Related Party Transactions - Additional Information (Details) - USD ($)		3 Months Ended		9 Months Ended
	May 05, 2020	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Commercial Supply Agreement
Related Party Transaction [Line Items]
Agreement extends period for termination	2 years
Minimum purchase obligation		$ 1,800,000		$ 1,800,000
Drug Product or Substance | Commercial Supply Agreement
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		400,000		400,000		$ 200,000
Expense related to services				400,000	$ 100,000
Takeda | Temporary Services Agreement
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		300,000		300,000		200,000
Frazier
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		0		0		35,000
Shared operating expenses		0	$ 62,000	16,000	100,000
PCI Pharma Services | Clinical Manufacturing Services
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		1,500,000		1,500,000		400,000
Expense related to services		600,000	900,000	2,200,000	1,500,000
Takeda | Takeda License
Related Party Transaction [Line Items]
Outstanding accounts payable and accrued expenses		22,000		22,000		$ 22,000
Expense related to services		$ 0	$ 0	$ 0	$ 0