Fair Value Measurements (Tables)

6 Months Ended

Jun. 30, 2022

Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]

Financial Assets and Liabilities Measured at Fair Value on Recurring Basis

The following table presents information about our financial assets and liabilities that are measured at fair value on a recurring basis and indicates the fair value hierarchy of the valuation:

	June 30, 2022
	Total		Level 1		Level 2		Level 3
	(in thousands)
Assets
Cash equivalents:
Money market funds	$	99,569	$	99,569	$	—	$	—
Commercial paper		122,791		—		122,791		—
Agency discount notes		34,933		—		34,933		—
Total cash equivalents		257,293		99,569		157,724		—
Marketable securities:
U.S. treasury notes		75,976		—		75,976		—
Commercial paper		126,503		—		126,503		—
Corporate debt securities		15,987		—		15,987		—
Total marketable securities		218,466		—		218,466		—
Investment in equity securities		27,141		27,141		—		—
LianBio Warrant		751		751		—		—
Total financial assets	$	503,651	$	127,461	$	376,190	$	—
Liability
Embedded derivative	$	1,211	$	—	$	—	$	1,211

	December 31, 2021
	Total		Level 1		Level 2		Level 3
	(in thousands)
Assets
Cash equivalents:
Money market funds	$	176,115	$	176,115	$	—	$	—
Commercial paper		56,986		—		56,986		—
Total cash equivalents		233,101		176,115		56,986		—
Marketable securities:
U.S. treasury notes		76,472		—		76,472		—
Commercial paper		167,737		—		167,737		—
Corporate debt securities		122,490		—		122,490		—
Supranational debt securities		27,044		—		27,044		—
Total marketable securities		393,743		—		393,743		—
Investment in equity securities		49,148		49,148		—		—
LianBio Warrant		2,141		2,141		—		—
Total financial assets	$	678,133	$	227,404	$	450,729	$	—
Liability
Embedded derivative	$	1,171	$	—	$	—	$	1,171

Summary of Total Realized and Unrealized Gains and Losses Associated with Investment in Equity Securities

Total realized and unrealized gains and losses associated with investment in equity securities during the periods presented consisted of the following:

	Three Months Ended June 30,						Six Months Ended June 30,
	2022			2021			2022			2021
	(in thousands)
Net realized losses recognized on investment   in equity securities sold	$	(141	)	$	—		$	(1,385	)	$	—
Net unrealized losses recognized on investment   in equity securities held as of the end of the period		(10,221	)		(1,117	)		(21,843	)		(1,117	)
Total net losses included in “Other income   (expense), net”	$	(10,362	)	$	(1,117	)	$	(23,228	)	$	(1,117	)