Condensed Consolidated Balance sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 16,060	$ 35,102
Marketable securities	1,400	1,399
Accounts receivable	0	5,000
Prepaid expenses and other current assets	2,957	1,207
Total current assets	20,417	42,708
Property and equipment, net	182	387
Operating lease right-of-use assets	10,082	18,543
Deposits		366
Restricted cash	878	928
Total assets	31,559	62,932
Current liabilities:
Accounts payable	2,080	1,839
Accrued expenses and other current liabilities	2,872	4,846
Current portion of long-term debt	0	5,805
Operating lease liabilities	604	5,064
Current portion of finance lease obligation	0	48
Short-term borrowings	1,152	0
Deferred revenue	4,038	5,061
Total current liabilities	10,746	22,663
Long-term debt, net of discount and current portion	0	7,357
Operating lease liabilities, net of current portion	9,110	9,415
Total liabilities	19,856	39,435
Commitments and contingencies (Note 11)
Stockholders' equity/(deficit):
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued and outstanding as of March 31, 2022 and December 31, 2021, respectively	0	0
Common stock, $0.001 par value; 125,000,000 shares authorized; 10,846,740 shares and 10,644,714 shares issued and outstanding as of March 31, 2022 and December 31, 2021, respectively	11	11
Additional paid-in capital	212,386	210,799
Accumulated deficit	(200,694)	(187,313)
Total stockholders' equity	11,703	23,497
Total liabilities and stockholders' equity	$ 31,559	$ 62,932