Condensed Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 17,124	$ 5,311
Investments	1,756	12,967
Prepaid expenses and other current assets	765	1,247
Restricted cash	25	25
Total current assets	19,670	19,550
Operating lease, right-of-use asset	5,723	6,060
Property and equipment, net	164	295
Restricted cash, non-current	568	568
Total assets	26,125	26,473
Current liabilities:
Accounts payable	993	1,452
Accrued expenses and other current liabilities	3,272	3,941
Paycheck Protection Program loan, current portion	171
Operating lease liability, current portion	490	446
Total current liabilities	4,926	5,839
Paycheck Protection Program loan, net of current portion	213
Operating lease liability, net of current portion	4,332	4,586
Total liabilities	9,471	10,425
Commitments and contingencies (Note 11)
Stockholders’ equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized and no shares issued and outstanding at June 30, 2020 and December 31, 2019, respectively
Common stock, $0.001 par value; 150,000,000 shares authorized at June 30, 2020 and December 31, 2019; 39,261,576 and 27,810,358 shares issued and outstanding at June 30, 2020 and December 31, 2019, respectively	39	28
Additional paid-in capital	225,890	214,148
Accumulated other comprehensive gain/(loss)	(2)	7
Accumulated deficit	(209,273)	(198,135)
Total stockholders’ equity	16,654	16,048
Total liabilities and stockholders’ equity	$ 26,125	$ 26,473