Chinook Therapeutics (KDNY) 10-Q 12 May 22 2022 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2022	May 06, 2022
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2022
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Document Quarterly Report	true
Document Transition Report	false
Trading Symbol	KDNY
Security Exchange Name	NASDAQ
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Entity Interactive Data Current	Yes
Entity Registrant Name	CHINOOK THERAPEUTICS, INC.
Entity Central Index Key	0001435049
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Shell Company	false
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		55,177,252
Entity Current Reporting Status	Yes
Entity File Number	001-37345
Entity Tax Identification Number	94-3348934
Entity Incorporation, State or Country Code	DE
Entity Address, Address Line One	400 Fairview Avenue North, Suite 900
Entity Address, City or Town	Seattle
Entity Address, State or Province	WA
Entity Address Postal Zip Code	98109
City Area Code	(206)
Local Phone Number	485-7241

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 103,500	$ 181,724
Marketable securities	172,599	105,113
Accounts receivable	2,947	10,061
Prepaid expenses and other current assets	6,727	3,741
Total current assets	285,773	300,639
Marketable securities	53,933	68,215
Property and equipment, net	18,263	18,935
Restricted cash	2,074	2,074
Operating lease right-of-use assets	53,922	55,385
Investment in equity securities	41,200	41,200
Equity method investment	7,201	8,205
Intangible assets, net	25,580	26,009
In-process research & development	36,550	36,550
Goodwill	117	117
Other assets	6,657	6,474
Total assets	531,270	563,803
Current liabilities:
Accounts payable	9,039	8,580
Accrued and other current liabilities	12,946	17,104
Operating lease liabilities	4,581	4,401
Contingent value rights liability	10,000	10,000
Total current liabilities	36,566	40,085
Contingent value rights liability - non-current	23,963	24,591
Contingent consideration liability	4,750	5,160
Deferred tax liabilities	735	735
Operating lease liabilities, net of current maturities	38,461	39,589
Total liabilities	104,475	110,160
Commitments and contingencies (Note 12)
Stockholders’ equity:
Preferred stock, $0.0001 par value; 10,000 shares authorized as of March 31, 2022 and December 31, 2021; no shares issued and outstanding at March 31, 2022 and December 31, 2021
Common stock, $0.0001 par value; 300,000 shares authorized as of March 31, 2022 and December 31, 2021; 55,117 and 54,761 shares issued and outstanding at March 31, 2022 and December 31, 2021	6	5
Additional paid-in capital	691,776	685,459
Accumulated deficit	(263,450)	(231,766)
Accumulated other comprehensive loss	(1,537)	(55)
Total stockholders’ equity	426,795	453,643
Total liabilities and stockholders’ equity	$ 531,270	$ 563,803

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2022	Dec. 31, 2021
Statement Of Financial Position [Abstract]
Preferred stock par value per share	$ 0.0001	$ 0.0001
Preferred stock shares authorized	10,000,000	10,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0
Common stock par value per share	$ 0.0001	$ 0.0001
Common stock shares authorized	300,000,000	300,000,000
Common stock shares issued	55,117,000	54,761,000
Common stock shares outstanding	55,117,000	54,761,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement Of Income And Comprehensive Income [Abstract]
Collaboration and license revenue	$ 2,697	$ 351
Operating expenses:
Research and development	26,252	25,697
General and administrative	7,868	9,543
Change in fair value of contingent consideration and contingent value rights liabilities	(1,038)	1,839
Amortization of intangible assets	429	420
Total operating expenses	33,511	37,499
Loss from operations	(30,814)	(37,148)
Other expense, net	(95)	(67)
Loss before income taxes and share of net loss of equity method investment	(30,909)	(37,215)
Share of net loss of equity method investment	(775)
Net loss	$ (31,684)	$ (37,215)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.54)	$ (0.88)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted	58,340	42,136
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax of $0	$ 107	$ 38
Unrealized gain (loss) on marketable debt securities, net of tax of $0	(1,589)	16
Total other comprehensive income (loss)	(1,482)	54
Comprehensive loss	$ (33,166)	$ (37,161)

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Statement Of Income And Comprehensive Income [Abstract]
Foreign currency translation adjustments, tax	$ 0	$ 0
Unrealized gain (loss) on marketable debt securities, tax	$ 0	$ 0

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2020	$ 334,622	$ 4	$ 463,436	$ (128,829)	$ 11
Beginning balance, Shares at Dec. 31, 2020		42,282
Issuance of common stock upon exercise of stock options and warrants	580		580
Issuance of common stock upon exercise of stock options and warrants, shares		100
Stock-based compensation expense	2,478		2,478
Other comprehensive loss	54				54
Net loss	(37,215)			(37,215)
Ending balance at Mar. 31, 2021	300,519	$ 4	466,494	(166,044)	65
Ending balance, Shares at Mar. 31, 2021		42,382
Beginning balance at Dec. 31, 2021	$ 453,643	$ 5	685,459	(231,766)	(55)
Beginning balance, Shares at Dec. 31, 2021	54,761	54,761
Issuance of common stock upon exercise of stock options and vesting of restricted stock units	$ 2,049	$ 1	2,048
Issuance of common stock upon exercise of stock options and vesting of restricted stock units, shares		356
Stock-based compensation expense	4,269		4,269
Other comprehensive loss	(1,482)				(1,482)
Net loss	(31,684)			(31,684)
Ending balance at Mar. 31, 2022	$ 426,795	$ 6	$ 691,776	$ (263,450)	$ (1,537)
Ending balance, Shares at Mar. 31, 2022	55,117	55,117

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash Flows from Operating Activities
Net loss	$ (31,684)	$ (37,215)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	866	804
Loss on disposal of property and equipment	234
Amortization of intangible assets	429	420
Non-cash operating lease expense	1,528	1,291
Stock-based compensation expense	4,269	2,478
Change in fair value of contingent consideration and contingent value rights liabilities	(1,038)	1,839
Accretion of discounts and amortization of premiums on marketable securities	406
Share of net loss of equity method investment	775
Changes in operating assets and liabilities:
Accounts receivable	7,114	6
Prepaid expenses and other assets	(3,155)	(9)
Accounts payable	745	3,814
Accrued and other liabilities	(4,191)	(720)
Operating lease liabilities	(1,020)	(694)
Deferred revenue		(95)
Net cash used in operating activities	(24,722)	(28,081)
Cash Flows from Investing Activities
Purchases of marketable securities	(79,033)	(33,657)
Proceeds from marketable securities	23,834	41,818
Purchases of property and equipment	(374)	(594)
Proceeds from sale of property and equipment		267
Net cash provided by (used in) investing activities	(55,573)	7,834
Cash Flows from Financing Activities
Proceeds from exercise of stock options and warrants	2,049	580
Previously incurred issuance costs related to an underwritten public offering paid during period	(286)
Net cash provided by financing activities	1,763	580
Effect of exchange rate changes on cash, cash equivalents and restricted cash	308	9
Net decrease in cash, cash equivalents and restricted cash	(78,224)	(19,658)
Cash, cash equivalents and restricted cash at beginning of period	183,798	189,500
Cash, cash equivalents and restricted cash at end of period	105,574	169,842
Reconciliation of Cash, Cash Equivalents and Restricted Cash
Cash and cash equivalents	103,500	168,092
Restricted cash	2,074	1,750
Total cash, cash equivalents and restricted cash	105,574	169,842
Supplemental Cash Flow Information
Cash paid for amounts included in the measurement of lease liabilities	1,861	1,423
Supplemental Disclosure of Non-Cash Investing and Financing Activities
Purchases of property and equipment included in accounts payable and in accrued and other current liabilities	157	$ 76
Receivable from option exercises	$ 1,325

Description of Business

Description of Business	3 Months Ended
	Mar. 31, 2022
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business	1. Description of Business Chinook Therapeutics, Inc. (the “Company”, “Chinook”, “we”, “our”, or “us”) is a clinical-stage biopharmaceutical company focused on discovering, developing and commercializing precision medicines for kidney diseases. On October 5, 2020, Aduro Biotech, Inc. (“Aduro”) completed its merger with Chinook Therapeutics U.S., Inc. (“Private Chinook”), pursuant to the terms of a merger agreement dated as of June 1, 2020, and amended on August 17, 2020, by which a wholly owned subsidiary Our lead clinical program is atrasentan, an endothelin receptor antagonist that was in-licensed from AbbVie in late 2019. In March 2021, we initiated the phase 3 ALIGN trial of atrasentan for IgA nephropathy (“IgAN”) and in April 2021, we initiated the phase 2 AFFINITY basket trial of atrasentan for proteinuric glomerular diseases. Our second product candidate, BION-1301, is an anti-APRIL monoclonal antibody also in phase 1/2 development for patients with IgAN. Our third product candidate is CHK-336, an oral small molecule LDHA inhibitor for the treatment of primary and secondary hyperoxaluria and idiopathic kidney stone formation. In April 2022, we initiated a phase 1 clinical trial of CHK-336 in healthy volunteers. In addition, we are building our precision medicine pipeline through research and discovery programs for other rare, severe chronic kidney diseases. We were incorporated in Delaware and are headquartered in Seattle, Washington.

Basis of Presentation and Conso

Basis of Presentation and Consolidation, Use of Estimates and Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation and Consolidation, Use of Estimates and Recent Accounting Pronouncements	2. Basis of Presentation and Consolidation, Use of Estimates and Recent Accounting Pronouncements Basis of Presentation and Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. GAAP have been condensed or omitted, and accordingly the unaudited condensed consolidated financial statements do not include all of the information and notes required by U.S. GAAP for complete financial statements. These financial statements have been prepared on the same basis as our annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair presentation of financial information. The results of operations for the three months ended March 31, 2022 are not necessarily indicative of the results to be expected for the year ending December 31, 2022 or for any other interim period or for any other future year. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2021 included in our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on March 17, 2022. The condensed consolidated financial statements include the accounts of Chinook Therapeutics, Inc. and our wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of expenses during the reporting periods. Such estimates include the valuation of intangible assets, acquired property and equipment, investments, contingent value rights (“CVR”) liability, contingent consideration liability, lease right-of-use assets, and lease obligations, as well as Risks and Uncertainties We are subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, reliance on single-source vendors and collaborators, availability of raw materials, patentability of our products and processes and clinical efficacy and safety of our products under development, compliance with government regulations and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical studies, clinical trials and regulatory approval, prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting. Our product candidates are still in development and, to date, none of our product candidates have been approved for sale and, therefore, we have not generated any revenue from product sales. There can be no assurance that our research and development will be successfully completed, that adequate protection for our intellectual property will be obtained or maintained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if our product development efforts are successful, it is uncertain when, if ever, we will generate revenue from product sales. We operate in an environment of rapid technological change and substantial competition from other pharmaceutical and biotechnology companies. In addition, we are dependent upon the services of our employees, consultants and other third parties. Moreover, the current COVID-19 pandemic, which is impacting worldwide economic activity, poses risk that we or our employees, contractors, suppliers, and other partners may be prevented from conducting business activities for an indefinite period of time which may delay the start-up and conduct of our clinical trials, and negatively impact manufacturing and testing activities performed by third parties. Any significant delays may Recent Accounting Pronouncements Recent Accounting Pronouncements, Not Yet Adopted In June 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standard Update (“ASU”) No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments Recently Adopted Accounting Pronouncements In May 2021, the FASB issued ASU No. 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815- 40)

Reverse Merger and Contingent V

Reverse Merger and Contingent Value Rights	3 Months Ended
	Mar. 31, 2022
Business Combinations [Abstract]
Reverse Merger and Contingent Value Rights	3. Reverse Merger and Contingent Value Rights We completed our Merger with Aduro on October 5, 2020. At the effective time of the Merger, we also entered into an agreement pursuant to which Aduro’s common stockholders of record as of the close of business on October 2, 2020 received one CVR for each outstanding share of Aduro common stock held by such stockholder on such date (the “CVR Agreement”). Each CVR represents the contractual right to receive payments from us upon the receipt of consideration resulting from milestones and royalties from certain pre-existing agreements and the disposition or licensing of any of Aduro’s non-renal assets, net of deductions permitted under the CVR Agreement, including taxes and certain other expenses.

Cash, Cash Equivalents and Mark

Cash, Cash Equivalents and Marketable Securities	3 Months Ended
	Mar. 31, 2022
Cash And Cash Equivalents [Abstract]
Cash, Cash Equivalents and Marketable Securities	4. Cash, Cash Equivalents and Marketable Securities Cash, cash equivalents and marketable securities consisted of the following (in thousands): March 31, 2022 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash and cash equivalents: Cash $ 42,703 $ — $ — $ 42,703 Money market funds 25,506 — — 25,506 Commercial paper 30,287 — (2 ) 30,285 U.S. government and agency securities 5,006 — — 5,006 Total cash and cash equivalents $ 103,502 $ — $ (2 ) $ 103,500 Marketable securities: Commercial paper $ 33,550 $ 1 $ (27 ) $ 33,524 U.S. government and agency securities 128,214 1 (1,001 ) 127,214 Corporate debt securities 66,487 — (693 ) 65,794 Total marketable securities $ 228,251 $ 2 $ (1,721 ) $ 226,532 December 31, 2021 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash and cash equivalents: Cash $ 44,499 $ — $ — $ 44,499 Money market funds 117,023 — — 117,023 Commercial paper 16,898 — (1 ) 16,897 Corporate debt securities 3,306 — (1 ) 3,305 Total cash and cash equivalents $ 181,726 $ — $ (2 ) $ 181,724 Marketable securities: Commercial paper $ 34,978 $ — $ (10 ) $ 34,968 U.S. government and agency securities 85,309 1 (88 ) 85,222 Corporate debt securities 53,172 4 (38 ) 53,138 Total marketable securities $ 173,459 $ 5 $ (136 ) $ 173,328 The amortized cost and estimated fair value of our available-for-sale marketable securities by contractual maturity are summarized below as of March 31, 2022 (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Mature in one year or less $ 173,306 $ 2 $ (709 ) $ 172,599 Mature after one year through two years 54,945 — (1,012 ) 53,933 Total available-for-sale marketable securities $ 228,251 $ 2 $ (1,721 ) $ 226,532 None of our marketable securities were in a continuous unrealized loss position as of March 31, 2022. We review individual securities in our portfolio to determine whether a decline in a security’s fair value below the amortized cost basis is other-than-temporary. We determined that as of March 31, 2022, there were no investments in our portfolio that were other-than-temporarily impaired.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	5. Fair Value Measurements We record certain financial assets and liabilities at fair value in accordance with the provisions of Accounting Standards Codification (“ASC”) Topic 820 on fair value measurements. As defined in the guidance, fair value, defined as an exit price, represents the amount that would be received to sell an asset or pay to transfer a liability in an orderly transaction between market participants. As a result, fair value is a market-based approach that should be determined based on assumptions that market participants would use in pricing an asset or a liability. As a basis for considering these assumptions, the guidance defines a three-tier valuation hierarchy that prioritizes the inputs used in the valuation methodologies in measuring fair value. Level 1: Unadjusted quoted prices in active, accessible markets for identical assets or liabilities. Level 2: Quoted prices in markets that are not active or financial instruments for which all significant Level 3: Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable activity. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The determination of a financial instrument’s level within the fair value hierarchy is based on an assessment of the lowest level of any input that is significant to the fair value measurement. We consider observable data to be market data which is readily available, regularly distributed or updated, reliable and verifiable, not proprietary, and provided by independent sources that are actively involved in the relevant market. The following tables present information about our financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): March 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash and cash equivalents: Cash and money market funds $ 68,209 $ — $ — $ 68,209 Commercial paper — 30,285 — 30,285 U.S. government and agency securities — 5,006 5,006 Total cash and cash equivalents 68,209 35,291 — 103,500 Marketable securities: Commercial paper — 33,524 — 33,524 U.S. government and agency securities — 127,214 — 127,214 Corporate debt securities — 65,794 — 65,794 Total marketable securities — 226,532 — 226,532 Total fair value of assets $ 68,209 $ 261,823 $ — $ 330,032 Liabilities: Contingent value rights liability $ — $ — $ 33,963 $ 33,963 Contingent consideration liability — — 4,750 4,750 Total fair value of liabilities $ — $ — $ 38,713 $ 38,713 December 31, 2021 Level 1 Level 2 Level 3 Total Assets: Cash and cash equivalents: Cash and money market funds $ 161,522 $ — $ — $ 161,522 Commercial paper — 16,897 — 16,897 Corporate debt securities — 3,305 — 3,305 Total cash and cash equivalents 161,522 20,202 — 181,724 Marketable securities: Commercial paper — 34,968 — 34,968 U.S. government and agency securities — 85,222 — 85,222 Corporate debt securities — 53,138 — 53,138 Total marketable securities — 173,328 — 173,328 Total fair value of assets $ 161,522 $ 193,530 $ — $ 355,052 Liabilities: Contingent value rights liability $ — $ — $ 34,591 $ 34,591 Contingent consideration liability — — 5,160 5,160 Total fair value of liabilities $ — $ — $ 39,751 $ 39,751 Money market funds are included within Level 1 of the fair value hierarchy because they are valued using quoted market prices. Other cash equivalents and marketable securities, such as commercial paper, U.S. government and agency securities, and corporate debt securities are classified within Level 2 of the fair value hierarchy as the valuation is obtained from third-party pricing services, which utilize industry standard valuation models, including both income-based and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate the fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities, estimated interest rates based on the issuer credit rating and term, and other observable inputs. The following table presents a summary of the changes in the fair value of our Level 3 financial instruments (in thousands): Contingent Value Rights Liability Contingent Consideration Liability Balance at December 31, 2021 $ 34,591 $ 5,160 Net change in fair value upon remeasurement (628 ) (410 ) Balance at March 31, 2022 $ 33,963 $ 4,750 The fair values of the CVR and contingent consideration liabilities are based on significant unobservable inputs, which represent Level 3 measurements within the fair value hierarchy. In determining the fair value of the CVR and the contingent consideration liabilities, we used the income approach, primarily discounted cash flow models. The discounted cash flow models require the use of significant judgment, estimates and assumptions, including estimated revenues and costs, the probability of technical and regulatory success, and discount rates. For the three months ended March 31, 2022 and 2021, the aggregate change in fair value of the CVR and the contingent consideration liabilities was a decrease of $1.0 million and an increase $1.8 million, respectively, and was recorded in the consolidated statement of operations and comprehensive loss. The change in the fair value during the periods resulted from a change in estimate of the potential future proceeds derived from Aduro’s license agreement with Merck.

Property and Equipment, Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2022
Property Plant And Equipment [Abstract]
Property and Equipment, Net	6. Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): March 31, December 31, 2022 2021 Research and lab equipment $ 3,493 $ 3,366 Computer equipment and software 1,266 1,497 Furniture and fixtures 1,349 1,224 Leasehold improvements 16,982 16,976 Total property and equipment 23,090 23,063 Total accumulated depreciation (4,827 ) (4,128 ) Property and equipment, net $ 18,263 $ 18,935 Depreciation and amortization expense for property and equipment for the three months ended March 31, 2022 and 2021 was $0.9 million and $0.7 million, respectively. Approximately $2.9 million of our property and equipment as of March 31, 2022 is located in Canada.

Goodwill and Intangible Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2022
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	7. Goodwill and Intangible Assets Goodwill The gross carrying amount and net book value of goodwill was $0.1 million at March 31, 2022, all of which resulted from the Merger. We test Intangible assets The gross carrying amounts and net book value of intangible assets were as follows (in thousands): March 31, 2022 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: Acquired license agreement $ 26,685 $ 2,360 $ 24,325 In-place lease 1,433 178 1,255 Total intangible assets with finite lives 28,118 2,538 25,580 Acquired in-process research & development ("IPR&D") assets 36,550 — 36,550 Total intangible and acquired IPR&D assets $ 64,668 $ 2,538 $ 62,130 December 31, 2021 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: Acquired license agreement $ 26,685 $ 1,968 $ 24,717 In-place lease 1,433 141 1,292 Total intangible assets with finite lives 28,118 2,109 26,009 Acquired IPR&D assets 36,550 — 36,550 Total intangible and acquired IPR&D assets $ 64,668 $ 2,109 $ 62,559 Intangible assets are carried at cost less accumulated amortization and impairment. Amortization is over periods of 9 to 17 years, with an original weighted average period of 16.7 years, and the amortization expense is recorded in operating expenses. We test our acquired IPR&D assets for impairment on an annual basis, or more frequently if an impairment indicator exists. Amortization expense was $0.4 million and $0.4 million for the three months ended March 31, 2022 and 2021, respectively. Based on finite-lived intangible assets recorded as of March 31, 2022, the estimated future amortization expense for the next five years is as follows (in thousands): Year Ending December 31, Estimated Amortization Expense 2022 (remaining nine months) $ 1,293 2023 1,733 2024 1,733 2025 1,733 2026 1,733 Thereafter 17,355

Accrued and Other Current Liabi

Accrued and Other Current Liabilities	3 Months Ended
	Mar. 31, 2022
Accrued Liabilities And Other Liabilities [Abstract]
Accrued and Other Current Liabilities	8. Accrued and other current liabilities consisted of the following (in thousands): March 31 December 31, 2022 2021 Research and development costs $ 7,703 $ 8,397 Compensation and benefits 3,478 6,455 Sublease rent and security deposit 1,072 1,067 Business taxes and licensing fees 455 421 Consulting and outside services 208 424 Other 30 340 Total accrued and other current liabilities $ 12,946 $ 17,104

Investment in Equity Securities

Investment in Equity Securities	3 Months Ended
	Mar. 31, 2022
Investments Debt And Equity Securities [Abstract]
Investment in Equity Securities	9. Investment in Equity Securities In November 2021, we entered into agreements related to the formation of SanReno, a corporation established to develop, manufacture and commercialize kidney disease therapies in mainland China, Hong Kong, Macau, Taiwan and Singapore (collectively, the “Territory”). In connection with the formation of SanReno and pursuant to a license agreement entered into between Chinook and SanReno in November 2021 (the “China License Agreement”), Chinook granted SanReno exclusive licenses under certain intellectual property to develop and commercialize atrasentan and BION-1301 in the Territory for use in all human indications. In return, Chinook received 40.0 million Series A preferred shares in SanReno representing 50% ownership of the outstanding voting securities and a warrant to purchase a total of 5.0 million common shares of SanReno at an exercise price of $0.01 per share upon the attainment of regulatory exclusivity for atrasentan in the Territory. Such warrant will only be exercisable if and provided that SanReno obtains, before the 10-year anniversary of the closing of the formation of SanReno, the regulatory exclusivity for atrasentan in China for at least three years commencing from the New Drug Application approval by the National Medical Product Administration of China. The warrant will have a five-year In connection with the formation of SanReno in November 2021, Chinook also entered into a Shareholders Agreement (the “Shareholders Agreement”) providing for certain rights and obligations of SanReno and its shareholders. Pursuant to the Shareholders Agreement, Chinook has the right to designate an individual for election to the board of directors of SanReno and SanReno has agreed that certain specified events (including certain liquidation events) shall require the approval of shareholders of SanReno holding a supermajority of SanReno’s Series A preferred shares. The Shareholders Agreement terminates by mutual consent of the parties, and automatically terminates upon the dissolution of SanReno or immediately prior to the consummation of a qualified initial public offering. We account for the investment in SanReno in accordance with the provisions of ASC Topic 321, Investments – Equity Securities Pursuant to the terms of the Series A preferred stock, we are entitled to non-cumulative dividends at 8% of our initial investment, payable when and if declared by the board of directors of SanReno. Dividends from our investment in equity securities, if declared, are reflected in the consolidated statements of operations and comprehensive loss. There were no dividends declared during the three months ended March 31, 2022.

Equity Method Investment

Equity Method Investment	3 Months Ended
	Mar. 31, 2022
Equity Method Investments And Joint Ventures [Abstract]
Equity Method Investment	10. Equity Method Investment In April 2021, we entered into a definitive agreement with Sairopa B.V., a private company created by Van Herk Royalty B.V. and D.S. Chahal (the “Sairopa Investors”) to acquire certain non-renal assets of Chinook in exchange for preferred stock in Sairopa. We will hold such shares until such time as there is a liquidation event, as defined in the shareholders agreement, in Sairopa. In accordance with the CVR Agreement, 50% of any net proceeds received from this transaction by way of a liquidation event of Sairopa by October 4, 2030, net of deductions permitted under the CVR Agreement, including taxes and certain other expenses, will accrue to the benefit of the CVR holders. As of March 31, 2022, we own a 44% interest in Sairopa. We determined that we have the ability to exercise significant influence over Sairopa but do not have a controlling interest. Therefore, the investment in Sairopa was accounted for using the equity method. Judgment regarding the level of influence over each equity method investment includes considering key factors such as ownership interest, representation on the board of directors, and participation in policy-making decisions. The Sairopa Investors provided an initial capitalization of 12.5 million Euros. We recorded the equity method investment at $10.0 million, which is the fair value of the equity received by us in exchange for the non-renal assets. Our equity method investment was recorded at cost at inception and is adjusted each period for our share of the investee’s income or loss, which is reported in our consolidated statements of operations and comprehensive loss on a one quarter lag. We assess our equity method investment for impairment whenever events or changes in circumstances indicate that the carrying value of the investment may not be recoverable.

Collaboration and License Agree

Collaboration and License Agreements	3 Months Ended
	Mar. 31, 2022
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Collaboration and License Agreements	11. Collaboration and License Agreements SanReno Therapeutics In November 2021, we entered into the China License Agreement, pursuant to which we granted SanReno exclusive licenses under certain intellectual property to develop, manufacture and commercialize for atrasentan and BION-1301 in the Territory. Refer to Note 9 “Investment in Equity Securities” for further details on the agreements executed with SanReno. We evaluated the China License Agreement under ASC Topic 606 and determined that the China License Agreement represents a contract with a customer. We identified the following performance obligations: (i) the licenses to develop, manufacture and commercialize atrasentan and BION-1301; (ii) our obligation to transfer know-how for the licensed product candidates (“Technology Transfers”); (iii) manufacturing and supply services; and (iv) opt-in global studies. We determined that the preferred shares we received in SanReno of $40.0 million plus the warrant granted to us of $1.2 million constituted the entire consideration to be included in the total transaction price at the outset of the arrangement. Further, in determination of the performance obligations under the license agreements, the stand-alone selling prices of the performance obligations and our responsibility in the development activities have also been considered. Accordingly, the licenses, Technology Transfers, manufacturing and supply services, and opt-in global studies are all considered distinct performance obligations. Since both licensed product candidates are in the later stages of development, we determined that both licenses have significant stand-alone functionalities as of contract inception. SanReno can begin deriving benefit from the licenses prior to the Technology Transfers being completed. The Technology Transfers will be completed upon request of SanReno and are separate from the transfer of the licenses, which occurred at contract inception. The estimated standalone selling price for the Technology Transfers was determined by estimating the costs of satisfying the performance obligation, plus an appropriate margin for such services. Pursuant to the China License Agreement, SanReno will reimburse the manufacturing and supply services at cost plus a mark-up and will reimburse the opt-in global studies at cost, which represent pass-through fees from third-party vendors, including clinical research organization. Revenue attributable to the manufacturing and supply services and opt-in global studies will be recognized as incurred. For the three months ended March 31, 2022, we recognized revenue of $2.7 million under the China License Agreement for costs reimbursed related to opt-in global studies. We are also eligible to receive a progress-dependent milestone payment of up to approximately $25.0 million with respect to BION-1301. Under the China License Agreement, SanReno is also obligated to pay Chinook royalty payments at a percentage in the low teens based on net sales of atrasentan in the Territory on the portion of annual net sales in excess of a pre-determined amount, which royalty will be payable until the expiration of all licensed patents covering the sale of atrasentan in the Territory. The China License Agreement expires on a licensed product-by-licensed product basis on the latest of: (i) the expiration of the royalty term for atrasentan, (ii) the expiration of the last valid claim of a licensed patent for BION-1301 in the Territory. The parties may terminate the China License Agreement pursuant to terms specified in the agreement. Chinook and SanReno also have reciprocal rights of first negotiation in their respective territories for certain future kidney disease products developed or in-licensed by either company. Chinook retains full rights to atrasentan and BION-1301 outside of the Territory. The potential progress-dependent cash milestone payment that we are eligible to receive was excluded from the total transaction price, as the milestone amount is fully constrained based on the probability of achievement. Accordingly, any future milestone payment received under the agreement will be recorded upon or over a period following receipt. Further, we will apply the exception under ASC Topic 606 for variable consideration related to sales-or-usage based royalties received in exchange for licensed intellectual property associated with atrasentan, therefore the royalties are not included in the transaction price until the licensee sells product. No progress-dependent milestone payments and royalties were earned during the three months ended March 31, 2022. AbbVie Ireland Unlimited Company In December 2019, we entered into a license agreement (the “License Agreement”) with AbbVie Ireland Unlimited Company (“AbbVie”), which granted us an exclusive license to develop and commercialize atrasentan, an endothelin receptor antagonist. Under the agreement, we assumed all global development and commercialization responsibilities for atrasentan. In consideration of the license and rights granted under the License Agreement, we made an upfront cash payment and issued 2.0 million shares of common stock for total consideration of $6.7 million to AbbVie. We concluded that this transaction should be accounted for as an asset purchase, and as such, recorded the associated expense within research and development expense in the statements of operations and comprehensive loss, as the product has not reached technological feasibility and does not have alternative future use. Under the License Agreement, we are obligated to make contingent development, regulatory and commercial milestone payments of up to a maximum of $135.0 million in the aggregate, as well as pay royalties on the worldwide net sales of licensed products ranging from upper-single-digit to high-teen percentages. We did not recognize any milestone payments for the three months ended March 31, 2022 and 2021. As of March 31, 2022 and December 31, 2021, we did not have any payable or receivable balances associated with the License Agreement. Merck In connection with the Merger, we became party to an agreement with Merck. The agreement sets forth the parties’ respective obligations for development, commercialization, regulatory and manufacturing and supply activities for antibody product candidates. All performance obligations of Aduro were completed prior to the Merger. We are eligible to receive future contingent payments, including up to $287.0 million in potential development milestone payments, and up to $135.0 million in commercial and net sales milestones for a product candidate. In addition, we are eligible to receive royalties at percentages in the mid-single digits to low teens based on net sales of the product. Future milestone payments and royalties will be recognized as revenue when earned as we have no performance obligations under this agreement. Any such milestones and royalties earned prior to October 4, 2030 will be payable by us to the CVR holders, net of deductions permitted under the CVR Agreement, including taxes and certain other expenses. A $10.0 million development milestone was earned in the fourth quarter of 2021 and received in the first quarter of 2022. We expect to pay this milestone, net of taxes and expenses, to the CVR holders in the second quarter of 2022. Eli Lilly and Company In connection with the Merger, we assumed an ongoing research collaboration and exclusive license agreement with Eli Lilly and Company (“Lilly”) for the research and development of novel immunotherapies for autoimmune and other inflammatory diseases. Our only remaining performance obligation under the agreement was to perform research services through 2021, for which we were reimbursed up to a specified amount. We are eligible to receive future contingent milestone payments of up to approximately $464.9 million per licensed product and tiered royalties on net sales at percentages in the single digits. We determined that the potential milestone payments are not considered probable of being achieved and, accordingly, such milestones will be recognized as revenue when earned. For the three months ended March 31, 2021, we recognized revenue of $0.4 million under the Lilly agreement.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies Leases We have a total of four operating leases as of March 31, 2022 with remaining lease terms of approximately 4 to 8 years. In June 2021, we entered into a sublease agreement for office space in Seattle, Washington (“Seattle Sublease”), which we use as our corporate headquarters. The Seattle Sublease commenced on July 1, 2021 and continues for a period of 58 months. The aggregate estimated base rent payments due over the remaining term of the Seattle Sublease is approximately $5.0 million. As of March 31, 2022, we are subleasing approximately 112,000 square feet in one of our facilities. Sublease income was $2.0 million and $1.4 million for the three months ended March 31, 2022 and 2021, respectively, which was netted against rent expense. Total sublease income to be earned, in aggregate, will be approximately $63.1 million over the remaining term of the sublease agreement. We maintain a letter of credit as security for a facility lease that expires in 2029. The letter of credit is collateralized by a certificate of deposit in the amount of $1.8 million, which is classified as long-term restricted cash in our condensed consolidated balance sheet as of March 31, 2022. Additionally, we maintain a letter of credit as a security deposit for a facility lease that expires in 2026. The letter of credit is collateralized by a certificate of deposit in the amount of $0.3 million, which is classified as long-term restricted cash in our condensed consolidated balance sheet as of March 31, 2022. The maturity of our operating lease liabilities as of March 31, 2022 is as follows (in thousands): Undiscounted Lease Payments Amounts 2022 (remaining nine months) $ 5,684 2023 7,716 2024 7,871 2025 8,030 2026 7,179 Thereafter 18,934 Total undiscounted lease payments 55,414 Present value adjustment (12,372 ) Total net lease liability $ 43,042 Net lease liability - current $ 4,581 Net lease liability - non-current 38,461 Total net lease liability $ 43,042 Rent expense recognized for operating leases was $2.3 million and $2.1 million for the three months ended March 31, 2022 and 2021, respectively. Variable lease payments, including non-lease components such as common area maintenance fees, recognized as rent expense for operating leases were $0.8 million and less than $0.6 million for the three months ended March 31, 2022 and 2021, respectively. The following summarizes additional information related to our operating leases: March 31, 2022 December 31, 2021 Weighted-average remaining lease terms (in years) Operating leases 7.2 7.4 Weighted-average discount rate Operating leases 7.5% 7.5% Indemnification Agreements In the ordinary course of business, we enter into agreements that may include indemnification provisions. Pursuant to such agreements, we may indemnify, hold harmless and defend an indemnified party for losses suffered or incurred by the indemnified party. Some of the provisions will limit losses to those arising from third party actions. In some cases, the indemnification will continue after the termination of the agreement. The maximum potential amount of future payments we could be required to make under these provisions is not determinable. We have never incurred material costs to defend lawsuits or settle claims related to these indemnification provisions. We have also entered into indemnification agreements with our directors and officers that require us , among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers to the fullest extent permitted by Delaware corporate law. We currently maintain directors’ and officers’ liability insurance. Legal Proceedings From time to time, we may become involved in litigation relating to claims arising from the ordinary course of business. Management believes that there are no actions pending against us currently, the ultimate disposition of which would have a material adverse effect on our results of operations, financial condition or cash flows. Other Commitments We have various manufacturing, clinical, research and other contracts with vendors in the conduct of the normal course of our business. All contracts are terminable, with varying provisions regarding termination. If a contract with a specific vendor were to be terminated, we would only be obligated for the products or services that we had received at the time the termination became effective as well as non-cancelable and non-refundable obligations, including payment obligations for costs or expenses incurred by the vendor for products or services before the termination became effective. In the case of terminating a clinical trial agreement at a particular site, we would also be obligated to provide continued support for appropriate medical procedures at that site until completion or termination.

Common Stock

Common Stock	3 Months Ended
	Mar. 31, 2022
Equity [Abstract]
Common Stock	13. Common Stock At-the-Market Sales Agreement In April 2021, we entered into an “at-the-market” sales agreement (the “2021 Sales Agreement”), with Cantor Fitzgerald & Co. and SVB Leerink LLC, through which we may offer and sell shares of our common stock having an aggregate offering of up to $75.0 million through our sales agents, Cantor Fitzgerald & Co. and SVB Leerink LLC. We will pay the sales agents a commission of up to 3% of the gross proceeds of sales made through the 2021 Sales Agreement. As of March 31, 2022, we have $40.0 million remaining under the 2021 Sales Agreement, which is subject to the continued effectiveness of our shelf registration statement on Form S-3 (Registration No. 333-255099) that expires on April 7, 2024, or upon an effective replacement shelf registration statement Restricted Stock Awards (“RSAs”) The following table summarizes RSA activity: RSAs Outstanding Number of RSAs (in thousands) Weighted- Average Grant Date Fair Value Per Share Balance—December 31, 2021 99 $ 0.00034 Vested (23 ) 0.00034 Balance—March 31, 2022 76 $ 0.00034 The fair value of RSAs vested during the three months ended March 31, 2022 and 2021 was $0.3 million and $0.4 million, respectively.

Stock-Based Compensation

Stock-Based Compensation	3 Months Ended
	Mar. 31, 2022
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	14. Stock-based Compensation Equity Incentive Plans In February 2019, Private Chinook adopted the 2019 Equity Incentive Plan (the “2019 Plan”). In connection with the Merger, we assumed Aduro’s two equity incentive plans, the 2015 Equity Incentive Plan (the “2015 Plan”) and the 2009 Stock Incentive Plan (the “2009 Plan,” and collectively the “Aduro Plans” and together with the 2019 Plan, the “Plans”). No additional grants may be made from the 2009 Plan; however, shares subject to awards granted under the 2009 Plan re main subject to the terms of the 2009 Plan . As of March 31, 2022 and December 31, 2021, there were 1.9 million and 1.4 million shares available for future grant, respectively. In connection with the Merger, we assumed Aduro’s 2015 employee stock purchase plan (“2015 ESPP”). As of March 31, 2022 and December 31, 2021, there were 1.2 million and 0.7 million shares available for future issuance under the 2015 ESPP, respectively. Stock option activity under the Plans is set forth below: Number of Shares Underlying Options (in thousands) Weighted- Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Balance—December 31, 2021 5,842 $ 12.73 7.0 $ 34,928 Granted 1,624 13.03 Exercised (245 ) 8.37 Canceled or forfeited (278 ) 8.13 Balance—March 31, 2022 6,943 $ 13.13 7.5 $ 36,350 Options exercisable—March 31, 2022 2,651 $ 14.83 5.1 $ 17,638 Options vested and expected to vest—March 31, 2022 6,943 $ 13.13 7.5 $ 36,350 The aggregate intrinsic values of options outstanding, exercisable, and vested and expected to vest were calculated as the difference between the exercise price of the options and the market price for shares of our common stock as of March 31, 2022. Options for 0.2 million and 0.1 million shares of our common stock were exercised during the three months ended March 31, 2022 and 2021, respectively, with an intrinsic value of $1.6 million and $1.0 million, respectively. Restricted stock unit (“RSU”) activity under the Plans is set forth below: RSUs Outstanding Number of RSUs (in thousands) Weighted- Average Grant Date Fair Share Balance—December 31, 2021 823 $ 14.76 Granted 532 13.10 Vested (112 ) 15.20 Forfeited (36 ) 15.07 Balance—March 31, 2022 1,207 $ 13.98 The total fair value of RSUs that vested in the three months ended March 31, 2022 was $1.5 million and was not material for the three months ended March 31, 2021. Valuation Assumptions The weighted-average assumptions used to estimate the fair value of stock options using the Black-Scholes option-pricing model and the resulting weighted-average grant date fair value were as follows: Three Months Ended March 31, 2022 2021 Assumptions: Expected term (in years) 6.2 6.1 Volatility 77.8% 79.2% Risk-free interest rate 1.7% 0.7% Dividend yield — — Fair Value: Weighted-average grant date fair value per share $ 8.94 $ 10.33 The weighted-average assumptions used to estimate the fair value of our common stock to be issued under the 2015 ESPP using a Black-Scholes option-pricing model and the resulting weighted-average grant date fair value were as follows: Three Months Ended March 31, 2022 2021 Assumptions: Expected term (in years) 0.5 0.5 Volatility 64.9% 81.5% Risk-free interest rate 0.1% 0.1% Dividend yield — — Fair Value: Weighted-average grant date fair value per share $ 5.43 $ 5.42 Stock-based Compensation Expense Total stock Three Months Ended March 31, 2022 2021 Research and development $ 2,185 $ 1,028 General and administrative 2,084 1,450 Total stock-based compensation expense $ 4,269 $ 2,478 Total unrecognized stock-based compensation expense and the expected period over which such expense will be recognized are as follows ($ in millions): As of March 31, 2022 Stock options Unrecognized stock compensation expense $ 34.5 Weighted-average remaining vesting period (years) 2.9 RSU Unrecognized stock compensation expense $ 14.8 Weighted-average remaining vesting period (years) 2.3 ESPP Unrecognized stock compensation expense $ 0.1 Weighted-average remaining vesting period (years) 0.1

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	15. Income Taxes No income tax benefit or expense was recorded for the three months ended March 31, 2022 and 2021. Our effective tax rate is lower than the statutory tax rate of 21% primarily due to us maintaining a full valuation allowance against our net deferred tax assets.

Net Loss Per Common Share

Net Loss Per Common Share	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Net Loss Per Common Share	16. Net Loss per Common Share The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders, which excludes unvested restricted shares and shares which are legally outstanding, but subject to repurchase by us (in thousands, except per share amounts): Three Months Ended March 31, 2022 2021 Numerator: Net loss attributable to common stockholders $ (31,684 ) $ (37,215 ) Denominator: Weighted-average shares outstanding 58,428 42,319 Less: weighted-average unvested restricted shares and shares subject to repurchase (88 ) (183 ) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 58,340 42,136 Net loss per share attributable to common stockholders, basic and diluted $ (0.54 ) $ (0.88 ) As of March 31, 2022, 3.6 million pre-funded warrants to purchase common stock, issued in connection with the November 2021 public offering, were included in the weighted-average shares outstanding used in the calculation of basic and diluted net loss per share. Refer to Note 13 “Common Stock” in our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on March 17, 2022 for more information. The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the period presented because including them would have been antidilutive (in thousands): March 31, 2022 2021 Common stock warrants — 3 Unvested RSUs 1,207 793 Unvested RSAs 76 172 Options to purchase common stock 6,943 6,211 Total 8,226 7,179

Basis of Presentation and Con_2

Basis of Presentation and Consolidation, Use of Estimates and Recent Accounting Pronouncements (Policies)	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation and Consolidation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and follow the requirements of the Securities and Exchange Commission (“SEC”) for interim reporting. As permitted under those rules, certain footnotes or other financial information that are normally required by U.S. GAAP have been condensed or omitted, and accordingly the unaudited condensed consolidated financial statements do not include all of the information and notes required by U.S. GAAP for complete financial statements. These financial statements have been prepared on the same basis as our annual financial statements and, in the opinion of management, reflect all adjustments (consisting only of normal recurring adjustments) that are necessary for a fair presentation of financial information. The results of operations for the three months ended March 31, 2022 are not necessarily indicative of the results to be expected for the year ending December 31, 2022 or for any other interim period or for any other future year. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited consolidated financial statements and the related notes thereto for the year ended December 31, 2021 included in our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on March 17, 2022. The condensed consolidated financial statements include the accounts of Chinook Therapeutics, Inc. and our wholly-owned subsidiaries. All intercompany transactions and balances have been eliminated.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements as well as the reported amounts of expenses during the reporting periods. Such estimates include the valuation of intangible assets, acquired property and equipment, investments, contingent value rights (“CVR”) liability, contingent consideration liability, lease right-of-use assets, and lease obligations, as well as
Risks and Uncertainties	Risks and Uncertainties We are subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, protection of proprietary technology, dependence on key personnel, reliance on single-source vendors and collaborators, availability of raw materials, patentability of our products and processes and clinical efficacy and safety of our products under development, compliance with government regulations and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical studies, clinical trials and regulatory approval, prior to commercialization. These efforts will require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting. Our product candidates are still in development and, to date, none of our product candidates have been approved for sale and, therefore, we have not generated any revenue from product sales. There can be no assurance that our research and development will be successfully completed, that adequate protection for our intellectual property will be obtained or maintained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if our product development efforts are successful, it is uncertain when, if ever, we will generate revenue from product sales. We operate in an environment of rapid technological change and substantial competition from other pharmaceutical and biotechnology companies. In addition, we are dependent upon the services of our employees, consultants and other third parties. Moreover, the current COVID-19 pandemic, which is impacting worldwide economic activity, poses risk that we or our employees, contractors, suppliers, and other partners may be prevented from conducting business activities for an indefinite period of time which may delay the start-up and conduct of our clinical trials, and negatively impact manufacturing and testing activities performed by third parties. Any significant delays may
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recent Accounting Pronouncements, Not Yet Adopted In June 2016, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standard Update (“ASU”) No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In May 2021, the FASB issued ASU No. 2021-04, Earnings Per Share (Topic 260), Debt—Modifications and Extinguishments (Subtopic 470-50), Compensation—Stock Compensation (Topic 718), and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815- 40)

Cash, Cash Equivalents and Ma_2

Cash, Cash Equivalents and Marketable Securities (Tables)	3 Months Ended
	Mar. 31, 2022
Cash And Cash Equivalents [Abstract]
Summary of Cash, Cash Equivalents and Marketable Securities	Cash, cash equivalents and marketable securities consisted of the following (in thousands): March 31, 2022 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash and cash equivalents: Cash $ 42,703 $ — $ — $ 42,703 Money market funds 25,506 — — 25,506 Commercial paper 30,287 — (2 ) 30,285 U.S. government and agency securities 5,006 — — 5,006 Total cash and cash equivalents $ 103,502 $ — $ (2 ) $ 103,500 Marketable securities: Commercial paper $ 33,550 $ 1 $ (27 ) $ 33,524 U.S. government and agency securities 128,214 1 (1,001 ) 127,214 Corporate debt securities 66,487 — (693 ) 65,794 Total marketable securities $ 228,251 $ 2 $ (1,721 ) $ 226,532 December 31, 2021 Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Value Cash and cash equivalents: Cash $ 44,499 $ — $ — $ 44,499 Money market funds 117,023 — — 117,023 Commercial paper 16,898 — (1 ) 16,897 Corporate debt securities 3,306 — (1 ) 3,305 Total cash and cash equivalents $ 181,726 $ — $ (2 ) $ 181,724 Marketable securities: Commercial paper $ 34,978 $ — $ (10 ) $ 34,968 U.S. government and agency securities 85,309 1 (88 ) 85,222 Corporate debt securities 53,172 4 (38 ) 53,138 Total marketable securities $ 173,459 $ 5 $ (136 ) $ 173,328
Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Marketable Securities by Contractual Maturity	The amortized cost and estimated fair value of our available-for-sale marketable securities by contractual maturity are summarized below as of March 31, 2022 (in thousands): Amortized Cost Unrealized Gains Unrealized Losses Estimated Fair Mature in one year or less $ 173,306 $ 2 $ (709 ) $ 172,599 Mature after one year through two years 54,945 — (1,012 ) 53,933 Total available-for-sale marketable securities $ 228,251 $ 2 $ (1,721 ) $ 226,532

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2022
Fair Value Disclosures [Abstract]
Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables present information about our financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): March 31, 2022 Level 1 Level 2 Level 3 Total Assets: Cash and cash equivalents: Cash and money market funds $ 68,209 $ — $ — $ 68,209 Commercial paper — 30,285 — 30,285 U.S. government and agency securities — 5,006 5,006 Total cash and cash equivalents 68,209 35,291 — 103,500 Marketable securities: Commercial paper — 33,524 — 33,524 U.S. government and agency securities — 127,214 — 127,214 Corporate debt securities — 65,794 — 65,794 Total marketable securities — 226,532 — 226,532 Total fair value of assets $ 68,209 $ 261,823 $ — $ 330,032 Liabilities: Contingent value rights liability $ — $ — $ 33,963 $ 33,963 Contingent consideration liability — — 4,750 4,750 Total fair value of liabilities $ — $ — $ 38,713 $ 38,713 December 31, 2021 Level 1 Level 2 Level 3 Total Assets: Cash and cash equivalents: Cash and money market funds $ 161,522 $ — $ — $ 161,522 Commercial paper — 16,897 — 16,897 Corporate debt securities — 3,305 — 3,305 Total cash and cash equivalents 161,522 20,202 — 181,724 Marketable securities: Commercial paper — 34,968 — 34,968 U.S. government and agency securities — 85,222 — 85,222 Corporate debt securities — 53,138 — 53,138 Total marketable securities — 173,328 — 173,328 Total fair value of assets $ 161,522 $ 193,530 $ — $ 355,052 Liabilities: Contingent value rights liability $ — $ — $ 34,591 $ 34,591 Contingent consideration liability — — 5,160 5,160 Total fair value of liabilities $ — $ — $ 39,751 $ 39,751
Summary of Changes in Fair Value of Level 3 Financial Instruments	The following table presents a summary of the changes in the fair value of our Level 3 financial instruments (in thousands): Contingent Value Rights Liability Contingent Consideration Liability Balance at December 31, 2021 $ 34,591 $ 5,160 Net change in fair value upon remeasurement (628 ) (410 ) Balance at March 31, 2022 $ 33,963 $ 4,750

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2022
Property Plant And Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): March 31, December 31, 2022 2021 Research and lab equipment $ 3,493 $ 3,366 Computer equipment and software 1,266 1,497 Furniture and fixtures 1,349 1,224 Leasehold improvements 16,982 16,976 Total property and equipment 23,090 23,063 Total accumulated depreciation (4,827 ) (4,128 ) Property and equipment, net $ 18,263 $ 18,935

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2022
Goodwill And Intangible Assets Disclosure [Abstract]
Schedule of Intangible Assets	The gross carrying amounts and net book value of intangible assets were as follows (in thousands): March 31, 2022 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: Acquired license agreement $ 26,685 $ 2,360 $ 24,325 In-place lease 1,433 178 1,255 Total intangible assets with finite lives 28,118 2,538 25,580 Acquired in-process research & development ("IPR&D") assets 36,550 — 36,550 Total intangible and acquired IPR&D assets $ 64,668 $ 2,538 $ 62,130 December 31, 2021 Gross Amount Accumulated Amortization Net Book Value Intangible assets with finite lives: Acquired license agreement $ 26,685 $ 1,968 $ 24,717 In-place lease 1,433 141 1,292 Total intangible assets with finite lives 28,118 2,109 26,009 Acquired IPR&D assets 36,550 — 36,550 Total intangible and acquired IPR&D assets $ 64,668 $ 2,109 $ 62,559
Schedule of Finite-Lived Intangible Assets Estimated Future Amortization Expense	Based on finite-lived intangible assets recorded as of March 31, 2022, the estimated future amortization expense for the next five years is as follows (in thousands): Year Ending December 31, Estimated Amortization Expense 2022 (remaining nine months) $ 1,293 2023 1,733 2024 1,733 2025 1,733 2026 1,733 Thereafter 17,355

Accrued and Other Current Lia_2

Accrued and Other Current Liabilities (Tables)	3 Months Ended
	Mar. 31, 2022
Accrued Liabilities And Other Liabilities [Abstract]
Schedule of Accrued and Other Current Liabilities	Accrued and other current liabilities consisted of the following (in thousands): March 31 December 31, 2022 2021 Research and development costs $ 7,703 $ 8,397 Compensation and benefits 3,478 6,455 Sublease rent and security deposit 1,072 1,067 Business taxes and licensing fees 455 421 Consulting and outside services 208 424 Other 30 340 Total accrued and other current liabilities $ 12,946 $ 17,104

Commitments and Contingencies (

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2022
Commitments And Contingencies Disclosure [Abstract]
Schedule of Maturity of Operating Lease Liabilities	The maturity of our operating lease liabilities as of March 31, 2022 is as follows (in thousands): Undiscounted Lease Payments Amounts 2022 (remaining nine months) $ 5,684 2023 7,716 2024 7,871 2025 8,030 2026 7,179 Thereafter 18,934 Total undiscounted lease payments 55,414 Present value adjustment (12,372 ) Total net lease liability $ 43,042 Net lease liability - current $ 4,581 Net lease liability - non-current 38,461 Total net lease liability $ 43,042
Schedule of Additional Information Related to Operating Leases	The following summarizes additional information related to our operating leases: March 31, 2022 December 31, 2021 Weighted-average remaining lease terms (in years) Operating leases 7.2 7.4 Weighted-average discount rate Operating leases 7.5% 7.5%

Common Stock (Tables)

Common Stock (Tables)	3 Months Ended
	Mar. 31, 2022
Restricted Stock Awards (RSAs)
Summary of RSA Activity	The following table summarizes RSA activity: RSAs Outstanding Number of RSAs (in thousands) Weighted- Average Grant Date Fair Value Per Share Balance—December 31, 2021 99 $ 0.00034 Vested (23 ) 0.00034 Balance—March 31, 2022 76 $ 0.00034

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Summary of Stock Option Activity	Stock option activity under the Plans is set forth below: Number of Shares Underlying Options (in thousands) Weighted- Average Exercise Price Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Balance—December 31, 2021 5,842 $ 12.73 7.0 $ 34,928 Granted 1,624 13.03 Exercised (245 ) 8.37 Canceled or forfeited (278 ) 8.13 Balance—March 31, 2022 6,943 $ 13.13 7.5 $ 36,350 Options exercisable—March 31, 2022 2,651 $ 14.83 5.1 $ 17,638 Options vested and expected to vest—March 31, 2022 6,943 $ 13.13 7.5 $ 36,350
Summary of Restricted Stock Unit ("RSU") Activity	Restricted stock unit (“RSU”) activity under the Plans is set forth below: RSUs Outstanding Number of RSUs (in thousands) Weighted- Average Grant Date Fair Share Balance—December 31, 2021 823 $ 14.76 Granted 532 13.10 Vested (112 ) 15.20 Forfeited (36 ) 15.07 Balance—March 31, 2022 1,207 $ 13.98
Schedule of Weighted-average Assumptions Used to Estimate Fair Value of Stock Options Using Black Scholes Option-Pricing Model	The weighted-average assumptions used to estimate the fair value of stock options using the Black-Scholes option-pricing model and the resulting weighted-average grant date fair value were as follows: Three Months Ended March 31, 2022 2021 Assumptions: Expected term (in years) 6.2 6.1 Volatility 77.8% 79.2% Risk-free interest rate 1.7% 0.7% Dividend yield — — Fair Value: Weighted-average grant date fair value per share $ 8.94 $ 10.33
Summary of Stock-Based Compensation	Total stock Three Months Ended March 31, 2022 2021 Research and development $ 2,185 $ 1,028 General and administrative 2,084 1,450 Total stock-based compensation expense $ 4,269 $ 2,478
Total Unrecognized Stock-Based Compensation Expense and Expected Period Over Which Such Expense Will Be Recognized	Total unrecognized stock-based compensation expense and the expected period over which such expense will be recognized are as follows ($ in millions): As of March 31, 2022 Stock options Unrecognized stock compensation expense $ 34.5 Weighted-average remaining vesting period (years) 2.9 RSU Unrecognized stock compensation expense $ 14.8 Weighted-average remaining vesting period (years) 2.3 ESPP Unrecognized stock compensation expense $ 0.1 Weighted-average remaining vesting period (years) 0.1
2015 ESPP
Schedule of Black Scholes Option-Pricing Model	The weighted-average assumptions used to estimate the fair value of our common stock to be issued under the 2015 ESPP using a Black-Scholes option-pricing model and the resulting weighted-average grant date fair value were as follows: Three Months Ended March 31, 2022 2021 Assumptions: Expected term (in years) 0.5 0.5 Volatility 64.9% 81.5% Risk-free interest rate 0.1% 0.1% Dividend yield — — Fair Value: Weighted-average grant date fair value per share $ 5.43 $ 5.42

Net Loss per Common Share (Tabl

Net Loss per Common Share (Tables)	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Net Loss Per Share	The following table sets forth the computation of basic and diluted net loss per share attributable to common stockholders, which excludes unvested restricted shares and shares which are legally outstanding, but subject to repurchase by us (in thousands, except per share amounts): Three Months Ended March 31, 2022 2021 Numerator: Net loss attributable to common stockholders $ (31,684 ) $ (37,215 ) Denominator: Weighted-average shares outstanding 58,428 42,319 Less: weighted-average unvested restricted shares and shares subject to repurchase (88 ) (183 ) Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted 58,340 42,136 Net loss per share attributable to common stockholders, basic and diluted $ (0.54 ) $ (0.88 )
Schedule of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share	As of March 31, 2022, 3.6 million pre-funded warrants to purchase common stock, issued in connection with the November 2021 public offering, were included in the weighted-average shares outstanding used in the calculation of basic and diluted net loss per share. Refer to Note 13 “Common Stock” in our Annual Report on Form 10-K for the year ended December 31, 2021 filed with the SEC on March 17, 2022 for more information. The following outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the period presented because including them would have been antidilutive (in thousands): March 31, 2022 2021 Common stock warrants — 3 Unvested RSUs 1,207 793 Unvested RSAs 76 172 Options to purchase common stock 6,943 6,211 Total 8,226 7,179

Basis of Presentation and Con_3

Basis of Presentation and Consolidation, Use of Estimates and Recent Accounting Pronouncements - Additional Information (Details)	Mar. 31, 2022
Accounting Policies [Abstract]
Change in accounting principle, accounting standards update, adopted	true
Change in accounting principle, Accounting Standards Update, Adoption Date	Jan. 1, 2022
Change in accounting principle, accounting standards update, immaterial effect	true

Reverse Merger and Contingent_2

Reverse Merger and Contingent Value Rights - Additional Information (Details)	3 Months Ended
	Mar. 31, 2022
Business Combinations [Abstract]
Description of contingent value rights granted	one CVR for each outstanding share of Aduro common stock

Cash, Cash Equivalents and Ma_3

Cash, Cash Equivalents and Marketable Securities - Summary of Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents, Amortized Cost	$ 103,502	$ 181,726
Cash and cash equivalents, Unrealized Losses	(2)	(2)
Cash and cash equivalents, Estimated Fair Value	103,500	181,724
Marketable securities, Amortized Cost	228,251	173,459
Marketable securities, Unrealized Gains	2	5
Marketable securities, Unrealized Losses	(1,721)	(136)
Marketable securities, Estimated Fair Value	226,532	173,328
Cash
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents, Amortized Cost	42,703	44,499
Cash and cash equivalents, Estimated Fair Value	42,703	44,499
Money Market Funds
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents, Amortized Cost	25,506	117,023
Cash and cash equivalents, Estimated Fair Value	25,506	117,023
Commercial Paper
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents, Amortized Cost	30,287	16,898
Cash and cash equivalents, Unrealized Losses	(2)	(1)
Cash and cash equivalents, Estimated Fair Value	30,285	16,897
Marketable securities, Amortized Cost	33,550	34,978
Marketable securities, Unrealized Gains	1
Marketable securities, Unrealized Losses	(27)	(10)
Marketable securities, Estimated Fair Value	33,524	34,968
U.S. Government and Agency Securities
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents, Amortized Cost	5,006
Cash and cash equivalents, Estimated Fair Value	5,006
Marketable securities, Amortized Cost	128,214	85,309
Marketable securities, Unrealized Gains	1	1
Marketable securities, Unrealized Losses	(1,001)	(88)
Marketable securities, Estimated Fair Value	127,214	85,222
Corporate Debt Securities
Cash And Cash Equivalents [Line Items]
Cash and cash equivalents, Amortized Cost		3,306
Cash and cash equivalents, Unrealized Losses		(1)
Cash and cash equivalents, Estimated Fair Value		3,305
Marketable securities, Amortized Cost	66,487	53,172
Marketable securities, Unrealized Gains		4
Marketable securities, Unrealized Losses	(693)	(38)
Marketable securities, Estimated Fair Value	$ 65,794	$ 53,138

Cash, Cash Equivalents and Ma_4

Cash, Cash Equivalents and Marketable Securities - Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Marketable Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value Disclosures [Abstract]
Mature in one year or less, Amortized Cost	$ 173,306
Mature after one year through two years, Amortized Cost	54,945
Marketable securities, Amortized Cost	228,251	$ 173,459
Mature in one year or less, Unrealized Gains	2
Total available-for-sale marketable securities, Unrealized Gains	2	5
Mature in one year or less, Unrealized Losses	(709)
Mature after one year through two years, Unrealized Losses	(1,012)
Total available-for-sale marketable securities, Unrealized Losses	(1,721)	(136)
Mature in one year or less, Estimated Fair Value	172,599
Mature after one year through two years, Estimated Fair Value	53,933
Total available-for-sale marketable securities, Estimated Fair Value	$ 226,532	$ 173,328

Cash, Cash Equivalents and Ma_5

Cash, Cash Equivalents and Marketable Securities - Additional Information (Details)	Mar. 31, 2022USD ($)
Cash And Cash Equivalents [Abstract]
Marketable securities in continuous unrealized loss position	$ 0
Investment in portfolio temporary impaired	$ 0

Fair Value Measurements - Finan

Fair Value Measurements - Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Assets:
Cash and cash equivalents, Estimated Fair Value	$ 103,500	$ 181,724
Marketable securities	226,532	173,328
Assets	330,032	355,052
Liabilities:
Liabilities	38,713	39,751
Contingent Value Rights Liability
Liabilities:
Liabilities	33,963	34,591
Contingent Consideration Liability
Liabilities:
Liabilities	4,750	5,160
Level 1
Assets:
Cash and cash equivalents, Estimated Fair Value	68,209	161,522
Assets	68,209	161,522
Level 2
Assets:
Cash and cash equivalents, Estimated Fair Value	35,291	20,202
Marketable securities	226,532	173,328
Assets	261,823	193,530
Level 3
Liabilities:
Liabilities	38,713	39,751
Level 3 | Contingent Value Rights Liability
Liabilities:
Liabilities	33,963	34,591
Level 3 | Contingent Consideration Liability
Liabilities:
Liabilities	4,750	5,160
Cash and Money Market Funds
Assets:
Cash and cash equivalents, Estimated Fair Value	68,209	161,522
Cash and Money Market Funds | Level 1
Assets:
Cash and cash equivalents, Estimated Fair Value	68,209	161,522
Commercial Paper
Assets:
Cash and cash equivalents, Estimated Fair Value	30,285	16,897
Marketable securities	33,524	34,968
Commercial Paper | Level 2
Assets:
Cash and cash equivalents, Estimated Fair Value	30,285	16,897
Marketable securities	33,524	34,968
Corporate Debt Securities
Assets:
Cash and cash equivalents, Estimated Fair Value		3,305
Marketable securities	65,794	53,138
Corporate Debt Securities | Level 2
Assets:
Cash and cash equivalents, Estimated Fair Value		3,305
Marketable securities	65,794	53,138
U.S. Government and Agency Securities
Assets:
Cash and cash equivalents, Estimated Fair Value	5,006
Marketable securities	127,214	85,222
U.S. Government and Agency Securities | Level 2
Assets:
Cash and cash equivalents, Estimated Fair Value	5,006
Marketable securities	$ 127,214	$ 85,222

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Changes in Fair Value of Level 3 Financial Instruments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)
Contingent Value Rights Liability
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Balance at December 31, 2021	$ 34,591
Net change in fair value upon remeasurement	(628)
Balance at March 31, 2022	33,963
Contingent Consideration Liability
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Balance at December 31, 2021	5,160
Net change in fair value upon remeasurement	(410)
Balance at March 31, 2022	$ 4,750

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Change in fair value of contingent consideration and contingent value rights liabilities	$ (1,038)	$ 1,839
CVR Agreement
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Change in fair value of contingent consideration and contingent value rights liabilities	$ (1,000)	$ 1,800

Property and Equipment, Net - S

Property and Equipment, Net - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Total property and equipment	$ 23,090	$ 23,063
Total accumulated depreciation	(4,827)	(4,128)
Property and equipment, net	18,263	18,935
Research and Lab Equipment
Property Plant And Equipment [Line Items]
Total property and equipment	3,493	3,366
Computer Equipment And Software
Property Plant And Equipment [Line Items]
Total property and equipment	1,266	1,497
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	1,349	1,224
Leasehold Improvements
Property Plant And Equipment [Line Items]
Total property and equipment	$ 16,982	$ 16,976

Property and Equipment, Net - A

Property and Equipment, Net - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Property Plant And Equipment [Line Items]
Property and equipment	$ 18,263		$ 18,935
Depreciation and amortization expense for property and equipment	900	$ 700
Canada
Property Plant And Equipment [Line Items]
Property and equipment	$ 2,900

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Goodwill And Intangible Assets [Line Items]
Goodwill	$ 117		$ 117
Amortization of intangible assets	$ 429	$ 420
Novartis
Goodwill And Intangible Assets [Line Items]
Intangible assets, weighted average period	16 years 8 months 12 days
Novartis | Minimum
Goodwill And Intangible Assets [Line Items]
Intangible assets, amortization period	9 years
Novartis | Maximum
Goodwill And Intangible Assets [Line Items]
Intangible assets, amortization period	17 years

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Finite Lived Intangible Assets, Gross Carrying Amount	$ 28,118	$ 28,118
Finite Lived Intangible Assets, Accumulated Amortization	2,538	2,109
Intangible assets, net	25,580	26,009
Intangible Assets, Gross Carrying Amount	64,668	64,668
Intangible assets, Net Book Value	62,130	62,559
Acquired in-process research & development ("IPR&D") assets
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Indefinite-Lived Intangible Assets, Gross Carrying Amount	36,550	36,550
Indefinite-Lived Intangible Assets, Net Book Value	36,550	36,550
Acquired license agreement
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Finite Lived Intangible Assets, Gross Carrying Amount	26,685	26,685
Finite Lived Intangible Assets, Accumulated Amortization	2,360	1,968
Intangible assets, net	24,325	24,717
In Place Lease
Schedule Of Finite And Indefinite Lived Intangible Assets [Line Items]
Finite Lived Intangible Assets, Gross Carrying Amount	1,433	1,433
Finite Lived Intangible Assets, Accumulated Amortization	178	141
Intangible assets, net	$ 1,255	$ 1,292

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Schedule of Finite-Lived Intangible Assets Estimated Future Amortization Expense (Details) $ in Thousands	Mar. 31, 2022USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
2022 (remaining nine months)	$ 1,293
2023	1,733
2024	1,733
2025	1,733
2026	1,733
Thereafter	$ 17,355

Accrued and Other Current Lia_3

Accrued and Other Current Liabilities - Schedule of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Accrued Liabilities And Other Liabilities [Abstract]
Research and development costs	$ 7,703	$ 8,397
Compensation and benefits	3,478	6,455
Sublease rent and security deposit	1,072	1,067
Business taxes and licensing fees	455	421
Consulting and outside services	208	424
Other	30	340
Total accrued and other current liabilities	$ 12,946	$ 17,104

Investment in Equity Securiti_2

Investment in Equity Securities - Additional Information (Details) - San Reno - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended
	Nov. 30, 2021	Mar. 31, 2022
Investment In Equity Securities [Line Items]
Investment in equity security, ownership percentage	50.00%
Investment in equity securities	$ 40,000,000
Warrants to purchase common shares	5
Exercise price of warrants	$ 0.01
Warrant exercise period	5 years
Fair value of warrant	$ 1,200,000
Equity securities invested amount	$ 40,000,000
Investment in equity security, remaining ownership percentage	50.00%
Investment in equity securities		$ 41,200,000
Impairment on investment		$ 0
Series A Preferred Stock
Investment In Equity Securities [Line Items]
Investment in equity securities	$ 40,000,000
Dividends percentage	8.00%

Equity Method Investment - Addi

Equity Method Investment - Additional Information (Details) - Sairopa B.V. € in Millions, $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2021USD ($)	Mar. 31, 2022	Apr. 30, 2021EUR (€)
Schedule Of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		44.00%
Equity method investment, initial capitalization | €			€ 12.5
Equity method investment, recorded | $	$ 10
Equity method investment, income or loss recorded term		one quarter lag
CVR Agreement
Schedule Of Equity Method Investments [Line Items]
Percentage of net proceeds received from transaction of liquidation event	50.00%

Collaboration and License Agr_2

Collaboration and License Agreements - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended
	Nov. 30, 2021	Dec. 31, 2019	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021
China License Agreement | San Reno
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Consideration received as preferred shares	$ 40,000,000
Consideration received as warrants	$ 1,200,000
Revenue recognized			$ 2,700,000
China License Agreement | San Reno | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Progress-dependent milestone receivable			25,000,000
AbbVie Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Common stock shares issued		2,000,000
Proceeds from issuance of common stock		$ 6,700,000
Milestone payment			0		$ 0
AbbVie Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent development, regulatory and commercial milestone payments			135,000,000
Merck
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized				$ 10,000,000
Merck | Maximum | Product Candidate
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates			287,000,000
Merck | Maximum | Product
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates			135,000,000
Lilly Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized					$ 400,000
Lilly Agreement | Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Milestone amount eligible to receive for products or product candidates			$ 464,900,000

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Details) $ in Millions	1 Months Ended	3 Months Ended
	Jun. 30, 2021USD ($)	Mar. 31, 2022USD ($)ft²LeaseFacility	Mar. 31, 2021USD ($)
Operating Leased Assets [Line Items]
Number of lease facility | LeaseFacility		4
Aggregate sublease income to be earned		$ 63.1
Lease expiration date		2029
Operating leases rent expense		$ 2.3	$ 2.1
Operating leases variable lease payments		0.8	0.6
Long-Term Restricted Cash
Operating Leased Assets [Line Items]
Security deposit		$ 1.8
Collateralized Certificate of Deposit
Operating Leased Assets [Line Items]
Lease expiration date		2026
Collateralized Certificate of Deposit | Long-Term Restricted Cash
Operating Leased Assets [Line Items]
Security deposit		$ 0.3
Seattle Sublease
Operating Leased Assets [Line Items]
Sublease agreement term	2021-06
Sublease commencement date	Jul. 1, 2021
Sublease period	58 months
Aggregate estimated base rent payments	$ 5
Sublease | C A
Operating Leased Assets [Line Items]
Total square footage of leased property | ft²		112,000
Sublease Income		$ 2	$ 1.4
Minimum
Operating Leased Assets [Line Items]
Operating lease, remaining lease term		5 years
Maximum
Operating Leased Assets [Line Items]
Operating lease, remaining lease term		8 years

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Maturity of Company's Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Commitments And Contingencies Disclosure [Abstract]
2022 (remaining nine months)	$ 5,684
2023	7,716
2024	7,871
2025	8,030
2026	7,179
Thereafter	18,934
Total undiscounted lease payments	55,414
Present value adjustment	(12,372)
Total net lease liability	43,042
Net lease liability - current	4,581	$ 4,401
Net lease liability - non-current	38,461	$ 39,589
Total net lease liability	$ 43,042

Commitments and Contingencies_3

Commitments and Contingencies - Schedule of Additional Information Related to Operating Leases (Details)	Mar. 31, 2022	Dec. 31, 2021
Weighted-average remaining lease terms (in years)
Operating leases	7 years 2 months 12 days	7 years 4 months 24 days
Weighted-average discount rate
Operating leases	7.50%	7.50%

Common Stock - Additional Infor

Common Stock - Additional Information (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Apr. 30, 2021	Mar. 31, 2022	Mar. 31, 2021
Restricted Stock Awards (RSAs)
Class Of Stock [Line Items]
Fair value of RSAs vested		$ 0.3	$ 0.4
At-the-Market Offering | 2021 Sales Agreement | Cantor Fitzgerald & Co. and SVB Leerink LLC
Class Of Stock [Line Items]
Commission on sales of common stock, percentage	3.00%
Aggregate offering available for issuance of common stock		$ 40
Agreement maturity date	Apr. 7, 2024
At-the-Market Offering | 2021 Sales Agreement | Maximum | Cantor Fitzgerald & Co. and SVB Leerink LLC
Class Of Stock [Line Items]
Aggregate offering available for issuance of common stock	$ 75

Common Stock - Summary of RSA A

Common Stock - Summary of RSA Activity (Details) - Restricted Stock Awards (RSAs)	3 Months Ended
	Mar. 31, 2022$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Restricted Stock, Beginning balance | shares	99
Number of Restricted Stock, Vested | shares	(23)
Number of Restricted Stock, Ending balance | shares	76
Weighted-Average Grant Date Fair Value per Share, Beginning Balance | $ / shares	$ 0.00034
Weighted-Average Grant Date Fair Value per Share, Vested | $ / shares	0.00034
Weighted-Average Grant Date Fair Value per Share, Ending Balance | $ / shares	$ 0.00034

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022USD ($)IncentivePlanshares	Mar. 31, 2021USD ($)shares	Dec. 31, 2021shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of equity incentive plans | IncentivePlan	2
Number of common shares, granted	1,624,000
Number of shares available for future grant	1,900,000		1,400,000
Common Stock options exercised	245,000	100,000
Intrinsic value of options exercised | $	$ 1.6	$ 1
Restricted Stock Units ("RSU")
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total fair value of restricted stock units vested during the period | $	$ 1.5
2009 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common shares, granted	0
2015 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for future grant	1,200,000		700,000

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares Underlying Options, Beginning balance	5,842
Number of Shares Underlying Options, Granted	1,624
Number of Shares Underlying Options, Exercised	(245)	(100)
Number of Shares Underlying Options, Cancelled or forfeited	(278)
Number of Shares Underlying Options, Ending balance	6,943		5,842
Number of Shares Underlying Options, Options exercisable	2,651
Number of Shares Underlying Options, Vested and expected to vest	6,943
Options Outstanding, Weighted-Average Exercise Price, Beginning balance	$ 12.73
Options Outstanding, Weighted-Average Exercise Price, Granted	13.03
Options Outstanding, Weighted-Average Exercise Price, Exercised	8.37
Options Outstanding, Weighted-Average Exercise Price, Canceled or forfeited	8.13
Options Outstanding, Weighted-Average Exercise Price, Ending balance	13.13		$ 12.73
Options Outstanding, Weighted-Average Exercise Price, Options exercisable	14.83
Options Outstanding, Weighted-Average Exercise Price, Options vested and expected to vest	$ 13.13
Options Outstanding, Weighted Average Remaining Contractual Term, Beginning balance	7 years 6 months		7 years
Options exercisable, Weighted Average Remaining Contractual Term	5 years 1 month 6 days
Options vested and expected to vest, Weighted Average Remaining Contractual Term	7 years 6 months
Options Outstanding, Aggregate Intrinsic Value, Balance	$ 34,928
Options Outstanding, Aggregate Intrinsic Value, Ending	36,350		$ 34,928
Options Outstanding, Aggregate Intrinsic Value, Options exercisable-March 31, 2022	17,638
Options Outstanding, Aggregate Intrinsic Value, Options vested and expected to vest-March 31, 2022	$ 36,350

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Restricted Stock Units ("RSU") Activity (Details) - Restricted Stock Units ("RSU") shares in Thousands	3 Months Ended
	Mar. 31, 2022$ / sharesshares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of Restricted Stock, Beginning balance | shares	823
Number of Restricted Stock, Granted | shares	532
Number of Restricted Stock, Vested | shares	(112)
Number of Restricted Stock, Forfeited | shares	(36)
Number of Restricted Stock, Ending balance | shares	1,207
Weighted-Average Grant Date Fair Value per Share, Beginning Balance | $ / shares	$ 14.76
Weighted-Average Grant Date Fair Value Per Share, Granted | $ / shares	13.10
Weighted-Average Grant Date Fair Value per Share, Vested | $ / shares	15.20
Weighted-Average Grant Date Fair Value Per Share, Forfeited | $ / shares	15.07
Weighted-Average Grant Date Fair Value per Share, Ending Balance | $ / shares	$ 13.98

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Weighted-average Assumptions Used to Estimate Fair Value of Stock Options Using Black Scholes Option-Pricing Model (Details) - Stock Options - $ / shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 2 months 12 days	6 years 1 month 6 days
Volatility	77.80%	79.20%
Risk-free interest rate	1.70%	0.70%
Weighted-average grant date fair value per share	$ 8.94	$ 10.33

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Black Scholes Option-Pricing Model (Details) - 2015 ESPP - $ / shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months	6 months
Volatility	64.90%	81.50%
Risk-free interest rate	0.10%	0.10%
Weighted-average grant date fair value per share	$ 5.43	$ 5.42

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 4,269	$ 2,478
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	2,185	1,028
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 2,084	$ 1,450

Stock-Based Compensation - Tota

Stock-Based Compensation - Total Unrecognized Stock-Based Compensation Expense and Expected Period Over Which Such Expense Will Be Recognized (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022USD ($)
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized stock compensation expense	$ 34.5
Weighted-average remaining vesting period (years)	2 years 10 months 24 days
Restricted Stock Units ("RSU")
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining vesting period (years)	2 years 3 months 18 days
Unrecognized stock compensation expense	$ 14.8
2015 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining vesting period (years)	1 month 6 days
Unrecognized stock compensation expense	$ 0.1

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income tax expense (benefit)	$ 0	$ 0
Statutory tax rate	21.00%

Net Loss per Common Share - Sch

Net Loss per Common Share - Schedule of Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Net loss	$ (31,684)	$ (37,215)
Weighted-average shares outstanding	58,428	42,319
Less: weighted-average unvested restricted shares and shares subject to repurchase	(88)	(183)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic and diluted	58,340	42,136
Net loss per share attributable to common stockholders, basic and diluted	$ (0.54)	$ (0.88)

Net Loss Per Common Share - Add

Net Loss Per Common Share - Additional Information (Details) shares in Millions	3 Months Ended
	Mar. 31, 2022shares
Pre-Funded Warrants
Earnings Per Share Basic [Line Items]
Pre-Funded warrants to purchase common stock	3.6

Net Loss per Common Share - S_2

Net Loss per Common Share - Schedule of Potentially Dilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share would have been antidilutive	8,226	7,179
Common Stock Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share would have been antidilutive		3
Unvested RSUs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share would have been antidilutive	1,207	793
Unvested RSAs
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share would have been antidilutive	76	172
Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential dilutive securities excluded from diluted net loss per share would have been antidilutive	6,943	6,211