Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 83,044	$ 30,360
Short-term investments	23,956	48,994
Accounts receivable	1,006	3,313
Prepaid and other current assets	8,514	6,843
Total current assets	116,520	89,510
Long-term investments		2,543
Other assets, noncurrent	528	528
Right-of-use assets	1,646	1,832
Property and equipment, net	382	433
Total assets	119,076	94,846
Current liabilities:
Accounts payable	2,956	5,931
Accrued compensation	2,232	2,476
Deferred revenue	1,332	1,983
Other accrued liabilities	6,983	6,743
Operating lease liability	678	663
Total current liabilities	14,181	17,796
Operating lease liability, noncurrent	806	981
Total liabilities	14,987	18,777
Commitments and Contingencies (Note 10)
Stockholders’ equity:
Preferred stock, $0.001 par value, 5,000,000 shares authorized; zero shares issued and outstanding
Common stock, $0.001 par value, 100,000,000 shares authorized; 31,331,027 and 22,097,820 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	31	22
Additional paid-in capital	441,252	390,803
Accumulated other comprehensive income	5	5
Accumulated deficit	(337,199)	(314,761)
Total stockholders’ equity	104,089	76,069
Total liabilities and stockholders’ equity	$ 119,076	$ 94,846