Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash Flows From Operating Activities:
Net Loss	$ (3,058)	$ (11,078)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	1,135	1,052
Change in fair value of warrant liabilities	(5,090)	498
Depreciation	57	37
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(851)	2,403
Deposits and other assets	0	(12)
Accounts payable	1,803	184
Accrued expenses	(493)	649
Accrued employee benefits	474	592
Deferred rent	15	1
Net Cash Used In Operating Activities	(6,008)	(5,674)
Cash Flows From Investing Activities:
Purchases of property and equipment	(11)	(44)
Net Cash Used In Investing Activities	(11)	(44)
Cash Flows From Financing Activities:
Proceeds from issuance of common stock from stock option exercises	166	0
Proceeds from “at the market” stock issuance	269	0
Net Cash Provided By Financing Activities	435	0
Net decrease in cash	(5,584)	(5,718)
Cash at beginning of period	19,055	20,818
Cash at end of period	13,471	15,100
Supplemental disclosures of cash flow information:
Cash paid for interest	0	0
Cash paid for taxes	$ 0	$ 0