Consolidated Balance Sheets - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 13,915,094	$ 67,493,047
Short-term investments	23,978,022	0
Accounts receivable	100,460	98,736
Prepaid expenses and other assets	956,616	789,285
Total current assets	38,950,192	68,381,068
Property and equipment, net	3,826,915	2,690,579
Other assets	1,173,304	374,004
Total Assets	43,950,411	71,445,651
Current liabilities:
Accounts payable	1,130,536	1,040,868
Accrued liabilities	4,021,365	1,903,797
Deferred rent	285,246	30,614
Current portion of long-term debt	2,360,109	5,225,818
Total current liabilities	7,797,256	8,201,097
Long-term debt, less current portion	14,176,359	11,246,188
Derivative financial instruments—warrants	834,940	3,297,077
Deferred rent, net of current portion	1,373,717	0
Total liabilities	24,182,272	22,744,362
Commitments and contingencies
Stockholders’ equity
Preferred stock, $0.001 par value, 20,000,000 shares authorized, 60,600 shares outstanding at each of December 31, 2016 and 2015, designated as Series A Convertible Preferred Stock with liquidation preference of $606,000 at each of December 31, 2016 and 2015	60	60
Common stock, $0.0001 par value, 150,000,000 shares authorized at December 31, 2016 and 2015; 30,696,791 and 29,737,601 issued and outstanding at December 31, 2016 and 2015, respectively	3,070	2,974
Additional paid-in capital	167,890,984	157,585,498
Accumulated other comprehensive loss	(10,773)	0
Accumulated deficit	(148,115,202)	(108,887,243)
Total stockholders’ equity	19,768,139	48,701,289
Total Liabilities and Stockholders’ Equity	$ 43,950,411	$ 71,445,651