Total share-based compensation related to stock options, common stock awards, warrants and JSOP awards was $147,228 and $388,925 during the three months ended March 31, 2015 and 2014, respectively.

Share-based compensation expense is classified in the condensed consolidated statements of comprehensive loss as follows:

Employee Stock Options

During the three months ended March 31, 2015 and 2014, no employees were granted stock options to purchase shares of common stock. During the three months ended March 31, 2014, a named executive of the Company exercised 1,984,080 stock options. Cash received from stock option exercise was $101,933. There were no other employee stock option exercises during the three months ended March 31, 2015 or 2014. The Company recognized $63,634 and $13,073 of compensation expense related to employee stock options during the three months ended March 31, 2015 and 2014, respectively.

Non-Employee Stock Options

No non-employee stock options were granted during the three months ended March 31, 2015 or 2014 and no non-employee stock options were exercised during the three months ended March 31, 2015 or 2014. The Company recognized $4,438 and $5,447 of compensation expense related to non-employee stock options during the three months ended March 31, 2015 and 2014, respectively.

Common Stock Awards

During the three months ended March 31, 2015 and 2014, the Company granted 104,957 and 36,905 common stock awards, respectively, based on the value of the services provided and the average stock price during each respective quarter. As all services were rendered in each respective quarter, $25,500 of compensation expense related to common stock awards was recognized during each of the three month periods ended March 31, 2015 and 2014, respectively. All common stock awards were authorized but not issued as of March 31, 2015.

Warrants

In connection with the Company’s collaboration agreements, the Company issued warrants to purchase 10,425,000 shares of common stock to its collaborative partners on December 31, 2014. A warrant to purchase 1,600,000 shares of common stock was also issued to a non-employee director for consulting services provided to the Company on December 31, 2014. These warrants were fair valued at issuance date using the Black-Scholes option pricing model. The warrants are subject to re-measurement at each reporting period until the measurement date is reached. Expense is recognized on a straight-line basis over the expected service period or at the date of issuance, if there is not a service period. No warrants to purchase common stock were issued during the three months ended March 31, 2015.

Joint Share Ownership Plan

In 2010 and 2012, the Company issued 1,701,913 and 8,986,281 JSOP awards, respectively, to two senior executives under the JSOP. During 2011, the 2010 JSOP awards fully vested under the terms of the JSOP due to a significant change in beneficial ownership of the Company and the related compensation charges were fully recorded during periods prior to 2014 related to this accelerated vesting. During the first quarter of 2014, the 2012 JSOP awards fully vested under the terms of the JSOP due the achievement of specific share price hurdles and the related compensation charges were fully recorded during the first quarter of 2014 related to this accelerated vesting. As of March 31, 2015, all JSOP awards were fully vested.

The total fair value of the 2012 JSOP awards was $853,889 at the date of issuance. The Company recognized zero and $344,905 of compensation costs during the three months ended March 31, 2015 and 2014, respectively, related to the 2012 JSOP awards.