CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 50,771	$ 16,034
Short-term investments		24,962
Grants receivable	241	1,232
Prepaid expenses	2,611	4,560
Other current assets	1,124	2,218
Total current assets	54,747	49,006
Property and equipment, net	267	345
Operating lease right-of-use assets	1,387	1,620
Other assets	63	63
Total assets	56,464	51,034
Current liabilities:
Accounts payable	1,596	1,304
Accrued expenses and other current liabilities	4,561	6,252
Total current liabilities	6,157	7,556
Operating lease liabilities, net of current portion	1,020	1,321
Total liabilities	7,177	8,877
Commitments (Notes 5 and 11)
Stockholders' equity:
Common stock, par value $0.001; 125,000,000 shares authorized and 27,291,563 and 13,291,563 shares issued and outstanding as of June 30, 2020 and December 31, 2019, respectively	27	13
Additional paid-in capital	211,881	176,103
Accumulated other comprehensive income
Accumulated deficit	(162,621)	(133,959)
Total stockholders' equity	49,287	42,157
Total liabilities and stockholders' equity	$ 56,464	$ 51,034