Stock-Based Compensation (Tables)

6 Months Ended

Jun. 30, 2017

Stock-Based Compensation [Abstract]

Weighted-Average Valuation Assumptions, Stock Option Grants

The assumptions used in the Black-Scholes option pricing model are presented below:

	Six Months Ended June 30,
	2017		2016
Risk-free interest rate	1.27 to 2.27	%	1.46 to 1.63	%
Expected volatility	117 to 131	%	113 to 115	%
Expected term (years)	2.0 to 9.6		6.0
Expected dividend yield	0	%	0	%

Allocation of Stock-Based Compensation Expenses

The table below summarizes the total stock-based compensation expense included in the Company’s consolidated statements of operations for the periods presented:

	Three Months Ended June 30,				Six Months Ended June 30,
	2017		2016		2017		2016
Research and development	$	73,000	$	26,000	$	101,000	$	52,000
General and administrative		226,000		522,000		369,000		1,312,000
Total stock-based compensation	$	299,000	$	548,000	$	470,000	$	1,364,000

Summary of Stock Option Activity

Stock option transactions during the six months ended June 30, 2017 are presented below:

	Options Outstanding
					Average
			Weighted		Remaining
			Average		Contractual
			Exercise		Term		Intrinsic
	Shares		Price		(Years)		Value
Balance, December 31, 2016		74,890	$	64.50		8.65	$	-
Granted		239,083		2.29		-
Exercised		-		-		-
Forfeited/Cancelled		(28,697)		89.66		-
Balance, June 30, 2017		285,276	$	9.83		7.20	$	5,932
Exercisable at June 30, 2017		78,522	$	20.12		4.96	$	-

Shares Reserved for Future Issuance

As of June 30, 2017, the Company had reserved shares of its common stock for future issuance as follows:

	Shares Reserved
Stock options outstanding		285,276
Employee stock purchase plan		21,016
Available for future grants under the 2016 Plan		36,069
Warrants		8,976,167
Total shares reserved		9,318,528