On May 15, 2018, the Company’s Board of Directors authorized and approved the adoption of the 2018 Omnibus Incentive Plan (as amended, the “2018 Plan”), which was effective upon approval by the stockholders of the Company on June 28, 2018 and under which an aggregate of 153,031 shares may be issued. This share reserve is the sum of 85,714 new shares, plus the remaining 67,317 shares that remained available for issuance under the Company’s 2016 Omnibus Incentive Plan, the predecessor incentive plan (the “2016 Plan”) at the time of the adoption of the 2018 Plan. Pursuant to the terms of the 2018 Plan, the Company is authorized to grant stock options, as well as awards of stock appreciation rights, restricted stock, unrestricted shares, restricted stock units (“RSUs”), stock equivalent units and performance-based cash awards. These awards may be granted to directors, officers, employees and eligible consultants. Vesting and the term of an option is determined at the discretion of the Company’s Board of Directors. Subsequent to the adoption of the 2018 Plan, the Company ceased granting awards under the 2016 Plan, the predecessor incentive plan. However, outstanding stock options granted prior to the effective date of the 2018 Plan are still governed by the 2016 Plan or the Company’s 2014 Stock Incentive Plan, which preceded the 2016 Plan.

As of December 31, 2020, there were an aggregate of 94,485 shares of common stock remaining available for issuance under the 2018 Plan.

For the year ended December 31, 2020, the Company issued 42,417 stock options to employees and directors of which 3,425 were forfeited. The Company issued 571 stock options to consultants during the same period.

The following is a summary of stock option activity for the year ended December 31, 2020 and 2019:

				Weighted Average
				Remaining		Weighted Average		Aggregate
				Contractual		Exercise Price		Intrinsic Value
	Number of Options			Life (in years)		in USD$		in USD$
Outstanding as of December 31, 2018		94,475			5.16	$	249.87	$	8,308
Granted		33,337					162.74
Forfeited		(13,939	)				298.55
Exercised ⁽¹⁾		(14,855	)				96.95
Outstanding as of December 31, 2019		99,018			7.78	$	236.63	$	—
Granted		42,988				$	15.20
Forfeited/Cancelled		(28,448	)				210.57
Exercised		—					—
Outstanding as of December 31, 2020		113,558			7.75	$	159.33	$	—
Exercisable as of December 31, 2020		57,725			6.56	$	117.90	$	—

(1) For the year ended December 31, 2019, 14,855 stock options were exercised on a cashless basis resulting in 13,818 shares being withheld in satisfaction of the exercise price.

As of December 31, 2020, the unrecognized compensation cost related to non-vested stock options outstanding for employees and directors was $2.4 million which will be recognized over a weighted-average remaining vesting period of approximately 2.3 years. Compensation cost is not adjusted for estimated forfeitures, but instead is adjusted upon an actual forfeiture of a stock option.

For the years ended December 31, 2020 and 2019, the Company granted 42,417 and 33,337 stock options, respectively, to employees and directors at a weighted average exercise price of $15.23 and $162.74, respectively. The fair value of employee and director stock options granted for the years ended December 31, 2020 and 2019 had a weighted average grant date fair value of $9.71 and $105.38 per option, respectively, and they were estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions:

	Year Ended December 31,
	2020			2019
Stock price	$15.23			$162.74
Exercise price	$15.23			$162.74
Expected term	5.32 years			5.42 years
Expected volatility		75.35	%		76.90	%
Risk-free interest rate		0.52	%		1.96	%
Dividend rate		0.00	%		0.00	%

For the year ended December 31, 2020, the Company granted 571 stock options to consultants at a weighted average exercise price of $13.58. Stock options granted to the Company’s consultants for the year ended December 31, 2020 had a weighted average grant date fair value of $8.18 per share, and they were estimated using the Black-Scholes option-pricing model with the following weighted-average assumptions:

For the year ended December 31, 2019 the Company did not grant any stock options to consultants. As of December 31, 2020, the unrecognized compensation cost related to non-vested stock options outstanding for consultants was $39 thousand which will be recognized over a weighted-average remaining vesting period of 0.8 years.

Beginning in the fourth quarter of 2019, certain members of the Company’s executive management team elected to receive RSUs in lieu of cash compensation under the 2018 Plan that vested upon issuance. The fair value of the RSUs is based on the closing price of the Company’s common stock on the day of the grant.

The following is a summary of the Company’s RSU activity for the years ended December 31, 2020 and 2019:

	Number of Restricted Stock Units			Weighted Average Grant Date Fair Value per Unit
Outstanding as of December 31, 2018		27		CAD$350.00
Granted		788		USD$21.17
Vested and settled during 2019 ⁽¹⁾		(27	)	CAD$350.00
Outstanding as of December 31, 2019		788		USD$21.17
Granted		7,172		USD$15.25
Settled during 2020		(7,792	)	USD$17.81
Outstanding as of December 31, 2020		168		USD$13.20

(1) Includes 7 RSUs withheld to satisfy required withholding taxes.

Stock-based compensation expense is classified in the Company’s consolidated statements of operations and comprehensive loss as follows (amounts in thousands):