In September 2018, the Company’s board of directors adopted, and the Company’s stockholders approved, the 2018 Equity Incentive Plan (the “2018 Plan”), which provided for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock units, performance-based stock awards and other forms of equity compensation to the Company’s employees, directors and consultants. In July 2023, the 2018 Plan was replaced by the 2023 Equity Incentive Plan (the "2023 Plan"), as described below. As of July 2023, no additional awards could be made under the 2018 Plan and no shares of common stock were reserved for future issuance. As of December 31, 2024, there are 7 non-statutory stock options outstanding under the 2018 Plan. Three expire in June 2028 and four expire in January 2030.

In September 2018, the Company's board of directors adopted the 2018 Employee Stock Purchase Plan (the “ESPP”), which permitted eligible employees to purchase the Company’s common stock at a discount through payroll deductions during defined offering periods. Eligible employees could elect to withhold up to 15% of their base earnings to purchase shares of the Company’s common stock at a price equal to 85% of the fair market value on the first day of the offering period or the purchase date, whichever was lower. The number of shares of common stock reserved for issuance under the ESPP automatically increased on January 1 of each fiscal year by the lesser of (1) 23 shares, (2) 1.25% of the total number of shares outstanding on December 31 of the preceding fiscal year, or (3) such other amount as the Company’s board of directors may determine.

In April 2024, the Company formally terminated the ESPP. For the years ended December 31, 2024 and December 31, 2023, no cash was received from the exercise of purchase rights under the ESPP in each respective period.

As of December 31, 2024, the Company had issued 95 shares of common stock since inception of the ESPP, and no shares were reserved for future issuance.

As of December 31, 2023, the Company had issued 95 shares of common stock since inception of the ESPP, and 2 shares were reserved for future issuance.

Upon termination of the ESPP in April 2024, the reserved shares were released back to the authorized pool.

In March 2020, the Company adopted the 2020 Inducement Equity Incentive Plan (the “2020 Plan”) for the purpose of attracting, retaining and incentivizing employees in furtherance of the Company’s success. The 2020 Plan was adopted without stockholder approval pursuant to Rule 303A.08 of the New York Stock Exchange. The 2020 Plan is used to offer equity awards as material inducements for new employees to join the Company. Upon adoption of the 2020 Plan, 64 shares of common stock were reserved for the granting of inducement stock options, restricted stock awards, restricted stock units and other forms of equity awards. As of December 31, 2024 and December 31, 2023, 0 and 54 shares of common stock were reserved for future issuance under the 2020 Plan. In April 2024, the Company terminated the 2020 Plan at which time the reserved shares were released back to the authorized pool.

At the closing of the Merger, each outstanding option to purchase Old Catheter common stock that had not previously been exercised prior to the closing of the Merger was assumed and converted into options to purchase 75,367 shares of the Company’s common stock (“Replacement Options”). Additionally, no Old Catheter options were amended in connection with the Merger. All the Replacement Options vested in accordance with the original terms of the grants in place at the time of the Merger. As a result, $3.4 million of the purchase price consideration, which represented the estimated fair value of Old Catheter’s assumed stock options, and $1.1 million of stock-based compensation expense, which represents the excess of the estimated fair value of the Replacement Options over the assumed Old Catheter stock options, were recognized upon the closing of the Merger.

In July 2023, the Company’s stockholders approved the 2023 Plan as defined above, which provided for the grant of incentive stock options, non-statutory stock options, restricted stock awards, restricted stock units, performance-based stock awards and other forms of equity compensation to the Company’s employees, directors and consultants. Stock options granted under the 2023 Plan to employees and consultants generally will vest annually over a five-year period or as determined by the Board’s Compensation Committee, while grants to non-employee directors generally vest quarterly over a three-year period. As of December 31, 2024 and December 31, 2023, 926,882 and 50,186 shares of common stock were reserved for issuance pursuant to future awards under the 2023 Plan. The number of shares available for issuance under the 2023 Plan also includes a quarterly increase commencing on September 1, 2023 by an amount equal to the lesser of (i) 10% of the number equal to the number of shares of common stock outstanding on the applicable adjustment date less the number of shares of common stock outstanding at the beginning of the fiscal quarter immediately preceding the adjustment date, but if such number is a negative number, then the increase will be zero; or (ii) such lesser number of shares as may be determined by the Board.

On January 8, 2024, the Compensation Committee (the "Committee") of the Board approved the issuance of a total of 28,500 non-qualified stock options under the 2023 Plan. During 2024, 7,500 of these non-qualified options were issued to non-employee directors that vest at 8 1/3% per quarter for 3 years with an exercise price of $4.00 and expiration date of January 8, 2034. The remaining 21,000 non-qualified options were issued to employees and consultants and vest at 20% per year for 5 years with an exercise price of $4.00 and expiration date of January 8, 2034.

On February 26, 2024, the Committee approved the issuance of a total of 15,000 incentive stock options under the 2023 Plan. All options were issued to employees and vest at 20% per year for 5 years with an exercise price of $4.20 and expiration date of February 26, 2034.

On April 24, 2024, the Committee approved the issuance of a total of 12,500 incentive stock options under the 2023 Plan. All options were issued to employees and vest at 20% per year for 5 years with an exercise price of $4.60 and expiration date of April 24, 2034.

On July 9, 2024, the Committee approved the issuance of a total of 10,000 incentive stock options under the 2023 Plan. All options were issued to employees and vest at 20% per year for 5 years with an exercise price of $3.50 and expiration date of July 9, 2034.

The options issued for the 2023 Plan for the year ended December 31, 2024 were valued at approximately $262 thousand using the Black-Scholes model based on the following assumptions on the date of issue:

The following is a summary of stock option activity for the options for the year ended December 31, 2024 (in thousands, except for weighted average price and remaining life):

On April 24, 2024, the Board approved the issuance of a total of 25,000 Non-Plan Options as an employment incentive for the position of Chief Commercial Officer. The options were issued on May 1, 2024, the first day of employment and vest at 20% per year for 5 years with an exercise price of $5.321 and an expiration date of May 1, 2034.

The Non-Plan Options issued were valued at approximately $131 thousand using the Black-Scholes model based on the following assumptions on the date of issue:

The following is a summary of stock option activity for the Non-Plan options for the year ended December 31, 2024 (in thousands, except for weighted average price and remaining life):

All restricted stock units have been forfeited or vested as of December 31, 2023.

All restricted stock awards have been forfeited or vested as of December 31, 2023.

Stock-based compensation expense for the years ended December 31, 2024 and 2023 was $54 thousand and $1.2 million, respectively, in selling, general and administrative expenses in the consolidated statements of operations.

Total unrecognized estimated stock-based compensation expense by award type and the remaining weighted average recognition period over which such expense is expected to be recognized at December 31, 2024 was as follows: