Balance Sheet Details - Summary of Accrued Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accrued interest expense on deferred royalty obligation, current portion	$ 3,514	$ 3,567
Accrued royalties and in-license fees	2,445	685
Accrued manufacturing costs	1,306	627
Accrued professional fees	581	660
Accrued clinical costs	22	20
Accrued other	853	935
Total accrued expenses	$ 8,721	$ 6,494