The Company’s stock option awards generally vest over four years and typically have a contractual life of ten years. At September 30, 2019, there was $1,536,208 of unrecognized compensation cost related to stock options, which is expected to be recognized over a weighted-average period of 3.41 years. During the nine months ended September 30, 2019, the Company granted 725,000 stock options with a weighted average exercise price of $2.67 and per share weighted average grant date fair value of $2.02.

Information related to stock options outstanding at September 30, 2019 is as follows:

	Number of Stock Options		Weighted- average Exercise Price		Weighted- average Remaining Contractual Term (Years)		Aggregate Intrinsic Value
Outstanding		976,861	$	5.16		5.91	$	—
Exercisable		188,928	$	11.88		5.19	$	—
Unvested		787,933	$	3.55		6.08	$	—

At September 30, 2019, the Company had unvested restricted stock of 323,191 shares with total unrecognized compensation expense of $917,158, which the Company expects to recognize over a weighted average period of approximately 3.17 years. During the nine months ended September 30, 2019, the Company released 214 shares of common stock from restriction as a result of the vesting of restricted stock.

On March 29, 2019, the board of directors adopted the 2019 Employee Stock Purchase Plan (the “2019 ESPP”). A total of 403,500 shares of the Company’s common stock have been reserved for issuance under the 2019 ESPP. Subject to any plan limitations, the 2019 ESPP allows eligible employees to contribute through payroll deductions up to 10% of their earnings for the purchase of the Company’s common stock at a discounted price per share. The offering periods begin in February and August of each year, with the initial offering period starting on August 1, 2019. The common shares issuable under the 2019 ESPP were registered pursuant to a registration statement on Form S-8 on April 4, 2019

Unless otherwise determined by the administrator, the Company’s common stock will be purchased for the accounts of employees participating in the 2019 ESPP at a price per share that is the lesser of 85% of the fair market value of the Company’s common stock on the first trading day of the offering period or 85% of the fair market value of the Company’s common stock on the last trading day of the offering period. The ESPP estimated shares to be purchased fair value is included in the stock-based compensation expense.

Employees have the ability to purchase shares of the Company’s common stock at the lower of the first or last trading day of the offering period, which represents an option and, therefore, the ESPP is a compensatory plan under ASC 718-50, Employee Stock Purchase Plans. Accordingly, stock-based compensation expense is determined based on the option’s grant-date fair value and is recognized over the requisite service period of the option. The Company used the Black-Scholes valuation model and recognized stock-based compensation expense of $8,596 for the three and nine months ended September 30, 2019, respectively.

Stock-based compensation expense is classified in the unaudited consolidated statements of operations and comprehensive loss for the three and nine months ended September 30, 2019 and 2018 as follows:

	For the Three Months Ended September 30,				For the Nine Months Ended September 30,
	2019		2018		2019		2018
Research and development	$	71,662	$	39,405	$	240,345	$	236,717
General and administrative		216,113		56,186		744,915		467,708
Total	$	287,775	$	95,591	$	985,260	$	704,425