CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net loss	$ (29,234)	$ (9,902)	$ (27,608)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	26	25	36
Amortization of warrant issuance costs	91	0	0
Stock-based compensation	7,275	8,189	7,563
Change in value of derivative liability	117	(2,238)	(1,608)
Changes in assets and liabilities:
Prepaid expenses and other current assets	(2)	(296)	(243)
Prepaid expenses - Non-current	385	(3,144)	0
Prepaid taxes	0	0	14,963
Deferred revenue	1,000	1,333	667
Accounts payable and accrued liabilities	(1,044)	1,806	(1,449)
Accrued payroll and related expenses	1,156	0	0
Royalty payable	(6,100)	6,100	0
Related-party payable	(70)	81	0
Income tax liability	(8)	13	395
Net cash provided by (used in) operating activities	(26,408)	1,967	(7,284)
Cash flows from investing activities:
Purchase of property and equipment	(10)	(35)	(7)
Purchase of investments	(10,673)	(45,500)	(92,729)
Proceeds from sale, maturity of investments	23,287	42,766	99,362
Net cash provided by (used in) investing activities	12,604	(2,769)	6,626
Cash flows from financing activities:
Proceeds from sale of common stock	3,276	0	0
Proceeds from exercise of options	165	278	170
Proceeds from exercise of warrants	431	9	0
Net cash provided by financing activities	3,872	287	170
Net decrease in cash and cash equivalents	(9,932)	(515)	(488)
Cash and cash equivalents, beginning of year	18,658	19,173	19,661
Cash and cash equivalents, end of year	8,726	18,658	19,173
Supplemental disclosure of cash flow information:
Cash paid during the year for taxes	6	2	0
Cash paid during the year for interest	$ 0	$ 0	$ 0