Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Operating activities
Net loss	$ (25,777)	$ (14,219)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	186	172
Stock-based compensation expense	2,903	2,462
Amortization of debt issuance costs	232	220
Amortization of premium/discount on investments	76	18
Change in fair value of foreign currency derivative	1,804	1,543
Changes in operating assets and liabilities:
Receivables	423	(796)
Inventory	(7)	(155)
Prepaid expenses and other assets	(1,015)	(284)
Deferred collaboration expense		18
Accounts payable and accrued expenses	152	1,642
Interest payable	1,370	1,301
Deferred revenue		(449)
Net cash used in operating activities	(19,653)	(8,527)
Investing activities
Acquisitions of property and equipment	(35)	(3)
Purchases of investments	(4,327)
Sales and maturities of investments	20,289	14,136
Net cash provided by investing activities	15,927	14,133
Financing activities
Sale of common stock, net		47,750
Payment of senior credit facility	(1,725)
Net proceeds from common stock issued under stock-based compensation plans	268	950
Increase in lease financing obligation	(19)
Net cash (used in) provided by financing activities	(1,476)	48,700
(Decrease) increase in cash, cash equivalents and restricted cash	(5,202)	54,306
Cash, cash equivalents and restricted cash at beginning of period	53,568	23,650
Cash, cash equivalents and restricted cash at end of period	$ 48,366	$ 77,956

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