Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 66,901	$ 59,321
Restricted cash	563	560
Marketable securities	121,576	177,140
Accounts receivable, net	23,649	16,758
Inventory	5,157	6,210
Prepaid expenses	8,186	13,842
Other current assets	873	1,202
Total current assets	226,905	275,033
Property and equipment, net	2,983	4,003
Intangible assets	6,982	7,382
Right of use assets - operating leases	6,940
Other assets	486	544
Total assets	244,296	286,962
Current liabilities:
Accounts payable	6,041	4,226
Accrued expenses and other current liabilities	43,759	42,203
Operating lease liability, current	2,029
Total current liabilities	51,829	46,429
Notes payable	187,434	179,806
Operating lease liability, long term	5,120
Other non-current liabilities	47	95
Total liabilities	244,430	226,330
Commitments and contingencies
Stockholders’ equity (deficit):
Common stock, $.0001 par value; 200,000,000 shares authorized, 46,125,197 shares and 45,563,693 shares issued and outstanding at June 30, 2019 and December 31, 2018, respectively	5	5
Additional paid-in-capital	1,181,761	1,165,003
Accumulated other comprehensive loss	(45)	(755)
Accumulated deficit	(1,181,855)	(1,103,621)
Total stockholders’ equity (deficit)	(134)	60,632
Total liabilities and stockholders’ equity (deficit)	$ 244,296	$ 286,962