Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Operating activities
Net loss	$ (65,504)	$ (38,514)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	8,246	3,188
Depreciation expense	606	353
Non-cash lease expense	154	111
Amortization of premiums and accretion of discounts on available-for-sale securities, net	(67)	347
Changes in operating assets and liabilities:
Unbilled grant receivable	636	(779)
Prepaid expenses and other current assets	(1,605)	5,152
Accounts payable and accrued liabilities	944	4,913
Operating lease liability	(212)	308
Net cash used in operating activities	(56,802)	(24,921)
Investing activities
Purchases of available-for-sale securities	(85,117)	(269,378)
Maturities of available-for-sale securities	119,274	226,420
Proceeds from sales of available-for-sale securities		18,052
Purchases of property and equipment	(1,140)	(546)
Net cash provided by (used in) investing activities	33,017	(25,452)
Financing activities
Proceeds from exercise of common stock options	507	314
Proceeds from public offering, net of issuance costs		96,762
Net cash provided by financing activities	507	97,076
Net (decrease) increase in cash, cash equivalents and restricted cash	(23,278)	46,703
Cash, cash equivalents and restricted cash, beginning of period	110,537	60,625
Cash, cash equivalents and restricted cash, end of period	$ 87,259	107,328
Supplemental disclosures of cash flow information:
Right-of-use asset obtained in exchange for new operating lease liability		$ 680