CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 6,657,158	$ 8,225,764
Accounts receivable and unbilled receivable	114,343	77,095
Prepaid expenses and other current assets	1,068,144	1,165,828
Total current assets	7,839,645	9,468,687
Property and equipment, net	2,223,597	2,426,312
Other assets	345,277	389,942
Total Assets	10,408,519	12,284,941
Current liabilities:
Accounts payable	651,671	825,244
Accrued expenses	1,685,178	1,454,587
Deferred rent	341,924	334,424
Current portion of long-term debt	1,174,989	1,331,515
Total current liabilities	3,853,762	3,945,770
Derivative financial instruments—warrants	779,076	649,387
Deferred rent, net of current portion	1,096,591	1,183,677
Total Liabilities	5,729,429	5,778,834
Commitments and contingencies (Note 9)
Stockholders’ equity
Preferred stock, $0.001 par value, 20,000,000 shares authorized; 60,600 shares outstanding at March 31, 2018 and December 31, 2017; designated as Series A Convertible Preferred Stock with liquidation preference of $606,000 at March 31, 2018 and December 31, 2017	60	60
Common stock, $0.0001 par value, 150,000,000 shares authorized; 58,832,953 and 52,791,584 shares issued and outstanding at March 31, 2018 and December 31, 2017, respectively	5,883	5,279
Additional paid-in capital	182,401,648	179,546,954
Accumulated deficit	(177,728,501)	(173,046,186)
Total Stockholders’ Equity	4,679,090	6,506,107
Total Liabilities and Stockholders’ Equity	$ 10,408,519	$ 12,284,941

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.