Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 18,089	$ 14,949
Marketable securities		18,576
Accounts receivable	973	402
Insurance recovery (Note 9)		15,000
Clinical trial retainers	567	1,027
Other prepaid expenses and other current assets	370	229
Total current assets	19,999	50,183
Other assets	7	15
Total assets	20,006	50,198
Current liabilities:
Accounts payable	2,822	2,436
Accrued clinical trial costs and contract research	6,991	8,321
Other accrued liabilities	1,684	2,458
Loans payable, net of discount	2,388
Deferred revenue	1,342	395
Deferred research and development reimbursements	534	901
Estimated settlement liability (Note 9)	1,406	17,073
Other liabilities (Note 6)		540
Total current liabilities	17,167	32,124
Loans payable, net of current portion and discount	16,342	18,477
Deferred revenue	3,749	1,302
Deferred research and development reimbursements	118	222
PIPE Warrant liability (Note 7)	26,985	37,746
Other liabilities (Note 6)	1,090	1,090
Total liabilities	65,451	90,961
Stockholders’ deficit:
Preferred stock, $.001 par value: 5,000 shares authorized at June 30, 2018 and December 31, 2017; no shares issued and outstanding at each of June 30, 2018 and December 31, 2017
Common stock, $.001 par value: 250,000 shares authorized at June 30, 2018 and December 31, 2017; 118,995 and 118,325 shares issued and outstanding as of June 30, 2018 and December 31, 2017, respectively	119	118
Additional paid-in capital	549,099	546,092
Accumulated other comprehensive income (loss)	1	(4)
Accumulated deficit	(594,664)	(586,969)
Total stockholders’ deficit	(45,445)	(40,763)
Total liabilities and stockholders’ deficit	$ 20,006	$ 50,198