8.    Stockholders’ Equity

The Company is authorized to issue an aggregate of 21,666,666 shares of capital stock, par value $0.001 per share, consisting of 1,666,666 shares of common stock and 20,000,000 shares of preferred stock.

Unless otherwise noted, all share and per share amounts have been adjusted retrospectively, to reflect the Reverse Stock Split. See “Note 2, Summary of Significant Accounting Policies—Basis of Presentation” and “Note 11, Subsequent Events” in this Quarterly Report for additional information.

As of June 30, 2026 and December 31, 2025, 953,192 and 815,145 shares, respectively, of common stock were issued and outstanding. No shares of preferred stock have been issued.

During the six months ended June 30, 2026, the Company issued an aggregate of 138,047 shares (post-Reverse Stock Split) of common stock under the Sales Agreement resulting in net proceeds of approximately $1.2 million.

Warrants

In the January 2025 Public Offering, the Company issued pre-funded warrants, which were immediately exercised for 47,849 shares of common stock at $29.76 per share (post-Reverse Stock Split), and 87,366 January 2025 Warrants at an exercise price of $28.32 per share (post-Reverse Stock Split). In August 2025, as part of the Warrant Inducement, the Company issued 49,933 shares of common stock upon exercise of the January 2025 Warrants for a price of $15.72 (post-Reverse Stock Split) per share. As of June 30, 2026, 37,433 of the January 2025 Warrants remain outstanding.

In 2024, 8,125,000 Series B Warrants exercisable for 41,353 shares at $1.20 per share (post-Reverse Stock Split) were exercised using the cashless conversion option which resulted in the issuance of 17,973 shares of common stock (based on a $62.472 reset price, both post-Reverse Stock Split). Another 46,300,000 Series B Warrants were exercised on a cash basis which resulted in the issuance of 89,891 shares of common stock (based on a $62.472 reset price, both post-Reverse Stock Split). In July 2025, 3,000,000 warrants were exercised on a cash basis, which resulted in the issuance of 7,104 shares $62.472 reset price, both post-Reverse Stock Split. In 2024, 323,203 Series A Warrants were exercised on a cash basis which resulted in the issuance of 1,242 of common stock $62.472 reset price, both post-Reverse Stock Split. In August 2025, as part of the Warrant Inducement, the exercise price of the Series A Warrants was reduced to $15.72 per share, and 365,396 shares (post-Reverse Stock Split) were issued upon exercise of 95,112,212 warrants. As of June 30, 2026, there were 19,564,585 Series A Warrants exercisable for 75,172 shares and 75,000 Series B Warrants exercisable for 178 shares outstanding.

Below is a summary of warrants issued and outstanding as of June 30, 2026:

Warrant Inducement and Repricing

On August 14, 2025, the Company entered into an inducement offer letter agreements with certain holders of the Series A Warrants and the January 2025 Warrants, which reduced the exercise price of the Series A Warrants from $62.472 to $15.72 per share (post-Reverse Stock Split), and the January 2025 Warrants from $28.32 to $15.72 per share (post-Reverse Stock Split). The difference between the fair value of the warrants immediately prior to and following modification was treated as a transaction cost, which was netted against proceeds received. The difference in fair value for the Series A Warrants was $1,423,166, and the difference in fair value for the January 2025 Warrants was $97,746. Both were calculated using the Black-Scholes option-pricing model and were based on the following assumptions:

Equity Plans

As of December 31, 2024, the Company adopted two stock-based compensation plans, the 2021 Incentive Award Plan (the “2021 Plan”) and the 2021 Employee Stock Purchase Plan (the “2021 ESPP”).

2021 Incentive Award Plan

The purpose of the 2021 Plan is to enhance the Company’s ability to attract, retain and motivate persons who make (or are expected to make) important contributions to the Company by providing these individuals with equity ownership opportunities. Various stock-based awards may be granted under the 2021 Plan to eligible employees, consultants, and non-employee directors, including options and RSUs.

The number of shares issued under the 2021 Plan is subject to an initial limit and is adjusted annually pursuant to an evergreen provision. The aggregate share limit will be subject to an annual increase on the first day of each calendar year ending on and including January 1, 2031, by a number of shares equal to the lesser of (i) a number equal to 5% of the aggregate number of shares of the Company's common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as is determined by the Company's board or committee. On January 1, 2026, an aggregate of 40,757 (post-Reverse Stock Split) shares were added to the plan reserve pursuant to the evergreen provision based on the number of shares outstanding as of December 31, 2025.

The type of award, number of shares subject to the award, exercise price (if any), vesting provisions (if any), and other terms of the awards will be determined at date of grant; however, the exercise price of options shall not be less than 100% of the fair value on the grant date and the term of options shall not exceed ten years.

As of June 30, 2026, an aggregate of 113,485 shares were eligible to be issued under the 2021 Plan, of which 17,896 shares underlying options and 46,713 shares underlying RSUs had been granted (all post-Reverse Stock Split). Regardless of the number of shares authorized for issuance under the 2021 Plan, no more than 833 shares may be issued pursuant to the exercise of incentive stock options granted under the plan, which reflects an adjustment under the 2021 Plan following the Reverse Stock Split and the Company’s reverse stock split effected in 2024. The majority of stock options that have been issued by the Company are non-qualified stock options.

During the three and six months ended June 30, 2026, the Company did not grant any options or RSUs, and no options or RSUs were forfeited or canceled.

The stock-based compensation expenses incurred during the three months ended June 30, 2026 and 2025 were $51,839 and $133,229, respectively and during the six months ended June 30, 2026 and 2025 were $105,029 and $183,951, respectively.

2021 Employee Stock Purchase Plan

The purpose of the 2021 ESPP is to assist eligible employees of the Company in acquiring stock ownership in the Company, help them provide for their future security, and encourage them to remain in the employment of the Company.

The number of shares issued under the 2021 ESPP is subject to an initial limit and is adjusted annually pursuant to an evergreen provision. The aggregate share limit will be subject to an annual increase on the first day of each calendar year ending on and including January 1, 2031, by a number of shares equal to the lesser of (i) a number equal to 1% of the aggregate number of shares of the Company's common stock outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as is determined by the Company's board or committee. On January 1, 2026, an aggregate of 8,151 shares (post-Reverse Stock Split) were added to the plan reserve pursuant to the evergreen provision based on the number of shares outstanding as of December 31, 2025.

The 2021 ESPP consists of a Section 423 Component and Non-Section 423 Component. The Section 423 Component is intended to qualify as an employee stock purchase plan and also authorizes the grant of options. Options granted under the Non-Section 423 Component shall be granted pursuant to separate offerings. The Company may make one or more offerings under the 2021 ESPP. The duration and timing of each offering period may be established or changed by the board, but in no event may an offering period exceed 27 months and in no event may the purchase period for the option exceed the duration of the offering period under which it is established. On each exercise date for an offering period, each participant shall automatically be deemed to have exercised the option to purchase the largest number of whole shares which can be purchased under the offering. Option awards are generally granted with an exercise price equal to 85% of the lesser of the fair market value of a share on (a) the applicable grant date and (b) the applicable exercise date, or such other price as designated by the administrator.  

As of June 30, 2026, an aggregate of 51,818 shares were eligible to be issued under the 2021 ESPP. No shares have been issued under the 2021 ESPP. 

The Company uses the “simplified method” to estimate expected term. Under the simplified method, an option’s expected term is calculated as the time until expiration.

No options were granted, forfeited, or canceled during the three months ended June 30, 2026, and no RSUs were granted, forfeited, or vested during the same period. As of June 30, 2026, there were 17,858 options outstanding with a weighted average exercise price of $241.41 each, with 17,844 options exercisable at the same date, with a weighted average exercise price of $238.35 each. As of June 30, 2026, there were 3,333 RSUs granted but unvested, with a weighted average grant-date fair value of $18.00 each (post-Reverse Stock Split).

Common Stock Reserved for Future Issuance

The following is a summary of shares of common stock reserved for future issuance as of June 30, 2026: