UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 4,904	$ 19,207
Restricted cash	261	261
Prepaid expenses and other current assets	1,238	661
Total current assets	6,403	20,129
Property and equipment, net	143	169
Operating lease right-of-use asset	654	825
Total assets	7,200	21,123
Current liabilities:
Accounts payable	2,434	3,020
Accrued expenses	2,230	2,799
Current portion of long-term debt	1,536	3,980
Advances from collaboration partners	12,535	12,535
Current portion of operating lease liability	667	712
Derivative liabilities	58	45
Total current liabilities	19,460	23,091
Long-term debt, net of current portion	4,027	8,557
Operating lease liability	6	135
Total liabilities	23,493	31,783
Commitments and contingencies
Stockholders' deficit:
Preferred stock, $0.01 par value per share, 5,000,000 shares authorized, no shares issued or outstanding as of March 31, 2023 and December 31, 2022	0	0
Common stock, $0.01 par value per share, 500,000,000 shares authorized,2,166,356 shares issued and outstanding as of March 31, 2023 and December 31, 2022	22	22
Additional paid-in capital	264,303	263,706
Accumulated deficit	(280,618)	(274,388)
Total stockholders' (deficit) equity	(16,293)	(10,660)
Total liabilities and stockholders' deficit	$ 7,200	$ 21,123