HCW Biologics Inc.

Insider Adoption or Termination of Trading Arrangements

During the fiscal quarter ended March 31, 2026, none of our directors or officers informed us of theadoption, modification ortermination of a “Rule 10b5-1 trading arrangement” or “non-Rule 10b5-1 trading arrangement,” as those terms are defined in Regulation S-K, Item 408.

Secured Note Financing

On March 28, 2024, the Company entered into a senior secured note purchase agreement (the “Note Purchase Agreement”) with the Purchasers (as defined in the Note Purchase Agreement), pursuant to which we agreed to issue senior secured notes in an aggregate principal amount of up to $10.0 million (“Secured Notes”) to certain accredited investors, including unrelated parties as well as officers and directors of the Company. As of March 31, 2024, the Company had an initial closing and issued $2.0 million in Initial Secured Notes. As of June 30, 2024, all existing investors approved an Amended and Restated Note Purchase Agreement (“Amended and Restated Note Purchase Agreement”), with terms described below. As of September 30, 2024, the Amended and Restated Note Purchase Agreement was amended to extend the last closing date to issue Additional Secured Notes to October 31, 2024. The material terms of the Additional Secured Notes are identical to the terms of the Initial Secured Notes.

As of October 31, 2024, the Company issued an aggregate of $6.9 million of Secured Notes, with $2.9 million from the Company’s officers and members of the board of directors, including $2.4 million purchased by Dr. Hing C. Wong, Founder and CEO, $220,000 purchased by Rebecca Byam, Chief Financial Officer, $140,000 purchased by Scott T. Garrett, Chairman of the board of directors, $60,000 purchased by Gary M. Winer, who was serving as a member of the board of directors at the time of his investment, $25,000 purchased by Lee Flowers, Senior Vice President for Business Development, and $25,000 purchased by Rick S. Greene, member of the board of directors.

The Senior Notes bear interest at a rate of 9% per annum, payable quarterly in arrears, and mature on August 30, 2026 (the “Maturity Date”), on which date the principal balance, accrued but unpaid interest, and other amounts that may be due under the terms of the Amended and Restated Note Purchase Agreement shall be due and payable. The Secured Notes may be prepaid on or prior to December 31, 2024, but will be subject to a 5% prepayment penalty (“Premium Amount”). Thereafter, the Senior Notes may be repaid upon a Mandatory Redemption event or at the end of the term.

As a condition to entering into the Amended and Restated Note Purchase Agreement, the Company, Mercedes M. Sellek, P.A. (“Escrow Agent”), and the Purchasers entered into that certain Escrow Agreement and Amended and Restated Pledge Agreement, dated July 2, 2024, pursuant to which the Company agreed to pledge our equity ownership interest in Wugen (the “Pledged Collateral”), to be held and released by Escrow Agent according to the terms of the Escrow Agreement, as security for the Secured Notes.

Upon a qualifying event involving a transaction such as an acquisition, merger or initial public offering in which the Pledged Collateral can be sold or liquidated prior to the Maturity Date, subject to certain limitations (such as a threshold price per share in the case of an initial public offering), the Company agreed to repay all indebtedness (including accrued interest) related to the Secured Notes plus a Bonus Payment (as defined in the Amended and Restated Note Purchase Agreement). If there is no such mandatory redemption prior to the Maturity Date, the Company agreed to pay the holders of Secured Notes a Bonus Payment under certain circumstances.

Upon an Event of Default (as defined in the Amended and Restated Note Purchase Agreement), the Company will have a thirty (30) day cure period (the “Cure Period”), and if the Event of Default is not so cured at the end of the Cure Period, the Company is required to distribute the Pledged Collateral to the Purchasers on apro rata basis, determined based on the issuance of $10.0 million in Secured Notes, in full satisfaction of the indebtedness evidenced by the Secured Notes.

The issuance of the Additional Secured Notes was exempt from the registration requirements of the Securities Act of 1933, as amended, in accordance with Section 4(a)(2), as a transaction by an issuer not involving a public offering. In addition, our Board of Directors and the Audit Committee of our Board of Directors reviewed the transaction under our policy for Related Party Transactions (the “Policy”) and determined that the issuance of the Additional Secured Notes was in compliance with the Policy.

On February 20, 2025, the Company and certain Noteholders agreed to Principal Terms for Conversion of their Secured Notes. Noteholders and the Company agreed that, subject to stockholder approval, at least $6.6 million in principal amount of the Secured Notes will be converted into shares of our Common Stock at a conversion price of $26.00 per share. As part of the conversion, the Company will issue warrants to purchase shares of our Common Stock to the converting Noteholders for up to an additional $3.3 million of shares of our Common Stock, at an exercise price of $26.00 per share. Upon conversion, converting Noteholders would be subject to a lock-up period of 180 days from the date of conversion. Further, the Escrow Agreement will be amended such that the proceeds from the Pledged Collateral will be allocated among the Company and the converting Noteholders, as provided for in the Principal Terms. The conversion of principal amount of the Secured Notes will result in a dollar-for-dollar increase in stockholders’ equity (partially offset by the carrying value of the portion of the Company’s investment in the Pledged Collateral the proceeds of which will be paid to converting Noteholders), contributing to the Company’s plan to gain compliance with the Nasdaq Minimum Shareholder Equity Rule and to maintaining listing of the our Common Stock on Nasdaq.

The Principal Terms of Conversion were approved at a Special Meeting of Stockholders held on March 31, 2025 and were effected pursuant to the terms of that certain Second Amendment to Amended and Restated Senior Secured Note Purchase Agreement and Related Agreements dated as of May 1, 2025 (the “Conversion Amendment”). On May 7, 2025, pursuant to the Conversion Amendment, the Secured Notes held by the participating noteholders were cancelled, and the Company issued a total of 253,083 unregistered shares of Common Stock (which are subject to a 180-day lock-up) and warrants to purchase an additional 126,540 shares of Common Stock at an exercise price of $26.00 per share. On January 29, 2026, the SEC declared effective a resale registration statement on Form S-1 (File Number 333-292652) covering the resale of shares of Common Stock and warrants issued to such note holders.

Unsecured Promissory Notes

As of May 5, 2025, the Company issued a total of $270,000 principal amount of unsecured convertible promissory notes that mature on May 5, 2026 with paid in kind interest accruing thereon, payable quarterly in arrears at 10% per annum (the “Convertible Bridge Notes”). In accordance with their terms, following the completion of a qualified offering, the Convertible Bridge Notes were converted into shares of our Common Stock at the final offering price in an offering that closed on May 15, 2025. In addition, holders of the Convertible Bridge Notes have the right to receive a portion of the proceeds of the Company’s shares of Wugen common stock, if and when such shares are ever sold, determined by the number of the Wugen shares equal to 0.25 multiplied by the original principal amount, in dollars, of the Convertible Bridge Notes. Investors included: $60,000 invested by Hing C. Wong, the Company’s Founder and CEO; $100,000 invested by Scott T. Garrett, the Chairman of the Company’s Board of Directors; and $10,000 invested by Gary M. Winer, who was serving as a member of the Company’s Board of Directors at the time of his investment. As of May 15, 2025, the outstanding principal of Convertible Bridge Notes were converted upon completion of a $5.0 million equity financing.

Special Meeting of Stockholders

As required in the $1.5 million equity offering and repricing of existing warrants that closed on February 19, 2026, the Company held a Special Meeting of Stockholders on April 27, 2026 at 10:00 a.m. Eastern Time. At the Special Meeting the Company submitted the following two proposals to its stockholders for approval:

Proposal 1: To approve, for purposes of complying with Nasdaq Listing Rule 5635(d), the issuance of shares of our Common Stock upon exercise of up to 2,477,292 Common Stock Purchase Warrants (the “Common Warrants”) issued pursuant to that certain Securities Purchase Agreement, dated February 17, 2026 (the “SPA”), entered into in connection with the Company’s follow-on public offering of Units (the “Offering”), which Offering was conducted pursuant to a registration statement (the “Registration Statement”) declared effective by the SEC on February 17, 2026 and closed on February 19, 2026, as previously disclosed in the Company’s Current Report on Form 8-K filed on February 19, 2026, each Unit consisting of (i) one share of Common Stock or one Pre-Funded Warrant to purchase one share of Common Stock and (ii) one Common Warrant, with such Common Warrants exercisable only upon receipt of stockholder approval and having an exercise price equal to 100% of the public offering price per Unit, and such additional terms and conditions of the Common Warrants not materially inconsistent with the foregoing as our Board may hereafter approve; and

Proposal 2: To approve, for purposes of complying with Nasdaq Listing Rule 5635(d), the repricing of certain warrants issued on November 20, 2025 to purchase up to 3,020,410 shares of our Common Stock (the “Existing Warrants”) pursuant to that certain Existing Warrants Amendment Agreement, dated February 17, 2026, entered into in connection with the Offering conducted pursuant to the Registration Statement (as disclosed in the Company’s Current Report on Form 8-K filed on February 19, 2026), to reduce the exercise price of the Existing Warrants from $2.41 per share to $0.6055 per share, and to approve the issuance of shares of our Common Stock upon exercise of the Existing Warrants as so amended, and such additional terms and conditions of such amendment not materially inconsistent with the foregoing as our Board may hereafter approve.

The Special Meeting was adjourned due to lack of quorum. These two proposals were added to the proposals presented to stockholders for their consideration in a definitive proxy filed for the Annual Meeting on April 28, 2026.

Change in Quorum Approved Unanimously by Board of Directors

On April 15, 2026, our Board of Directors unanimously approved and adopted an amendment to the Company’s Bylaws (as amended and restated to date, the “Bylaws”). The amendment, which is effective from and after April 28, 2026, lowers the quorum requirement contained in Section 1.5 of the Bylaws to provide that holders of thirty-three and one-third percent (33 1/3%) of the voting power, which includes the voting power that is present in person or by proxy, regardless of whether the proxy has authority to vote on any matter, constitutes a quorum for the transaction of business.

Annual Meeting of Stockholders

On April 28, 2026, the Company filed a definitive proxy for our Annual Meeting to be held on June 15, 2026, at which the Company will submit the following five proposals to its stockholders for approval:

1. Election of Directors. To elect the Class II directors listed in the accompanying proxy statement to serve a three-year term expiring at the 2029 annual meeting of stockholders and until such director’s successor is duly elected and qualified or until such director’s earlier death, resignation, disqualification or removal (“Proposal One”).

2. Appointment of Company’s Auditors. To ratify the appointment of Crowe LLP as the independent registered public accounting firm of HCW Biologics Inc. for the fiscal year ending December 31, 2026 (“Proposal Two”).

3. Reverse Stock Split to Maintain Nasdaq Listing. To approve an amendment to the Company’s certificate of incorporation on or before the one (1) year anniversary of the Annual Meeting, to implement one or more reverse stock splits of the outstanding shares of the Company’s common stock, par value $0.0001 per share (our “Common Stock”) (as necessary to maintain a listing of our Common Stock on The Nasdaq Stock Market LLC (“Nasdaq”)) in an aggregate range from one-for-five (1::5) up to one-for-twenty (1::20). (“Proposal Three”).

4. Issuance of Shares Upon Exercise of Common Warrants. To approve, for purposes of complying with Nasdaq Listing Rule 5635(d), the issuance of shares of our Common Stock upon exercise of up to 2,477,292 Common Stock Purchase Warrants (the “Common Warrants”) issued pursuant to that certain Securities Purchase Agreement, dated February 17, 2026, entered into in connection with the Company’s follow-on public offering of Units, consisting of one share of Common Stock purchased for $0.6055 and one Common Warrant which may be exercised to purchase one share of Common Stock for $0.6055 per share. The Company is obliged to submit this proposal for a stockholders’ vote every 60 days, until passed. (“Proposal Four”); and

5. Warrants Repricing Proposal. To approve, for purposes of complying with Nasdaq Listing Rule 5635(d), the repricing of certain warrants issued on November 20, 2025 to purchase up to 3,020,410 shares of our Common Stock pursuant to that certain Existing Warrants Amendment Agreement, dated February 17, 2026, to reduce the exercise price of the Existing Warrants to $0.6055 per share, and to approve the issuance of shares of our Common Stock upon exercise of the Existing Warrants as so amended. The Company is obliged to submit this proposal for a stockholders’ vote every 60 days, until passed or until such warrants are no longer outstanding**.** (“Proposal Five”).

The complete definitive proxy statement is included in Exhibit 10.40 to this Quarterly Report.