CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net loss	$ (10,355)	$ (18,559)
Adjustments required to reconcile net loss to net cash used in operating activities:
Stock-based compensation	379	245
Depreciation and impairment of fixed assets	258	186
Accrued severance pay, net	4	9
Increase in fair value of warrants to purchase Ordinary Shares	4,201	12,715
Decrease (increase) in other accounts receivable and prepaid expenses	7	(33)
Decrease in deferred revenue		(315)
Increase (decrease) in trade payables	54	(1,553)
Increase (decrease) in other accounts payable and accrued expenses	120	(672)
Net cash used in operating activities	(5,332)	(7,977)
Cash flows from investing activities:
Purchase of property and equipment	(482)	(717)
Decrease in long-term deposit		58
Net cash used in investing activities	(482)	(659)
Net decrease in cash and cash equivalents	(5,814)	(8,636)
Cash and cash equivalents at the beginning of the period	32,453	23,215
Cash and cash equivalents at the end of the period	26,639	14,579
Supplemental disclosure of non-cash investing and financing activities:
Purchase of property and equipment	267	31
Cash paid during the period:
Cash paid for taxes	$ 16	$ 166