Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 39,848	$ 29,785
Marketable securities	28,996	17,960
Accounts receivable	1,052	1,631
Clinical trial retainers	476	589
Other prepaid expenses and other current assets	1,270	635
Total current assets	71,642	50,600
Property and equipment, net	210
Operating lease right-of-use asset	1,012
Other assets	158
Total assets	73,022	50,600
Current liabilities:
Accounts payable	1,999	1,466
Accrued clinical trial costs and contract research	5,925	5,680
Other accrued liabilities	3,411	2,336
Operating lease liability	436
Loans payable, net of discount		9,569
Deferred revenue	1,974	1,974
Deferred research and development reimbursements	240	93
PIPE Warrant liability (Note 7)	1,913
Other liabilities (Note 6)	790
Total current liabilities	16,688	21,118
Loans payable, net of current portion and discount	13,617	6,197
Deferred revenue	1,072	2,552
PIPE Warrant liability (Note 7)		5,097
Operating lease liability, non-current	379
Other liabilities (Note 6)	1,043	790
Total liabilities	32,799	35,754
Stockholders’ equity:
Preferred stock, $.001 par value: 5,000 shares authorized at September 30, 2020 and December 31, 2019; no shares issued and outstanding at each of September 30, 2020 and December 31, 2019
Common stock, $.001 par value: 50,000 shares authorized at September 30, 2020 and December 31, 2019; 25,808 shares issued and outstanding at September 30, 2020 and 16,081 issued and outstanding at December 31, 2019	26	16
Additional paid-in capital	649,897	600,451
Accumulated other comprehensive income	1
Accumulated deficit	(609,701)	(585,621)
Total stockholders’ equity	40,223	14,846
Total liabilities and stockholders’ equity	$ 73,022	$ 50,600