Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Assets
Cash and cash equivalents	$ 30,760	$ 26,731
Restricted cash	4,629	1,544
Investments	61,387	77,736
Receivables from collaborations	3,602	4,293
Inventory	1,000	1,649
Prepaid expenses and other current assets	2,341	2,399
Total current assets	103,719	114,352
Investments	741	22,376
Property and equipment, net	7,551	9,135
Other assets	4,333	978
Total assets	116,344	146,841
Liabilities and Stockholders’ Equity
Accounts payable	8,298	7,769
Accrued expenses	19,343	15,938
Interest payable	14,745	11,848
Deferred collaboration revenue	221	221
Senior credit facility		4,580
Non-recourse notes payable	29,341	29,121
Total current liabilities	71,948	69,477
Deferred rent		54
Other non-current liabilities	3,742	2,703
Senior credit facility	49,847	25,372
Stockholders’ equity:
Preferred stock, $0.001 par value; shares authorized — 5,000; no shares issued and outstanding
Common stock, $0.01 par value: shares authorized — 200,000; shares issued and outstanding — 110,370 in 2019 and 110,063 in 2018	1,104	1,101
Additional paid-in capital	790,076	780,400
Accumulated other comprehensive income (loss)	41	(297)
Accumulated deficit	(800,414)	(731,969)
Total stockholders’ equity	(9,193)	49,235
Total liabilities and stockholders’ equity	$ 116,344	$ 146,841