| Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] |
The following table summarizes amounts charged to expense for stock-based compensation related to employee and director stock option grants and stock-based compensation recorded in connection with stock options granted to non-employee consultants:
| |
|
Three Months Ended
June 30, |
|
|
Six Months Ended
June 30, |
|
|
Cumulative
Development
Stage Period
from
November 7,
2002 through
June 30, |
|
| |
|
2012 |
|
|
2011 |
|
|
2012 |
|
|
2011 |
|
|
2012 |
|
| Employee and director stock option grants: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Research and development |
|
$ |
78,145 |
|
|
$ |
31,465 |
|
|
$ |
156,189 |
|
|
$ |
54,991 |
|
|
$ |
644,747 |
|
| General and administrative |
|
|
249,278 |
|
|
|
101,519 |
|
|
|
498,246 |
|
|
|
136,455 |
|
|
|
2,646,433 |
|
| |
|
|
327,423 |
|
|
|
132,984 |
|
|
|
654,435 |
|
|
|
191,446 |
|
|
|
3,291,180 |
|
| Non-employee consultant stock option grants: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Research and development |
|
|
34,355 |
|
|
|
17,287 |
|
|
|
81,369 |
|
|
|
17,287 |
|
|
|
117,526 |
|
| General and administrative |
|
|
44,344 |
|
|
|
48,853 |
|
|
|
87,671 |
|
|
|
48,853 |
|
|
|
269,642 |
|
| |
|
|
78,699 |
|
|
|
66,140 |
|
|
|
169,040 |
|
|
|
66,140 |
|
|
|
387,168 |
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total stock-based compensation |
|
$ |
406,122 |
|
|
$ |
199,124 |
|
|
$ |
823,475 |
|
|
$ |
257,586 |
|
|
$ |
3,678,348 |
|
|
| Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] |
The following table summarizes weighted-average values and assumptions used for options granted to employees, directors and consultants in the periods indicated:
| |
|
Three and Six
Months Ended
June 30, 2011 |
|
| Volatility |
|
|
110 |
% |
| Risk-free interest rate |
|
|
1.84% – 3.17 |
% |
| Expected life (years) |
|
|
5.5 – 6.25 |
|
| Dividend |
|
|
0 |
% |
| Weighted-average exercise price |
|
$ |
1.45 |
|
| Weighted-average grant-date fair value |
|
$ |
1.22 |
|
|
| Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] |
A summary of stock option activity under stock option plans is as follows:
| |
|
Number of
Shares
Issuable Upon
Exercise of
Outstanding
Options |
|
|
Weighted
Average
Exercise Price |
|
|
Weighted
Average
Remaining
Contracted
Term in
Years |
|
|
Aggregate
Intrinsic
Value |
|
| Outstanding at December 31, 2011 |
|
|
4,827,638 |
|
|
$ |
1.82 |
|
|
|
|
|
|
|
|
|
| Granted |
|
|
— |
|
|
|
|
|
|
|
|
|
|
|
|
|
| Canceled |
|
|
— |
|
|
|
|
|
|
|
|
|
|
|
|
|
| Outstanding at March 31, 2012 |
|
|
4,827,638 |
|
|
$ |
1.82 |
|
|
|
|
|
|
|
|
|
| Granted |
|
|
— |
|
|
|
|
|
|
|
|
|
|
|
|
|
| Canceled |
|
|
— |
|
|
|
|
|
|
|
|
|
|
|
|
|
| Outstanding at June 30, 2012 |
|
|
4,827,638 |
|
|
$ |
1.82 |
|
|
|
|
|
|
|
|
|
| Vested, June 30, 2012 |
|
|
1,555,462 |
|
|
$ |
3.37 |
|
|
|
8.91 |
|
|
$ |
212,560 |
|
| Unvested, June 30, 2012 |
|
|
3,272,176 |
|
|
$ |
1.09 |
|
|
|
9.10 |
|
|
$ |
877,714 |
|
| Exercisable at June 30, 2012 |
|
|
1,555,462 |
|
|
$ |
3.37 |
|
|
|
8.91 |
|
|
$ |
212,560 |
|