Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2016

Disclosure of Share-based Compensation Arrangements by Share-based Payment Award

A summary of the Company’s option activity and related information for the nine-month period ended September 30, 2016 is as follows:

	Number of Shares		Weighted Average Exercise Price		Total Intrinsic Value
Outstanding as of December 31, 2015		3,367,784	$	7.16	$	3,971,205
Granted		1,058,000		7.07		430,650
Forfeited		(48,583)		10.15		-
Outstanding as of September 30, 2016		4,377,201	$	7.10	$	3,554,711
Options vested and exercisable		2,921,597	$	6.69	$	2,714,765

Assumptions for Weighted Average Fair Value of Options Granted

The fair value of the options granted for the nine months ended September 30, 2016 and 2015, were based on the following assumptions:

	Nine Months Ended September 30,
	2016	2015
Exercise price	$5.84 - $8.14	$9.42 - $16.55
Expected stock price volatility	86.5% - 91.8%	89.18% - 95.55%
Risk-free rate of interest	1.36% - 1.94%	1.49% - 2.08%
Term (years)	5.37 - 7.00	5.13 - 6.97

Estimated Future Stock Based Expenses Relating to Unvested Stock Options

Estimated future stock-based compensation expense relating to unvested stock options is as follows:

	Future Stock Option Compensation Expenses
Three months ended December 31, 2016	$	1,117,796
Year ended December 31, 2017		2,722,769
Year ended December 31, 2018		1,233,560
Year ended December 31, 2019		488,828
Year ended December 31, 2020		100,085
Total	$	5,663,038

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

Stock-based compensation expense for the three and nine months ended September 30, 2016 and 2015 is as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Research and development	$	772,835	$	148,963	$	2,341,842	$	2,624,265
General and administrative		282,208		1,000,466		1,691,194		3,731,188
Total stock-based compensation expense	$	1,055,043	$	1,149,429	$	4,033,036	$	6,355,453