Consolidated Balance sheets - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 35,102	$ 80,819
Marketable securities	1,399	4,498
Accounts receivable	5,000
Prepaid expenses and other current assets	1,207	2,264
Total current assets	42,708	87,581
Property and equipment, net	387	874
Operating lease right-of-use assets	18,543	23,678
Deposits	366	386
Restricted cash	928	2,066
Assets held-for-sale	0	250
Total assets	62,932	114,835
Current liabilities:
Accounts payable	1,839	7,384
Accrued expenses and other current liabilities	4,846	7,851
Current portion of long-term debt	5,805	2,891
Operating lease liabilities	5,064	4,468
Current portion of finance lease obligation	48	166
Deferred revenue	5,061	8,104
Total current liabilities	22,663	30,864
Long-term debt, net of discount and current portion	7,357	13,237
Operating lease liabilities, net of current portion	9,415	14,479
Finance lease obligation, net of current portion	0	48
Total liabilities	39,435	58,628
Commitments and contingencies (Note 12)
Stockholders' equity/Members' deficit:
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued and outstanding as of December 31, 2021 and 2020, respectively	0	0
Common stock, $0.001 par value; 125,000,000 shares authorized; 10,644,714 shares and 10,193,831 shares issued and outstanding as of December 31, 2021 and 2020, respectively	11	10
Additional paid-in capital	210,799	204,007
Accumulated deficit	(187,313)	(147,810)
Total stockholders' equity	23,497	56,207
Total liabilities and stockholders' equity	$ 62,932	$ 114,835