Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 27,259	$ 47,758
Accounts receivable, net	5,646	6,294
Inventories, net	8,609	6,824
Prepaid expense and other current assets	1,469	1,200
Total current assets	42,983	62,076
Property and equipment, net	6,713	6,097
Right-of-use assets	2,494
Other assets	563	447
Total assets	52,753	68,620
Current liabilities:
Accounts payable	4,930	4,916
Accrued expense and other current liabilities	11,226	8,851
Current portion of operating lease obligations	377
Current portion of financing lease obligations	132
Current portion of financing lease obligations		123
Total current liabilities	16,665	13,890
Long-term debt, related parties (net)	41,680	40,192
Operating lease obligations	2,244
Deferred rent		109
Financing lease liabilities	72	140
Total liabilities	60,661	54,331
Commitments and contingencies
Stockholders' equity (deficit)
Convertible preferred stock, $0.001 par value, 50,000,000 shares authorized at June 30, 2019; 2,750,000 shares issued and outstanding at June 30, 2019 and December 31, 2018. (aggregate liquidation value of $32,511 and $31,411 at June 30, 2019 and December 31, 2018, respectively)	3	3
Common stock, $0.001 par value, 300,000,000 shares authorized; 5,988,616 shares issued and 5,988,224 shares outstanding at June 30, 2019 and 4,997,544 shares issued and 4,997,152 shares outstanding at December 31, 2018.	6	5
Additional paid-in capital	540,681	534,176
Accumulated deficit	(548,574)	(519,871)
Treasury stock, at cost (392 shares)	(24)	(24)
Total stockholders' equity (deficit)	(7,908)	14,289
Total liabilities and stockholders' equity (deficit)	$ 52,753	$ 68,620