STOCK OPTIONS, RESTRICTED STOCK AND WARRANTS | 10 - STOCK OPTIONS, RESTRICTED STOCK AND WARRANTS Stock Options On July 31, 2014, the Company’s Board of Directors adopted, and the Company’s stockholders approved, the 2014 Equity Incentive Plan (the “2014 Plan”), which reserves a total of 8,100,000 shares of the Company’s common stock for incentive awards. Generally, shares that are expired, terminated, surrendered or cancelled without having been fully exercised will be available for future awards. As of September 30, 2017, there were 1,311,042 shares available for issuance under the 2014 Plan to eligible employees, non-employee directors and consultants. This number is subject to adjustment in the event of a stock split, reverse stock split, stock dividend, or other changes in the Company’s capitalization. During the nine months ended September 30, 2017 and 2016, there were 308,333 and 4,068,182 stock options granted to employees, directors or consultants with weighted-average grant date fair values, using the Black-Scholes pricing model, of $0.12 and $0.16, respectively. The Company estimates the fair value of each stock award on the grant date using the Black-Scholes option-pricing model based on the following assumptions and the assumptions regarding the fair value of the underlying common stock on each measurement date: For the nine months ended September 30, 2017 Expected Volatility 115% - 116% Risk-free interest rate 1.93% - 2.09% Expected term (in years) 5.0 - 6.0 Expected dividend yield 0% Stock-based compensation expense for stock options was $33,149 and $260,343 for the three months ended September 30, 2017 and 2016, respectively. Stock-based compensation expense for stock options was $177,150 and $803,747 for the nine months ended September 30, 2017 and 2016, respectively. The Company has an aggregate of $105,350 of unrecognized stock-based compensation expense for stock options as of September 30, 2017 to be amortized over a weighted average period of 1.0 years. In connection with Wael Fayad’s appointment as the Company’s Chairman, Chief Executive Officer and President in September 2016, the Company granted Mr. Fayad 1,750,000 options to purchase the Company’s common stock outside of the 2014 Plan, and 850,000 options to purchase the Company’s common stock under the 2014 Plan. On June 29, 2017, Mr. Fayad resigned as the Company’s President and Chief Executive Officer. Mr. Fayad remains on the Company’s Board of Directors and continues to serve as Chairman of the Board. Mr. Fayad’s options to purchase shares of the Company’s common stock remain outstanding while he continues to serve on the Company’s Board of Directors. On June 9, 2017, the Company entered into an amendment (the “Tinkelenberg Amendment”) to that certain separation letter agreement (the “Separation Agreement”), dated as of August 4, 2016, by and between the Company and Arthur H. Tinkelenberg, Ph.D., the Company’s former President and Chief Executive Officer. Pursuant to the terms of the Separation Agreement, the Company had agreed, among other things, to make certain payments to Dr. Tinkelenberg in connection with his separation of employment from the Company. Pursuant to the terms of the Tinkelenberg Amendment, Dr. Tinkelenberg agreed to forego the remaining amounts of the severance payments due to him under the Separation Agreement, effective as of June 1, 2017. In addition, the Company agreed that all remaining unvested options to purchase shares of the Company’s common stock held by Dr. Tinkelenberg fully vest and become exercisable as of June 1, 2017. The Company’s stock-based compensation expense includes $55,929 recorded during the nine months ended September 30, 2017 as a result of the accelerated vesting of Dr. Tinkelenberg’s common stock options. A summary of aggregate stock option activity both under the 2014 Plan and outside of the 2014 Plan for the nine months ended September 30, 2017 is as follows: Weighted- Weighted- Average Average Remaining Exercise Contractual Shares Price Term (years) Outstanding as of December 31, 2016 7,670,823 $ 0.41 8.8 Granted 308,333 $ 0.15 Canceled (422,023 ) $ 0.26 Outstanding as of September 30, 2017 7,557,133 $ 0.40 7.8 Exercisable as of September 30, 2017 4,837,885 $ 0.49 7.7 The aggregate intrinsic value of stock options exercisable as of September 30, 2017 was $0. The aggregate intrinsic value was calculated as the difference between the exercise price of the stock options and the fair value of the underlying common stock as of the unaudited condensed consolidated balance sheet date. Restricted Stock Stock-based compensation expense for restricted stock awards was $2,495 and $20,633 for the three months ended September 30, 2017 and 2016, respectively. Stock-based compensation expense for restricted stock awards was $9,980 and $79,551 for the nine months ended September 30, 2017 and 2016, respectively. A summary of restricted stock activity for the nine months ended September 30, 2017 is as follows: Weighted- Number of Average Grant Shares Date Fair Value Balance of unvested restricted stock as of December 31, 2016 — Issuance of restricted stock 66,666 $ 0.15 Vested (50,000 ) $ 0.15 Balance of unvested restricted stock as of September 30, 2017 16,666 $ 0.15 The Company has a de minimis Warrants A summary of the warrants outstanding as of September 30, 2017 is as follows: Warrant Type Warrants Exercise Price PPO 13,686,510 $ 2.00 PPO Agent 2,000,000 $ 0.125 Enumeral Series B Financing 421,969 $ 0.726 Enumeral 2014 Convertible Promissory Note Financing 510,236 $ 0.245 2016 Placement Agent 4,880,655 $ 0.0625 2017 Unit Offering 7,682,000 $ 0.10 2017 Unit Offering Agent 768,200 $ 0.05 Total 29,949,570 Warrant Issuance Transactions On July 29, 2016, the Company entered into a Subscription Agreement with certain accredited investors (the “Buyers”), pursuant to which the Buyers purchased the Company’s 12% Senior Secured Promissory Notes (the “2016 Notes”) in the aggregate principal amount of $3,038,256 (the “2016 Note Offering”). On December 12, 2016, the Company consummated an offer to amend and exercise certain outstanding warrants to purchase an aggregate of 21,549,510 shares of its common stock originally issued to investors who participated in the Company’s July 31, 2014 private placement financing (the “Warrant Tender Offer”). Pursuant to the Warrant Tender Offer, an aggregate of 6,863,000 warrants were tendered by their holders, and the Company received gross proceeds in the amount of $3,431,500 for the issuance of 27,452,000 shares of the Company’s common stock. In addition, pursuant to the Warrant Tender Offer, the full principal balance and accrued interest of the 2016 Notes was converted into 48,806,545 shares of the Company’s common stock. In connection with the conversion of the 2016 Notes and pursuant to the terms of the placement agent agreement associated with the 2016 Notes, the Company issued warrants to purchase 4,880,655 shares of the Company’s common stock at an exercise price of $0.125 per share to designees of the placement agent (the “2016 Placement Agent Warrants”). On March 21, 2017, the Company entered into an amendment with the holders of the 2016 Placement Agent Warrants to reduce the exercise price of such warrants from $0.125 per share to $0.0625 per share in consideration of the past efforts as well as future support and cooperation of the agent and its designees on behalf of the Company. The estimated fair value of these warrants at the time of the amendment was determined to be $601,144 using the Black-Sholes pricing model and the following assumptions: expected term of 9.7 years, exercise price of $0.0625 per share, 126.0% volatility, a risk-free rate of 2.43%, and no expected dividends. The Company recorded expense of $8,276 as a result of this amendment. In connection with the 2017 Unit Offering, the Company issued warrants to purchase 7,682,000 shares of the Company’s common stock to the Buyers (the “Investor Warrants”). The estimated fair value of these warrants at the time of issuance was determined to be $773,252 using the Black-Sholes pricing model and the following assumptions: expected term of 5.0 years, exercise price of $0.10 per share, 118.5% volatility, a risk-free rate of 1.79%, and no expected dividends. The value of the Investor Warrants exceeded the net proceeds from the 2017 Unit Offering and were recorded at the maximum value available after allocation of the beneficial conversion feature. See Note 7, 2017 Unit Offering. Pursuant to the terms of a Placement Agency Agreement (the “Placement Agency Agreement”), dated as of May 12, 2017, between the Company and the placement agents for the Offering (the “Placement Agents”), the Placement Agents are paid a commission equal to ten percent (10%) of the gross proceeds at each closing of the Offering (the “Placement Agent Cash Fee”). The Placement Agency Agreement also provides that the Placement Agents, or their designees, will receive five-year warrants (the “Placement Agent Warrants”) to purchase a number of shares of Common Stock at an exercise price of $0.05 per share equal to 10% of the number of Conversion Shares issuable upon conversion of the 2017 Notes issues at each closing of the Offering, based on a conversion price of $0.10 per share. In accordance with the terms of the Placement Agency Agreement, on the Closing Date the Company issued Placement Agent Warrants to purchase an aggregate of 768,200 shares of Common Stock on the terms set forth above to the Placement Agents. The estimated fair value of these warrants at the time of issuance was determined to be $82,065 using the Black-Sholes pricing model and the following assumptions: expected term of 5.0 years, exercise price of $0.05 per share, 118.5% volatility, a risk-free rate of 1.79%, and no expected dividends. In September 2017, one of the Company’s warrant holders abandoned all of its warrants to purchase shares of the Company’s common stock and returned those warrants to the Company. The abandoned warrants consist of warrants to purchase (a) 1,000,000 shares of the Company’s common stock at a price of $2.00 per share, expiring on July 30, 2019, and (b) 255,120 shares of the Company’s common stock at an exercise price of $0.2451, expiring on February 2, 2024. Derivative Liability Warrants (Amended in connection with the Warrant Tender Offer) PPO and PPO Agent Warrants In July 2014, the Company issued warrants to purchase 23,549,510 shares of the Company’s common stock in connection with the Company’s private placement offering that closed on July 31, 2014 (the “PPO”), of which warrants to purchase 21,549,510 shares of the Company’s common stock had an exercise price of $2.00 per share and were issued to the investors in the PPO, and warrants to purchase 2,000,000 shares of the Company’s common stock had an exercise price of $1.00 per share and were issued to the placement agents for the PPO (or their affiliates). Due to a price protection provision included in the warrant agreements, the warrants were deemed to be and were recorded as a derivative liability. As such, these outstanding warrants were revalued each reporting period with the resulting gains and losses recorded as the change in fair value of derivative liabilities on the unaudited condensed consolidated statement of operations. Derivative Liability Re-Measurement The Company used the Black-Scholes option-pricing model to estimate the fair values of the issued and outstanding warrants during the nine months ended September 30, 2016. The Company recorded income of $409,891 and $1,232,425 for the three and nine months ended September 30, 2016 due to the change in the fair value of the warrants for those periods. Outstanding warrants were revalued each reporting period with the resulting gains and losses recorded as the change in fair value of derivative liabilities on the unaudited condensed consolidated statements of operations. Due to the removal of the anti-dilution provisions in connection with the Warrant Tender Offer, the derivative liabilities were re-valued on December 12, 2016 and any remaining value was reclassified to equity upon extinguishment of the derivative liabilities. |