Property and Equipment, net - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 8,113	$ 7,809
Less: Accumulated depreciation	(3,847)	(3,488)
Total property and equipment, net	4,266	4,321	[1]
Computer equipment and software
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	22	22
Laboratory equipment
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	6,921	6,540
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	947	947
Construction-in-progress
Property, Plant and Equipment [Line Items]
Total property and equipment, gross	$ 223	$ 300

[1] The condensed balance sheet as of December 31, 2020 has been derived from the audited financial statements as of that date.