Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
CURRENT ASSETS
Cash and cash equivalents	$ 14,637	$ 15,142
Marketable securities	52,088	77,986
License and development receivables	1,012	815
Prepaid expenses and other current assets	4,859	4,948
Total current assets	72,596	98,891
Restricted cash	1,828	1,838
Property and equipment, net	4,234	4,549
Operating lease right-of-use assets	3,712	3,806
Other non-current assets	800	842
TOTAL ASSETS	83,170	109,926
CURRENT LIABILITIES
Accounts payable	2,981	3,319
Operating lease liabilities	457	436
Deferred revenue	2,069	2,359
Accrued and other current liabilities	10,791	14,030
Total current liabilities	16,298	20,144
Non-current operating lease liabilities	4,467	4,608
Deferred revenue, net of current portion	740	1,217
Other non-current liabilities	8	16
TOTAL LIABILITIES	21,513	25,985
Commitments and Contingencies (Note 7)
STOCKHOLDERS’ EQUITY
Preferred stock, $0.0001 par value; 10,000,000 shares authorized as of March 31, 2022 and December 31, 2021; no shares issued and outstanding as of March 31, 2022 and December 31, 2021	0	0
Common stock, $0.0001 par value; 500,000,000 shares authorized as of March 31, 2022 and December 31, 2021; 49,419,873 shares and 49,355,130 shares issued and outstanding as of March 31, 2022 and December 31, 2021, respectively	5	5
Additional paid-in capital	428,050	425,765
Accumulated other comprehensive loss	(153)	(20)
Accumulated deficit	(366,245)	(341,809)
TOTAL STOCKHOLDERS’ EQUITY	61,657	83,941
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 83,170	$ 109,926