Condensed Consolidated Balance Sheets (unaudited) - USD ($)	Mar. 31, 2017	Dec. 31, 2016
CURRENT ASSETS
Cash and cash equivalents	$ 16,801,000	$ 47,748,000
Marketable securities	41,067,000	15,754,000
Accounts receivable - grant	981,000	1,215,000
Prepaid expenses and other current assets	1,456,000	1,707,000
Total current assets	60,305,000	66,424,000
Property and equipment, net	822,000	599,000
Other non-current assets	140,000	40,000
TOTAL ASSETS	61,267,000	67,063,000
CURRENT LIABILITIES
Accounts payable	267,000	168,000
Deferred revenue	51,000	71,000
Accrued and other current liabilities	3,639,000	3,726,000
Total current liabilities	3,957,000	3,965,000
Other non-current liabilities	127,000	132,000
TOTAL LIABILITIES	4,084,000	4,097,000
Commitments and Contingencies (Notes 9 and 11)
STOCKHOLDERS’ EQUITY
Preferred stock, $0.0001 par value; 10,000,000 shares authorized as of March 31, 2017 and December 31, 2016; no shares issued and outstanding as of March 31, 2017 and December 31, 2016
Common stock, $0.0001 par value; 500,000,000 shares authorized as of March 31, 2017 and December 31, 2016; 13,452,260 shares and 13,430,833 shares issued and outstanding as of March 31, 2017 and December 31, 2016, respectively	1,000	1,000
Additional paid-in capital	108,743,000	108,246,000
Accumulated other comprehensive loss	(37,000)	(4,000)
Accumulated deficit	(51,524,000)	(45,277,000)
TOTAL STOCKHOLDERS’ EQUITY	57,183,000	62,966,000
TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY	$ 61,267,000	$ 67,063,000