Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
CURRENT ASSETS:
Cash and cash equivalents	$ 123,233	$ 147,528
Prepaid expenses and other current assets	1,392	2,369
Total current assets	124,625	149,897
Property and equipment, net	97	113
Operating lease right-of-use asset	504	589
Other assets	667	729
TOTAL ASSETS	125,893	151,328
CURRENT LIABILITIES:
Accrued and other liabilities	6,698	7,170
Accounts payable	1,983	1,019
Deferred Revenue	300
Warrant liabilities		45,935
Securities issuance obligation		10,485
Total current liabilities	8,981	64,609
Operating lease liability	261	374
TOTAL LIABILITIES	9,242	64,983
Commitments and Contingencies (Note 8)
STOCKHOLDERS' EQUITY:
Preferred stock, $0.001 par value; 10,000,000 shares authorized as of June 30, 2020 and December 31, 2019; nil shares issued and outstanding as of June 30, 2020 and 103,000 shares of Series A convertible voting preferred stock issued and outstanding as of December 31, 2019		1
Common stock, $0.001 par value; 500,000,000 shares authorized as of June 30, 2020 and December 31, 2019; 10,395,732 and 1,867,176 shares issued and outstanding as of June 30, 2020 and December 31, 2019	10	74
Additional paid-in capital	930,702	851,957
Accumulated deficit	(814,061)	(765,687)
TOTAL STOCKHOLDERS' EQUITY	116,651	86,345
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 125,893	$ 151,328