Condensed Consolidated Balance sheets - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 11,846	$ 35,102
Marketable securities	0	1,399
Accounts receivable	0	5,000
Restricted cash, current	828	0
Prepaid expenses and other current assets	1,854	1,207
Total current assets	14,528	42,708
Property and equipment, net	60	387
Operating lease right-of-use assets	831	18,543
Deposits	0	366
Restricted cash	50	928
Total assets	15,469	62,932
Current liabilities:
Accounts payable	1,599	1,839
Accrued expenses and other current liabilities	2,422	4,846
Current portion of long-term debt	0	5,805
Operating lease liabilities	559	5,064
Current portion of finance lease obligation	0	48
Short-term borrowings	578	0
Deferred revenue	2,381	5,061
Total current liabilities	7,539	22,663
Long-term debt, net of discount and current portion	0	7,357
Operating lease liabilities, net of current portion	0	9,415
Total liabilities	7,539	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 June 30, 2022 and December 31, 2021, respectively	0	0
Common stock, $0.001 par value; 125,000,000 shares authorized; 10,842,945 shares and 10,644,714 shares issued and outstanding as of June 30, 2022 and December 31, 2021, respectively	11	11
Additional paid-in capital	213,458	210,799
Accumulated deficit	(205,539)	(187,313)
Total stockholders' equity	7,930	23,497
Total liabilities and stockholders' equity	$ 15,469	$ 62,932