Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 24,767	$ 19,493
Prepaid expenses and other current assets	751	163
Total current assets	25,518	19,656
Property, equipment and leasehold improvements, net	76	85
Restricted cash - non current	110	110
Operating lease right-of-use assets	853	928
Prepaid clinical trial expenses	1,122	1,122
Other assets	4	9
Total assets	27,683	21,910
Current liabilities:
Accounts payable	640	481
Operating lease liabilities	336	327
Accrued expenses	499	1,164
Total current liabilities	1,475	1,972
Other liabilities	79	59
Operating lease liabilities - non current	605	693
Total liabilities	2,159	2,724
Commitments and contingencies (Note 5)
Stockholders’ equity:
Common stock, $0.00001 par value, authorized 50,000,000 shares; 34,264,756 shares issued and outstanding, including 6,302 shares of unvested restricted stock, at March 31, 2021; authorized 50,000,000 shares; 23,631,886 shares issued and outstanding, including 6,302 shares of unvested restricted stock, at December 31, 2020	3	3
Additional paid-in capital	255,978	247,417
Accumulated deficit	(230,457)	(228,234)
Total stockholders’ equity	25,524	19,186
Total liabilities and stockholders’ equity	$ 27,683	$ 21,910