Unaudited Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 245,735	$ 125,699
Prepaid expenses and other current assets	2,198	2,043
Income tax receivable	1,764	882
Total current assets	249,697	128,624
Property and equipment, net	97	173
Right-of-use asset, net	144	496
Income tax receivable, non-current	0	882
Other assets	12	12
Total assets	249,950	130,187
Current liabilities
Accrued research and development expenses	7,131	6,860
Accounts payable and accrued expenses	4,634	5,629
Lease liability	53	495
Total current liabilities	11,818	12,984
Lease liability, non-current	91	0
Total liabilities	11,909	12,984
Stockholders' equity
Preferred stock—$0.001 par value, 5,000,000 shares authorized, no shares issued or outstanding	0	0
Common stock—$0.001 par value, 200,000,000 shares authorized, 89,488,531 and 49,627,064 shares issued and outstanding at June 30, 2020 and December 31, 2019, respectively	89	50
Additional paid-in capital	752,143	597,679
Accumulated deficit	(514,191)	(480,526)
Total stockholders' equity	238,041	117,203
Total liabilities and stockholders' equity	$ 249,950	$ 130,187