Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018
Operating activities:
Net loss	$ (85,058)	$ (80,277)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation and amortization	878	326
Stock-based compensation	7,552	6,325
Amortization of debt discount and issuance costs	382	291
Loss on extinguishment of debt	7,155	0
Changes in operating assets and liabilities:
Accounts receivable	(8,435)	(2,923)
Grants and other receivables	10	(136)
Prepaid expenses and other assets	(221)	(380)
Inventory	2,753	(4,686)
Accounts payable	(1,928)	2,566
Accrued expenses and other liabilities	4,203	7,271
Cash used in operating activities	(72,709)	(71,623)
Investing activities:
Purchases of property and equipment	(485)	(1,450)
Cash used in investing activities	(485)	(1,450)
Financing activities:
Proceeds from the sale of common stock	0	63,969
Proceeds from long-term debt	77,596	0
Proceeds from the issuance of warrants	2,404	0
Cash paid for financing costs	(3,277)	(6,464)
Proceeds from issuance of common stock under employee stock purchase plan	612	739
Proceeds from the exercise of stock options	542	1,418
Repayment of Athyrium debt facility	(80,179)	0
Cash (used in) provided by financing activities	(2,302)	59,662
Effects of exchange rate changes on cash and cash equivalents	(11)	41
Net decrease in cash, cash equivalents and restricted cash	(75,507)	(13,370)
Cash, cash equivalents and restricted cash at beginning of period	201,011	234,875
Cash, cash equivalents and restricted cash at end of period	125,504	221,505
Supplemental disclosure of noncash activities:
Fixed asset purchases within accounts payable and accrued expenses	17	172
Fixed asset additions acquired through tenant allowance	0	361
Financing costs within accounts payable and accrued expenses	280	82
Recognition of initial right-of-use assets	2,479	0
Recognition of initial lease liabilities	$ 2,956	$ 0