Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 88,925	$ 59,321
Restricted cash	565	560
Marketable securities	79,251	177,140
Accounts receivable, net	21,528	16,758
Inventory	4,911	6,210
Prepaid expenses	15,201	13,842
Other current assets	858	1,202
Total current assets	211,239	275,033
Property and equipment, net	2,616	4,003
Intangible assets	6,783	7,382
Right of use assets - operating leases	6,443
Other assets	412	544
Total assets	227,493	286,962
Current liabilities:
Accounts payable	4,608	4,226
Accrued expenses and other current liabilities	49,082	42,203
Operating lease liability, current	1,904
Total current liabilities	55,594	46,429
Notes payable	191,444	179,806
Operating lease liability, long term	4,681
Other non-current liabilities	24	95
Total liabilities	251,743	226,330
Commitments and contingencies
Stockholders’ equity (deficit):
Common stock, $0.0001 par value; 200,000,000 shares authorized, 46,173,170 shares and 45,563,693 shares issued and outstanding at September 30, 2019 and December 31, 2018, respectively	5	5
Additional paid-in-capital	1,187,623	1,165,003
Accumulated other comprehensive loss	21	(755)
Accumulated deficit	(1,211,899)	(1,103,621)
Total stockholders’ equity (deficit)	(24,250)	60,632
Total liabilities and stockholders’ equity (deficit)	$ 227,493	$ 286,962