The 2020 Equity Incentive Plan (the “2020 Plan”) was approved by the board of directors on September 24, 2020. The 2020 Plan provides for the grant of incentive stock options, non-qualified stock options, stock appreciation rights, restricted stock units, restricted stock awards, unrestricted stock awards, cash-based awards and dividend equivalent rights to the Company’s officers, employees, directors, and consultants. The number of shares of common stock initially reserved for issuance under the 2020 Plan is 4,406,374, which shall be increased, upon approval by the board of directors, on January 1, 2021 and each January 1 thereafter, in an amount equal to the least of (i) 4,406,374 shares of common stock, (ii) five percent (5%) of the outstanding common stock on the immediately preceding December 31, or (iii) such number of common stock determined by the board of directors no later than the immediately preceding December 31. For 2022, the board of directors exercised its discretion under clause (iii) to increase the number of shares of common stock reserved for issuance under the 2020 Plan by a lesser amount of 1,363,084 shares, effective as of January 1, 2022. As of June 30, 2022, there were 5,055,106 shares available for issuance under the 2020 Plan.

The 2020 Employee Stock Purchase Plan (the “2020 ESPP”) was approved by the board of directors on September 24, 2020. A total of 400,572 shares of common stock were initially reserved for issuance under this plan, which shall be increased, upon approval by the board of directors, on January 1, 2021 and each January 1 thereafter, to the lesser of (i) 801,504 shares of common stock, (ii) 1% of the outstanding shares of common stock on the last day of the immediately preceding fiscal year, or (iii) an amount determined by the board of directors or any of its committees no later than the last day of the immediately preceding fiscal year. For 2022, the board waived the increase to the shares reserved under the 2020 ESPP. On May 20, 2022, employees exercised their right to purchase 18,454 shares under the 2020 ESPP. As of June 30, 2022, 65,520 shares are issued or outstanding, and there were 801,464 shares available for issuance, under the 2020 ESPP.

The following table summarizes option activity for the six-month period ended June 30, 2022:


				Options Outstanding
									Weighted-
							Weighted		Average		Aggregate
	Shares						Average		Remaining		Intrinsic
	Available			Number of			Exercise		Contractual Life		Value
	for Grant			Options			Price		(in years)		(in 000s)
Balances at December 31, 2021		4,951,680			4,246,007		$	8.22		6.86	$	68,506
Shares reserved for issuance		1,363,084			—			—
Options granted		(1,267,997	)		1,267,997		$	16.33
Options forfeited / cancelled		8,339			(8,339	)	$	26.51
Options exercised		—			(170,472	)	$	1.06
Balances at June 30, 2022 (unaudited)		5,055,106			5,335,193		$	10.32		7.23	$	36,326
At June 30, 2022
Vested and expected to vest					5,353,193		$	10.32		7.23	$	36,326
Exercisable					3,009,863		$	5.85		5.92	$	30,124

At June 30, 2022, the total compensation cost related to nonvested awards not yet recognized is $25,298. The weighted-average period over which the nonvested awards is expected to be recognized is 3.2 years.

Expected Term: The Company uses the simplified method to calculate expected term described in the SEC’s Staff Accounting Bulletin No. 107, which takes into account vesting term and expiration date of the options.

Volatility: Volatility is based on an average of the historical volatilities of comparable publicly traded companies for the expected term.

Risk Free Interest Rate: The risk-free rate is based on the U.S. Treasury yields in effect at the time of grant for periods corresponding with the expected term of the option.

Dividend Yield: The Company has never declared or paid any cash dividends and does not plan to pay cash dividends in the foreseeable future, and therefore, used an expected dividend yield of zero in the valuation model.

Stock-based compensation expense recorded under ASC 718 related to stock options granted and common stock issued under the 2020 ESPP were allocated to research and development and general and administrative expense as follows:


	For the Three Months Ended				For the Six Months Ended
	June 30,		June 30,		June 30,		June 30,
	2022		2021		2022		2021
Research and development	$	807	$	282	$	1,456	$	533
General and administrative		1,711		868		3,239		1,244
Total stock-based compensation	$	2,518	$	1,150	$	4,695	$	1,777