Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows from operating activities:
Net loss	$ (25,001)	$ (7,857)
Adjustments to reconcile net loss to cash used in operating activities
Depreciation and amortization	90	177
Stock-based compensation expense	1,185	698
Amortization of convertible debt discount and deferred transaction costs	643
Financing costs, derivative liability and warrants	997
Change in value of derivative liability	(386)
Changes in operating assets and liabilities:
Receivables	110	865
Prepaid and other current assets	2,196	44
Other assets	81	30
Accounts payable	(1,011)	(765)
Accrued compensation	184	305
Current deferred revenue - related party		(790)
Accrued liabilities	(693)	1,994
Deferred rent	(37)	(42)
Accrued clinical and cost of other studies, non-current		203
Deferred revenue - related party		(2,845)
Facility lease exit obligation	(104)	(144)
Net cash used in operating activities	(21,746)	(8,127)
Cash flows from investing activities:
Transfer to restricted cash	(2,016)
Capital expenditures	(69)
Net cash used in investing activities	(2,085)
Cash flows from financing activities:
Proceeds from issuance of convertible debt	3,050
Proceeds from issuance of convertible debt - related party	19,950
Proceeds from issuance of common stock	60	121
Payments for debt issuance costs	(2,192)
Net cash provided by financing activities	20,868	121
Net decrease in cash and cash equivalents	(2,963)	(8,006)
Cash and cash equivalents at beginning of period	31,462	47,990
Cash and cash equivalents at end of period	28,499	$ 39,984
Non-cash disclosures of financing activities:
Reclassification of derivative liability to equity	8,362
Reclassification of warrants to equity	11
Debt discount from warrants	662
Accrued financing costs	$ 221