CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Cash flows from operating activities
Net loss	$ (58,769,000)	$ (190,418,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization		398,000
Non-cash lease expense	145,000	7,893,000
Non-cash gain on lease termination and remeasurement	(8,872,000)
Impairment costs	0	18,570,000
Accretion of short-term investment discounts	(1,251,000)	(3,698,000)
Stock-based compensation expense	26,347,000	40,779,000
Changes in operating assets and liabilities:
Interest receivable	206,000	(49,000)
Prepaid expenses and other current assets and prepaid expenses to related party	3,229,000	5,614,000
Other assets	122,000	(900,000)
Income tax payable		(128,000)
Accounts payable, accrued expenses, other liabilities and amount due to related party	(28,862,000)	(2,512,000)
Net cash used in operating activities	(67,705,000)	(124,451,000)
Cash flows from investing activities
Purchase of short-term investments		(125,827,000)
Maturities of short-term investments	95,000,000	163,812,000
Net cash provided by investing activities	95,000,000	37,985,000
Cash flows from financing activities
Proceeds from issuance of common stock in public offering, net of underwriting discounts, commissions and offering costs		70,169,000
Proceeds from issuance of stock under the 2020 Employee Stock Purchase Plan	21,000	326,000
Net cash provided by financing activities	21,000	70,495,000
Net increase (decrease) in cash, cash equivalents, and restricted cash	27,316,000	(15,971,000)
Cash, cash equivalents, and restricted cash at beginning of period	90,973,000	106,944,000
Cash, cash equivalents, and restricted cash at end of period	118,289,000	90,973,000
Non-cash investing and financing activities
Unrealized (loss) gain on available-for-sale securities	(73,000)	406,000
Reduction of right-of-use asset due to termination and remeasurement	(2,044,000)	(4,904,000)
Supplemental disclosure of cash flows
Income taxes paid, net of refunds		220,000
Cash and cash equivalents	118,289,000	90,121,000
Restricted cash	0	852,000
Total cash, cash equivalents, and restricted cash	$ 118,289,000	$ 90,973,000