XML 28 R16.htm IDEA: XBRL DOCUMENT v3.24.2.u1
Stock Based Compensation
 6 Months Ended
Jun. 30, 2024
Share-Based Payment Arrangement [Abstract]  
Stock Based Compensation Stock Based Compensation
The Company has a 2013 Stock Option Plan (the “2013 Plan”), which is administered by the Compensation Committee of the Company’s board of directors. Under the 2013 Plan, stock options to purchase shares of common stock could be granted to eligible employees, officers, directors and consultants of the Company.
In 2021, the Company replaced the 2013 Plan with the 2021 Stock Incentive Plan (the “2021 Plan”), authorizing the granting of equity awards for the issuance of up to 3,000,000 shares of common stock. Upon adoption of the 2021 Plan, no more shares would be issued under the 2013 Plan. Starting on January 1, 2022, the shares authorized under the 2021 Plan shall have an annual increase of the lessor of (a) 3.5% of the aggregate number of shares of common stock outstanding on the final day of the preceding calendar year, or (b) such smaller amount as determined by the Board. On January 1, 2024, an additional 479,828 shares were authorized under the 2021 Plan. As of June 30, 2024, 2,519,149 shares were available for issuance under the 2021 Plan.
The Company recorded total stock-based compensation for its outstanding stock options and warrants in its Statements of Operations as follows (in thousands):
Three Months Ended
June 30,		Six Months Ended June 30,
2024202320242023
Research and development$217 $230 $783 $465 
General and administrative374 82 963 159 
Total stock-based compensation expense$591 $312 $1,746 $624 
Stock options
The following table summarizes the range of assumptions used to estimate the fair value of stock options issued using the Black-Scholes-Merton option pricing model:
Six Months Ended June 30,
20242023
Stock price
$3.76 to $5.19
n/a
Exercise price
$3.76 to $5.19
n/a
Expected volatility
97.06% to 101.55%
n/a
Risk free interest rates
4.12% to 4.46%
n/a
Expected term (years)
5 to 7
n/a
There were no options issued for the six months ended June 30, 2023. For the six months ended June 30, 2024, a dividend yield of 0% was used because the Company has not historically paid and does not intend to pay a dividend on common stock in the foreseeable future. The expected stock price volatility assumption was estimated based on the historical volatilities for industry peers, as the Company had no active market for its stock prior to the IPO and limited history for issuance price of its stock. The risk-free rate assumption is determined using the yield currently available on U.S. Treasury zero coupon issues with a remaining term commensurate with the expected term of the award. The expected term of the option represents the period the options are expected to be outstanding.
The following table summarizes the activity for stock options for the six months ended June 30, 2024:
OptionsWeighted-
Average
Exercise Price		Weighted Average
Remaining
Contractual Term
(in years)		Aggregate
Intrinsic
Value (in
thousands)
Outstanding at December 31, 20231,239,750 $8.00 6.4$1,865 
Issued798,379 $5.06 
Exercised(1,000)$4.00 
Forfeited and cancelled— $— 
Outstanding at June 30, 20242,037,129 $6.85 7.4$538 
Exercisable at June 30, 20241,049,025 $7.58 5.7$302 

All options expire 10 years from date of grant. Options outstanding begin to expire in August 2024. Options that were granted to employees and consultants have vesting periods that vary by award to recipient and range from immediate vesting to a period of up to 4 years.
The weighted average grant date fair value of stock options issued was $4.09 for the three months ended June 30, 2024.
As of June 30, 2024, total unrecognized compensation cost related to options was approximately $3.4 million and is expected to be recognized over the remaining weighted average service period of 2.2 years.
Warrants
The following table summarizes the range of assumptions used to estimate the fair value of warrants issued using the Black-Scholes-Merton option pricing model:
Six Months Ended June 30,
20242023
Stock price
$4.50 to $5.19
$4.50 to $5.00
Exercise price
$4.50 to $5.19
$6.00 to $6.25
Expected volatility
97.06% to 100.64%
101.46% to 103.85%
Risk free interest rates
4.12% to 4.39%
3.59% to 3.97%
Expected term (years)
 5 to 6.25
3 to 5
For the six months ended June 30, 2024 and 2023, a dividend yield of 0% was used because the Company has not historically paid and does not intend to pay a dividend on common stock in the foreseeable future. The expected stock price volatility assumption was estimated based on the historical volatilities for industry peers, as the Company had no active market for its stock prior to the IPO and limited history for issuance price of its stock. The risk-free rate assumption is determined using the yield currently available on U.S. Treasury zero coupon issues with a remaining term commensurate with the expected term of the award. The expected term of the warrant represents the period the warrants are expected to be outstanding.
The following table summarizes the activity for warrants for the six months ended June 30, 2024:
WarrantsWeighted-
Average
Exercise Price		Weighted Average
Remaining Contractual Term
(in years)		Aggregate
Intrinsic
Value (in
thousands)
Outstanding at December 31, 2023801,950 $6.30 3.9$2,096 
Issued50,000 $4.85 
Exercised(2,500)$3.00 
Forfeited and cancelled(20,000)$3.00 
Outstanding at June 30, 2024829,450 $6.31 4.0$186 
Exercisable at June 30, 2024730,700 $6.35 3.6$176 
All warrants outstanding are exercisable for purchase of common stock.
At June 30, 2024, total unrecognized compensation cost related to warrants was approximately $0.3 million and is expected to be recognized over the remaining weighted average service period of 2.4 years.