Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 34,545	$ 107,143
Marketable securities	53,662	16,213
Accounts receivable (inclusive of $23 and $23 from a related party at June 30, 2022 and December 31, 2021, respectively)	23	59
Prepaid expenses and other current assets	3,602	2,729
Restricted cash-current	339	250
Total current assets	92,171	126,394
Property and equipment, net	3,401	3,994
Right-of-use assets	10,817	12,863
Restricted cash	1,029	1,118
Total assets	107,418	144,369
Current liabilities:
Accounts payable	1,051	2,344
Accrued expenses and other current liabilities	6,505	8,998
Lease liabilities, current portion	4,441	4,845
Current portion of longterm debt	5,000	1,667
Deferred revenue from related party, current portion	16,323	17,034
Total current liabilities	33,320	34,888
Deferred revenue from related party, net of current portion		5,333
Lease liability, net of current portion	6,793	8,577
Long-term debt, net of discount and current portion	15,218	18,411
Other liabilities	281
Total liabilities	55,612	67,209
Commitments and contingencies (Note 9)
Stockholders' equity
Common stock, par value $0.001 per share; 175,000,000 shares authorized at June 30, 2022 and December 31, 2021; 32,399,257 and 32,359,895 shares issued and outstanding at June 30, 2022 and December 31, 2021, respectively	32	32
Preferred stock, par value $0.001 per share; 25,000,000 shares authorized at June 30, 2022 and December 31, 2021; no shares issued and outstanding at June 30, 2022 and December 31, 2021
Additional paid-in capital	293,774	290,377
Accumulated other comprehensive loss	(556)	(10)
Accumulated deficit	(241,444)	(213,239)
Total stockholders' equity	51,806	77,160
Total liabilities and stockholders' equity	$ 107,418	$ 144,369