schedul

Sale of ATOM Facility - Schedule of assets and gain sales (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Discontinued Operations and Disposal Groups [Abstract]
Net proceeds from sale of ATOM Facility	$ 94,765
Other current assets	190
Property and equipment, net	44,299
Other assets	39
Less: Assets sold	44,528
Gain on sale of ATOM Facility	$ 50,237

Sale of ATOM Facility - Additio

Sale of ATOM Facility - Additional Information (Details) - USD ($) $ in Millions		12 Months Ended
	Apr. 04, 2022	Dec. 31, 2022	Jan. 31, 2022
Discontinued Operations and Disposal Groups [Abstract]
Cash consideration pursuant to asset purchase agreement	$ 94.8		$ 100
Proceeds from transaction cost	$ 4.6
Impairment loss		$ 50.2

Leases - Additional Information

Leases - Additional Information (Details) $ in Millions		1 Months Ended	12 Months Ended
	Feb. 15, 2018 ft²	Mar. 31, 2021 ft²	Dec. 31, 2022	Dec. 31, 2021 USD ($)
Lessee, Lease, Description [Line Items]
Lease Option To Extend Additional Term		5 years
South San Francisco California [Member]
Lessee, Lease, Description [Line Items]
Lease Expiration Date				May 31, 2025
South San Francisco California [Member] | Letter of Credit [Member]
Lessee, Lease, Description [Line Items]
Restricted Cash and Cash Equivalents | $				$ 0.1
Thousand Oaks California [Member]
Lessee, Lease, Description [Line Items]
Lease Agreement Area Of Office Lab And Warehouse Space		33,659
Lessee, Finance Lease, Term of Contract	15 years	10 years 6 months
Lessee Operating Lease Percentage Of Annual Increase In Base Rent		3%
Lease Agreement Area Of Office Lab And Manufacturing Space	90,580
Lease Commencement Date	Feb. 15, 2018
MSA [Member] | Freezers [Member] | Embedded Leases [Member]
Lessee, Lease, Description [Line Items]
Lease Option To Extend Additional Term			5 years

Leases - Schedule of Maturities

Leases - Schedule of Maturities of Lease Liabilities Under Operating and Finance Leases (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Operating leases, 2023	$ 19,158
Operating leases, 2024	18,035
Operating leases, 2025	17,880
Operating leases, 2026	16,557
Operating leases, 2027	5,631
Operating leases, Thereafter	15,778
Operating leases, Total minimum payments	93,039
Less: amount representing interest	(22,169)
Operating Lease, Liability	70,870
Other current liabilities	12,806	$ 2,582
Operating lease liabilities - long-term	58,064	25,518
Finance leases, 2023	1,339
Finance leases, 2024	1,242
Finance leases, 2025	1,263
Finance leases, 2026	1,285
Finance leases, 2027	436
Finance leases, Thereafter	0
Finance leases, Total minimum payments	5,565
Less: amount representing interest	(1,088)
Finance Lease, Liability	4,477
Other current liabilities	834	$ 171
Finance Lease Other Long Term Liabilities	$ 3,643

Leases - Components of Lease Co

Leases - Components of Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating lease cost:
Operating lease cost	$ 14,245	$ 3,827	$ 3,020
Short-term lease cost	386	836	987
Total operating lease cost	14,631	4,663	4,007
Finance lease cost:
Amortization expense	872	244	389
Interest on lease liabilities	373	29	60
Total finance lease cost	$ 1,245	$ 273	$ 449

Leases - Summary of Other Infor

Leases - Summary of Other Information Related to Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows for operating leases	$ 13,417	$ 3,738	$ 2,878
Operating cash flows for finance leases	335	32	62
Financing cash flows for finance leases	518	254	389
Operating lease assets obtained in exchange for lease obligations:	50,779	13,427	0
Finance lease assets obtained in exchange for lease obligations:	4,795	0	281
Non-cash increase to operating lease assets due to remeasurement of lease liabilities:	$ 0	$ 1,760	$ 639
Weighted Average Remaining Lease Term
Operating leases	5 years 10 months 24 days	9 years 2 months 12 days	9 years 4 months 24 days
Finance leases	4 years 2 months 12 days	1 year	1 year 8 months 12 days
Weighted Average Discount Rate
Operating leases	9.90%	9.60%	10.30%
Finance leases	10.40%	9.70%	9.70%

Restructuring - Summarizes of f

Restructuring - Summarizes of future termination benefit payments (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$ 5,964
Research and Development Expense [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	2,544
General and Administrative Expense [Member]
Restructuring Cost and Reserve [Line Items]
Total restructuring charges	$ 3,420

Restructuring - Restructuring o

Restructuring - Restructuring of Labiality Activity (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)
Restructuring and Related Activities [Abstract]
Liability balance, beginning balance	$ 0
Charges	5,964
Cash payments	(4,419)
Liability balance, ending balance	$ 1,545

Restructuring - Additional Info

Restructuring - Additional Information (Details) - USD ($) $ in Millions	Dec. 31, 2022	Aug. 31, 2022	Aug. 08, 2022
Restructuring and Related Activities [Abstract]
Reduction in current workforce percentage		20%	20%
Supplemental unemployment benefits, severance benefits		$ 6	$ 6
Accrued expense restructuring	$ 1.5

Commitments And Contingencies -

Commitments And Contingencies - Additional Information (Details) - USD ($) $ in Millions		12 Months Ended
	Apr. 04, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Contractual obligations due to Bayer, MSK and QIMR		$ 0	$ 0
Minimum Commitments Expense		14.2	0	$ 0
Accrued termination charges		0	0
Liabilities related to indemnification agreements		0	0
Research and Development costs related to minimum purchase commitments		$ 9.2	$ 0
Fujifilm Master Services and Supply Agreement
Loss Contingencies [Line Items]
Supply agreement maximum extension term	10 years

Commitment and Contingencies -

Commitment and Contingencies - Schedule of Contract Services with FDB under Fujifilm MSA Minimum Amount Set Forth (Details) $ in Thousands	Dec. 31, 2022 USD ($)
Commitments and Contingencies Disclosure [Abstract]
2023	$ 19,420
2024	14,085
2025	13,308
2026	9,605
2027	3,388
Total	$ 59,806

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details) - USD ($)		1 Months Ended	3 Months Ended	12 Months Ended
	Apr. 25, 2022	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jul. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Authorized capital stock				520,000,000
Common stock, par value				$ 0.0001	$ 0.0001
Common stock, shares authorized				500,000,000	500,000,000
Preferred stock, par value				$ 0.0001
Preferred stock, shares authorized				20,000,000
Preferred stock, shares outstanding				0	0
Shares of common stock, reserved for issuance				24,649,033
Common stock, shares exercised				15,989	246,867	268,938
Option intrinsic value, exercised				$ 100,000	$ 800,000	$ 1,000,000
Net tax benefits related to exercised options				0
Estimated fair value of stock option, vested				23,200,000	26,600,000	29,400,000
Stock-based compensation expense				53,838,000	$ 53,865,000	$ 51,351,000
Common Stock Value Remained Available To Be Sold				$ 55,900,000
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average grant date fair value per share				$ 8.26	$ 16.42	$ 12.19
Estimated fair value, vested in period				$ 34,400,000	$ 27,100,000	$ 23,600,000
Unrecognized stock-based compensation expense				$ 63,500,000
Unrecognized stock-based compensation weighted average recognition period				2 years 6 months
Aggregate intrinsic value				$ 22,000,000
Restricted stock units, settled				2,247,296	1,553,893
RSU settlements, net of shares withheld, shares				114,444	154,341
Restricted stock units withheld for tax obligations				43,524	61,385
Restricted stock units withheld for tax obligations, value				$ 600,000	$ 1,200,000
Restricted Stock Units (RSUs) | From Date Of Grant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation, vesting period				4 years
Employees And Non Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation, vesting period				4 years
Vested and Unvested Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock-based compensation weighted average recognition period				2 years 4 months 24 days	2 years 6 months
Unrecognized stock-based compensation				$ 29,200,000
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual increase in EIP/ESPP, subject to other limitations				5%
Shares of common stock, reserved for issuance				18,781,047
Common stock, shares available for future grant				4,702,072
Outstanding options and RSUs				14,078,975
Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares of common stock, reserved for issuance				5,191,916
Common stock, shares available for future grant				1,916,728
Outstanding options and RSUs				3,275,188
Additional shares of common stock, reserved for issuance				1,500,000
2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of employees purchase price of common stock				85%
Shares of common stock, reserved for issuance				676,070
Unrecognized stock-based compensation expense				$ 400,000
Stock-based compensation expense				$ 1,100,000	$ 1,700,000	$ 1,800,000
Shares purchased				417,081,000	319,190	282,514
Aggregate number of shares authorized				2,048,280
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of employees purchase price of common stock				100%
Minimum | Employees And Non Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted description terms				the exercise price of an option granted to a 10% shareholder cannot be less than 110% of the fair value of the shares on the date of grant. The estimated fair value of the shares is generally equal to the closing market price of the Company’s common stock on the measurement date. Options granted generally vest over four years and expire in seven to ten years.
Share based compensation award expiration period				7 years
Maximum | Employees And Non Employees
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation award expiration period				10 years
Maximum | 2014 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual increase in EIP/ESPP, subject to other limitations				1%
Maximum increase in number of shares available for issuance				230,769
Underwritten Public Offering
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued		5,102,041	12,633,039
Shares issued, price per share		$ 24.50	$ 11.32			$ 24.50
Proceeds from sale of common stock, gross		$ 175,000,000	$ 201,800,000
Proceeds from sale of common stock, net		$ 164,300,000	$ 189,300,000
Option price to purchase shares			$ 11.32
Underwritten Public Offering | 2019 Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Warrants outstanding				2,888,526
Underwritten Public Offering | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional shares of our common stock			2,325,000
Underwritten Public Offering | Warrant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of warrants issued		2,040,816	2,866,961			2,040,816	2,945,026
Warrant, price per share		$ 24.4999	$ 11.3199			$ 24.4999
Number of securities called by each warrant							1
Warrants, exercise price							$ 0.0001
Warrants, term	7 years
Maximum ownership Percentage	9.99%
Underwritten Public Offering | Warrant | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Prior notice period	61 days
Underwritten Public Offering | Warrant | Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum ownership Percentage	19.99%
At The Market Offering | Cowen
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares issued				1,618,672	6,240,601
Proceeds from sale of common stock, gross				$ 22,400,000	$ 101,300,000
Proceeds from sale of common stock, net				22,000,000	$ 98,900,000
Common stock aggregate offering price				$ 100,000,000
Percentage of commission to be paid on gross sales proceeds of common stock sold				3%
Common stock average price				$ 13.84	$ 16.23

Stockholders' Equity - Summary

Stockholders' Equity - Summary of RSU Activity (Details) - Unvested RSUs - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares, Outstanding as of December 31, 2021	5,592,358
Shares, Granted	5,947,417
Shares, Forfeited	(2,583,871)
Shares, Vested	(2,247,296)
Shares, Outstanding as of December 31, 2022	6,708,608	5,592,358
Weighted Average Grant Date Fair Value, Outstanding as of December 31, 2021	$ 16.22
Weighted Average Grant Date Fair Value, Granted	8.26	$ 16.42	$ 12.19
Weighted Average Grant Date Fair Value, Forfeited	13.27
Weighted Average Grant Date Fair Value, Vested	15.29
Weighted Average Grant Date Fair Value, Outstanding as of December 31, 2022	$ 10.61	$ 16.22

Stockholders' Equity - Summar_2

Stockholders' Equity - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted, Shares	3,615,971	2,643,378	2,641,125
Exercised, Shares	(15,989)	(246,867)	(268,938)
Outstanding, Weighted Average Remaining Contractual Term	6 years 4 months 24 days
Weighted average remaining contractual term ending balance	6 years 4 months 24 days
Stock options vested and expected to vest, Weighted Average Remaining Contractual Term	6 years 4 months 24 days
Exercisable, Weighted Average Remaining Contractual Term	4 years 8 months 12 days
2014 EIP and Inducement Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding, Shares, beginning balance	9,219,837
Granted, Shares	3,615,971
Exercised, Shares	(15,989)
Forfeited or expired, Shares	(2,174,264)
Outstanding, Shares, ending balance	10,645,555	9,219,837
Vested and expected to vest, Shares	10,645,555
Exercisable, Shares	6,061,634
Outstanding, Weighted Average Exercise Price, beginning balance	$ 20.81
Granted, Weighted Average Exercise Price	9.06
Exercised, Weighted Average Exercise Price	8.96
Forfeited or expired, Weighted Average Exercise price	20.62
Outstanding, Weighted Average Exercise Price, ending balance	16.88	$ 20.81
Stock options vested and expected to vest, Weighted Average Exercise Price	16.88
Exercisable, Weighted Average Exercise Price	$ 21.21
Outstanding, Weighted Average Remaining Contractual Term		6 years 4 months 24 days
Weighted average remaining contractual term ending balance		6 years 4 months 24 days
Aggregate intrinsic value	$ 42	$ 12,810
Vested and expected to vest, Aggregate Intrinsic Value	42
Exercisable, Aggregate Intrinsic Value	$ 0

Stockholders' Equity - Summar_3

Stockholders' Equity - Summary of Estimated Weighted-Average Assumptions (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-Based Payment Arrangement [Abstract]
Expected term (years)	6 years	6 years	6 years
Expected volatility	73.20%	75.90%	76.80%
Risk-free interest rate	2.10%	0.90%	0.80%
Expected dividend yield	0%	0%	0%
Weighted-average estimated grant date fair value per share	$ 5.88	$ 10.52	$ 7.96
Options granted	3,615,971	2,643,378	2,641,125
Total estimated grant date fair value	$ 21,261,909	$ 27,808,000	$ 21,023,000

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Common Stock Reserved for Future Issuance Under Equity Incentive Plans (Details)	Dec. 31, 2022 shares
Class Of Stock [Line Items]
Total reserved shares of common stock	24,649,033
2014 Equity Incentive Plan
Class Of Stock [Line Items]
Total reserved shares of common stock	18,781,047
2018 Inducement Plan
Class Of Stock [Line Items]
Total reserved shares of common stock	5,191,916
2014 Employee Stock Purchase Plan
Class Of Stock [Line Items]
Total reserved shares of common stock	676,070

Stockholders' Equity - Schedu_2

Stockholders' Equity - Schedule of Stock-based Compensation Related to Stock Awards (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 53,838	$ 53,865	$ 51,351
Research and development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	31,363	32,063	31,527
General and administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 22,475	$ 21,802	$ 19,824

Income Taxes - Losses Before Pr

Income Taxes - Losses Before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
United States	$ (228,395)	$ (340,301)	$ (306,758)
Foreign	105	206	153
Loss before provision for income taxes	$ (228,290)	$ (340,095)	$ (306,605)

Income Taxes - Components of Pr

Income Taxes - Components of Provision for (Benefit from) Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current provision for income taxes:
State	$ 0	$ 4	$ 2
Foreign	12	42	13
Total current provision for income taxes	$ 12	$ 46	$ 15

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Statutory Tax Rates to Effective Tax Rates (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal income taxes at statutory rate	21%	21%	21%
Research tax credits	7.80%	0%	0%
Stock-based compensation	(3.80%)	(2.00%)	(2.40%)
Other	(0.20%)	(0.30%)	0.20%
Change in valuation allowance	(24.80%)	(18.70%)	(18.80%)
Effective tax rate	0%	0%	0%

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets:
Net operating loss carryforwards	$ 302,591	$ 308,997
Capitalized research expenses	50,522	10,499
Tax credit carryforwards	19,427	1,580
Stock-based compensation	19,201	24,181
Deferred Revenue	10,069	12,133
Operating lease liabilities	15,857	7,972
License fees	6,877	8,716
Other	13,169	9,414
Total deferred tax assets	437,713	383,492
Valuation allowance	(422,493)	(376,071)
Total deferred tax assets	15,220	7,421
Deferred tax liabilities:
Operating lease assets	(15,220)	(7,421)
Total deferred tax liabilities	(15,220)	(7,421)
Net deferred tax assets (liabilities)	$ 0	$ 0

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes [Line Items]
Change in capitalized expenses	$ 43,700
Tax credit carryforward, change in amount	17,800
Increase in valuation allowance tax	46,400
Net operating loss carryforwards, federal	1,000,000
Research and development tax credit carryforwards	$ 106,900
Research and development tax credit carryforwards, expiration year	2035
Tax credit carryforwards	$ 19,427	$ 1,580
Accrued interest and penalties	0	0
Unrecognized tax benefits	$ 150,965	$ 144,067	$ 110,601	$ 86,000
Domestic
Income Taxes [Line Items]
Capitalized expenses, amortization period	5 years
Net operating loss carryforwards subject to expiration	$ 22,600
Net tax operating losses, expiration	begin to expire in 2036
Research and development tax credit carryforwards	$ 24,000
Research and development tax credit carryforwards, expiration year	2032
Operating loss carryforwards	$ 42,700
State
Income Taxes [Line Items]
Net tax operating losses, expiration	begin to expire in 2030
Net operating loss carryforwards not subject to expiration	$ 38,000
Net operating loss carryforwards, state	$ 1,300,000
Foreign
Income Taxes [Line Items]
Capitalized expenses, amortization period	15 years
Tax credit carryforwards	$ 2,000
Tax credit carryforwards, expiration year	2025

Income Taxes - Reconciliation_2

Income Taxes - Reconciliation of Beginning and Ending Amount of Gross Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Beginning Balance	$ 144,067	$ 110,601	$ 86,000
Gross increases for tax positions related to current year	7,683	28,171	24,648
Gross increases for tax positions related to prior year	0	5,295	0
Gross decreases for tax positions related to prior year	(785)	0	(47)
Ending Balance	$ 150,965	$ 144,067	$ 110,601

Supplemental Balance Sheet In_3

Supplemental Balance Sheet Information - Schedule of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Supplemental Balance Sheet Information [Abstract]
Raw Materials	$ 1,214	$ 0
Work-in-process	372	0
Total inventories	$ 1,586	$ 0

Supplemental Balance Sheet In_4

Supplemental Balance Sheet Information - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	$ 18,722	$ 82,518
Less: accumulated depreciation and amortization	(12,422)	(28,738)
Property and equipment, net	6,300	53,780
Leasehold Improvements [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	875	50,142
Lab Equipment [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	14,797	14,060
Machinery and Equipment [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	572	5,228
Computer Equipment and Software [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	1,149	4,245
Furniture and Fixtures [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	1,297	2,518
Construction in Progress [Member]
Supplemental Balance Sheet Information [Line Items]
Property and equipment, gross	$ 32	$ 6,325

Supplemental Balance Sheet In_5

Supplemental Balance Sheet Information - Schedule of Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Supplemental Balance Sheet Information [Abstract]
Accrued operating expenses	$ 7,435	$ 5,960
Current portion of operating lease liabilities	$ 12,806	$ 2,582
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Liabilities, Current	Liabilities, Current
Current portion of finance lease liabilities	$ 834	$ 171
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Liabilities, Current	Liabilities, Current
Other accrued liabilities	$ 319	$ 344
Total other current liabilities	$ 21,394	$ 9,057

Supplemental Balance Sheet In_6

Supplemental Balance Sheet Information - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Supplemental Balance Sheet Information [Abstract]
Depreciation and amortization expense	$ 5,653	$ 9,345	$ 8,332