CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 15,065,913	$ 8,225,764
Accounts receivable and unbilled receivable	128,577	77,095
Prepaid expenses and other current assets	849,082	1,165,828
Total current assets	16,043,572	9,468,687
Property and equipment, net	1,627,605	2,426,312
Other assets	249,645	389,942
Total Assets	17,920,822	12,284,941
Current liabilities:
Accounts payable	476,300	825,244
Accrued expenses	1,718,060	1,454,587
Deferred rent, current portion	472,251	334,424
Current portion of long-term debt	0	1,331,515
Total current liabilities	2,666,611	3,945,770
Derivative financial instruments—warrants	70,347	649,387
Deferred rent, net of current portion	1,204,109	1,183,677
Total Liabilities	3,941,067	5,778,834
Commitments and contingencies (Note 8)
Stockholders’ equity
Preferred stock, $0.001 par value, 20,000,000 shares authorized; 277,100 designated as Series A Convertible Preferred Stock; 60,600 shares outstanding at September 30, 2018 and December 31, 2017 with liquidation preference of $606,000 at September 30, 2018 and December 31, 2017; 8,860 designated as Series B Convertible Preferred Stock; 0 shares outstanding at September 30, 2018 and December 31, 2017, respectively	60	60
Common stock, $0.0001 par value, 150,000,000 shares authorized; 22,957,192 and 4,399,299 shares issued and outstanding at September 30, 2018 and December 31, 2017, respectively	7,738	5,279
Additional paid-in capital	201,998,634	179,546,954
Accumulated deficit	(188,026,677)	(173,046,186)
Total stockholders’ equity	13,979,755	6,506,107
Total liabilities and stockholders’ equity	$ 17,920,822	$ 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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Data Type:	xbrli:monetaryItemType
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.