Unaudited Condensed Consolidated Statement of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities
Net loss	$ (23,078)	$ (12,877)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	63	45
Non-cash interest expense (debt discount and deferred costs)	17	27
Change in fair value of derivative liabilities	304	13
Stock-based compensation expense	1,154	525
Changes in assets and liabilities:
Prepaid expenses and other current assets	114	(2)
Inventory	(324)
Deposits and other assets	68
Accounts payable	3,839	(16)
Accrued expenses and other current liabilities	781	1,537
Accrued interest	(327)	194
Deferred rent	12	5
Net cash used in operating activities	(17,377)	(10,549)
Cash flows from investing activities
Capital expenditures	(362)	(61)
Net cash used in investing activities	(362)	(61)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs	45,738
Proceeds from exercise of stock options	36	19
Proceeds from notes payable	17,500
Repayments of notes payable	(13,284)
Net cash provided by financing activities	49,990	19
Net increase (decrease) in cash and cash equivalents	32,251	(10,591)
Cash and cash equivalents, at beginning of period	3,939	18,923
Cash and cash equivalents, at end of period	$ 36,190	$ 8,332