Consolidated Statements of Operations and Comprehensive Loss - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Statement [Abstract]
Collaboration revenue	$ 40,497,000	$ 36,855,000	$ 26,581,000
Operating expenses:
Research and development expense:	73,020,000	148,269,000	173,385,000
General and administrative expense	40,813,000	59,543,000	56,963,000
Restructuring expenses	0	8,713,000	0
Total operating expenses	113,833,000	216,525,000	230,348,000
Other income (expense):
Interest income	8,436,000	12,073,000	2,883,000
Interest expense	(3,874,000)	(4,073,000)	(3,328,000)
Total other income (expense), net	4,562,000	8,000,000	(445,000)
Loss before income taxes	(68,774,000)	(171,670,000)	(204,212,000)
Income tax expense	(418,000)	0	0
Net loss	(69,192,000)	(171,670,000)	(204,212,000)
Other comprehensive loss:
Unrealized (loss) gain on marketable securities	(1,000)	163,000	(152,000)
Comprehensive loss	(69,193,000)	(171,507,000)	(204,364,000)
Net loss attributable to common stockholders - basic	(69,192,000)	(171,670,000)	(204,212,000)
Net loss attributable to common stockholders - diluted	$ (69,192,000)	$ (171,670,000)	$ (204,212,000)
Net loss per share attributable to common stockholders — basic (in dollars per share)	$ (0.56)	$ (1.48)	$ (2.18)
Net loss per share attributable to common stockholders — diluted (in dollars per share)	$ (0.56)	$ (1.48)	$ (2.18)
Weighted-average number of shares of common stock used in net loss per share attributable to common stockholders — basic (in shares)	122,539,598	116,112,891	93,654,243
Weighted-average number of shares of common stock used in net loss per share attributable to common stockholders — diluted (in shares)	122,539,598	116,112,891	93,654,243