Condensed Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 4,272	$ 5,404
Short-term investments	12,406	19,600
Accounts receivable (net of allowances of $87 at March 31, 2017 and $73 at December 31, 2016)	2,076	1,154
Inventories	3,462	3,782
Prepaid expenses and other current assets	2,905	2,486
Total current assets	25,121	32,426
Property and equipment (net of accumulated depreciation of $21,488 and $21,376 at March 31, 2017 and December 31, 2016, respectively)	1,191	1,297
Goodwill	6,399	6,399
Long-term restricted investments	150	150
Other long-term assets	236	236
Total assets	33,097	40,508
Current liabilities:
Accounts payable	1,138	2,086
Accrued liabilities	3,289	5,060
Contract research liabilities	787	783
Deferred revenue, current portion	1,016	968
Term loan, current portion, net	1,272	19,853
Total current liabilities	7,502	28,750
Deferred revenue, non-current portion	1,822	1,879
Term loan, non-current portion, net	18,597
Other long-term liabilities	1,929	1,541
Commitments and contingencies
Stockholders’ equity:
Common stock	14	14
Additional paid-in capital	451,429	448,404
Accumulated other comprehensive income (loss)	(5)	(3)
Accumulated deficit	(448,191)	(440,077)
Stockholders’ equity	3,247	8,338
Total liabilities and stockholders’ equity	$ 33,097	$ 40,508