XML 33 R22.htm IDEA: XBRL DOCUMENT v3.8.0.1
Stock Based Compensation (Tables)
 9 Months Ended
Sep. 30, 2017
Stock Based Compensation [Abstract]  
Schedule of Total Stock-Based Compensation Expense from Stock Options and Warrants
The following table sets forth the total stock-based compensation expense resulting from stock options and warrants included in our Condensed Statements of Operations:
 
  
Three Months Ended September 30,
  
Nine Months Ended September 30,
 
  
2017
  
2016
  
2017
  
2016
 
Research and development — employee
 
$
(124,405
)
 
$
455,341
  
$
507,211
  
$
1,443,347
 
General and administrative — employee
  
479,330
   
586,315
   
1,348,815
   
3,742,733
 
Total employee stock-based compensation
 
$
354,925
  
$
1,041,656
  
$
1,856,026
  
$
5,186,080
 
                 
Research and development — non-employee
 
$
11,600
  
$
—
  
$
11,600
  
$
—
 
General and administrative — non-employee
  
32,581
   
(5,938
)
  
97,818
   
214,524
 
Total non-employee stock-based compensation
 
$
44,181
  
$
(5,938
)
 
$
109,418
  
$
214,524
 
Schedule of Share-based Payment Award, Fair Value of the Stock Options Granted, Assumptions
The fair value of the stock options was estimated using the Black-Scholes option-pricing model, based on the following assumptions:
 
  
Nine Months Ended September 30, 2017
  
Nine Months Ended September 30, 2016
 
Risk-free interest rate
  
2.32
%
  
1.72
%
Expected volatility
  
90.7
%
  
74.9
%
Expected lives (years)
 
6 to 10
   
6
 
Expected dividend yield
  
0.00
%
  
0.00
%
         
Schedule of Share-based Compensation, Stock Options, Activity
Presented below is our stock option activity:
 
  
Nine Months Ended September 30, 2017
 
  
Number of Options (Employees)
  
       Number of Options         (Non-Employees)
  
Total Number of Options
  
Weighted-Average  Exercise Price
 
Outstanding at January 1, 2017
  
2,813,295
   
100,000
   
2,913,295
  
$
14.22
 
Granted
  
31,667
   
3,334
   
35,001
  
$
3.96
 
Exercised, Forfeited or Expired
  
(412,645
)
  
—
   
(412,645
)
 
$
12.90
 
Outstanding at September 30, 2017
  
2,432,317
   
103,334
   
2,535,651
  
$
14.28
 
Options exercisable at September 30, 2017
  
1,956,450
   
103,334
   
2,059,784
  
$
16.02
 
Schedule of Share-based Compensation, Summarizes Significant Ranges of Outstanding Stock Options
The following table summarizes significant ranges of outstanding stock options under our plans at September 30, 2017:

Range of Exercise Prices
  
Total Number of Options
  
Weighted-Average Remaining Contractual Life (years)
  
Weighted-Average
Exercise Price
  
Total Number of Options Exercisable
  
Weighted-Average Remaining Contractual Life (years)
  
Weighted-Average
Exercise Price
 
$
2.46 - $9.00
   
635,787
   
9.23
  
$
2.70
   
328,075
   
9.26
  
$
2.76
 
$
9.06 – $15.00
   
1,266,229
   
7.05
  
$
13.50
   
1,099,463
   
6.89
  
$
13.38
 
$
15.06 – $24.00
   
158,207
   
6.45
  
$
17.28
   
156,818
   
6.44
  
$
17.22
 
$
24.06 –$195.30
   
475,428
   
5.49
  
$
30.90
   
475,428
   
5.49
  
$
30.90
 
     
2,535,651
   
7.26
  
$
14.28
   
2,059,784
   
6.91
  
$
16.02