Condensed Consolidated Balance Sheets - USD ($)	Mar. 31, 2016	Dec. 31, 2015
Current assets:
Cash	$ 31,188,527	$ 29,349,124
Trade accounts receivable	70,259
Prepaid expenses and other current assets	3,608,102	2,311,385
Total current assets	34,866,888	31,660,509
Property and equipment, net	2,210,389	2,162,771
Other non-current assets	128,020	126,781
Total assets	37,205,297	33,950,061
Current liabilities:
Trade accounts payable	1,711,028	1,058,536
Accrued expenses and other current liabilities	2,322,044	1,739,380
Deferred revenues, current portion	2,464,722
Total current liabilities	6,497,794	2,797,916
Deferred revenue, net of current portion	3,491,690
Other long-term liabilities	39,742	23,852
Total liabilities	10,029,226	2,821,768
Stockholders' equity:
Common stock, $0.001 par value per share, 300,000,000 shares authorized and 39,833,023 shares issued and outstanding at March 31, 2016 and December 31, 2015	39,833	39,833
Additional paid-in capital	112,595,106	112,226,723
Accumulated other comprehensive loss	(1,432,125)	(1,272,574)
Accumulated deficit	(84,026,743)	(79,865,689)
Total stockholders' equity	27,176,071	31,128,293
Total liabilities and stockholders' equity	$ 37,205,297	$ 33,950,061