CytomX Therapeutics (CTMX) 10-Q 4 Aug 22 2022 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2022	Jul. 29, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q2
Trading Symbol	CTMX
Entity Registrant Name	CytomX Therapeutics, Inc.
Entity Central Index Key	0001501989
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity File Number	001-37587
Entity Tax Identification Number	27-3521219
Entity Address, Address Line One	151 Oyster Point Blvd.
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94080
City Area Code	650
Local Phone Number	515-3185
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, $0.00001 par value per share
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		65,950,242

CONDENSED BALANCE SHEETS

CONDENSED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 129,290	$ 205,530	[1]
Short-term investments	98,875	99,696	[1]
Accounts receivable	1,014	790	[1]
Prepaid expenses and other current assets	3,591	4,285	[1]
Total current assets	232,770	310,301	[1]
Property and equipment, net	5,915	5,960	[1]
Intangible assets, net	948	1,021	[1]
Goodwill	949	949	[1]
Restricted cash	917	917	[1]
Operating lease right-of-use asset	17,692	19,362	[1]
Other assets	895	901	[1]
Total assets	260,086	339,411	[1]
Current liabilities:
Accounts payable	1,920	2,818	[1]
Accrued liabilities	31,732	34,236	[1]
Deferred revenue, current portion	65,787	69,262	[1]
Total current liabilities	99,439	106,316	[1]
Deferred revenue, net of current portion	95,863	125,660	[1]
Operating lease liabilities - long term	16,076	18,056	[1]
Total liabilities	211,378	250,032	[1]
Commitments and contingencies (Note 8)
Stockholders' equity:
Common stock, $0.00001 par value; 150,000,000 shares authorized and 65,756,492 and 65,392,758 shares issued and outstanding at June 30, 2022 and December 31, 2021, respectively	1	1	[1]
Additional paid-in capital	631,662	623,344	[1]
Accumulated other comprehensive loss	(1,162)	(242)	[1]
Accumulated deficit	(581,793)	(533,724)	[1]
Total stockholders' equity	48,708	89,379	[1]
Total liabilities and stockholders' equity	260,086	339,411	[1]
Convertible Preferred Stock
Stockholders' equity:
Convertible preferred stock, $0.00001 par value; 10,000,000 shares authorized and no shares issued and outstanding at June 30, 2022 and December 31, 2021.	$ 0	$ 0	[1]
[1] The condensed balance sheet as of December 31, 2021 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2021.

CONDENSED BALANCE SHEETS (Paren

CONDENSED BALANCE SHEETS (Parenthetical) - $ / shares	Jun. 30, 2022	Dec. 31, 2021
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	65,756,492	65,392,758
Common stock, shares outstanding	65,756,492	65,392,758
Convertible Preferred Stock
Convertible Preferred stock, par value	$ 0.00001	$ 0.00001
Convertible Preferred stock, shares authorized	10,000,000	10,000,000
Convertible Preferred stock, shares issued	0	0
Convertible Preferred stock, shares outstanding	0	0

CONDENSED STATEMENTS OF OPERATI

CONDENSED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Revenues	$ 18,165	$ 16,288	$ 35,302	$ 32,259
Type of Revenue [Extensible List]	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Operating expenses:
Research and development	$ 31,159	$ 26,100	$ 61,718	$ 48,472
General and administrative	11,748	9,393	22,292	18,619
Total operating expenses	42,907	35,493	84,010	67,091
Loss from operations	(24,742)	(19,205)	(48,708)	(34,832)
Interest income	262	44	330	112
Other income (expense), net	296	(82)	309	(77)
Net loss	(24,184)	(19,243)	(48,069)	(34,797)
Other comprehensive loss
Unrealized gain (loss) on investments, net of tax	(243)	58	(920)	62
Comprehensive loss	$ (24,427)	$ (19,185)	$ (48,989)	$ (34,735)
Net loss per share, Basic	$ (0.37)	$ (0.30)	$ (0.73)	$ (0.55)
Net loss per share, Diluted	$ (0.37)	$ (0.30)	$ (0.73)	$ (0.55)
Shares used in computing net loss per share, Basic	65,542,762	65,055,998	65,468,638	63,023,349
Shares used in computing net loss per share, Diluted	65,542,762	65,055,998	65,468,638	63,023,349

CONDENSED STATEMENTS OF STOCKHO

CONDENSED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total		Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance at Dec. 31, 2020	$ 49,803		$ 1	$ 499,964	$ (47)	$ (450,115)
Beginning balance, shares at Dec. 31, 2020			48,251,819
Issuance of common stock in follow-on offering, net of issuance costs	107,712			107,712
Issuance of common stock in follow-on offering, net of issuance costs, shares			16,428,571
Exercise of stock options	1,023			1,023
Exercise of stock options, shares			322,507
Stock-based compensation	3,034			3,034
Other comprehensive income (loss)	4				4
Net loss	(15,554)					(15,554)
Ending balance at Mar. 31, 2021	146,022		$ 1	611,733	(43)	(465,669)
Ending balance, shares at Mar. 31, 2021			65,002,897
Beginning balance at Dec. 31, 2020	49,803		$ 1	499,964	(47)	(450,115)
Beginning balance, shares at Dec. 31, 2020			48,251,819
Other comprehensive income (loss)	62
Net loss	(34,797)
Ending balance at Jun. 30, 2021	130,953		$ 1	615,849	15	(484,912)
Ending balance, shares at Jun. 30, 2021			65,157,003
Beginning balance at Mar. 31, 2021	146,022		$ 1	611,733	(43)	(465,669)
Beginning balance, shares at Mar. 31, 2021			65,002,897
Exercise of stock options	173			173
Exercise of stock options, shares			68,971
Issuance of common stock under the ESPP	518			518
Issuance of common stock under the ESPP, shares			85,135
Stock-based compensation	3,425			3,425
Other comprehensive income (loss)	58				58
Net loss	(19,243)					(19,243)
Ending balance at Jun. 30, 2021	130,953		$ 1	615,849	15	(484,912)
Ending balance, shares at Jun. 30, 2021			65,157,003
Beginning balance at Dec. 31, 2021	89,379	[1]	$ 1	623,344	(242)	(533,724)
Beginning balance, shares at Dec. 31, 2021			65,392,758
Exercise of stock options	7			7
Exercise of stock options, shares			5,597
Stock-based compensation	3,370			3,370
Other comprehensive income (loss)	(677)				(677)
Net loss	(23,885)					(23,885)
Ending balance at Mar. 31, 2022	68,194		$ 1	626,721	(919)	(557,609)
Ending balance, shares at Mar. 31, 2022			65,398,355
Beginning balance at Dec. 31, 2021	$ 89,379	[1]	$ 1	623,344	(242)	(533,724)
Beginning balance, shares at Dec. 31, 2021			65,392,758
Exercise of stock options, shares	100,990
Other comprehensive income (loss)	$ (920)
Net loss	(48,069)
Ending balance at Jun. 30, 2022	48,708		$ 1	631,662	(1,162)	(581,793)
Ending balance, shares at Jun. 30, 2022			65,756,492
Beginning balance at Mar. 31, 2022	68,194		$ 1	626,721	(919)	(557,609)
Beginning balance, shares at Mar. 31, 2022			65,398,355
Exercise of stock options	91			91
Exercise of stock options, shares			95,393
Issuance of common stock under the ESPP	360			360
Issuance of common stock under the ESPP, shares			262,744
Stock-based compensation	4,490			4,490
Other comprehensive income (loss)	(243)				(243)
Net loss	(24,184)					(24,184)
Ending balance at Jun. 30, 2022	$ 48,708		$ 1	$ 631,662	$ (1,162)	$ (581,793)
Ending balance, shares at Jun. 30, 2022			65,756,492
[1] The condensed balance sheet as of December 31, 2021 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2021.

CONDENSED STATEMENTS OF CASH FL

CONDENSED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities:
Net loss	$ (48,069)	$ (34,797)
Adjustments to reconcile net loss to net cash used in operating activities:
Amortization of intangible assets	73	73
Depreciation and amortization	1,139	1,278
Amortization of premium (accretion of discounts) on investments	(33)	281
Stock-based compensation expense	7,860	6,459
Non-cash lease expense	1,670	1,534
Changes in operating assets and liabilities
Accounts receivable	(290)	(133)
Prepaid expenses and other current assets	694	3,199
Other assets	6	1,271
Accounts payable	(844)	(1,173)
Accrued liabilities and other long-term liabilities	(4,484)	(5,559)
Deferred revenue	(33,272)	(30,572)
Net cash used in operating activities	(75,550)	(58,139)
Cash flows from investing activities:
Purchases of property and equipment	(1,148)	(1,096)
Purchases of investments	0	(99,898)
Maturities of investments	0	113,994
Net cash provided by (used in) investing Activities	(1,148)	13,000
Cash flows from financing activities:
Proceeds from issuance of common stock, net of issuance costs	0	107,712
Proceeds from employee stock purchase plan and exercise of stock options	458	1,714
Net cash provided by financing activities	458	109,426
Net increase (decrease) in cash, cash equivalents and restricted cash	(76,240)	64,287
Cash, cash equivalents and restricted cash, beginning of period	206,447	192,776
Cash, cash equivalents and restricted cash, end of period	130,207	257,063
Supplemental disclosures of noncash investing items:
Purchases of property and equipment in accounts payable and accrued liabilities	$ 29	$ 54

Description of the Business

Description of the Business	6 Months Ended
	Jun. 30, 2022
Disclosure Text Block [Abstract]
Description of the Business	1. Description of the Business CytomX Therapeutics, Inc. (the “Company”) is a clinical-stage, oncology-focused biopharmaceutical company dedicated to destroying cancer differently. The Company aims to build a commercial enterprise to maximize its impact on the treatment of cancer. The Company is advancing potential first-in-class and best-in-class antibody-based therapeutics created using its Probody® therapeutic technology platform that could meaningfully improve outcomes for cancer patients. Its proprietary and unique Probody technology platform is designed to enable “conditional activation” of antibody-based drugs in the tumor microenvironment while minimizing drug activity in healthy tissues and in circulation. The Company is located in South San Francisco, California and was incorporated in the state of Delaware in September 2010.

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	2. Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation The accompanying interim condensed financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting. Unaudited Interim Financial Information The accompanying interim condensed financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented. The condensed results of operations for the three and six months ended June 30, 2022 are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. The accompanying condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC. Use of Estimates The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates. Cash, cash equivalents and restricted cash The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed balance sheets that sum to the total of the amounts shown in the condensed statements of cash flows: June 30, 2022 December 31, 2021 June 30, 2021 December 31, 2020 (in thousands) Cash and cash equivalents $ 129,290 $ 205,530 $ 256,146 $ 191,859 Restricted cash - non-current assets 917 917 917 917 Total $ 130,207 $ 206,447 $ 257,063 $ 192,776 Restricted cash represents a standby letter of credit issued pursuant to an office lease. Revenue Recognition The Company’s revenues are primarily derived through its license, research, development and commercialization agreements. The terms of these types of agreements may include (i) licenses for the Company’s technology or programs, (ii) research and development services, and (iii) services or obligations in connection with participation in research or steering committees. Payments to the Company under these arrangements typically include one or more of the following: nonrefundable upfront and license fees, research funding, milestone and other contingent payments to the Company for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory and sales-based events, as well as royalties on sales of any commercialized products. The Company assesses whether the promises in its arrangements with customers are distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to the Company’s intellectual property is distinct from the research and development services or participation on steering committees. The Company’s collaboration and license agreements may include contingent payments related to specified research, development and regulatory milestones. Such milestone payments are typically payable under the collaborations when the collaboration partner claims or selects a target, or initiates or advances a covered product candidate in preclinical or clinical development, upon submission for marketing approval of a covered product with regulatory authorities, or upon receipt of actual marketing approvals of a covered product or for additional indications. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At each reporting date, the Company re-evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price in such period of determination. The Company’s collaboration and license agreements may also include contingent payments related to sales-based milestones. Sales-based milestones are typically payable when annual sales of a covered product reach specified levels. Sales-based milestones are recognized at the later of when the associated performance obligation has been satisfied or when the sales occur. Unlike other contingency payments, such as regulatory milestones, sales-based milestones are not included in the transaction price based on estimates at the inception of the contract; instead, they are included when the sales or usage occur. The transaction price in each arrangement is allocated to the identified performance obligations based on the relative standalone selling price (“SSP”) of each distinct performance obligation, which requires judgment. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of the Company’s licensed technology, the license of such technology is typically combined with research and development services and steering committee participation as one performance obligation. In the event that the Company receives non-cash consideration such as consideration in the form of a research license and research support services from the counterparty, the transaction price of a non-monetary exchange that has commercial substance is estimated based on the fair value of the non-cash consideration received, which may be determined through a valuation analysis. In certain cases, the Company’s performance creates an asset that does not have an alternative use to the customer and the Company has an enforceable right to payment at all times for performance completed to date. In these cases, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. AbbVie Ireland Unlimited Company (“AbbVie”), one of the Company’s collaboration partners, entered into a license agreement with Seagen Inc., formerly Seattle Genetics, Inc. (“SGEN”) to license certain intellectual property rights. As part of the Company’s collaboration agreement with AbbVie, the Company is required to pay SGEN sublicense fees for certain milestone achievements and an annual maintenance fee. These sublicense fees are treated as reductions to the transaction price and combined with the performance obligation to which they relate. Contract Balances Customer payments are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until the Company satisfies its performance obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2022
Earnings Per Share [Abstract]
Net Loss Per Share	3. Net Loss Per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per share is calculated using the weighted-average number of common shares outstanding, plus potential dilutive common stock during the period. Diluted net loss per share is the same as basic net loss per share since the effect of the potentially dilutive securities is anti-dilutive. The following weighted-average outstanding shares of potentially dilutive securities are excluded from the computation of diluted net loss per share for the periods presented, because including them would have been anti-dilutive: Three Months Ended Six Months Ended June 30, June 30, 2022 2021 2022 2021 Options, RSUs and ESPP to purchase common stock 15,226,820 12,117,149 14,888,352 11,837,707

Fair Value Measurements and Inv

Fair Value Measurements and Investments	6 Months Ended
	Jun. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements and Investments	4. Fair Value Measurements and Investments In accordance with Accounting Standards Codification (“ASC”) 820-10, Fair Value Measurements and Disclosures, the Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows: • Level I: Inputs which include quoted prices in active markets for identical assets and liabilities. • Level II: Inputs other than Level I that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. • Level III: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The carrying amounts of the Company’s financial instruments, including restricted cash, accounts receivable, accounts payable and accrued liabilities approximate fair value due to their relatively short maturities. The Company’s financial instruments consist of Level I assets which consist primarily of highly liquid money market funds, some of which are included in restricted cash; and U.S. government bonds that are included in short-term investments. The following tables set forth the fair value of the Company’s investments subject to fair value measurements on a recurring basis and the level of inputs used in such measurements: June 30, 2022 Valuation Amortized Unrealized Unrealized Aggregate (in thousands) Assets Money market funds Level I $ 75,878 $ — $ — $ 75,878 Restricted cash (money market funds) Level I 917 — — 917 U.S. Government bonds Level I 100,037 — ( 1,162 ) 98,875 Total $ 176,832 $ — $ ( 1,162 ) $ 175,670 December 31, 2021 Valuation Amortized Unrealized Unrealized Aggregate (in thousands) Assets Money market funds Level I $ 165,736 $ — $ — $ 165,736 Restricted cash (money market funds) Level I 917 — — 917 U.S. Government bonds Level I 99,938 — ( 242 ) 99,696 Total $ 266,591 $ — $ ( 242 ) $ 266,349 No securities have contractual maturities of greater than twelve months . As of June 30, 2022, the unrealized losses on the Company’s investment in US Government bonds were caused by interest rate changes and were not attributable to credit losses. The remaining contractual terms of those investments are less than a year. The Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before recovery of their amortized cost bases.

Accrued Liabilities

Accrued Liabilities	6 Months Ended
	Jun. 30, 2022
Accrued Liabilities, Current [Abstract]
Accrued Liabilities	5. Accrued Liabilities Accrued liabilities consisted of the following: June 30, December 31, 2022 2021 (in thousands) Research and clinical expenses $ 18,377 $ 18,861 Payroll and related expenses 7,109 9,576 Legal and professional expenses 2,259 1,468 Operating lease liabilities - short term 3,845 3,618 Other accrued expenses 142 713 Total $ 31,732 $ 34,236

Research and Collaboration Agre

Research and Collaboration Agreements	6 Months Ended
	Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Research and Collaboration Agreements	6. Research and Collaboration Agreements The following table summarizes the revenue by collaboration partner: Three Months Ended Six Months Ended June 30, June 30, 2022 2021 2022 2021 (in thousands) (in thousands) AbbVie $ 5,377 $ 2,078 $ 7,804 $ 3,306 Amgen 369 1,874 2,657 4,456 Astellas 5,014 4,931 10,031 9,687 Bristol Myers Squibb 7,405 7,405 14,810 14,810 Total revenue $ 18,165 $ 16,288 $ 35,302 $ 32,259 AbbVie Ireland Unlimited Company In April 2016, the Company and AbbVie entered into two agreements, a CD71 Co-Development and Licensing Agreement (the “CD71 Agreement”) and a Discovery Collaboration and Licensing Agreement (as amended and restated in June 2019, the “Discovery Agreement” and together with the CD71 Agreement the “AbbVie Agreements”). Under the terms of the CD71 Agreement, the Company and AbbVie will co-develop a conditionally activated antibody-drug conjugate (“ADC”) against CD71, with the Company responsible for preclinical and early clinical development. AbbVie will be responsible for later development and commercialization, with global late-stage development costs shared between the two companies. The Company will assume 35 % of the net profits or net losses related to later development and commercialization unless it opts-out. If the Company opts-out from participation of co-development of the CD71 conditionally activated ADC, which includes CX-2029, AbbVie will have sole right and responsibility for the further development, manufacturing and commercialization of such CD71 conditionally activated ADC. Under the CD71 Agreement, the Company received an upfront payment of $ 20.0 million in April 2016, and was eligible to initially receive up to $ 470.0 million in development, regulatory and commercial milestone payments, a 35 % profit split on U.S. sales, and royalties on ex-U.S. sales at percentages in the high teens to low twenties if the Company participates in the co-development of the CD71 conditionally activated ADC subject to a reversion to a royalty on U.S. sales, and reduction in royalties on ex-U.S. sales, if the Company opts-out from the co-development of the CD71 conditionally activated ADC. The Company’s share of later stage co-development costs for each CD71 conditionally activated ADC is capped, provided that AbbVie may offset the Company’s co-development cost above the capped amounts from future payments such as milestone payments and royalties. Inclusive of payments received in 2017, 2018 and 2020, as of June 30, 2022, the Company has received $ 100.0 million in milestone payments under the CD71 Agreement. Under the terms of the Discovery Agreement, AbbVie receives exclusive worldwide rights to develop and commercialize conditionally activated ADCs against up to two targets, one of which was selected in March 2017. The Company shall perform research services to discover the Probody therapeutics and create conditionally activated ADCs for the nominated collaboration targets. From that point, AbbVie shall have sole right and responsibility for development and commercialization of products comprising or containing such conditionally activated ADCs (“Discovery Licensed Products”). Under the Discovery Agreement, the Company received an upfront payment of $ 10.0 million in April 2016 and subsequently earned an additional $ 10.0 million milestone payment triggered by selection of the second target by AbbVie in June 2019. The Company is also eligible to receive up to $ 265.0 million for each target, in development, regulatory and commercial milestone payments and royalties at percentages in the high single to low teens from commercial sales of any resulting conditionally activated ADCs. The second target was selected under the Discovery Agreement that allows AbbVie to select a target for developing a conditionally activated ADC or a Probody. The Company determined that the remaining potential milestone payments of both agreements, if recognized, are probable of significant revenue reversal as their achievement is highly dependent on factors outside the Company’s control. Therefore, these payments continue to be fully constrained and are not included in the transaction price as of June 30, 2022. As of June 30, 2022 and December 31, 2021, deferred revenue related to the CD71 Agreement performance obligation was $ 9.5 million and $ 16.1 million, respectively, and deferred revenue related to the Discovery Agreement performance obligation was $ 4.0 million and $ 5.2 million, respectively. Amgen, Inc. On September 29, 2017, the Company and Amgen, Inc. (“Amgen”) entered into a Collaboration and License Agreement (the “Amgen Agreement”). Pursuant to the Amgen Agreement, the Company received an upfront payment of $ 40.0 million in October 2017. Concurrent with the Amgen Agreement, the Company and Amgen entered into a Share Purchase Agreement pursuant to which Amgen purchased 1,156,069 shares of the Company’s common stock at a price of $ 17.30 per share for total proceeds of $ 20.0 million. In October 2021, CytomX and Amgen executed an amendment to the Amgen Agreement primarily to (1) extend the target selection date for Amgen to select its additional targets for research and development, and (2) reduce the total number of milestone events and increase the total amount of milestone payments for EGFR Products. Under the terms of the Amgen Agreement, as amended, the Company and Amgen will co-develop a conditionally activated T-cell engaging bispecific therapeutic targeting epidermal growth factor receptor (the “EGFR Products”). The Company is responsible for early-stage development of EGFR Products and Amgen will be responsible for late-stage development and commercialization of EGFR Products. Following early-stage development, the Company will have the right to elect to participate financially in the global co-development of EGFR Products with Amgen, during which the Company would bear certain of the worldwide development costs for EGFR Products and Amgen would bear the rest of such costs (the “EGFR Co-Development Option”). If the Company exercises its EGFR Co-Development Option, the Company will share in somewhat less than 50 % of the profit and losses from sales of such EGFR Products in the U.S., subject to certain caps, offsets, and deferrals. If the Company chooses not to exercise its EGFR Co-Development Option, the Company will not bear any costs of later stage development. The Company is also eligible to receive up to $ 460.0 million in development, regulatory, and commercial milestone payments for EGFR Products, and royalties in the low-double-digit to mid-teen percentage of worldwide commercial sales, provided that if the Company exercises its EGFR Co-Development option, it shall receive a profit and loss split of sales in the United States and royalties in the low-double-digit to mid-teen percentage of commercial sales outside of the United States. Amgen also has the right to select a total of up to three targets, including the two additional targets discussed below. The Company and Amgen collaborate in the research and development of conditionally activated T-cell engaging bispecifics products directed against such targets. Amgen has selected one such target (the “Amgen Other Product”). If Amgen exercises its option within a specified period of time, it can select two such additional targets (the “Amgen Option Products” and, together with the Amgen Other Product, the “Amgen Products”). Except with respect to preclinical activities to be conducted by CytomX, Amgen will be responsible, at its expense, for the development, manufacture, and commercialization of all Amgen Products. If Amgen exercises all of its options and advances all three of the Amgen Products, CytomX was initially eligible to receive up to $ 950.0 million in upfront, development, regulatory, and commercial milestones and tiered high single-digit to low-teen percentage royalties. The Company concluded that, at the inception of the agreement, Amgen’s option to select the two additional targets is not a material right and does not represent a performance obligation of the agreement. At the initiation of the collaboration, CytomX had the option to select, from programs specified in the Amgen Agreement, an existing preclinical stage T-cell engaging bispecific product from the Amgen preclinical pipeline. In March 2018, CytomX selected the program. CytomX is responsible, at its expense, for converting this program to a conditionally activated T-cell engaging bispecific product, and thereafter, will be responsible for development, manufacturing, and commercialization of the product (“CytomX Product”). Amgen is eligible to receive up to $ 203.0 million in development, regulatory, and commercial milestone payments for the CytomX Product, and tiered mid-single digit to low double-digit percentage royalties. In January 2022, the IND for the EGFR product (CX-904) was allowed to proceed by the U.S. Food and Drug Administration (“FDA”). As of June 30, 2022 and December 31, 2021, deferred revenue related to the EGFR Products performance obligation was $ 19.6 million and $ 21.8 million, respectively. As of June 30, 2022 and December 31, 2021, deferred revenue related to the Amgen Other Products performance obligation was $ 1.0 million and $ 1.4 million, respectively. Astellas Pharma Inc. The Company and Astellas Pharma, Inc. (“Astellas”) entered into a Collaboration and License Agreement (the “Astellas Agreement”) on March 23, 2020, the effective date, to collaborate on preclinical research activities to discover and develop certain antibody compounds for the treatment of cancer using the Company’s Probody therapeutic technology. Under the terms of the Astellas Agreement, the Company granted Astellas an exclusive, worldwide right to develop and commercialize Probody therapeutics for up to four collaboration targets including one initial target and three additional targets (“Additional Targets”). In addition, Astellas has the right to expand the number of Additional Targets from three up to five (the “Expansion Option”) before the third anniversary of the effective date. Furthermore, for a specified number of targets, at a pre-specified time prior to the initiation of the first pivotal study of a product against such target, the Company may elect to participate in certain development costs and share in the profits generated in the United States with respect to such product (“Cost Share Option”). The Cost Share Option, if exercised, will also provide the option for the Company to co-commercialize such product in the United States. The Company does not consider the Cost Share Option as a performance obligation at the inception of the agreement as the participation is at the Company’s discretion. Pursuant to the Astellas Agreement, the consideration from Astellas is comprised of an upfront fee of $ 80.0 million and contingent payments for development, regulatory and sales milestones of up to an aggregate of approximately $ 1.6 billion. If Astellas exercises its Expansion Option for the two Additional Targets, the Company would be eligible to receive additional upfront and milestone payments aggregating to approximately $ 0.9 billion. The Company is also entitled to tiered royalties from high-single digit to mid-teen percentage royalties from potential future sales. Astellas is responsible for all preclinical research costs incurred by either party as set forth in the preclinical research plan and the Company will receive research and development service fees based on a prescribed full time employee ("FTE") rate. As of June 30, 2022 and December 31, 2021, deferred revenue relating to the Astellas Agreement was $ 43.7 million and $ 51.6 million, respectively. The amount due from Astellas under the Astellas Agreement was $ 1.0 million and $ 0.8 million as of June 30, 2022 and December 31, 2021, respectively. Bristol Myers Squibb Company On May 23, 2014, the Company and Bristol Myers Squibb Company (“Bristol Myers Squibb”) entered into a Collaboration and License Agreement (the “BMS Agreement”) to discover and develop compounds for use in human therapeutics aimed at multiple immuno-oncology targets using the Company’s Probody therapeutic technology. The effective date of the BMS Agreement was July 7, 2014. Under the terms of the BMS Agreement, the Company granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize Probody therapeutics for up to four oncology targets. Bristol Myers Squibb had additional rights to substitute up to two collaboration targets within three years of the effective date of the BMS Agreement. These rights expired in May 2017. Each collaboration target had a two-year research term and the two additional targets had to be nominated by Bristol Myers Squibb within five years of the effective date of the BMS Agreement. The research term for each collaboration target could be extended in one year increments up to three times. Pursuant to the BMS Agreement, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $ 50.0 million, and the Company was initially entitled to receive contingent payments of up to $ 25.0 million for additional targets and up to an aggregate of $ 1,192.0 million for development, regulatory and sales milestones. In addition, the Company was entitled to royalty payments in the mid-single digits to low double-digit percentages from potential future sales. The Company also received research and development service fees based on a prescribed FTE rate that was capped. On March 17, 2017, the Company and Bristol Myers Squibb entered into Amendment Number 1 to Extend Collaboration and License Agreement (“Amendment 1”). Amendment 1 granted Bristol Myers Squibb exclusive worldwide rights to develop and commercialize Probody therapeutics for up to eight additional targets. The effective date of Amendment 1 was April 25, 2017 (“Amendment Effective Date”). Under the terms of Amendment 1, the Company continued to have obligations to Bristol Myers Squibb to discover and conduct preclinical development of Probody therapeutics against any targets they chose to select during the research period under the terms of Amendment 1. Pursuant to Amendment 1, the financial consideration from Bristol Myers Squibb was comprised of an upfront payment of $ 200.0 million and the Company was initially eligible to receive contingent payments for development, regulatory and sales milestones of up to an aggregate of $ 3,586.0 million for the eight targets. The Company was also entitled to tiered mid-single to low double-digit percentage royalties from potential future sales. Amendment 1 did not change the term of the Bristol Myers Squibb’s royalty obligation under the BMS Agreement. Bristol Myers Squibb’s royalty obligation continues on a licensed-product by licensed-product basis until the later of (i) the expiration of the last claim of the licensed patents covering the licensed products in the country, (ii) the twelfth anniversary of the first commercial sale of a licensed product in a country, or (iii) the expiration of any applicable regulatory, pediatric, orphan drug or data exclusivity with respect to such product. The initial transaction price for the BMS Agreement and Amendment 1, collectively, was $ 272.8 million consisting of the upfront fees of $ 250.0 million, research and development service fees of $ 10.8 million and milestone payments received of $ 12.0 million upon the adoption of ASC 606 on January 1, 2018. The Company determined that the remaining potential milestone payments were probable of significant revenue reversal as their achievement was highly dependent on factors outside the Company’s control. Therefore, these payments were fully constrained and were not included in the transaction price upon the adoption of ASC 606 on January 1, 2018. The BMS Agreement represents an obligation to continuously make the Probody therapeutic technology platform available to Bristol Myers Squibb. Therefore, the initial transaction price is recognized over the estimated research service period, which ends on April 25, 2025 . In February 2021, the Company and Bristol Myers Squibb entered into Amendment Number 2 to amend the Collaboration and License Agreement (“Amendment 2”), as amended by Amendment 1. Subsequent to Amendment 2, Bristol Myers Squibb has the exclusive worldwide rights to develop and commercialize Probody therapeutics for up to five oncology targets. Under the terms of Amendment 2, the period for target selection has been extended and the Company will continue to collaborate with Bristol Myers Squibb to discover and conduct preclinical development of Probody therapeutics against targets selected by Bristol Myers Squibb over the estimated research period, which ends in April 2025. Pursuant to Amendment 2, the Company is eligible to receive contingent payments for development, regulatory and sales milestones of up to an aggregate of $ 1,779.0 million. It is also entitled to tiered mid-single to low double-digit percentage of royalties from potential future sales. In addition, the Company will no longer be entitled to receive the research and development service fee as part of the arrangement. The Company reevaluated the remaining potential milestone payments and determined that significant revenue reversal was still probable as the achievement of such milestones was highly dependent on factors outside the Company’s control. As a result, these payments continued to be fully constrained and are not included in the transaction price as of June 30, 2022. As of June 30, 2022 and December 31, 2021, deferred revenue relating to the BMS Agreement was $ 83.9 million and $ 98.8 million, respectively. Contract Liabilities The following table presents changes in the Company’s total contract liabilities during the six months ended June 30, 2022: Balance at Additions Deductions Balance at (in thousands) Contract liabilities: Deferred revenue $ 194,922 $ — $ ( 33,272 ) $ 161,650 The Company expects that the $ 161.7 million of deferred revenue related to the following contracts as of June 30, 2022 will be recognized as revenue as set forth below. However, the timing of revenue recognition could differ from the estimates depending on facts and circumstances impacting the various contracts, including progress of research and development, resources assigned to the contracts by the Company or its collaboration partners or other factors outside of the Company’s control. • The $ 9.5 million of deferred revenue related to the CD71 Agreement with AbbVie is expected to be recognized based on actual FTE effort and program progress until 2023 . • The $ 4.0 million of deferred revenue related to the second target under the Discovery Agreement with AbbVie is expected to be recognized ratably until 2024 . • The $ 19.6 million of deferred revenue related to the Amgen EGFR Products is expected to be recognized based on actual FTE effort and program progress until 2024 . • The $ 1.0 million of deferred revenue related to the Amgen Other Products is expected to be recognized ratably until 2023 . • The $ 43.7 million of deferred revenue related to the Astellas Agreement is expected to be recognized ratably until 2025 . • The $ 83.9 million of deferred revenue related to the BMS Agreement is expected to be recognized ratably until 2025 .

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2022
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	7. Stock-Based Compensation Stock Options Activities for the Company’s stock option plans for the six months ended June 30, 2022 were as follows: Options Outstanding Number of Weighted- Balances at December 31, 2021 12,192,216 $ 9.42 Options granted 3,416,918 3.55 Options exercised ( 100,990 ) 0.98 Option forfeited/expired ( 1,077,318 ) 8.93 Balances at June 30, 2022 14,430,826 $ 8.13 The Company recorded $ 2.8 million and $ 3.3 million of stock-based compensation expense related to the stock options for the three months ended June 30, 2022 and 2021, respectively. The Company recorded $ 5.7 million and $ 6.3 million of stock-based compensation expense related to the stock options for the six months ended June 30, 2022 and 2021, respectively. Time-based RSUs ("TRSU") Activities for the Company’s TRSUs for the six months ended June 30, 2022 were as follows: Number of Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2021 433,250 $ 5.34 RSU's awarded 655,410 3.89 RSU's vested — — RSU's cancelled ( 97,044 ) 4.75 Balance at June 30, 2022 991,616 $ 4.44 The Company recorded $ 0.4 million and $ 0.7 million of stock-based compensation expense related to the TRSUs for the three and six months ended June 30, 2022, respectively. The Company began granting TRSUs in the fourth quarter of 2021. Performance-based RSUs ("PSUs") In October 2021, the Company granted 435,000 PSUs as recognition awards to executive employees with an aggregated grant date fair value of $ 2.3 million. 50% of the PSUs granted will vest within one year of the grant date upon achievement of certain specific milestones ("Tranche 1") and the remaining 50% will vest within two years of the grant date upon achievement of additional company objectives ("Tranche 2"). The Company determined that it is not probable that the performance conditions will be satisfied for each of these Tranches and hence no compensation cost was recorded for these awards for the year ended December 31, 2021. As of June 30, 2022, the Company determined that the achievement of the milestones for Tranche 1 was probable and hence recorded $ 1.0 million of stock-based compensation expense for the three and six months ended June 30, 2022. As the achievement of the milestones for Tranche 2 was not considered probable, no compensation cost was recorded for these awards as of and for the three and six months ended June 30, 2022. Activities for the Company’s PSUs for the six months ended June 30, 2022 were as follows: Number of Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2021 435,000 $ 5.34 PSU's awarded — — PSU's vested — — PSU's cancelled ( 47,500 ) 5.34 Balance at June 30, 2022 387,500 $ 5.34 Stock-based Compensation Total stock-based compensation recorded related to options, TRSUs, PSUs and the ESPP was as follows: Three Months Ended Six Months Ended June 30, June 30, 2022 2021 2022 2021 (in thousands) Stock-based compensation expense: Research and development $ 2,091 $ 1,548 $ 3,696 $ 2,885 General and administrative 2,399 1,877 4,164 3,574 Total stock-based compensation expense $ 4,490 $ 3,425 $ 7,860 $ 6,459

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies Legal Proceedings On March 4, 2020 , Vytacera Bio, LLC filed a patent infringement lawsuit against the Company in the U.S. District Court for the District of Delaware. The lawsuit alleges that the Company's use, offers to sell, and/or sales of the Probody® technology platform for basic research applications constitutes infringement. The complaint seeks unspecified monetary damages. The Company filed an Answer, Affirmative Defenses, and Counterclaims on May 26, 2020 . Vytacera Bio, LLC filed its Answer to CytomX Therapeutics Inc.’s Counterclaims on June 5, 2020 . On October 13, 2021, the Court granted the parties’ stipulation to stay all pending case deadlines except for certain matters, pending resolution of claim construction. On May 9, 2022, the Court entered a claim construction ruling. Also on May 9, 2022, the case was assigned to the District of Delaware’s Vacant Judgeship. No new case deadlines have been set. The Company believes that the lawsuit is without merit and intends to vigorously defend itself, and has no t recorded any amount for claims associated with this lawsuit as of June 30, 2022.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2022
Income Tax Disclosure [Abstract]
Income Taxes	9. Income Taxes The Company maintains a full valuation allowance against its net deferred tax assets due to the Company’s history of losses as of June 30, 2022 and December 31, 2021 . The Company files income taxes in the U.S. federal jurisdiction, the state of California and various other U.S. states. The Company is currently under examination by the state of California for the years 2017 and 2018. The examination contests the Company’s tax position on revenue apportionment for upfront and milestone payments resulting from the Company’s collaboration and licensing agreements. As of the date of this filing, the state of California has not proposed adjustments to the tax returns. Due to the ongoing nature of the examination and discussions with the state of California, the Company is unable to estimate a date by which this matter will be resolved or reasonably estimate the potential impact should the tax position be revised. Based on the Company's current expectations and understanding of the reasonably possible outcomes, the Company does not anticipate that the resolution of this matter would result in a material impact on its financial position or results of operations.

Subsequent Event

Subsequent Event	6 Months Ended
	Jun. 30, 2022
Subsequent Events [Abstract]
Subsequent Event	10. Subsequent event Restructuring On July 6, 2022 the Company announced Phase 2 topline results for praluzatamab ravtansine in breast cancer and its decision to not advance this program ("praluzatamab ravtansine") alone given the data and financial market conditions. The Company will seek a collaboration partnership to further develop praluzatamab ravtansine in patients with advanced breast cancer. On July 13, 2022, the Company announced a restructuring plan to prioritize its resources on its emerging pre-clinical and early clinical pipeline as well as its existing collaboration partnerships. The restructuring plan will result in a reduction to its workforce by approximately 40 %, and is expected to be completed by the fourth quarter of 2022. The Company estimates that it will incur aggregate restructuring charges of approximately $ 10.0 million, primarily related to one-time severance payments and other employee-related costs, in the third and fourth quarters of 2022.

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying interim condensed financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (“SEC”) regarding interim financial reporting.
Unaudited Interim Financial Information	Unaudited Interim Financial Information The accompanying interim condensed financial statements and related disclosures are unaudited, have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for a fair statement of the results of operations for the periods presented. The condensed results of operations for the three and six months ended June 30, 2022 are not necessarily indicative of the results to be expected for the full year or for any other future year or interim period. The accompanying condensed financial statements should be read in conjunction with the audited financial statements and the related notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC.
Use of Estimates	Use of Estimates The preparation of the financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting periods. Actual results could differ from those estimates.
Cash, cash equivalents and restricted cash	Cash, cash equivalents and restricted cash The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed balance sheets that sum to the total of the amounts shown in the condensed statements of cash flows: June 30, 2022 December 31, 2021 June 30, 2021 December 31, 2020 (in thousands) Cash and cash equivalents $ 129,290 $ 205,530 $ 256,146 $ 191,859 Restricted cash - non-current assets 917 917 917 917 Total $ 130,207 $ 206,447 $ 257,063 $ 192,776 Restricted cash represents a standby letter of credit issued pursuant to an office lease.
Revenue Recognition	Revenue Recognition The Company’s revenues are primarily derived through its license, research, development and commercialization agreements. The terms of these types of agreements may include (i) licenses for the Company’s technology or programs, (ii) research and development services, and (iii) services or obligations in connection with participation in research or steering committees. Payments to the Company under these arrangements typically include one or more of the following: nonrefundable upfront and license fees, research funding, milestone and other contingent payments to the Company for the achievement of defined collaboration objectives and certain preclinical, clinical, regulatory and sales-based events, as well as royalties on sales of any commercialized products. The Company assesses whether the promises in its arrangements with customers are distinct performance obligations that should be accounted for separately. Judgment is required to determine whether the license to the Company’s intellectual property is distinct from the research and development services or participation on steering committees. The Company’s collaboration and license agreements may include contingent payments related to specified research, development and regulatory milestones. Such milestone payments are typically payable under the collaborations when the collaboration partner claims or selects a target, or initiates or advances a covered product candidate in preclinical or clinical development, upon submission for marketing approval of a covered product with regulatory authorities, or upon receipt of actual marketing approvals of a covered product or for additional indications. Milestone payments that are not within the control of the Company or the licensee, such as regulatory approvals, are not considered probable of being achieved until those approvals are received. At each reporting date, the Company re-evaluates whether the milestones are considered probable of being reached and estimates the amount to be included in the transaction price by using the most likely amount method. If it is probable that a significant revenue reversal would not occur, the associated milestone value is included in the transaction price in such period of determination. The Company’s collaboration and license agreements may also include contingent payments related to sales-based milestones. Sales-based milestones are typically payable when annual sales of a covered product reach specified levels. Sales-based milestones are recognized at the later of when the associated performance obligation has been satisfied or when the sales occur. Unlike other contingency payments, such as regulatory milestones, sales-based milestones are not included in the transaction price based on estimates at the inception of the contract; instead, they are included when the sales or usage occur. The transaction price in each arrangement is allocated to the identified performance obligations based on the relative standalone selling price (“SSP”) of each distinct performance obligation, which requires judgment. In instances where SSP is not directly observable, such as when a license or service is not sold separately, SSP is determined using information that may include market conditions and other observable inputs. Due to the early stage of the Company’s licensed technology, the license of such technology is typically combined with research and development services and steering committee participation as one performance obligation. In the event that the Company receives non-cash consideration such as consideration in the form of a research license and research support services from the counterparty, the transaction price of a non-monetary exchange that has commercial substance is estimated based on the fair value of the non-cash consideration received, which may be determined through a valuation analysis. In certain cases, the Company’s performance creates an asset that does not have an alternative use to the customer and the Company has an enforceable right to payment at all times for performance completed to date. In these cases, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. AbbVie Ireland Unlimited Company (“AbbVie”), one of the Company’s collaboration partners, entered into a license agreement with Seagen Inc., formerly Seattle Genetics, Inc. (“SGEN”) to license certain intellectual property rights. As part of the Company’s collaboration agreement with AbbVie, the Company is required to pay SGEN sublicense fees for certain milestone achievements and an annual maintenance fee. These sublicense fees are treated as reductions to the transaction price and combined with the performance obligation to which they relate.
Contract Balances	Contract Balances Customer payments are recorded as deferred revenue upon receipt or when due and may require deferral of revenue recognition to a future period until the Company satisfies its performance obligations under these arrangements. Amounts payable to the Company are recorded as accounts receivable when the Company’s right to consideration is unconditional.

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2022
Accounting Policies [Abstract]
Schedule of Cash, Cash Equivalents, and Restricted Cash	The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the condensed balance sheets that sum to the total of the amounts shown in the condensed statements of cash flows: June 30, 2022 December 31, 2021 June 30, 2021 December 31, 2020 (in thousands) Cash and cash equivalents $ 129,290 $ 205,530 $ 256,146 $ 191,859 Restricted cash - non-current assets 917 917 917 917 Total $ 130,207 $ 206,447 $ 257,063 $ 192,776

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jun. 30, 2022
Earnings Per Share [Abstract]
Summary of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share	The following weighted-average outstanding shares of potentially dilutive securities are excluded from the computation of diluted net loss per share for the periods presented, because including them would have been anti-dilutive: Three Months Ended Six Months Ended June 30, June 30, 2022 2021 2022 2021 Options, RSUs and ESPP to purchase common stock 15,226,820 12,117,149 14,888,352 11,837,707

Fair Value Measurements and I_2

Fair Value Measurements and Investments (Tables)	6 Months Ended
	Jun. 30, 2022
Fair Value Disclosures [Abstract]
Schedule of Investments Subject to Fair Value Measurements on a Recurring Basis	The following tables set forth the fair value of the Company’s investments subject to fair value measurements on a recurring basis and the level of inputs used in such measurements: June 30, 2022 Valuation Amortized Unrealized Unrealized Aggregate (in thousands) Assets Money market funds Level I $ 75,878 $ — $ — $ 75,878 Restricted cash (money market funds) Level I 917 — — 917 U.S. Government bonds Level I 100,037 — ( 1,162 ) 98,875 Total $ 176,832 $ — $ ( 1,162 ) $ 175,670 December 31, 2021 Valuation Amortized Unrealized Unrealized Aggregate (in thousands) Assets Money market funds Level I $ 165,736 $ — $ — $ 165,736 Restricted cash (money market funds) Level I 917 — — 917 U.S. Government bonds Level I 99,938 — ( 242 ) 99,696 Total $ 266,591 $ — $ ( 242 ) $ 266,349

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	6 Months Ended
	Jun. 30, 2022
Accrued Liabilities, Current [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following: June 30, December 31, 2022 2021 (in thousands) Research and clinical expenses $ 18,377 $ 18,861 Payroll and related expenses 7,109 9,576 Legal and professional expenses 2,259 1,468 Operating lease liabilities - short term 3,845 3,618 Other accrued expenses 142 713 Total $ 31,732 $ 34,236

Research and Collaboration Ag_2

Research and Collaboration Agreements (Tables)	6 Months Ended
	Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Revenue by Collaboration Partners	The following table summarizes the revenue by collaboration partner: Three Months Ended Six Months Ended June 30, June 30, 2022 2021 2022 2021 (in thousands) (in thousands) AbbVie $ 5,377 $ 2,078 $ 7,804 $ 3,306 Amgen 369 1,874 2,657 4,456 Astellas 5,014 4,931 10,031 9,687 Bristol Myers Squibb 7,405 7,405 14,810 14,810 Total revenue $ 18,165 $ 16,288 $ 35,302 $ 32,259
Summary of Contract Liabilities	The following table presents changes in the Company’s total contract liabilities during the six months ended June 30, 2022: Balance at Additions Deductions Balance at (in thousands) Contract liabilities: Deferred revenue $ 194,922 $ — $ ( 33,272 ) $ 161,650

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2022
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Schedule of Activities Under Company's Stock Option Plans	Activities for the Company’s stock option plans for the six months ended June 30, 2022 were as follows: Options Outstanding Number of Weighted- Balances at December 31, 2021 12,192,216 $ 9.42 Options granted 3,416,918 3.55 Options exercised ( 100,990 ) 0.98 Option forfeited/expired ( 1,077,318 ) 8.93 Balances at June 30, 2022 14,430,826 $ 8.13
Total Stock-based Compensation Recognized	Total stock-based compensation recorded related to options, TRSUs, PSUs and the ESPP was as follows: Three Months Ended Six Months Ended June 30, June 30, 2022 2021 2022 2021 (in thousands) Stock-based compensation expense: Research and development $ 2,091 $ 1,548 $ 3,696 $ 2,885 General and administrative 2,399 1,877 4,164 3,574 Total stock-based compensation expense $ 4,490 $ 3,425 $ 7,860 $ 6,459
Time based RSU
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Schedule of Company's TRSU Activities	Activities for the Company’s TRSUs for the six months ended June 30, 2022 were as follows: Number of Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2021 433,250 $ 5.34 RSU's awarded 655,410 3.89 RSU's vested — — RSU's cancelled ( 97,044 ) 4.75 Balance at June 30, 2022 991,616 $ 4.44
Performance based RSU
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Schedule of Activities for Company's PSUs	Activities for the Company’s PSUs for the six months ended June 30, 2022 were as follows: Number of Weighted Average Grant Date Fair Value Per Share Balance at December 31, 2021 435,000 $ 5.34 PSU's awarded — — PSU's vested — — PSU's cancelled ( 47,500 ) 5.34 Balance at June 30, 2022 387,500 $ 5.34

Basis of Presentation and Sum_4

Basis of Presentation and Summary of Significant Accounting Policies - Summary of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021		Jun. 30, 2021	Dec. 31, 2020
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 129,290	$ 205,530	[1]	$ 256,146	$ 191,859
Restricted cash - non-current assets	917	917	[1]	917	917
Total	$ 130,207	$ 206,447		$ 257,063	$ 192,776
[1] The condensed balance sheet as of December 31, 2021 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2021.

Net Loss Per Share - Summary of

Net Loss Per Share - Summary of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Options, RSUs and ESPP to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	15,226,820	12,117,149	14,888,352	11,837,707

Fair Value Measurements and I_3

Fair Value Measurements and Investments - Schedule of Investments Subject to Fair Value Measurements on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021		Jun. 30, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 129,290	$ 205,530	[1]	$ 256,146	$ 191,859
Aggregate Fair Value	175,670	266,349
Gross Unrealized Holding Losses	(1,162)	(242)
Amortized Cost	176,832	266,591
Level I | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash and cash equivalents	75,878	165,736
Level I | Restricted cash (money market funds)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Restricted cash	917	917
Level I | U.S. Government bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Investments, Amortized Cost	100,037	99,938
Investments, Gross Unrealized Losses	(1,162)	(242)
Investments, Aggregate Fair Value	$ 98,875	$ 99,696
[1] The condensed balance sheet as of December 31, 2021 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2021.

Fair Value Measurements and I_4

Fair Value Measurements and Investments - Additional Information (Details)	6 Months Ended
	Jun. 30, 2022
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities, available for sale, maturity period	12 months

Accrued Liabilities - Summary o

Accrued Liabilities - Summary of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Accrued Liabilities, Current [Abstract]
Research and clinical expenses	$ 18,377	$ 18,861
Payroll and related expenses	7,109	9,576
Legal and professional expenses	2,259	1,468
Operating lease liabilities - short term	3,845	3,618
Other accrued expenses	142	713
Total	$ 31,732	$ 34,236	[1]
[1] The condensed balance sheet as of December 31, 2021 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2021.

Research and Collaboration Ag_3

Research and Collaboration Agreements - Schedule of Revenue by Collaboration Partners (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	$ 18,165	$ 16,288	$ 35,302	$ 32,259
AbbVie
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	5,377	2,078	7,804	3,306
Amgen
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	369	1,874	2,657	4,456
Astellas
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	5,014	4,931	10,031	9,687
Bristol Myers Squibb
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue	$ 7,405	$ 7,405	$ 14,810	$ 14,810

Research and Collaboration Ag_4

Research and Collaboration Agreements - AbbVie Ireland Unlimited Company - Additional Information (Details) $ in Thousands	1 Months Ended		3 Months Ended				6 Months Ended
	Jun. 30, 2019 USD ($)	Apr. 30, 2016 USD ($) Agreement Target	Jun. 30, 2022 USD ($)	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022 USD ($)	Jun. 30, 2021	Dec. 31, 2021 USD ($)	Mar. 31, 2017 Target
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Type of Revenue [Extensible List]			us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Deferred revenue			$ 161,650				$ 161,650		$ 194,922
Collaborative Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of collaboration agreements | Agreement		2
AbbVie Ireland Unlimited Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payment received							100,000
AbbVie Ireland Unlimited Company | Collaborative Arrangement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Percentage of net profits or net losses related to development and commercialization costs		35%
AbbVie Ireland Unlimited Company | CD71 Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received		$ 20,000
Deferred revenue			9,500				9,500		16,100
AbbVie Ireland Unlimited Company | CD71 Agreement | U.S
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Profit split on U.S. sales		35%
AbbVie Ireland Unlimited Company | CD71 Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent payments receivable upon achieving development, regulatory and commercial milestones		$ 470,000
AbbVie Ireland Unlimited Company | Discovery Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received		$ 10,000
Number of targets selected | Target										1
Deferred revenue			$ 4,000				$ 4,000		$ 5,200
AbbVie Ireland Unlimited Company | Discovery Agreement | Second Target
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone payments received	$ 10,000
AbbVie Ireland Unlimited Company | Discovery Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets | Target		2
AbbVie Ireland Unlimited Company | Discovery Agreement | Maximum | Development, Regulatory and Commercial Milestone Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable		$ 265,000

Research and Collaboration Ag_5

Research and Collaboration Agreements - Amgen, Inc - Additional Information (Details) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended				6 Months Ended
	Sep. 29, 2017 USD ($) Target	Oct. 31, 2017 USD ($) $ / shares shares	Jun. 30, 2022 USD ($)	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Common stock, value of shares issued in connection with agreement							$ 0	$ 107,712
Type of Revenue [Extensible List]			us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Deferred revenue			$ 161,650				$ 161,650		$ 194,922
Amgen Inc | Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payment received		$ 40,000
Common stock, shares issuable under agreement | shares		1,156,069
Common stock, shares issuable under agreement, price per share | $ / shares		$ 17.30
Common stock, value of shares issued in connection with agreement		$ 20,000
Number of targets selected | Target	1
Number of additional collaboration target | Target	2
Amgen Inc | Maximum | Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent payments payable	$ 203,000
Amgen Inc | EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			19,600				19,600
Amgen Inc | EGFR Products | Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			19,600				19,600		21,800
Amgen Inc | EGFR Products | Maximum | Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable	$ 460,000
Percentage share of profit and losses	50%
Amgen Inc | Amgen Products | Maximum | Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable	$ 950,000
Number of targets | Target	3
Amgen Inc | Amgen Other Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			1,000				1,000
Amgen Inc | Amgen Other Products | Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			$ 1,000				$ 1,000		$ 1,400

Research and Collaboration Ag_6

Research and Collaboration Agreements - Astellas Pharma Inc - Additional Information (Details) $ in Thousands		1 Months Ended
	Mar. 23, 2020 USD ($) Target	Oct. 31, 2017 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 29, 2017 USD ($) Target
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			$ 161,650	$ 194,922
Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			43,700
Amgen Inc | EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			19,600
Collaboration and License Agreement | Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets selected | Target	1
Number of additional collaboration target | Target	3
Upfront payment received	$ 80,000
Deferred revenue			43,700	51,600
Amount due from agreement			1,000	800
Collaboration and License Agreement | Astellas Pharma Inc. | Additional Contingent Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable	$ 900,000
Collaboration and License Agreement | Astellas Pharma Inc. | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets | Target	4
Right to expand the number of additional collaboration target | Target	5
Contingent milestone payments receivable	$ 1,600,000
Collaboration and License Agreement | Astellas Pharma Inc. | Minimum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Right to expand the number of additional collaboration target | Target	3
Collaboration and License Agreement | Amgen Inc
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of targets selected | Target					1
Number of additional collaboration target | Target					2
Upfront payment received		$ 40,000
Collaboration and License Agreement | Amgen Inc | EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			$ 19,600	$ 21,800
Collaboration and License Agreement | Amgen Inc | Maximum | EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable					$ 460,000

Research and Collaboration Ag_7

Research and Collaboration Agreements - Bristol-Myers Squibb Company - Additional Information (Details) $ in Thousands			3 Months Ended				6 Months Ended
	Apr. 25, 2017 USD ($) Target	Jul. 07, 2014 USD ($) Target Term	Jun. 30, 2022 USD ($)	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022 USD ($)	Jun. 30, 2021	Dec. 31, 2021 USD ($)	Feb. 28, 2021 USD ($)	Mar. 17, 2017 Target
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Type of Revenue [Extensible List]			us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember	us-gaap:LicenseAndServiceMember
Deferred revenue			$ 161,650				$ 161,650		$ 194,922
Bristol Myers Squibb Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue			83,900				$ 83,900
Collaborative Arrangement | Bristol Myers Squibb Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration target research term		2 years
Number of additional collaboration target | Target		2
Research terms							Each collaboration target had a two-year research term and the two additional targets had to be nominated by Bristol Myers Squibb within five years of the effective date of the BMS Agreement. The research term for each collaboration target could be extended in one year increments up to three times.
Extension of research term for each collaboration target		1 year
Upfront payment received	$ 200,000	$ 50,000
Contingent milestone payments receivable										$ 1,779,000
Number of research targets selected | Target	8
Total transaction price		272,800
Upfront payment received		250,000
Research and development service fees		10,800
Milestone payment received		$ 12,000
Estimated research service termination date		Apr. 25, 2025
Deferred revenue			$ 83,900				$ 83,900		$ 98,800
Collaborative Arrangement | Maximum | Bristol Myers Squibb Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of oncology target | Target		4
Number of collaboration target | Target		2
Period of nomination of additional target from effective date		5 years
Times of increments for extended collaboration target research time | Term		3
Contingent milestone payments receivable	$ 3,586,000	$ 1,192,000
Collaborative Arrangement | Maximum | Bristol Myers Squibb Company | Each Of Two Additional Targets
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent milestone payments receivable		$ 25,000
Collaboration and License Agreement | Maximum | Bristol Myers Squibb Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of additional collaboration target | Target											8

Research and Collaboration Ag_8

Research and Collaboration Agreements - Summary of Contract Liabilities (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2022 USD ($)
Revenue from Contract with Customer [Abstract]
Balance at Beginning of Period	$ 194,922
Additions	0
Deductions	(33,272)
Balance at End of Period	$ 161,650

Research and Collaboration Ag_9

Research and Collaboration Agreements - Contract Liabilities - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 161,650	$ 194,922
AbbVie Ireland Unlimited Company | CD71 Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 9,500	$ 16,100
Deferred Revenue Recognition Maturity Year	2023
AbbVie Ireland Unlimited Company | Second Target under Discovery Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 4,000
Deferred Revenue Recognition Maturity Year	2024
Amgen | EGFR Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 19,600
Deferred Revenue Recognition Maturity Year	2024
Amgen | Amgen Other Products
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 1,000
Deferred Revenue Recognition Maturity Year	2023
Bristol Myers Squibb Company
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 83,900
Deferred Revenue Recognition Maturity Year	2025
Astellas Pharma Inc.
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Deferred revenue	$ 43,700
Deferred Revenue Recognition Maturity Year	2025

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Activities Under Company's Stock Option Plans (Details)	6 Months Ended
	Jun. 30, 2022 $ / shares shares
Number of Options
Balance,beginning of the period | shares	12,192,216
Options granted | shares	3,416,918
Options exercised | shares	(100,990)
Option forfeited/expired | shares	(1,077,318)
Balance, end of the period | shares	14,430,826
Options Outstanding, Weighted-Average Exercise Price Per Share
Balances, beginning of the period | $ / shares	$ 9.42
Options granted | $ / shares	3.55
Options exercised | $ / shares	0.98
Option forfeited/expired | $ / shares	8.93
Balances, end of the period | $ / shares	$ 8.13

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Company's TRSU Activities (Details) - Time based RSU	6 Months Ended
	Jun. 30, 2022 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Balance at December 31, 2021 | shares	433,250
Units Awarded | shares	655,410
Units vested | shares	0
Units cancelled | shares	(97,044)
Balance at June 30, 2022 | shares	991,616
Weighted Average Grant Date Fair Value, Beginning Balance | $ / shares	$ 5.34
Units Awarded | $ / shares	3.89
Units vested | $ / shares	0
Units cancelled | $ / shares	4.75
Weighted Average Grant Date Fair Value, Ending Balance | $ / shares	$ 4.44

Stock-Based Compensation - Sc_3

Stock-Based Compensation - Schedule of Activities for Company's PSUs (Details) - Performance based RSU - $ / shares	1 Months Ended	6 Months Ended
	Oct. 31, 2021	Jun. 30, 2022
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Balance at December 31, 2021		435,000
Units Awarded	435,000	0
Units vested		0
Units cancelled		(47,500)
Balance at June 30, 2022		387,500
Weighted Average Grant Date Fair Value, Beginning Balance		$ 5.34
Units Awarded		0
Units vested		0
Units cancelled		5.34
Weighted Average Grant Date Fair Value, Ending Balance		$ 5.34

Stock-Based Compensation - Tota

Stock-Based Compensation - Total Stock-based Compensation Recognized (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 4,490	$ 3,425	$ 7,860	$ 6,459
Research and development
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	2,091	1,548	3,696	2,885
General and administrative
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 2,399	$ 1,877	$ 4,164	$ 3,574

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		6 Months Ended
	Oct. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 4,490	$ 3,425	$ 7,860	$ 6,459
Time based RSU
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		400		$ 700
Granted				655,410
Performance based RSU
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Granted	435,000			0
RSU's Awarded, Grant date fair value	$ 2,300
Vesting rights, description				50% of the PSUs granted will vest within one year of the grant date upon achievement of certain specific milestones ("Tranche 1") and the remaining 50% will vest within two years of the grant date upon achievement of additional company objectives ("Tranche 2").
Performance based RSU | Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		1,000		$ 1,000
Performance based RSU | Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		0		0
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 2,800	$ 3,300	$ 5,700	$ 6,300

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) - USD ($) $ in Thousands		6 Months Ended
	Mar. 04, 2020	Jun. 30, 2022
Loss Contingencies [Line Items]
Loss contingency, answer, affirmative defenses and counterclaims filing date	May 26, 2020
Loss contingency, answer and counterclaims by plaintiff filing date	Jun. 05, 2020
Patent Infringement Lawsuit
Loss Contingencies [Line Items]
Lawsuit filed date	March 4, 2020
Name of plaintiff		Vytacera Bio, LLC
Loss contingency claim amount		$ 0

Subsequent Event - Additional I

Subsequent Event - Additional Information (Details) - Subsequent Event $ in Millions	Jul. 06, 2022 USD ($)
Subsequent Event [Line Items]
Restructuring Charges	$ 10
Percentage of Workforce Reduction	40%