CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 10,780	$ 36,455
Available-for-sale securities	123,658	112,292
Accounts receivable from related party	10,000	11,402
Prepaid expenses and other current assets	6,805	4,042
Total current assets	151,243	164,191
Available-for-sale securities, long-term	5,003	13,547
Property and equipment, net	5,110	5,611
Right-of-use asset, operating	11,116
Right-of-use asset, finance	185
Other assets	1,128	1,128
Total assets	173,785	184,477
Current liabilities:
Accounts payable	1,211	4,012
Accrued expenses and other current liabilities	5,328	7,712
Deferred collaboration liability, current	7,888	8,118
Deferred rent and lease incentive obligation, current		696
Operating lease liability, current	3,502
Finance lease liability, current	180
Total current liabilities	18,109	20,538
Long-term liabilities:
Deferred collaboration liability, long term	13,660	16,431
Deferred rent and lease incentive obligation, long term		4,208
Operating lease liability, long term	12,326
Other long-term liabilities	1,570	1,611
Total liabilities	45,665	42,788
Commitments and contingencies (Note 7)
Stockholders' equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized, no shares issued and outstanding at March 31, 2022 and December 31, 2021
Common stock, $0.001 par value; 200,000,000 shares authorized, 24,964,502 shares issued and 24,956,556 shares outstanding at March 31, 2022; 200,000,000 shares authorized, 24,964,520 shares issued and 24,951,983 shares outstanding at December 31, 2021	25	25
Additional paid-in capital	357,150	356,308
Accumulated other comprehensive loss	(527)	(132)
Accumulated deficit	(228,528)	(214,512)
Total stockholders' equity	128,120	141,689
Total liabilities and stockholders' equity	$ 173,785	$ 184,477