Global Blood Therapeutics (GBT) 10-Q 8 Aug 22 2022 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2022	Aug. 04, 2022
Cover [Abstract]
Document Type	10-Q
Document Period End Date	Jun. 30, 2022
Entity Registrant Name	Global Blood Therapeutics, Inc.
Entity Filer Category	Large Accelerated Filer
Trading Symbol	GBT
Entity Emerging Growth Company	false
Entity Small Business	false
Document Transition Report	false
Entity Common Stock, Shares Outstanding		67,463,704
Document Quarterly Report	true
Entity Interactive Data Current	Yes
Entity Current Reporting Status	Yes
Entity File Number	001-37539
Entity Tax Identification Number	27-4825712
Entity Shell Company	false
Entity Address, Address Line One	181 Oyster Point Boulevard
Entity Address, City or Town	South San Francisco
Entity Address, State or Province	CA
City Area Code	650
Local Phone Number	741-7700
Entity Address, Postal Zip Code	94080
Title of 12(b) Security	Common Stock
Security Exchange Name	NASDAQ
Entity Incorporation, State or Country Code	DE
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q2
Entity Central Index Key	0001629137
Current Fiscal Year End Date	--12-31

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 261,152	$ 684,717
Short-term marketable securities	256,006	0
Accounts receivable, net	29,765	28,800
Inventories	65,816	58,202
Prepaid expenses and other current assets	27,272	30,251
Total current assets	640,011	801,970
Long-term marketable securities	146,863	50,057
Property and equipment, net	32,425	34,918
Operating lease right-of-use assets	46,497	48,015
Restricted cash	2,432	2,436
Other assets, noncurrent	2,214	1,812
Total assets	870,442	939,208
Current liabilities:
Accounts payable	8,260	15,097
Accrued liabilities	53,266	39,297
Accrued compensation	25,187	27,712
Other liabilities, current	6,379	5,892
Total current liabilities	93,092	87,998
Long-term debt, net	247,130	246,352
Convertible debt, net	334,815	334,089
Operating lease liabilities, noncurrent	70,322	73,506
Other liabilities, noncurrent	6,723	853
Total liabilities	752,082	742,798
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.001 par value, 5,000,000 shares authorized as of June 30, 2022 (unaudited) and December 31, 2021; no shares issued and outstanding	0	0
Common stock, $0.001 par value, 150,000,000 shares authorized as of June 30, 2022 (unaudited) and December 31, 2021, respectively; 67,257,761 and 64,636,641 shares issued and outstanding as of June 30, 2022 (unaudited) and December 31, 2021, respectively	67	65
Additional paid-in capital	1,575,719	1,485,805
Accumulated other comprehensive income	(3,973)	100
Accumulated deficit	(1,453,453)	(1,289,560)
Total stockholders' equity	118,360	196,410
Total liabilities and stockholders' equity	$ 870,442	$ 939,208

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Jun. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	67,272,761	64,636,641
Common stock, shares outstanding	67,272,761	64,636,641

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Revenues [Abstract]
Product sales, net	$ 71,550	$ 47,555	$ 126,710	$ 86,598
Costs and operating expenses:
Cost of sales	1,413	748	2,468	1,332
Research and development	64,775	51,784	117,608	102,641
Selling, general and administrative	81,088	61,093	155,622	120,059
Total costs and operating expenses	147,276	113,625	275,698	224,032
Loss from operations	(75,726)	(66,070)	(148,988)	(137,434)
Other income (expense):
Interest income	1,664	164	2,164	493
Interest expense	(8,402)	(3,677)	(16,607)	(7,366)
Other income (expense), net	186	21	(100)	(62)
Total other income (expense,), net	(6,552)	(3,492)	(14,543)	(6,935)
Loss before income taxes	(82,278)	(69,562)	(163,531)	(144,369)
Provision for income taxes	192	30	362	153
Net loss	(82,470)	(69,592)	(163,893)	(144,522)
Other comprehensive loss:
Net unrealized gain on marketable securities, net of tax	(1,711)	(78)	(3,626)	(259)
Cumulative translation adjustment	(300)	259	(446)	259
Total other comprehensive expense, net	(2,011)	181	(4,072)	0
Comprehensive loss	$ (84,481)	$ (69,411)	$ (167,965)	$ (144,522)
Basic net loss per common share	$ (1.26)	$ (1.12)	$ (2.51)	$ (2.32)
Diluted net loss per common share	$ (1.26)	$ (1.12)	$ (2.51)	$ (2.32)
Weighted-average number of shares used in computing basic net loss per common share	65,594,792	62,312,418	65,220,518	62,207,328
Weighted-average number of shares used in computing diluted net loss per common share	65,594,792	62,312,418	65,220,518	62,207,328

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2020	$ 416,157	$ 62	$ 1,402,262	$ 302	$ (986,469)
Beginning Balance, Shares at Dec. 31, 2020		61,898,090
Issuance of common stock upon exercise of stock options	1,110		1,110
Issuance of common stock upon exercise of stock options, Shares		47,763
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes	(1,897)		(1,897)
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes, Shares		229,087
Issuance of common stock pursuant to ESPP purchases	2,558		2,558
Issuance of common stock pursuant to ESPP purchases, Shares		65,110
Stock-based compensation	20,378		20,378
Other comprehensive income	(181)			(181)
Net loss	(74,930)				(74,930)
Ending Balance at Mar. 31, 2021	363,195	$ 62	1,424,411	121	(1,061,399)
Ending Balance, Shares at Mar. 31, 2021		62,240,050
Beginning Balance at Dec. 31, 2020	416,157	$ 62	1,402,262	302	(986,469)
Beginning Balance, Shares at Dec. 31, 2020		61,898,090
Other comprehensive income	0
Net loss	(144,522)
Ending Balance at Jun. 30, 2021	315,766	$ 62	1,446,393	302	(1,130,991)
Ending Balance, Shares at Jun. 30, 2021		62,379,118
Beginning Balance at Mar. 31, 2021	363,195	$ 62	1,424,411	121	(1,061,399)
Beginning Balance, Shares at Mar. 31, 2021		62,240,050
Issuance of common stock upon exercise of stock options	403		403
Issuance of common stock upon exercise of stock options, Shares		28,575
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes	(65)		(65)
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes, Shares		110,493
Stock-based compensation	21,644		21,644
Other comprehensive income	181			181
Net loss	(69,592)				(69,592)
Ending Balance at Jun. 30, 2021	315,766	$ 62	1,446,393	302	(1,130,991)
Ending Balance, Shares at Jun. 30, 2021		62,379,118
Beginning Balance at Dec. 31, 2021	196,410	$ 65	1,485,805	100	(1,289,560)
Beginning Balance, Shares at Dec. 31, 2021		64,636,641
Issuance of common stock upon exercise of stock options	324		324
Issuance of common stock upon exercise of stock options, Shares		21,653
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes	(981)		(981)
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes, Shares		308,118
Issuance of common stock pursuant to ESPP purchases	2,259		2,259
Issuance of common stock pursuant to ESPP purchases, Shares		89,050
Stock-based compensation	19,475		19,475
Other comprehensive income	(2,062)			(2,062)
Net loss	(81,423)				(81,423)
Ending Balance at Mar. 31, 2022	134,002	$ 65	1,506,882	(1,962)	(1,370,983)
Ending Balance, Shares at Mar. 31, 2022		65,055,462
Beginning Balance at Dec. 31, 2021	$ 196,410	$ 65	1,485,805	100	(1,289,560)
Beginning Balance, Shares at Dec. 31, 2021		64,636,641
Issuance of common stock upon exercise of stock options, Shares	36,668
Stock Issued During Period, Shares, New Issues	2,065,358
Other comprehensive income	$ (4,072)
Net loss	(163,893)
Ending Balance at Jun. 30, 2022	118,360	$ 67	1,575,719	(3,973)	(1,453,453)
Ending Balance, Shares at Jun. 30, 2022		67,272,761
Beginning Balance at Mar. 31, 2022	134,002	$ 65	1,506,882	(1,962)	(1,370,983)
Beginning Balance, Shares at Mar. 31, 2022		65,055,462
Issuance of common stock upon exercise of stock options	216		216
Issuance of common stock upon exercise of stock options, Shares		15,015
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes	(114)		(114)
Issuance of common stock upon vesting of restricted share units, net of shares withheld for employee taxes, Shares		136,916
Stock Issued During Period, Shares, New Issues		2,065,368
Stock Issued During Period, Value, New Issues	48,495	$ 2	48,493
Stock-based compensation	20,242		20,242
Other comprehensive income	(2,011)			(2,011)
Net loss	(82,470)				(82,470)
Ending Balance at Jun. 30, 2022	$ 118,360	$ 67	$ 1,575,719	$ (3,973)	$ (1,453,453)
Ending Balance, Shares at Jun. 30, 2022		67,272,761

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (82,470)	$ (81,423)	$ (69,592)	$ (74,930)	$ (163,893)	$ (144,522)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization					3,052	2,908
Amortization (accretion) of premium (discount) on marketable securities					88	112
Non-cash interest expense					1,541	476
Amortization of operating lease right-of-use assets					1,518	1,301
Stock-based compensation					38,984	41,184
Changes in operating assets and liabilities:
Accounts receivables					(965)	(2,044)
Inventories					(6,806)	(6,841)
Prepaid expenses and other assets, current					2,977	(7,121)
Other assets, non-current					(394)	0
Accounts payable					(6,844)	(9,730)
Accrued liabilities					13,971	7,683
Accrued compensation					(2,525)	(4,655)
Operating lease liabilities					(2,735)	(2,328)
Other liabilities, noncurrent					5,870	0
Net cash used in operating activities					(116,161)	(123,577)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment					(636)	(1,920)
Purchases of marketable securities					(386,025)	0
Maturities of marketable securities					29,500	47,670
Net cash provided by (used in) investing activities					(357,161)	45,750
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock in settlement of employee stock purchase plan and exercise of stock options					2,799	4,083
Proceeds from issuance of common stock upon at-the-market offering, net of issuance cost					48,495	0
Taxes paid related to net share settlement of equity awards					(1,095)	(1,962)
Payments of debt issuance costs					0	(49)
Net cash provided by financing activities					50,199	2,072
Effect of exchange rate changes on cash and cash equivalents					(446)	259
Net decrease in cash, cash equivalents and restricted cash					(423,569)	(75,496)
Cash, cash equivalents and restricted cash at beginning of period		$ 687,153		$ 497,202	687,153	497,202	$ 497,202
Cash, cash equivalents and restricted cash at end of period	263,584		421,706		263,584	421,706	687,153
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid for interest					14,511	6,788
Cash paid for income taxes					80	0
SUPPLEMENTAL DISCLOSURES OF NON-CASH INVESTING AND FINANCING INFORMATION:
Accrued issuance costs					0	(26)
Accrued purchase of property and equipment					7	(36)
RECONCILIATION OF CASH, CASH EQUIVALENTS, AND RESTRICTED CASH TO THE CONDENSED CONSOLIDATED BALANCE SHEETS
Cash and cash equivalents	261,152		419,311		261,152	419,311	$ 684,717
Restricted cash	2,432		2,395		2,432	2,395
Total cash and cash equivalents and restricted cash	$ 263,584		$ 421,706		$ 263,584	$ 421,706

Organization

Organization	6 Months Ended
	Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	1. Organization Global Blood Therapeutics, Inc., or the Company, we, us or our, was incorporated in Delaware in February 2011 and commenced operations in May 2012. We are a biopharmaceutical company dedicated to the discovery, development and delivery of life-changing treatments that provide hope to underserved patient communities, starting with sickle cell disease, or SCD. In November 2019, we received U.S. Food and Drug Administration, or FDA, accelerated approval for our first medicine, Oxbryta ® (voxelotor) tablets for the treatment of SCD in adults and children 12 years of age and older, and we began to make Oxbryta available to patients through our specialty pharmacy partner network in December 2019. We have since received additional regulatory approvals of Oxbryta in and outside of the United States, including the accelerated approval we received from the FDA in December 2021 to expand Oxbryta’s indication for the treatment of SCD to children ages 4 to less than 12 years. In addition, in February 2022, we received Marketing Authorization from the European Commission for the use of Oxbryta for the treatment of hemolytic anemia (which is low hemoglobin due to red blood cell destruction) due to SCD in adult and pediatric patients 12 years of age and older as monotherapy or in combination with hydroxycarbamide (hydroxyurea). Our principal operations are based in South San Francisco, California. Liquidity We have incurred significant operating losses since inception and have cumulative net losses of $ 1.453 billion . Our ultimate success depends on the outcome of our commercialization of Oxbryta and research and development activities. We expect to incur additional losses for the foreseeable future to commercialize Oxbryta and conduct product research and development. If needed, we intend to raise additional capital through borrowings, the issuance of additional equity, and potentially through strategic alliances with partner companies or other transactions. However, if such financing is not available at adequate levels, we will need to re-evaluate our operating plans. We believe that our existing cash and cash equivalents and investments of $ 664.0 million as of June 30, 2022 will be sufficient to fund our cash requirements for at least twelve months subsequent to the issuance of these financial statements.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2022
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	2. Summary of Significant Accounting Policies Basis of Preparation and Presentation of Financial Information The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or SEC, regarding interim financial 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 balance sheet as of December 31, 2021, has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as our annual consolidated 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 our financial information. The results of operations for the six months ended June 30, 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 unaudited interim condensed consolidated financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2021 , included in the Annual Report on Form 10-K we filed with the SEC on February 23, 2022. Use of Estimates The preparation of the accompanying unaudited interim condensed consolidated financial statements in accordance with U.S. GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of variable consideration and costs and expenses during the reporting period. We base our estimates and assumptions on historical experience when available and on various factors that we believe to be reasonable under the circumstances. We evaluate our estimates and assumptions on an ongoing basis. Our actual results could differ from these estimates under different assumptions or conditions. Concentration of Risk Credit Risk We invest in a variety of financial instruments and, by our Board approved investment policy, limit the amount of credit exposure with any one issuer, industry or geographic area for investments other than instruments backed by the U.S. federal government. Major Customers We have entered into agreements with certain limited specialty pharmacies and specialty distributors for the distribution of Oxbryta in the United States. For the six months ended June 30, 2022 , our three largest customers represented approximately 98 % of our product revenue and approximately 97 % of our accounts receivable balance at June 30, 2022. Major Suppliers We do not currently have any of our own manufacturing facilities, and, therefore, depend on an outsourced manufacturing strategy for the production of Oxbryta for commercial use and for the production of Oxbryta and our product candidates for clinical trials. We have contracts in place with third-party manufacturers that are approved for the commercial production of Oxbryta and third-party suppliers that are approved for Oxbryta’s active pharmaceutical ingredient. Although there are potential sources of supply other than our existing manufacturers and suppliers, any new supplier would be required to qualify under applicable regulatory requirements. Principles of Consolidation The accompanying unaudited interim condensed consolidated financial statements include the accounts of the Company and our wholly owned subsidiaries. All intercompany transactions and balances have been eliminated upon consolidation. Significant Accounting Policies Except as noted below, there have been no material revisions in our significant accounting policies described in Note 2 to the consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2021 . Stock-Based Compensation We measure and recognize stock-based compensation expense, including employee and non-employee equity awards, based on fair value at the grant date. We use the Black-Scholes-Merton option-pricing model to calculate grant date fair value. For performance-based awards that do not include market-based conditions, we record share-based compensation expense only when the performance-based award is deemed probable of achievement. We utilize both quantitative and qualitative criteria to judge whether the awards are probable of achievement. For awards with market-based performance conditions, we use a Monte-Carlo simulation model to estimate grant date fair value and we recognize the share-based compensation expense of the award over the derived service period regardless of whether the underlying performance condition is met. Stock-based compensation expense recognized in the consolidated statements of operations is based on stock awards ultimately vested, taking into consideration actual forfeitures. Accounting Pronouncement Issued But Not Yet Adopted In March 2020, Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, ASU, No. 2020-04, Reference Rate Reform (Topic 848). The guidance contains practical expedients for reference rate reform related activities that impact debt, leases, derivatives, and other contracts. The guidance in ASU 2020-04 is optional and may be elected over time as reference rate reform activities occur. We continue to evaluate the impact of the guidance and may apply the elections as applicable as changes occur.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value Measurements	3. Fair Value Measurements Fair value accounting is applied for all financial assets and liabilities that are recognized or disclosed at fair value in the interim condensed consolidated financial statements on a recurring basis (at least annually). Our financial instruments consist of cash and cash equivalents, marketable securities, accounts receivables, accounts payable, accrued liabilities, convertible debt and long-term debt. Long-term debt and convertible debt are reported at amortized cost on our interim condensed consolidated balance sheets. Cash and cash equivalents, marketable securities and restricted cash are reported at their respective fair values on our interim condensed consolidated balance sheets. The remaining financial instruments are reported on our interim condensed consolidated balance sheets at cost that approximate current fair values due to their relatively short maturities. Assets and liabilities recorded at fair value on a recurring basis in the interim condensed consolidated balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. In accordance with ASC 820-10, Fair Value Measurements and Disclosures, we determine the fair value of financial and non-financial assets liabilities using the three-tier fair value hierarchy for disclosure of fair value measurements as follows: Level 1 – Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2 – Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and Level 3 – Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data. The following table summarizes our financial assets measured at fair value on a recurring basis (in thousands): June 30, 2022 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 224,325 $ 224,325 $ — $ — Corporate debt securities 63,362 — 63,362 — U.S. government agency securities 49,124 — 49,124 — Certificates of deposits 1,942 — 1,942 — U.S. government securities 192,485 — 192,485 — U.S. treasury bills 100,956 5,000 95,956 — Total financial assets $ 632,194 $ 229,325 $ 402,869 $ — December 31, 2021 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 671,845 $ 671,845 $ — $ — Corporate debt securities 10,006 — 10,006 — U.S. government agency securities 4,843 — 4,843 — Certificates of deposits 244 — 244 — U.S. government securities 34,964 — 34,964 — Total financial assets $ 721,902 $ 671,845 $ 50,057 $ — We estimate the fair values of our investments in corporate debt securities, government and government related securities and certificates of deposits by taking into consideration valuations obtained from third-party pricing services. The fair value of our marketable securities classified within Level 2 is based upon observable inputs that may include benchmark yields, reported trades, broker/dealer quotes, issuer spreads, two-sided markets, benchmark securities, bids, offers and reference data including market research publications. At June 30, 2022, and December 31, 2021, the weighted average remaining contractual maturities of our Level 2 investments were 15 months and 18 months, respectively, and all of these investments are rated A-1/P-1 or A/A2, or higher, by Moody’s and Standard & Poor’s. There were no transfers between Level 1 and Level 2 during the periods presented. There were no sales of available-for-sale securities except for money market funds in the periods presented. No credit loss allowance was recorded as of June 30, 2022 , as we do not believe the unrealized loss is a result of a credit loss due to the nature of our investments. We also considered the current and expected future economic and market conditions and determined that the estimate of credit losses was not significantly impacted.

Available-for-Sale Securities

Available-for-Sale Securities	6 Months Ended
	Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Available-for-Sale Securities	4. Available-for-Sale Securities Estimated fair values of available-for-sale securities are generally based on prices obtained from commercial pricing services. The following table is a summary of available-for-sale securities recorded in cash and cash equivalents, restricted cash, or marketable securities in our interim condensed consolidated balance sheets (in thousands): June 30, 2022 Amortized Unrealized Unrealized Estimated Fair Cost Gains (Losses) Value Financial Assets: Money market funds $ 224,325 $ — $ — $ 224,325 Corporate debt securities 64,089 2 ( 729 ) 63,362 U.S. government agency securities 49,891 4 ( 771 ) 49,124 Certificates of deposits 1,959 — ( 17 ) 1,942 U.S. government securities 194,572 39 ( 2,126 ) 192,485 U.S. treasury bills 101,202 — ( 246 ) 100,956 Total $ 636,038 $ 45 $ ( 3,889 ) $ 632,194 December 31, 2021 Amortized Unrealized Unrealized Estimated Fair Cost Gains (Losses) Value Financial Assets: Money market funds $ 671,845 $ — $ — $ 671,845 Corporate debt securities 10,037 — ( 31 ) 10,006 U.S. government agency securities 4,862 — ( 19 ) 4,843 Certificates of deposits 245 — ( 1 ) 244 U.S. government securities 35,133 — ( 169 ) 34,964 Total $ 722,122 $ — $ ( 220 ) $ 721,902 The following table summarizes the classification of the available-for-sale securities on our interim condensed consolidated balance sheets (in thousands): June 30, 2022 December 31, 2021 Cash and cash equivalents $ 229,325 $ 671,845 Short-term marketable securities 256,006 — Long-term marketable securities 146,863 50,057 Total $ 632,194 $ 721,902 We do not intend to sell the investments that are in an unrealized loss position, and it is unlikely that we will be required to sell the investments before recovery of their amortized cost basis, which may be maturity. We have determined that the gross unrealized losses on our marketable securities at June 30, 2022 , were temporary in nature.

Balance Sheet Components

Balance Sheet Components	6 Months Ended
	Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Balance Sheet Components	5. Balance Sheet Components Inventories Inventories consist of the following (in thousands): June 30, 2022 December 31, 2021 Raw materials $ 5,425 $ 10,616 Work-in-process $ 57,753 45,662 Finished goods $ 2,638 1,924 Total inventories $ 65,816 $ 58,202 We have capitalized $ 400,000 and $ 408,000 of stock-based compensation expense to our inventories for the three months ended June 30, 2022, and 2021, respectively; and $ 733,000 and $ 838,000 for the six months ended June 30, 2022 and 2021, respectively. The depreciation expense capitalized into inventories are not material for the three- and six-months ended June 30, 2022 and 2021. See Note 9—Stock-based Compensation for details on stock-based compensation expenses recognized during the three- and six-months ended June 30, 2022, and 2021. Property and Equipment Property and equipment consists of the following (in thousands): June 30, 2022 December 31, 2021 Laboratory equipment $ 15,041 $ 14,373 Computer equipment 2,850 2,841 Leasehold improvements 32,281 32,281 Construction-in-progress 257 934 Total property and equipment 50,429 50,429 Less: accumulated depreciation and amortization ( 18,004 ) ( 15,511 ) Property and equipment, net $ 32,425 $ 34,918 Accrued liabilities Accrued liabilities consist of the following (in thousands): June 30, 2022 December 31, 2021 Accrued research and development costs $ 11,184 $ 8,525 Accrued manufacturing costs 13,599 11,327 Accrued professional and consulting services 12,134 7,863 Accrued sales deductions 14,956 10,205 Other 1,393 1,377 Total accrued liabilities $ 53,266 $ 39,297 Other liabilities, current Other liabilities consist of the following (in thousands): June 30, 2022 December 31, 2021 Operating lease liabilities, current $ 6,119 $ 5,670 Other current liabilities $ 260 222 Total other liabilities, current $ 6,379 $ 5,892

Long-term Debt

Long-term Debt	6 Months Ended
	Jun. 30, 2022
Disclosure Text Block [Abstract]
Long-term Debt	6. Long-term Debt Amended and Restated Loan Agreement In December 2019, we entered into a term loan agreement, or 2019 Term Loan, with funds managed by Pharmakon Advisors LP, which are BioPharma Credit PLC, as collateral agent, Biopharma Credit Investments V (Master) LP, as a lender, and BPCR Limited Partnership, as a lender, and collectively with Biopharma Credit Investments V (Master) LP, the Lenders, for a senior secured credit facility consisting of an initial term loan of $ 75.0 million, with an option to draw an additional $ 75.0 million until December 31, 2020. The first tranche of $ 75.0 million was funded in December 2019 and the second tranche of $ 75.0 million was funded in November 2020. In December 2021, we entered into an amended and restated loan agreement, or A&R Term Loan, which superseded in its entirety the 2019 Term Loan, and provided us with an additional term loan commitment from the Lenders in the aggregate principal amount of $ 100.0 million, or which we refer to as the Tranche C Loan. Further, the A&R Term Loan extended the maturity date and interest payments for the previous tranches under the 2019 Term Loan to conform with the new Tranche C Loan. The maturity date of the A&R Term Loan was extended to December 17, 2027 , with interest-only payments extended to March 31, 2025. The Term Loan bears interest at a floating per annum interest rate equal to 7.00 % plus the greater of (a) the 3-month LIBOR rate and (b) 2 %. Interest on amounts outstanding are payable quarterly in arrears. The obligations under the A&R Term Loan are secured by a first priority security interest in and a lien on substantially all of our assets, subject to certain exceptions. The Tranche C Loan was funded in December 2021. In the event we default, the interest rate would be 3 % above the rate that is otherwise applicable thereto. Interest on amounts outstanding are payable quarterly in arrears. We have the option to prepay all or a portion of the borrowed amounts under the A&R Term Loan. If we exercise this option, we must pay a prepayment fee between 1 % and 3 % of the principal amount being prepaid, or Prepayment Fee, depending on the timing of the prepayment. If the prepayment occurs before December 2024, we must also pay an amount equal to the sum of all interest that would have accrued and been payable from date of prepayment through December 2026, or Make Whole Amount. We are obligated to pay an additional fee to the Lenders determined by multiplying the principal amount being paid or prepaid multiplied by 2 %, or Paydown Fee, when such payments are made. In the event of default or change in control, all unpaid principal and all accrued and unpaid interest amounts (if any) become immediately due and payable, at which point, we will be subject to the Prepayment Fee, the Make Whole Amount (if any) and the Paydown Fee. Events of default include, but are not limited to, a payment default, a material adverse change and insolvency. Using the net present value method, we concluded the amendment and restatement of the 2019 Term Loan should be accounted for as a debt modification as the present value of the remaining cash flows of the A&R Term Loan are not substantially different from the present value of the remaining cash flows of the 2019 Term Loan. As the amendment was accounted for as a debt modification, no gain or loss was recognized. Debt issuance costs associated with the Tranche C Loan paid directly to the Lenders of $ 3.4 million were treated as discounts on the A&R Term Loan and the other debt issuance costs of $ 0.1 million were expensed as incurred. The debt discounts associated with the Tranche C Loan, the remaining unamortized debt discounts associated with the 2019 Term Loan as of the debt amendment date, and the Paydown Fee are being amortized or accreted to interest expenses throughout the remaining life of the A&R Term Loan using the effective interest rate method. As of June 30, 2022 , there were unamortized issuance costs and debt discounts of $ 4.4 million, which were recorded as a direct deduction from the A&R Term Loan on the consolidated balance sheet. Future payments of principal and interest on the A&R Term Loan as of June 30, 2022 (in thousands): 2022 (six months) $ 11,250 2023 22,500 2024 22,500 2025 104,688 2026 97,188 2027 89,688 Total minimum payments 347,814 Less: amount representing interest ( 92,814 ) Less: amount representing Paydown Fee ( 5,000 ) Long-term debt, gross 250,000 Discount on notes payable ( 4,419 ) Accretion of Paydown Fee 1,549 Long-term debt $ 247,130

Convertible Debt

Convertible Debt	6 Months Ended
	Jun. 30, 2022
Convertible Debt [Abstract]
Convertible Debt	7. Convertible Debt Convertible Notes In December 2021, we issued in a private placement an aggregate principal amount of $ 345.0 million of 1.875 % convertible senior notes due 2028, or 2028 Notes. The aggregate principal amount on the 2028 Notes sold reflects the full exercise by the initial purchasers of their option to purchase an additional $ 45.0 million in aggregate principal amount of the 2028 Notes. We received total proceeds, net of debt issuance and offering costs of $ 11.0 million, of $ 334.0 million from the offering. We used $ 46.8 million of the net proceeds to pay the costs of the capped call transactions described below. The 2028 Notes are senior unsecured obligations and accrue interest at a rate of 1.875 % per annum payable semiannually in arrears on June 15 and December 15 of each year, beginning on June 15, 2022. The 2028 Notes mature on December 15, 2028 , unless converted, redeemed or repurchased in accordance with their terms prior to such date. The 2028 Notes are convertible into cash, shares of our common stock or a combination of cash and shares of our common stock, at our election, on or after December 20, 2027 and prior to the 31st scheduled trading day immediately preceding the maturity date, at an initial conversion rate of 31.4985 shares of our common stock per $ 1,000 principal amount of the 2028 Notes, which is equivalent to an initial conversion price of approximately $ 31.75 per share of our common stock. The 2028 Notes are convertible at the option of the holders prior to the close of business on the second scheduled trading day immediately preceding the maturity date. We may redeem for cash all or any portion of the 2028 Notes, at our option, on or after December 20, 2027 and prior to the 31st scheduled trading day immediately preceding the maturity date, if the last reported sale price of our common stock has been at least 130 % of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period (including the last trading day of such period) ending on the trading day immediately preceding the date on which we provide notice of redemption, at a redemption price equal to 100 % of the principal amount of the 2028 Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. If we elect to redeem fewer than all the outstanding notes, at least $ 100.0 million aggregate principal amount of notes must be outstanding and not subject to redemption as of, and after giving effect to, delivery of the relevant notice of redemption. We have elected to irrevocably fix the settlement method to physical settlement in the indenture governing the 2028 Notes. No “sinking fund” is provided for the 2028 Notes, which means that we are not required to redeem or retire the 2028 Notes periodically. If we undergo a fundamental change (as set forth in the indenture governing the 2028 Notes), noteholders may require us to repurchase for cash all or any portion of their 2028 Notes at a repurchase price equal to 100% of the principal amount of the 2028 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. As a result of adopting ASU 2020-06, Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging - Contracts in Entity’s Own Equity (Subtopic 815-40), we accounted for the 2028 Notes as a single liability. As of June 30, 2022 , the 2028 Notes were recorded at the aggregate principal amount of $ 345.0 million less unamortized issuance costs of $ 10.2 million as a long-term liability on the consolidated balance sheets. The debt issuance costs are amortized to interest expense over the contractual term of the 2028 Notes at an effective interest rate of 2.37 %. The following table presents the components of interest expense related to 2028 Notes (in thousands): Three months ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Stated coupon interest $ 1,617 $ — $ 3,234 $ — Amortization of debt issuance cost 364 — 726 — Total interest expense $ 1,981 $ — $ 3,960 $ — As of June 30, 2022, the fair value of the 2028 Notes was $40 7.2 million . The fair value was estimated using a third-party valuation model based on observable inputs and is considered Level 2 in the fair value hierarchy. Capped Calls In connection with the issuance of the 2028 Notes, we entered into capped call transactions with certain of the initial purchasers of the 2028 Notes and other financial institutions, totaling $ 46.8 million, which we refer to as the Capped Calls. The Capped Calls cover, subject to customary adjustments, the number of shares of our common stock that initially underlie the 2028 Notes (or 10,866,983 shares of our common stock). The Capped Calls have an initial strike price and an initial cap price of $ 31.7475 per share and $ 49.80 per share, respectively, subject to certain adjustments. Conditions that cause adjustments to the initial strike price of the Capped Calls mirror conditions that result in corresponding adjustments to the conversion price of the 2028 Notes. The Capped Calls are expected to offset the potential dilution to our common stock as a result of any conversion of the 2028 Notes, subject to a cap based on the cap price. We considered the Capped Calls as separate financial instruments and not part of the 2028 Notes. We recorded the cost of the Capped Calls, totaling $ 46.8 million, as a reduction to additional paid-in capital for the year ended December 31, 2021.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies Leases We have operating leases for our headquarters in South San Francisco, where we have office and research and development laboratory facilities and equipment. Our leases have remaining lease terms of 1 to 10 years. Most of these leases require monthly lease payments that may be subject to annual increases throughout the lease term. Certain of these leases include renewal options at our election, with renewal terms that can extend the lease term from 1 to 10 years. These optional periods have not been considered in the determination of the right-of-use assets, or ROU assets, or lease liabilities associated with these leases as we did not consider it reasonably certain that we would exercise the options. Lease costs included in operating expense in the interim condensed consolidated statement of operations and comprehensive loss in relation to these operating leases were $ 2.4 million and $ 2.4 million for the three months ended June 30, 2022, and 2021, respectively and $ 4.9 million and $ 5.6 million for the six months ended June 30, 2022 and 2021, respectively. Included in these lease costs were variable lease costs, which were not included within the measurement of our operating ROU assets and operating lease liabilities in the amount of $ 1.0 million and $ 1.2 million for the three months ended June 30, 2022, and 2021, respectively; and $ 2.0 million and $ 2.0 million for the six months ended June 30, 2022 and 2021, respectively. The variable lease cost is comprised primarily of our cost in certain research and development arrangements that contain embedded equipment, and our proportionate share of operating expenses, property taxes, and insurance in relation with our facility lease. These costs are classified as operating lease expense due to our election to not separate lease and non-lease components. Supplemental information related to leases for the periods reported is as follows (in thousands, except weighted-average remaining lease term and weighted-average discount rate): Six Months Ended June 30, 2022 2021 Cash paid for amounts included in the measurement of lease liabilities $ 6,073 $ 5,883 Weighted-average remaining lease term of operating leases (in years) 7.8 8.7 Weighted-average discount rate of operating leases 8.7 % 8.7 % The majority of our lease costs are driven by our operating lease for our headquarters, where we have office and research and development laboratory space. In March 2017, we entered into a noncancelable operating lease for our headquarters, or Original Lease, for approximately 67,185 square feet of space in South San Francisco, California, or the Prior Premises. The Original Lease term commenced in November 2017 when we gained control over physical access to the Prior Premises for a 10-year period. In August 2018, we entered into an amendment to the Original Lease, or Lease Amendment, to relocate our headquarters from the Prior Premises to a then to-be-constructed building consisting of approximately 164,150 rentable square feet of space in South San Francisco, California, or the Substitute Premises, when the Substitute Premises were ready for occupancy, or Substitute Premises Payment Commencement Date. The Lease Amendment has a contractual term, or Substitute Premises Term, of 10 years from the Substitute Premises Payment Commencement Date. The Lease Amendment grants us an option to extend the Lease Amendment for an additional 10 -year period. Future minimum rental payments under the Lease Amendment during the 10 -year term are $ 121.5 million in the aggregate. Under the Lease Amendment, we are obligated to pay to the landlord certain costs, including taxes and operating expenses. The Lease Amendment also provides a tenant inducement allowance of up to $ 27.9 million, of which $ 4.1 million was repaid to the landlord in the form of additional monthly rent with interest applied. As of June 30, 2022, we have capitalized $ 32.3 million within property and equipment, net for construction of leasehold improvements at the Substitute Premises, which were mostly acquired with the tenant inducement provided under the Lease Amendment. After relocating to the Substitute Premises, we surrendered and delivered the Prior Premises to the landlord in May 2020, upon which time we had no further obligations with respect to the Prior Premises other than with respect to the Initial Allowance, which we will repay to the landlord in the form of additional monthly rent with interest applied over the term of the Original Lease through November 2027. As of June 30, 2022, the maturities of our operating lease liabilities were as follows (in thousands): Year ending December 31, Amount 2022 (six months) 6,149 2023 12,584 2024 12,948 2025 13,368 2026 13,803 Thereafter 46,703 Total lease payments 105,555 Less: Imputed interest ( 29,114 ) Present value of operating lease liabilities $ 76,441 The operating leases require us to share in prorated operating expenses and property taxes based upon actual amounts incurred. These amounts are not fixed for future periods and, therefore, are not included in the future commitments listed above. Other commitments In the ordinary course of business, we enter into various firm purchase commitments related to research and development activities and manufacturing activities. As of June 30, 2022, we have noncancelable contractual obligations under the terms of a manufacturing agreement of approximately $ 1.3 million. Contingencies In the ordinary course of business, we may be subject to legal claims and regulatory actions that could have a material adverse effect on our business or financial position. We assess our potential liability in such situations by analyzing potential outcomes, assuming various litigation, regulatory and settlement strategies. If we determine a loss is probable and its amount can be reasonably estimated, we accrue an amount equal to the estimated loss. No losses and no provision for a loss contingency have been recorded to date.

Stockholder's Equity

Stockholder's Equity	6 Months Ended
	Jun. 30, 2022
Stockholders' Equity Note [Abstract]
Stockholder's Equity	9. Stockholder's Equity In August 2020, we entered into an at-the-market offering program, or “ATM”, which provides for the offering, issuance and sale by us of shares of our common stock from time to time for aggregate gross proceeds of up to $ 200.0 million. In the six months ended June 30, 2022, we have sold and issued 2,065,358 shares of common stock pursuant to the ATM, with total gross proceeds of $ 50.0 million before deducting underwriting discounts, commissions, and other offering expenses payable by us of $ 1.5 million.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2022
Share-Based Payment Arrangement [Abstract]
Stock-Based Compensation	10. Stock-Based Compensation We have three stock-based compensation plans – the Amended and Restated 2017 Inducement Equity Plan, or the 2017 Inducement Plan, the Amended and Restated 2015 Stock Option and Incentive Plan, or 2015 Plan, and the 2012 Stock Option and Grant Plan, or 2012 Plan. As of June 30, 2022 , there were 2,329,397 shares reserved under the 2017 Inducement Plan and 5,396,563 shares reserved under the 2015 Plan for the future issuance of equity awards. Upon adoption of the 2015 Plan in July 2015, no new awards or grants are permitted under the 2012 Plan. See Note 11 to the Consolidated Financial Statements included in our Annual Report on Form 10-K for the year ended December 31, 2021, for additional information related to these stock-based compensation plans. Stock Options The following summarizes stock option activity under the 2017 Inducement Plan, 2015 Plan and 2012 Plan: Number of Options Weighted-Average Exercise Price Outstanding—December 31, 2021 3,553,763 $ 42.0 0 Options granted 671,701 29.32 Options exercised ( 36,668 ) 14.73 Options canceled ( 150,247 ) 50.13 Outstanding—June 30, 2022 4,038,549 $ 39.84 The fair values of stock options granted to employees were calculated using the following assumptions: Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Expected term (in years) 5.3 5.3 - 6.1 5.3 - 6.1 5.3 - 6.1 Volatility 65.50 % 68.1 %- 72.2 % 65.5 %- 70.5 % 68.1 %- 72.7 % Risk-free interest rate 3.6 % 1.0 %- 1.1 % 1.4 %- 3.6 % 0.9 %- 1.1 % Dividend yield — — — — Restricted Stock Units The following table summarizes activity of restricted stock units, or RSUs, granted to employees with service-based vesting under the 2017 Inducement Plan and 2015 Plan and related information: Weighted- Average Number Grant Date of RSUs Fair Value Non-vested units — December 31, 2021 2,986,269 $ 45.37 RSUs granted 1,886,774 29.83 RSUs vested ( 482,023 ) 51.13 RSUs forfeited ( 300,044 ) 40.03 Non-vested units — June 30, 2022 4,090,976 $ 37.92 Performance-based RSU Awards 2020 Market-Condition RSU Awards Beginning in June 2020, the Compensation Committee of our Board of Directors has granted awards of performance-based RSUs to certain of our senior management, including our executive officers, under the 2015 Plan, the vesting of which is contingent upon the achievement of three escalating stock price targets, which we refer to as the 2020 Market-Condition RSU Awards. Since June 1, 2020, certain awards have been forfeited in connection with employee terminations and new awards have been granted in connection with new appointments, with awards for up to an aggregate of 450,800 RSUs outstanding as of June 30, 2022 . Upon the achievement of the respective stock price targets, 50% of the RSUs allotted to that tranche will vest, while the remaining 50% will vest on the first anniversary of the date the stock price target was achieved, subject to the employee’s continued employment or other service relationship with us through such vesting date. Under the terms of the awards, if the stock price targets are not achieved for all or some of the tranches on or before June 30, 2024, the unvested awards will be automatically terminated and forfeited. The compensation cost for the RSUs with a market condition is not reversed when the market condition is not satisfied. The target prices and vesting tranches are set forth in the following table: Stock Price Targets Number of Units Allowed $ 109.20 90,160 $ 145.60 157,780 $ 182.00 202,860 The grant date fair value of the 2020 Market-Condition RSU Awards was estimated using a Monte Carlo simulation model, which includes variables such as the expected volatility of our share price and interest rates to generate potential future outcomes. We recognize the related compensation expense on a straight-line basis over the applicable derived service periods, which are the estimated periods of time that would be required to satisfy the market conditions. The following table summarizes the 2020 Market-Condition RSU Awards granted and forfeited during the six months ended June 30, 2022: Weighted- Weighted- Average Average Remaining Aggregate Number Grant Date Vesting Intrinsic of RSUs Fair Value Period (years) Value Non-vested market-condition awards — December 31, 2021 450,800 $ 43.17 0.30 $ 13,195 Granted — — — Vested — — — Forfeited — — — Non-vested market condition awards — June 30, 2022 450,800 $ 43.15 0.21 $ 14,403 At June 30, 2022 , total unrecognized compensation expense related to non-vested 2020 Market-Condition RSU Awards was $ 1.6 million, which is expected to be recognized over their respective remaining derived service periods. The weighted average remaining derived service period is 0.21 years. For the three and six months ended June 30, 2022 , and 2021, we recognized $ 0.9 million, $ 2.0 million, $ 1.5 million, and $ 4.6 million, respectively, in stock-based compensation expense related to the 2020 Market-Condition RSU Awards. Total Shareholder Return and Patient Share RSU Awards In March 2022, the Compensation Committee of our Board of Directors granted two types of performance-based RSU awards to our executive officers under the 2015 Plan that are milestone based, with 50 % of the awards earned based on relative total stockholder return, or TSR (which we refer to as the TSR RSU Awards), and 50 % of the awards earned based on patient market share (which we refer to as the Patient Share RSU Awards). Each of these awards are measured over a three-year performance period beginning on January 1, 2022. TSR RSU awards The vesting of the TSR RSU Awards is contingent upon our TSR percentile ranking relative to the companies within the NASDAQ Biotechnology Index over the three-year cumulative performance period of January 1, 2022 through December 31, 2024. Vesting is also subject to continued service requirements through the date that the Compensation Committee of our Board of Directors determines achievement of the applicable performance condition following the end of the performance period. The number of shares of common stock that could be distributed at the end of the three-year performance period may range from 0 % to 200 % of the target number of shares granted. The TSR percentile rankings and performance multipliers for the TSR RSU Awards are set forth in the following table: Total Shareholder Return Percentile Rank within the Performance Measurement Index Performance Multiplier if Total Shareholder Return is ≥ 0% Performance Multiplier if Total Shareholder Return is < 0% 100 th Percentile or higher 200 % 100 % 50 th Percentile 100 % 100 % 25 th Percentile 50 % 50 % Below 25 th Percentile 0 % 0 % The grant date fair value of the TSR RSU Awards was estimated using a Monte Carlo simulation model, which includes variables such as the expected volatility of our share price and interest rates to generate potential future outcomes. We recognize the related compensation expense on a straight-line basis over the applicable derived service periods, which are the estimated periods of time that would be required to satisfy the market conditions. The following table summarizes the TSR RSU Awards granted during the six months ended June 30, 2022: Weighted- Weighted- Average Average Remaining Aggregate Number Grant Date Vesting Intrinsic of RSUs Fair Value Period (years) Value Total Shareholder Return awards — December 31, 2021 — $ — — $ — Granted 98,276 47.34 2.59 Vested — — — Forfeited — — — Total Shareholder Return awards— June 30, 2022 98,276 $ 47.34 2.59 $ 3,140 The following table summarizes the assumptions used to estimate the fair value of the TSR RSU Awards as of the grant date: Six Months Ended June 30, 2022 Expected term (in years) 2.84 Volatility 66.01 % Risk-free interest rate 1.4 % Dividend yield — At June 30, 2022 , total unrecognized compensation expense related to TSR RSU Awards was $ 4.1 million, which is expected to be recognized over their respective remaining derived service periods. The weighted average remaining derived service period is 2.59 years. For the three and six months ended June 30, 2022 , we recognized $ 0.4 million and $ 0.5 million in stock-based compensation expense related to the TSR RSU Awards. Patient Share RSU Awards The vesting of the Patient Share RSU Awards is contingent upon our percentage of patient share within a comparator group consisting of all U.S.-based SCD patients (including pediatric patients) during a three-year cumulative performance period of January 1, 2022 through December 31, 2024. Vesting is also subject to continued service requirements through the date that the Compensation Committee of our Board of Directors determines achievement of the applicable performance condition following the end of the performance period. The number of shares of common stock that could be distributed at the end of the three-year performance period may range from 0 % to 200 % of the target number of shares granted. The patient share percentages and performance multipliers for the Patient Share RSU Awards are set forth in the following table: Patient Share Performance Multiplier 19.80% 200 % 18% 100 % 16.20% 50 % Below 16.2% 0 % The following table summarizes the Patient Share RSU Awards granted during the six months ended June 30, 2022: Weighted- Weighted- Average Average Remaining Aggregate Number Grant Date Vesting Intrinsic of RSUs Fair Value Period (years) Value Performance-based awards — December 31, 2021 — $ — — $ — Granted 98,277 29.87 2.59 Vested — — — Forfeited — — — Performance-based awards— June 30, 2022 98,277 $ 29.87 2.59 $ 3,140 Expense for these grants is based on the fair value on the date of the grant and will be recognized over the period from the date the performance condition is determined to be probable of occurring through the date the applicable condition is expected to be met. If the performance condition is not considered probable of being achieved, no stock-based compensation expense is recognized until such time as the performance condition is considered probable of being met, if at all. As of June 30, 2022, the performance conditions were not deemed probable of achievement, and as a result no stock compensation expense was recognized for these awards. The total unrecognized compensation expense related to unvested Patient Share RSU Awards was $ 2.9 million. Stock-Based Compensation Expense Total stock-based compensation recognized by function included in the condensed consolidated statements of operations and comprehensive loss was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Research and development $ 5,926 $ 4,906 $ 11,457 $ 10,216 Selling, general and administrative 13,917 15,064 27,527 30,134 Total stock-based compensation expense $ 19,843 $ 19,970 $ 38,984 $ 40,350

Related Parties Transaction

Related Parties Transaction	6 Months Ended
	Jun. 30, 2022
Related Party Transactions [Abstract]
Related Parties Transaction	11. Related Parties Transaction In the six months ended June 30, 2022, we donated $ 0.3 million to The GBT Foundation, a California nonprofit public benefit corporation we established in August 2021. The GBT Foundation is a related party affiliate as certain of our officers also serve, without additional compensation, as directors or officers of The GBT Foundation. The purpose of The GBT Foundation is to fund programs that will support people within the sickle cell disease community and beyond through education, empowerment, improved healthcare access and enhanced health equity.

Net Loss per Share

Net Loss per Share	6 Months Ended
	Jun. 30, 2022
Earnings Per Share [Abstract]
Net Loss per Share	12. Net Loss per Share Basic net loss per share is computed by dividing net loss by the weighted-average number of common shares outstanding for the period. Since we were in a loss position for all periods presented, diluted net loss per share is the same as basic net loss per share for all periods as the inclusion of all potential common shares outstanding would have been anti-dilutive. The following securities were not included in the diluted net loss per share calculations because their effect was anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Options to purchase common stock 4,038,549 3,739,404 4,038,549 3,739,404 Convertible Notes (as converted to common stock) 10,866,983 — 10,866,983 — Restricted stock units 4,738,329 3,352,273 4,738,329 3,352,273 Total 19,643,861 7,091,677 19,643,861 7,091,677

Subsequent Event

Subsequent Event	6 Months Ended
	Jun. 30, 2022
Subsequent Events [Abstract]
Subsequent Event	13. Subsequent Events In July 2022, the Medicines and Healthcare products Regulatory Agency (MHRA) granted Great Britain marketing authorization for Oxbryta for the treatment of hemolytic anemia due to SCD in adult and pediatric patients 12 years of age and older as monotherapy or in combination with hydroxyurea. On August 7, 2022, we entered into an Agreement and Plan of Merger, or Merger Agreement, with Pfizer Inc., a Delaware corporation, or Pfizer, and Ribeye Acquisition Corp., a Delaware corporation and a wholly owned subsidiary of Pfizer, or Merger Sub, pursuant to which, and upon the terms and subject to the conditions described therein, Merger Sub will merge with and into the Company, with the Company surviving the merger as a wholly owned subsidiary of Pfizer, which we refer to as the Merger. Under the Merger Agreement, at the closing of the Merger, each issued and outstanding share of our common stock (other than shares owned by the Company, any subsidiary of the Company, Pfizer, Merger Sub or any other subsidiary of Pfizer and other than stockholders of the Company who have validly exercised their statutory rights of appraisal under the DGCL) will be converted into the right to receive $ 68.50 per share, net to the seller in cash, without interest and subject to any required withholding of taxes. The Merger is expected to close as early as the fourth quarter of 2022 . If the Merger Agreement is terminated under specified circumstances, we will be required to pay Pfizer a termination fee of $ 217 million. The Merger Agreement also provides that, in connection with the termination of the Merger Agreement under specified antitrust related circumstances, Pfizer will be required to pay us a “reverse termination fee” of $ 326 million.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2022
Accounting Policies [Abstract]
Basis of Preparation and Presentation of Financial Information	Basis of Preparation and Presentation of Financial Information The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or SEC, regarding interim financial 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 balance sheet as of December 31, 2021, has been derived from audited consolidated financial statements at that date but does not include all of the information required by U.S. GAAP for complete financial statements. These unaudited interim condensed consolidated financial statements have been prepared on the same basis as our annual consolidated 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 our financial information. The results of operations for the six months ended June 30, 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 unaudited interim condensed consolidated financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2021 , included in the Annual Report on Form 10-K we filed with the SEC on February 23, 2022.
Use of Estimates	Use of Estimates The preparation of the accompanying unaudited interim condensed consolidated financial statements in accordance with U.S. GAAP requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of variable consideration and costs and expenses during the reporting period. We base our estimates and assumptions on historical experience when available and on various factors that we believe to be reasonable under the circumstances. We evaluate our estimates and assumptions on an ongoing basis. Our actual results could differ from these estimates under different assumptions or conditions.
Concentration of Risk	Concentration of Risk Credit Risk We invest in a variety of financial instruments and, by our Board approved investment policy, limit the amount of credit exposure with any one issuer, industry or geographic area for investments other than instruments backed by the U.S. federal government. Major Customers We have entered into agreements with certain limited specialty pharmacies and specialty distributors for the distribution of Oxbryta in the United States. For the six months ended June 30, 2022 , our three largest customers represented approximately 98 % of our product revenue and approximately 97 % of our accounts receivable balance at June 30, 2022. Major Suppliers We do not currently have any of our own manufacturing facilities, and, therefore, depend on an outsourced manufacturing strategy for the production of Oxbryta for commercial use and for the production of Oxbryta and our product candidates for clinical trials. We have contracts in place with third-party manufacturers that are approved for the commercial production of Oxbryta and third-party suppliers that are approved for Oxbryta’s active pharmaceutical ingredient. Although there are potential sources of supply other than our existing manufacturers and suppliers, any new supplier would be required to qualify under applicable regulatory requirements.
Principles of Consolidation	Principles of Consolidation The accompanying unaudited interim condensed consolidated financial statements include the accounts of the Company and our wholly owned subsidiaries. All intercompany transactions and balances have been eliminated upon consolidation.
Significant Accounting Policies	Significant Accounting Policies Except as noted below, there have been no material revisions in our significant accounting policies described in Note 2 to the consolidated financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2021 .
Stock-based Compensation	Stock-Based Compensation We measure and recognize stock-based compensation expense, including employee and non-employee equity awards, based on fair value at the grant date. We use the Black-Scholes-Merton option-pricing model to calculate grant date fair value. For performance-based awards that do not include market-based conditions, we record share-based compensation expense only when the performance-based award is deemed probable of achievement. We utilize both quantitative and qualitative criteria to judge whether the awards are probable of achievement. For awards with market-based performance conditions, we use a Monte-Carlo simulation model to estimate grant date fair value and we recognize the share-based compensation expense of the award over the derived service period regardless of whether the underlying performance condition is met. Stock-based compensation expense recognized in the consolidated statements of operations is based on stock awards ultimately vested, taking into consideration actual forfeitures.
Accounting Pronouncement Issued But Not Yet Adopted	Accounting Pronouncement Issued But Not Yet Adopted In March 2020, Financial Accounting Standards Board, or FASB, issued Accounting Standards Update, ASU, No. 2020-04, Reference Rate Reform (Topic 848). The guidance contains practical expedients for reference rate reform related activities that impact debt, leases, derivatives, and other contracts. The guidance in ASU 2020-04 is optional and may be elected over time as reference rate reform activities occur. We continue to evaluate the impact of the guidance and may apply the elections as applicable as changes occur.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2022
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured on Recurring Basis	The following table summarizes our financial assets measured at fair value on a recurring basis (in thousands): June 30, 2022 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 224,325 $ 224,325 $ — $ — Corporate debt securities 63,362 — 63,362 — U.S. government agency securities 49,124 — 49,124 — Certificates of deposits 1,942 — 1,942 — U.S. government securities 192,485 — 192,485 — U.S. treasury bills 100,956 5,000 95,956 — Total financial assets $ 632,194 $ 229,325 $ 402,869 $ — December 31, 2021 Total Level 1 Level 2 Level 3 Financial Assets: Money market funds $ 671,845 $ 671,845 $ — $ — Corporate debt securities 10,006 — 10,006 — U.S. government agency securities 4,843 — 4,843 — Certificates of deposits 244 — 244 — U.S. government securities 34,964 — 34,964 — Total financial assets $ 721,902 $ 671,845 $ 50,057 $ —

Available-for-Sale Securities (

Available-for-Sale Securities (Tables)	6 Months Ended
	Jun. 30, 2022
Investments, Debt and Equity Securities [Abstract]
Summary of Available-for-Sale Securities	The following table is a summary of available-for-sale securities recorded in cash and cash equivalents, restricted cash, or marketable securities in our interim condensed consolidated balance sheets (in thousands): June 30, 2022 Amortized Unrealized Unrealized Estimated Fair Cost Gains (Losses) Value Financial Assets: Money market funds $ 224,325 $ — $ — $ 224,325 Corporate debt securities 64,089 2 ( 729 ) 63,362 U.S. government agency securities 49,891 4 ( 771 ) 49,124 Certificates of deposits 1,959 — ( 17 ) 1,942 U.S. government securities 194,572 39 ( 2,126 ) 192,485 U.S. treasury bills 101,202 — ( 246 ) 100,956 Total $ 636,038 $ 45 $ ( 3,889 ) $ 632,194 December 31, 2021 Amortized Unrealized Unrealized Estimated Fair Cost Gains (Losses) Value Financial Assets: Money market funds $ 671,845 $ — $ — $ 671,845 Corporate debt securities 10,037 — ( 31 ) 10,006 U.S. government agency securities 4,862 — ( 19 ) 4,843 Certificates of deposits 245 — ( 1 ) 244 U.S. government securities 35,133 — ( 169 ) 34,964 Total $ 722,122 $ — $ ( 220 ) $ 721,902
Summary of Classification of Available-for-Sale Securities on Consolidated Balance Sheets	The following table summarizes the classification of the available-for-sale securities on our interim condensed consolidated balance sheets (in thousands): June 30, 2022 December 31, 2021 Cash and cash equivalents $ 229,325 $ 671,845 Short-term marketable securities 256,006 — Long-term marketable securities 146,863 50,057 Total $ 632,194 $ 721,902

Balance Sheet Components (Table

Balance Sheet Components (Tables)	6 Months Ended
	Jun. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Inventories	Inventories consist of the following (in thousands): June 30, 2022 December 31, 2021 Raw materials $ 5,425 $ 10,616 Work-in-process $ 57,753 45,662 Finished goods $ 2,638 1,924 Total inventories $ 65,816 $ 58,202
Property and Equipment	Property and equipment consists of the following (in thousands): June 30, 2022 December 31, 2021 Laboratory equipment $ 15,041 $ 14,373 Computer equipment 2,850 2,841 Leasehold improvements 32,281 32,281 Construction-in-progress 257 934 Total property and equipment 50,429 50,429 Less: accumulated depreciation and amortization ( 18,004 ) ( 15,511 ) Property and equipment, net $ 32,425 $ 34,918
Accrued Liabilities	Accrued liabilities consist of the following (in thousands): June 30, 2022 December 31, 2021 Accrued research and development costs $ 11,184 $ 8,525 Accrued manufacturing costs 13,599 11,327 Accrued professional and consulting services 12,134 7,863 Accrued sales deductions 14,956 10,205 Other 1,393 1,377 Total accrued liabilities $ 53,266 $ 39,297
Other Liabilities, current	Other liabilities consist of the following (in thousands): June 30, 2022 December 31, 2021 Operating lease liabilities, current $ 6,119 $ 5,670 Other current liabilities $ 260 222 Total other liabilities, current $ 6,379 $ 5,892

Long-term Debt (Tables)

Long-term Debt (Tables)	6 Months Ended
	Jun. 30, 2022
Text Block [Abstract]
Schedule of Future payments of principal and interest on the Term Loan	Future payments of principal and interest on the A&R Term Loan as of June 30, 2022 (in thousands): 2022 (six months) $ 11,250 2023 22,500 2024 22,500 2025 104,688 2026 97,188 2027 89,688 Total minimum payments 347,814 Less: amount representing interest ( 92,814 ) Less: amount representing Paydown Fee ( 5,000 ) Long-term debt, gross 250,000 Discount on notes payable ( 4,419 ) Accretion of Paydown Fee 1,549 Long-term debt $ 247,130

Convertible Debt (Tables)

Convertible Debt (Tables)	6 Months Ended
	Jun. 30, 2022
Convertible Debt [Abstract]
Schedule of debt interest expense	The following table presents the components of interest expense related to 2028 Notes (in thousands): Three months ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Stated coupon interest $ 1,617 $ — $ 3,234 $ — Amortization of debt issuance cost 364 — 726 — Total interest expense $ 1,981 $ — $ 3,960 $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Summary of supplemental information related to leases	Supplemental information related to leases for the periods reported is as follows (in thousands, except weighted-average remaining lease term and weighted-average discount rate): Six Months Ended June 30, 2022 2021 Cash paid for amounts included in the measurement of lease liabilities $ 6,073 $ 5,883 Weighted-average remaining lease term of operating leases (in years) 7.8 8.7 Weighted-average discount rate of operating leases 8.7 % 8.7 %
Schedule of Lessee, Operating Lease, Liability, Maturity	As of June 30, 2022, the maturities of our operating lease liabilities were as follows (in thousands): Year ending December 31, Amount 2022 (six months) 6,149 2023 12,584 2024 12,948 2025 13,368 2026 13,803 Thereafter 46,703 Total lease payments 105,555 Less: Imputed interest ( 29,114 ) Present value of operating lease liabilities $ 76,441

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2022
Stock Option Activity	The following summarizes stock option activity under the 2017 Inducement Plan, 2015 Plan and 2012 Plan: Number of Options Weighted-Average Exercise Price Outstanding—December 31, 2021 3,553,763 $ 42.0 0 Options granted 671,701 29.32 Options exercised ( 36,668 ) 14.73 Options canceled ( 150,247 ) 50.13 Outstanding—June 30, 2022 4,038,549 $ 39.84
Valuation Assumptions for Stock Awards	The fair values of stock options granted to employees were calculated using the following assumptions: Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Expected term (in years) 5.3 5.3 - 6.1 5.3 - 6.1 5.3 - 6.1 Volatility 65.50 % 68.1 %- 72.2 % 65.5 %- 70.5 % 68.1 %- 72.7 % Risk-free interest rate 3.6 % 1.0 %- 1.1 % 1.4 %- 3.6 % 0.9 %- 1.1 % Dividend yield — — — —
Non-Vested Restricted Stock Activity	The following table summarizes activity of restricted stock units, or RSUs, granted to employees with service-based vesting under the 2017 Inducement Plan and 2015 Plan and related information: Weighted- Average Number Grant Date of RSUs Fair Value Non-vested units — December 31, 2021 2,986,269 $ 45.37 RSUs granted 1,886,774 29.83 RSUs vested ( 482,023 ) 51.13 RSUs forfeited ( 300,044 ) 40.03 Non-vested units — June 30, 2022 4,090,976 $ 37.92
Summary of Activity of Market-Condition Awards	The compensation cost for the RSUs with a market condition is not reversed when the market condition is not satisfied. The target prices and vesting tranches are set forth in the following table: Stock Price Targets Number of Units Allowed $ 109.20 90,160 $ 145.60 157,780 $ 182.00 202,860
Valuation Assumptions of Total Shareholder Return RSU Awards	The following table summarizes the 2020 Market-Condition RSU Awards granted and forfeited during the six months ended June 30, 2022: Weighted- Weighted- Average Average Remaining Aggregate Number Grant Date Vesting Intrinsic of RSUs Fair Value Period (years) Value Non-vested market-condition awards — December 31, 2021 450,800 $ 43.17 0.30 $ 13,195 Granted — — — Vested — — — Forfeited — — — Non-vested market condition awards — June 30, 2022 450,800 $ 43.15 0.21 $ 14,403
Stock-based Compensation Expense Recognized	Total stock-based compensation recognized by function included in the condensed consolidated statements of operations and comprehensive loss was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Research and development $ 5,926 $ 4,906 $ 11,457 $ 10,216 Selling, general and administrative 13,917 15,064 27,527 30,134 Total stock-based compensation expense $ 19,843 $ 19,970 $ 38,984 $ 40,350
Schedule of Market - Based Share Awards	The TSR percentile rankings and performance multipliers for the TSR RSU Awards are set forth in the following table: Total Shareholder Return Percentile Rank within the Performance Measurement Index Performance Multiplier if Total Shareholder Return is ≥ 0% Performance Multiplier if Total Shareholder Return is < 0% 100 th Percentile or higher 200 % 100 % 50 th Percentile 100 % 100 % 25 th Percentile 50 % 50 % Below 25 th Percentile 0 % 0 %
Summary of the TSR RSU Awards Granted	The following table summarizes the TSR RSU Awards granted during the six months ended June 30, 2022: Weighted- Weighted- Average Average Remaining Aggregate Number Grant Date Vesting Intrinsic of RSUs Fair Value Period (years) Value Total Shareholder Return awards — December 31, 2021 — $ — — $ — Granted 98,276 47.34 2.59 Vested — — — Forfeited — — — Total Shareholder Return awards— June 30, 2022 98,276 $ 47.34 2.59 $ 3,140
Schedule of Performance Based RSU Awards Granted	The following table summarizes the Patient Share RSU Awards granted during the six months ended June 30, 2022: Weighted- Weighted- Average Average Remaining Aggregate Number Grant Date Vesting Intrinsic of RSUs Fair Value Period (years) Value Performance-based awards — December 31, 2021 — $ — — $ — Granted 98,277 29.87 2.59 Vested — — — Forfeited — — — Performance-based awards— June 30, 2022 98,277 $ 29.87 2.59 $ 3,140
Summary of Assumptions used to Estimate the Fair Value of the TSR RSU Awards	The following table summarizes the assumptions used to estimate the fair value of the TSR RSU Awards as of the grant date: Six Months Ended June 30, 2022 Expected term (in years) 2.84 Volatility 66.01 % Risk-free interest rate 1.4 % Dividend yield —
Schedule of Patient Share Percentage And Performance Multiplier	The patient share percentages and performance multipliers for the Patient Share RSU Awards are set forth in the following table: Patient Share Performance Multiplier 19.80% 200 % 18% 100 % 16.20% 50 % Below 16.2% 0 %

Net Loss per Share (Tables)

Net Loss per Share (Tables)	6 Months Ended
	Jun. 30, 2022
Earnings Per Share [Abstract]
Potentially Dilutive Securities that were Not Included in Diluted Net Loss per Share Calculations	The following securities were not included in the diluted net loss per share calculations because their effect was anti-dilutive: Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Options to purchase common stock 4,038,549 3,739,404 4,038,549 3,739,404 Convertible Notes (as converted to common stock) 10,866,983 — 10,866,983 — Restricted stock units 4,738,329 3,352,273 4,738,329 3,352,273 Total 19,643,861 7,091,677 19,643,861 7,091,677

Organization and Basis of Prese

Organization and Basis of Presentation - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Class of Stock [Line Items]
Cumulative net losses	$ (1,453,453)	$ (1,289,560)
Cash and cash equivalents and investments	$ 664,000

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) - Customer Concentration Risk [Member] - Two Major Customers [Member]	6 Months Ended
	Jun. 30, 2022
Revenue, Product and Service Benchmark [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	98%
Accounts Receivable [Member]
Summary Of Significant Accounting Policies [Line Items]
Concentration risk percentage	97%

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Assets Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	$ 632,194	$ 721,902
Level 1 [Member] | U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0
Corporate Debt Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0
U.S. Government Agency Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0
Certificates of Deposits [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0
Fair Value Measurements, Recurring [Member] | U.S. treasury bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	100,956
Fair Value Measurements, Recurring [Member] | U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	192,485	34,964
Fair Value Measurements, Recurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	229,325	671,845
Fair Value Measurements, Recurring [Member] | Level 1 [Member] | U.S. treasury bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	5,000
Fair Value Measurements, Recurring [Member] | Level 1 [Member] | U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value		0
Fair Value Measurements, Recurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	402,869	50,057
Fair Value Measurements, Recurring [Member] | Level 2 [Member] | U.S. treasury bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	95,956
Fair Value Measurements, Recurring [Member] | Level 2 [Member] | U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	192,485	34,964
Fair Value Measurements, Recurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0	0
Fair Value Measurements, Recurring [Member] | Level 3 [Member] | U.S. treasury bills
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0
Fair Value Measurements, Recurring [Member] | Level 3 [Member] | U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0	0
Fair Value Measurements, Recurring [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	224,325	671,845
Fair Value Measurements, Recurring [Member] | Money Market Funds [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	224,325	671,845
Fair Value Measurements, Recurring [Member] | Money Market Funds [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0	0
Fair Value Measurements, Recurring [Member] | Money Market Funds [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0	0
Fair Value Measurements, Recurring [Member] | Corporate Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	63,362	10,006
Fair Value Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value		0
Fair Value Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	63,362	10,006
Fair Value Measurements, Recurring [Member] | Corporate Debt Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0	0
Fair Value Measurements, Recurring [Member] | U.S. Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	49,124	4,843
Fair Value Measurements, Recurring [Member] | U.S. Government Agency Securities [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value		0
Fair Value Measurements, Recurring [Member] | U.S. Government Agency Securities [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	49,124	4,843
Fair Value Measurements, Recurring [Member] | U.S. Government Agency Securities [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	0	0
Fair Value Measurements, Recurring [Member] | Certificates of Deposits [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	1,942	244
Fair Value Measurements, Recurring [Member] | Certificates of Deposits [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value		0
Fair Value Measurements, Recurring [Member] | Certificates of Deposits [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	1,942	244
Fair Value Measurements, Recurring [Member] | Certificates of Deposits [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets, fair value	$ 0	$ 0

Available-for-Sale Securities -

Available-for-Sale Securities - Summary of Available-for-Sale Securities (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	$ 636,038	$ 722,122
Available for sale securities, Unrealized Gains	45	0
Available for sale securities, Unrealized (Losses)	(3,889)	(220)
Available for sale securities, Estimated Fair Value	632,194	721,902
US Treasury Bill Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	101,202
Available for sale securities, Unrealized Gains	0
Available for sale securities, Unrealized (Losses)	(246)
Available for sale securities, Estimated Fair Value	100,956
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	64,089	10,037
Available for sale securities, Unrealized Gains	2	0
Available for sale securities, Unrealized (Losses)	(729)	(31)
Available for sale securities, Estimated Fair Value	63,362	10,006
U.S. Government Agency Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	49,891	4,862
Available for sale securities, Unrealized Gains	4	0
Available for sale securities, Unrealized (Losses)	(771)	(19)
Available for sale securities, Estimated Fair Value	49,124	4,843
Money Market Funds [Member]
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	224,325	671,845
Available for sale securities, Unrealized Gains	0	0
Available for sale securities, Unrealized (Losses)	0
Available for sale securities, Estimated Fair Value	224,325	671,845
Certificates of Deposits [Member]
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	1,959	245
Available for sale securities, Unrealized Gains	0	0
Available for sale securities, Unrealized (Losses)	(17)	(1)
Available for sale securities, Estimated Fair Value	1,942	244
U.S. Government Securities [Member]
Debt Securities, Available-for-Sale [Line Items]
Available for sale securities, Amortized Cost	194,572	35,133
Available for sale securities, Unrealized Gains	39	0
Available for sale securities, Unrealized (Losses)	(2,126)	(169)
Available for sale securities, Estimated Fair Value	$ 192,485	$ 34,964

Available-for-Sale Securities_2

Available-for-Sale Securities - Summary of Classification of Available-for-Sale Securities on Consolidated Balance Sheets (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Investments, Debt and Equity Securities [Abstract]
Cash and cash equivalents	$ 229,325	$ 671,845
Short-term marketable securities	256,006	0
Long-term marketable securities	146,863	50,057
Total	$ 632,194	$ 721,902

Balance Sheet Components - Inve

Balance Sheet Components - Inventories (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Balance Sheet Components [Abstract]
Raw materials	$ 5,425	$ 10,616
Work-in-process	57,753	45,662
Finished goods	2,638	1,924
Total inventories	$ 65,816	$ 58,202

Balance Sheet Components - Prop

Balance Sheet Components - Property and Equipment (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 50,429	$ 50,429
Less: accumulated depreciation and amortization	(18,004)	(15,511)
Property and equipment, net	32,425	34,918
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	15,041	14,373
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	2,850	2,841
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	32,281	32,281
Construction-in-Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 257	$ 934

Balance Sheet Components - Addi

Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Balance Sheet Components [Abstract]
Share based compensation expense capitalized	$ 400,000	$ 408,000	$ 733,000	$ 838,000

Balance Sheet Components - Accr

Balance Sheet Components - Accrued Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Balance Sheet Components [Abstract]
Accrued research and development costs	$ 11,184	$ 8,525
Accrued manufacturing costs	13,599	11,327
Accrued professional and consulting services	12,134	7,863
Accrued sales deductions	14,956	10,205
Other	1,393	1,377
Total accrued liabilities	$ 53,266	$ 39,297

Balance Sheet Components - Othe

Balance Sheet Components - Other Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Balance Sheet Components [Abstract]
Operating lease liabilities, current	$ 6,119	$ 5,670
Other current liabilities	260	222
Total other liabilities, current	$ 6,379	$ 5,892

Long-term Debt - Additional Inf

Long-term Debt - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Nov. 30, 2020	Dec. 31, 2019
Long term debt	$ 247,130		$ 246,352
Debt issuance costs paid	0	$ 49
Term Loan
Debt maximum borrowing capacity	$ 100,000
Debt Instrument, Maturity Date	Dec. 17, 2027
Debt Instrument, Basis Spread on Variable Rate	7%
Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate	2%
Debt Instrument Additional Interest Rate On Debt Default	3%
Debt additional paydown fee	2%
Debt issuance costs paid	$ 3,400
Other debt issuance cost paid	100
Unamortized issuance costs and debt discounts	$ 4,400
Term Loan | Maximum
Debt prepayment fee	3%
Term Loan | Minimum
Debt prepayment fee	1%
Secured Debt
Debt maximum borrowing capacity	$ 75,000
Debt additional borrowing capacity	$ 75,000
Long term debt				$ 75,000	$ 75,000

Long-term Debt-Schedule of Futu

Long-term Debt-Schedule of Future payments of principal and interest on the Term Loan (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Contractual Obligation, Fiscal Year Maturity Schedule [Abstract]
2022 (nine months)	$ 11,250
2023	22,500
2024	22,500
2025	104,688
2026	97,188
2027	89,688
Total minimum payments	347,814
Less amount representing interest	(92,814)
Less amount representing Paydown Fee	(5,000)
Long-term debt, gross	250,000
Discount on notes payable	(4,419)
Accretion of Paydown Fee	1,549
Long-term debt, net	$ 247,130	$ 246,352

Convertible Debt (Additional In

Convertible Debt (Additional Information) (Details)	6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) Days $ / shares	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) $ / shares
Debt Instrument [Line Items]
Debt instrument principal amount	$ 345,000,000
Payments Of Debt Issuance Costs	0	$ 49,000
Unamortized debt issuance costs	10,200,000
Long-term debt, gross	$ 250,000,000
One Point Eight Seven Five Percent Convertible Senior Notes Due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	2.37%
Debt instrument, fair value	$ 7,200,000
Convertible Debt [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	1.875%		1.875%
Convertible Debt [Member] | One Point Eight Seven Five Percent Convertible Senior Notes Due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument principal amount			$ 345,000,000
Payments Of Debt Issuance Costs			11,000,000
Proceeds from convertible debt			334,000
Capped calls transactions	$ 46,800,000		$ 46,800,000
Maturity date			Dec. 15, 2028
Debt instrument convertible conversion ratio			31.4985
Debt instrument repurchase amount	$ 1,000,000
Debt instrument, convertible, conversion price | $ / shares			$ 31.75
Debt instrument, convertible, threshold percentage of stock price trigger	130%
Debt instrument, convertible, threshold trading days | Days	20
Debt instrument, convertible, threshold consecutive trading days | Days	30
Debt instrument, redemption price, percentage of principal amount redeemed			100%
Derivative cap price per share | $ / shares	$ 31.7475
Number of shares of common stock underlying notes | Days	10,866,983
Convertible Debt [Member] | One Point Eight Seven Five Percent Convertible Senior Notes Due 2028 [Member] | Call Option [Member]
Debt Instrument [Line Items]
Debt instrument principal amount			$ 45,000,000
Share price | $ / shares	$ 49.80
Non Convertible Debt [Member]
Debt Instrument [Line Items]
Debt instrument principal amount	$ 100,000,000

Convertible Debt - Schedule of

Convertible Debt - Schedule of debt interest expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Short-Term Debt [Line Items]
Total interest expense			$ 92,814
2.37% Convertible Senior Notes [Member]
Short-Term Debt [Line Items]
Stated coupon interest	$ 1,617	$ 0	3,234
Amortization of debt issuance costs	364	0	726
Total interest expense	$ 1,981	$ 0	$ 3,960

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	1 Months Ended		3 Months Ended		6 Months Ended
	Aug. 31, 2018 USD ($) ft²	Mar. 31, 2017 ft²	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)
Commitment And Contingencies [Line Items]
Facility size | ft²	164,150	67,185
Initial term		10 years
Future minimum rental payments under the Lease term			$ 121,500,000		$ 121,500,000
Operating lease term	10 years				10 years
Operating Lease Lease Expiration Period	10 years				10 years
Repayment of tenant inducement allowance	$ 4,100,000
Loss Contingency, Loss in Period					$ 0
Loss Contingency Accrual, Provision					0
Operating Lease Cost			2,400,000	$ 2,400,000	4,900,000	$ 5,600,000
variable lease cost			1,000	$ 1,200,000	$ 2,000,000	$ 2,000,000
Maximum [Member]
Commitment And Contingencies [Line Items]
Operating lease remaining lease term					10 years
Minimum [Member]
Commitment And Contingencies [Line Items]
Operating lease remaining lease term					1 year
Leasehold Improvements [Member]
Commitment And Contingencies [Line Items]
Property palnt and equipment additions					$ 32,300,000
Lease Agreements [Member] | Maximum [Member]
Commitment And Contingencies [Line Items]
Tenant inducement	$ 27,900,000
Manufacturing Agreement [Member]
Commitment And Contingencies [Line Items]
Noncancelable contractual obligations			$ 1,300,000		$ 1,300,000

Commitments and Contingencies_2

Commitments and Contingencies - Supplemental cash flow information (Detail) - Accounting Standards Update 2016-02 [Member] - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Commitment And Contingencies [Line Items]
Cash paid for amounts included in the measurement of lease liabilities	$ 6,073	$ 5,883
Weighted-average remaining lease term of operating leases (in years)	7 years 9 months 18 days	8 years 8 months 12 days
Weighted-average discount rate of operating leases	8.70%	8.70%

Commitments and Contingencies_3

Commitments and Contingencies - Lessee Operating Lease Liability Maturity (Detail) $ in Thousands	Jun. 30, 2022 USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2022 (six months)	$ 6,149
2023	12,584
2024	12,948
2025	13,368
2026	13,803
Thereafter	46,703
Total lease payments	105,555
Less: Imputed interest	(29,114)
Present value of operating lease liabilities	$ 76,441

Stockholder's Equity - Addition

Stockholder's Equity - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended		23 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022
Class of Stock [Line Items]
Proceeds from Issuance of Common Stock	$ 48,495	$ 0
Issuance of common stock upon at-the-market financing, Shares	2,065,358
Proceeds from issuance of common stock before offering expenses	$ 50,000		$ 50,000
Underwriting discounts, commissions, and other offering expenses payable	$ 1,500
Maximum [Member]
Class of Stock [Line Items]
Proceeds from Issuance of Common Stock			$ 200,000

Stock-Based Compensation - Plan

Stock-Based Compensation - Plan Summary - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation			$ 38,984	$ 41,184
Market Condition Awards Granted to Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 1,600		$ 1,600
Weighted average derived service period			2 months 15 days
Stock-based compensation	$ 900	$ 2,000	$ 1,500	$ 4,600
TSR RSU Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares Non-vested period	98,276		98,276		0
TSR RSU Awards [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			200%
TSR RSU Awards [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			0%
Patient Share RSU Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation			$ 2,900
Patient Share RSU Awards [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Granted Percentage			200%
Patient Share RSU Awards [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares Granted Percentage			0%
2017 Inducement Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance	2,329,397		2,329,397
2015 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for issuance	5,396,563		5,396,563
Percentage of patient market share			50%
2015 Plan [Member] | Market Condition Awards Granted to Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares Non-vested period	450,800		450,800		450,800
2015 Plan [Member] | TSR RSU Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 4,100		$ 4,100
Weighted average derived service period			2 years 7 months 2 days
Stock-based compensation	$ 400		$ 500
2015 Plan [Member] | Performance Based RSU Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares Non-vested period	450,800		450,800
Percentage of total stockholder return			50%
2015 Plan [Member] | Patient Share RSU Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares Non-vested period	98,277		98,277		0

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Detail)	6 Months Ended
	Jun. 30, 2022 $ / shares shares
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward]
Beginning balance, outstanding, Number of Options | shares	3,553,763
Options granted, Number of Options | shares	671,701
Options exercised, Number of Options | shares	(36,668)
Options canceled, Number of Options | shares	(150,247)
Ending balance, outstanding, Number of Options | shares	4,038,549
Weighted- Average Exercise Price
Beginning balance, Outstanding, Weighted-Average Exercise Price | $ / shares	$ 42
Options granted, Weighted-Average Exercise Price | $ / shares	29.32
Options exercised, Weighted-Average Exercise Price | $ / shares	14.73
Options canceled, Weighted-Average Exercise Price | $ / shares	50.13
Ending balance, Outstanding, Weighted-Average Exercise Price | $ / shares	$ 39.84

Stock-Based Compensation - Valu

Stock-Based Compensation - Valuation Assumptions for Stock Options Granted (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		5 years 3 months 18 days	5 years 3 months 18 days	5 years 3 months 18 days
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years 1 month 6 days	6 years 1 month 6 days	6 years 1 month 6 days
Employee Stock Option Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 18 days
Volatility	65.50%
Volatility, minimum		68.10%	65.50%	68.10%
Volatility, maximum		72.20%	70.50%	72.70%
Risk-free interest rate	3.60%
Risk-free interest rate, minimum		1%	1.40%	0.90%
Risk-free interest rate, maximum		1.10%	3.60%	1.10%
Dividend yield	0%	0%	0%	0%

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of RSU Activity Granted to Employees with Service-Based Vesting (Detail) - 2017 Inducement Plan and 2015 Plan [Member] - RSU [Member]	6 Months Ended
	Jun. 30, 2022 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Units, Beginning Balance | shares	2,986,269
RSUs granted, Number of RSUs | shares	1,886,774
RSUs vested, Number of RSUs | shares	(482,023)
RSUs forfeited, Number of RSUs | shares	(300,044)
Number of Units, Ending Balance | shares	4,090,976
Weighted-Average Grant Date Fair Value, Beginning Balance | $ / shares	$ 45.37
RSUs granted, Weighted-Average Grant Date Fair Value | $ / shares	29.83
RSUs vested, Weighted-Average Grant Date Fair Value | $ / shares	51.13
RSUs forfeited, Weighted-Average Grant Date Fair Value | $ / shares	40.03
Weighted-Average Grant Date Fair Value, Ending Balance | $ / shares	$ 37.92

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Share-based Compensation Arrangements by Share-based Payment Award (Detail) - 2020 Market Condition RSU Awards [Member]	Jun. 30, 2022 $ / shares shares
Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock Price Targets | $ / shares	$ 109.20
Number of Units Allowed | shares	90,160
Tranche Two [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock Price Targets | $ / shares	$ 145.60
Number of Units Allowed | shares	157,780
Tranche Three [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock Price Targets | $ / shares	$ 182
Number of Units Allowed | shares	202,860

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Activity Awards (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Market Condition Awards Granted to Employees [Member] | 2015 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Units, Beginning Balance	450,800
Number of Units granted	0
Number of Units vested	0
Number of Units forfeited	0
Number of Units, Ending Balance	450,800	450,800
Weighted-Average Grant Date Fair Value, Beginning Balance	$ 43.17
Weighted-Average Grant Date Fair Value granted	0
Weighted-Average Grant Date Fair Value vested	0
Weighted-Average Grant Date Fair Value forfeited	0
Weighted-Average Grant Date Fair Value, Ending Balance	$ 43.15	$ 43.17
Weighted-Average remaining vesting period (years), Beginning Balance	2 months 15 days	3 months 18 days
Weighted-Average remaining vesting period (years), Ending Balance	2 months 15 days	3 months 18 days
Non-vested units, Aggregate Intrinsic Value	$ 14,403	$ 13,195
TSR RSU Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Units, Beginning Balance	0
Number of Units granted	98,276
Number of Units vested	0
Number of Units forfeited	0
Number of Units, Ending Balance	98,276	0
Weighted-Average Grant Date Fair Value, Beginning Balance	$ 0
Weighted-Average Grant Date Fair Value granted	47.34
Weighted-Average Grant Date Fair Value vested	0
Weighted-Average Grant Date Fair Value forfeited	0
Weighted-Average Grant Date Fair Value, Ending Balance	$ 47.34	$ 0
Weighted-Average remaining vesting period (years), Beginning Balance	2 years 7 months 2 days
Non-vested units, Weighted-Average remaining vesting period (years) granted	2 years 7 months 2 days
Weighted-Average remaining vesting period (years), Ending Balance	2 years 7 months 2 days
Non-vested units, Aggregate Intrinsic Value	$ 3,140	$ 0
Performance-based RSU Awards [Member] | 2015 Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Units, Ending Balance	450,800

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Market-Based Share Awards (Detail) - TSR RSU Awards [Member]	6 Months Ended
	Jun. 30, 2022 shares
100th Percentile or Higher [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Performance Multiplier if Total Shareholder Return is Greater Than or Equal to 0%	200
Performance Multiplier if Total Shareholder Return is Less Than 0%	100
50th Percentile [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Performance Multiplier if Total Shareholder Return is Greater Than or Equal to 0%	100
Performance Multiplier if Total Shareholder Return is Less Than 0%	100
25th Percentile [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Performance Multiplier if Total Shareholder Return is Greater Than or Equal to 0%	50
Performance Multiplier if Total Shareholder Return is Less Than 0%	50
Below 25th Percentile [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Performance Multiplier if Total Shareholder Return is Greater Than or Equal to 0%	0
Performance Multiplier if Total Shareholder Return is Less Than 0%	0

Stock-Based Compensation - Su_4

Stock-Based Compensation - Summary of Assumptions used to Estimate the Fair Value of the TSR RSU Awards (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Total Shareholder Return RSU Awards [Member] | Two Thousand Fifteen Stock Option And Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)			2 years 10 months 2 days
Volatility			66.01%
Risk-free interest rate			1.40%
Dividend yield			0%
Employee Stock Option Member
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 18 days
Volatility	65.50%
Risk-free interest rate	3.60%
Dividend yield	0%	0%	0%	0%

Stock Based Compensation - Sche

Stock Based Compensation - Schedule of Patient Share Percentage And Performance Multiplier (Detail) - Patient Share RSU Awards	6 Months Ended
	Jun. 30, 2022
Patient Share 19.80%
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage Of Performance Multiplier	200%
Patient Share 18%
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage Of Performance Multiplier	100%
Patient Share 16.20%
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage Of Performance Multiplier	50%
Patient Share below 16.20%
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Percentage Of Performance Multiplier	0%

Stock-Based Compensation - Sc_2

Stock-Based Compensation - Schedule of Performance Based Awards (Details) - Two Thousand Fifteen Stock Option And Incentive Plan [Member] - $ / shares	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Dec. 31, 2021
Performance Based RSU Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Units, Ending Balance	450,800
Patient Share RSU Awards [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Number of Units, Beginning Balance	0
Number of Units granted	98,277
Number of Units vested	0
Number of Units forfeited	0
Number of Units, Ending Balance	98,277	0
Weighted-Average Grant Date Fair Value, Beginning Balance	$ 0
Weighted-Average Grant Date Fair Value granted	29.87
Weighted-Average Grant Date Fair Value vested	0
Weighted-Average Grant Date Fair Value forfeited	0
Weighted-Average Grant Date Fair Value, Ending Balance	$ 29.87	$ 0
Weighted-Average remaining vesting period (years), Beginning Balance	2 years 7 months 2 days
Weighted-Average remaining vesting period (years), granted	2 years 7 months 2 days
Weighted-Average remaining vesting period (years), Ending Balance	2 years 7 months 2 days
Aggregate Intrinsic Value, Beginning Balance,	$ 0
Aggregate Intrinsic Value, Ending Balance	$ 3,140	$ 0

Stock-Based Compensation - St_2

Stock-Based Compensation - Stock-Based Compensation Expense Recognized (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 19,843	$ 19,970	$ 38,984	$ 40,350
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	5,926	4,906	11,457	10,216
Selling, general and administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 13,917	$ 15,064	$ 27,527	$ 30,134

Related Parties Transaction (Ad

Related Parties Transaction (Additional Information) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2022 USD ($)
Related Party Transactions [Abstract]
Donations To Related Party	$ 0.3

Net Loss per Share - Potentiall

Net Loss per Share - Potentially Dilutive Securities that were Not Included in Diluted Net Loss per Share Calculations (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share	19,643,861	7,091,677	19,643,861	7,091,677
Employee Stock Option Member
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share	4,038,549	3,739,404	4,038,549	3,739,404
RSU [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share	4,738,329	3,352,273	4,738,329	3,352,273
Convertible Debt Securities [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from earnings per share	10,866,983	0	10,866,983	0

Subsequent Event - Additional I

Subsequent Event - Additional Information (Details) - Subsequent Event - Pfizer Inc Merger Agreement $ / shares in Units, $ in Millions	Aug. 07, 2022 USD ($) $ / shares
Subsequent Event [Line Items]
Termination fee	$ 217
Stock converted right to receive in cash consideration | $ / shares	$ 68.50
Reverse termination fee	$ 326