The Company maintains four equity compensation plans; the Orchard Therapeutics Limited Employee Share Option Plan with Non-Employee Sub-Plan and U.S. Sub-Plan (the “2016 Plan”), the Orchard Therapeutics plc 2018 Share Option and Incentive Plan (the “2018 Plan”), the 2018 Employee Share Purchase Plan (the “ESPP”), and the 2020 Inducement Equity Plan (the “Inducement Plan”). The board of directors has determined not to make any further awards under the 2016 plan. As of December 31, 2022, there were 5,341,768 shares available for grant under the 2018 Plan, 721,500 available for grant under the Inducement Plan, and 627,677 shares available for grant under the ESPP.

The numbers of options and restricted stock units, the weighted average grant date fair values per stock option and per share, and the weighted average exercise prices are all shown below on a per ordinary share basis. Effective March 10, 2023, The Company’s ADSs that are listed on the NASDAQ Capital Market each represent ten ordinary shares.

On October 4, 2022, the Company’s Compensation Committee approved a one-time stock option repricing for certain previously granted and still outstanding options held by the Company’s employees and certain independent contractors which had an exercise price above $1.25. As a result of the repricing, the exercise price for 7,946,139 vested and unvested options outstanding was lowered to $0.58. No other terms of the repriced options were modified and the repriced stock will continue to vest according to their original vesting schedules and will retain their original expiration dates. The repricing resulted in one-time stock-based compensation expense of $0.9 million related to vested options and incremental stock option expense of $0.8 million related to unvested options which will be amortized on a straight-line basis over the remaining vesting period of those options.

The fair value of each stock option award is estimated on the date of grant using the Black-Scholes option-pricing model using the range of assumptions for the years ended December 31, 2022 and 2021, as noted in the following table:


	Year Ended December 31,
	2022	2021
Risk-free interest rate	1.5% - 4.4%	0.5% - 1.3%
Expected term (in years)	2.0 - 6.1	5.3 - 6.1
Expected volatility	74.4% - 79.5%	74.2% - 78.7%
Expected dividend rate	0.0%	0.0%

The following table summarizes option activity under the plans for the year ended December 31, 2022:


	Shares			Weighted Average Exercise Price per Share		Weighted Average Remaining Contractual Life (Years)		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2021		17,300,740		$	6.57
Granted		4,600,154			0.56
Exercised		(699,234	)		-
Forfeited		(4,777,493	)		6.81
Outstanding at December 31, 2022		16,424,167		$	1.56		7.38	$	-
Vested and expected to vest at December 31, 2022		16,424,167		$	1.56		7.38	$	-
Exercisable at of December 31, 2022		9,212,552		$	2.28		6.26	$	-

The aggregate intrinsic value of options is calculated as the difference between the exercise price of the options and the fair value of the Company’s ordinary shares for those options that had exercise prices lower than the fair value of the Company’s ordinary shares. During the years ended December 31, 2022 and 2021, the total intrinsic value of share options exercised was $0.4 million and $7.4 million, respectively. The weighted average grant date fair value per share of options granted during the years ended December 31, 2022 and 2021, was $0.32 and $3.10, respectively.

The Company granted 195,000 performance based RSUs with a total grant date fair value of $1.4 million to its Chief Executive Officer, Bobby Gaspar, M.D., Ph.D., in April 2020. The award vests on January 2, 2024 as to 1/3 of the award for each of the first three to occur of four milestones, if each such milestone is achieved by the Company on or before December 31, 2023 and Dr. Gaspar remains continuously employed with the Company through January 2, 2024. The milestones relate to the achievement of specific clinical and regulatory milestones. No performance-based share unit performance conditions associated with the CEO award were deemed probable and none vested during the year ended December 31, 2022.

Time-based restricted share units vest in equal annual installments over a three-year period.

The following table summarizes restricted share unit award activity for the year-end December 31, 2022:


	Performance-based RSUs		Time-based RSUs			Total RSUs			Weighted Average Grant Date Fair Value per Share
Unvested at December 31, 2021		195,000		123,333			318,333		$	6.41
Granted		—		2,192,988			2,192,988			0.46
Vested		—		(55,001	)		(55,001	)		5.58
Forfeited		—		(392,444	)		(392,444	)		0.60
Unvested at December 31, 2022		195,000		1,868,876			2,063,876		$	0.55

During the years ended December 31, 2022 and 2021, the total fair value of time-based RSU’s that vested was $0.3 million and $0.3 million, respectively.

Share-based compensation expense related to share options, restricted share unit awards, and the employee stock purchase plan was classified in the consolidated statements of operations and comprehensive loss as follows (in thousands):


	Year Ended December 31,
	2022		2021
Research and development	$	6,791	$	9,214
Selling, general and administrative		9,219		13,322
Total	$	16,010	$	22,536

Total share-based compensation by award type was as follows (in thousands):


	Year Ended December 31,
	2022		2021
Restricted share units	$	838	$	550
Share options		15,172		21,986
Total	$	16,010	$	22,536

As of December 31, 2022, total unrecognized compensation cost related to options was $14.0 million. This amount is expected to be recognized over a weighted average period of 2.34 years. As of December 31, 2022, total unrecognized compensation cost related to time-based RSUs was $0.8 million. This amount is expected to be recognized over a weighted average period of 1.96 years. As of December 31, 2022, the total unrecognized compensation cost related to performance-based RSUs is a maximum of $1.4 million, the timing of recognition will be dependent upon achievement of milestones.