Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 147,528	$ 106,046
Prepaid expenses and other current assets	2,369	2,706
Total current assets	149,897	108,752
Property and equipment, net	113	168
Operating lease right-of-use asset	589
Other assets	729	549
TOTAL ASSETS	151,328	109,469
CURRENT LIABILITIES:
Accrued and other liabilities	7,170	8,812
Accounts payable	1,019	1,287
Warrant liabilities	45,935
Securities issuance obligation	10,485
Total current liabilities	64,609	10,099
Operating lease liability	374
Term loan		4,891
TOTAL LIABILITIES	64,983	14,990
Commitments and Contingencies (Note 8)
STOCKHOLDERS' EQUITY:
Preferred stock, $0.001 par value; 10,000,000 shares authorized as of December 31, 2019 and December 31, 2018; 103,000 shares Series A convertible voting preferred stock, issued and outstanding as of December 31, 2019 and nil shares issued and outstanding as of December 31, 2018	1
Common stock, $0.001 par value; 500,000,000 shares authorized as of December 31, 2019 and 2018; 1,867,176 and 1,859,120 shares issued and outstanding as of December 31, 2019 and 2018	74	74
Additional paid-in capital	851,957	771,817
Accumulated deficit	(765,687)	(677,412)
TOTAL STOCKHOLDERS' EQUITY	86,345	94,479
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 151,328	$ 109,469