Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 95,057	$ 110,537
Short-term investments	157,347	143,222
Unbilled grant receivable		2,336
Prepaid expenses and other current assets	3,456	4,704
Total current assets	255,860	260,799
Restricted cash	210
Property and equipment, net	4,294	3,757
Operating lease right-of-use asset	1,648	1,460
Long-term investments	29,844	65,936
Other long-term assets	155	56
Total assets	292,011	332,008
Current liabilities:
Accounts payable	605	567
Accrued liabilities	8,780	8,437
Current operating lease liability	307	288
Total current liabilities	9,692	9,292
Operating lease liability, less current portion	1,754	1,632
Total liabilities	11,446	10,924
Stockholders' equity:
Common stock, $0.0001 par value; 900,000,000 shares authorized at June 30, 2022 and December 31, 2021, respectively; 37,817,724 and 37,379,077 shares issued and outstanding at June 30, 2022 and December 31,2021, respectively	4	4
Additional paid-in capital	423,696	417,363
Accumulated other comprehensive loss	(1,925)	(388)
Accumulated deficit	(141,210)	(95,895)
Total stockholders' equity	280,565	321,084
Total liabilities and stockholders' equity	$ 292,011	$ 332,008