AIM Vaccine Co., Ltd. — Proxy Solicitation & Information Statement 2026

May 21, 2026

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this notice, make no representation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this notice.

文美疫苗
全产业链疫苗集团

AIM Vaccine Co., Ltd.

艾美疫苗股份有限公司

(a joint stock company incorporated in the People's Republic of China with limited liability)

(Stock Code: 6660)

NOTICE OF THE 2026 FIRST EXTRAORDINARY GENERAL MEETING

NOTICE IS HEREBY GIVEN THAT the 2026 first extraordinary general meeting (the "EGM") of AIM Vaccine Co., Ltd. (the "Company") will be held at meeting room, 10/F, Gangwu Building, No. 1 Fenghe Road, Lujiazui Street, Pudong New District, Shanghai, the PRC at 10:30 a.m. (or immediately after the conclusion of the 2025 Annual General Meeting) on Wednesday, June 10, 2026 for the purpose of considering and, if thought fit, passing, with or without amendments, the following resolutions.

SPECIAL RESOLUTIONS

1. To consider and approve the private issuance of RMB Ordinary Shares, the application for the listing and public transfer of RMB Ordinary Shares on the National Equities Exchange and Quotations by the Company, as well as the subsequent plan to apply for the listing of A Shares on the Beijing Stock Exchange.

2. To consider and approve the Company's application to adopt the call auction trading method for the listing of RMB Ordinary Shares on the National Equities Exchange and Quotations.

3. To consider and approve the Company's plan for the private issuance of RMB Ordinary Shares (each and every item as a separate resolution):

i. Class and nominal value of the Shares to be issued: unlisted RMB Ordinary Shares, with a nominal value of RMB1.00 per Share.

ii. Number of the Shares to be issued: not more than 40,000,000 Shares.

iii. Target subscribers: not more than 35, the scope of which includes the registered Shareholders of the Company and other eligible investors who comply with the regulations on investor suitability management.

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iv. Issue price: RMB3.0 to RMB8.0 per Share, which will be determined by the Board and its authorized persons at the time of the final issuance based on market practices and regulatory requirements, taking into full consideration the interests of Shareholders, investor acceptance and issue risks, as well as the market conditions at that time, the net asset value per Share, and the Company’s secondary market share price.

v. Method of issuance: by way of a non-public issuance of RMB Ordinary Shares to selected target subscribers, and methods such as public roadshows or book building will not be adopted.

vi. Lock-up arrangements: save for the lock-up circumstances stipulated by laws and the Articles of Association, there are no other lock-up arrangements for the Issuance; after the target subscribers are confirmed, all target subscribers shall sign relevant agreements. If there are lock-up arrangements or voluntary lock-up commitments for the new Shares, the specific arrangements shall be subject to the subscription agreements, voluntary lock-up commitments and other documents.

vii. Disposal of accumulated undistributed profits: the accumulated undistributed profits prior to the completion of the Issuance shall be shared by all Shareholders of the Company upon the completion of the Issuance in proportion to their respective shareholdings at the relevant time.

viii. Use of proceeds: the proceeds from the Issuance will be used to supplement working capital, to optimize the capital structure of the Company, enhance its capital scale, further strengthen its financial strength, improve its profitability and risk resistance, facilitate the Company to better achieve scale expansion and business development, and enhance its overall competitiveness.

ix. Place of listing: the RMB Ordinary Shares in issue and the RMB Ordinary Shares under the Issuance will be listed on the National Equities Exchange and Quotations, which are also planned to apply for listing on the Beijing Stock Exchange.

x. Validity period of the resolution in relation to the Issuance: the resolution in relation to the Issuance shall be valid for 12 months from the date on which the issuance plan of the Issuance is considered and approved at the EGM. If, within the validity period, the Company obtains the consent letter from National Equities Exchange and Quotations Co., Ltd. or the registration approval from the China Securities Regulatory Commission for the Issuance, the validity period shall be automatically extended until the date of completion of the matters relating to the Issuance.

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1. To consider and approve the authorization by the general meeting to the Board to handle, at its full discretion, matters relating to the Company’s application for the listing and public transfer of RMB Ordinary Shares on the National Equities Exchange and Quotations and the simultaneous private issuance of RMB Ordinary Shares.

i. formulating and implementing the specific plan for the Listing and the Issuance in accordance with laws, regulations and relevant requirements of the regulatory authorities and the National Equities Exchange and Quotations, including but not limited to determining the number of Shares to be issued, target subscribers, final price, timing and method of the Issuance, lock-up period, specific investment amount for the use of the proceeds from the Issuance and other relevant matters; and making appropriate amendments to the contents related to the plan for the Listing and the Issuance based on the actual circumstances of the Issuance and the approval documents or requirements of relevant regulatory authorities.

ii. engaging intermediaries to handle matters relating to the filing, auditing, capital verification, and valuation of the Listing and the Issuance, and determining their professional service fees.

iii. drafting, signing, modifying and executing relevant contracts (including but not limited to stock subscription agreements) and important documents (including but not limited to the public transfer prospectus, private issuance prospectus and other documents) relating to the Listing and the Issuance, and submitting and filing various applications and making various replies.

iv. determining the specific arrangement for the use of proceeds from the Listing and the Issuance in the proposed investment projects based on actual circumstances, and adjusting the specific arrangement of the amount of proceeds in accordance with legal requirements, requirements of regulatory authorities and market conditions.

v. handling all matters relating to the filing, review, registration and issuance of the Listing and the Issuance, including but not limited to: handling approval, registration, filing, verification and consent procedures in respect of the Listing and the Issuance with relevant government agencies, regulatory authorities, stock exchanges and securities registration and clearing institutions; approving, preparing, signing, executing, modifying and completing various documents relating to the Listing and the Issuance.

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vi. making corresponding amendments to the relevant articles in the Articles of Association concerning the registered capital and share capital structure of the Company upon completion of the Issuance based on the results of the Listing and the Issuance, and handling the change of registration/filing with industrial and commercial departments and securities registration and clearing institutions; and amending relevant articles in the Articles of Association and other governance systems based on the actual situation of the Company.

vii. fulfilling information disclosure obligations relating to the Listing and the Issuance in accordance with laws, regulations, normative documents of the CSRC, rules for the issuance of shares on the National Equities Exchange and Quotations and the Articles of Association; approving the publication of announcements, circulars and notices relating to the Listing and the Issuance on the National Equities Exchange and Quotations, the Stock Exchange and the Company’s websites, and submitting relevant forms, documents or other information to the Stock Exchange.

viii. adjusting, suspending or terminating the specific plan for the Listing and the Issuance within the scope permitted by laws, regulations, normative documents, the Articles of Association and resolutions of the general meeting, based on the implementation of the plan for the Listing and the Issuance, market conditions, policy adjustments, ex-rights and ex-dividend matters and opinions of regulatory authorities.

ix. handling all other matters required for the Listing and the Issuance, and taking all actions and matters deemed desirable or appropriate in connection with the Listing and the Issuance, to the extent permitted by relevant laws and regulations.

The above authorization, if approved, shall be valid for 12 months from the date of approval at the EGM. If, within the validity period of the authorization, the Company obtains the consent letter from National Equities Exchange and Quotations Co., Ltd. or the registration approval from the China Securities Regulatory Commission for the Listing and the Issuance, the term of the relevant authorization shall be automatically extended until the date of completion of the matters relating to the Listing and the Issuance.

1. To consider and approve the Private Issuance Prospectus of AIM Vaccine Co., Ltd.

2. To consider and approve the amendments to the Articles of Association, the Rules of Procedure of the General Meeting and the Rules of Procedure of the Board of Directors of the Company as set out in Appendices I, II and III to the circular, respectively. Such amendments shall become effective upon the date of the Company’s official listing on the National Equities Exchange and Quotations.

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ORDINARY RESOLUTIONS

1. To consider and approve the engagement of relevant intermediaries in respect of the Company’s application for the listing and public transfer of RMB Ordinary Shares on the National Equities Exchange and Quotations and the simultaneous private issuance of RMB Ordinary Shares.

2. To consider and approve that the existing Shareholders of the Company shall not be entitled to pre-emptive rights for the Shares under the Issuance.

3. To consider and approve the opening of an account designated for the proceeds and the signing of a tripartite supervision agreement.

4. To consider and approve the assessment of the implementation of the Company’s governance mechanisms.

5. To consider and approve the formulation and amendment of the Company’s relevant governance systems.

Details of the above resolutions are set out in the circular. Unless otherwise indicated, capitalized terms used in this notice shall have the same meanings as those defined in the circular.

By order of the Board
AIM Vaccine Co., Ltd.
Chairman of the Board and CEO
Mr. Yan ZHOU

Beijing, the PRC, May 21, 2026

Notes:

1. All resolutions at the EGM will be taken by poll (except where the chairman decides to allow a resolution relating to a procedural or administrative matter to be voted on by a show of hands) pursuant to the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited. The results of the poll will be published on the website of Hong Kong Exchanges and Clearing Limited (www.hkexnews.hk) and the Company’s website (www.aimbio.com) after the EGM.

2. Any Shareholder entitled to attend and vote at the EGM convened by the above notice may appoint one or more proxies to attend the meeting and vote instead of him/her while voting by poll. A proxy needs not be a Shareholder of the Company.

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1. To be valid, the proxy form together with the power of attorney or other authority, if any, under which it is signed, or a certified copy of such power of attorney or authority, must be completed and returned to the Company's H Share registrar, Tricor Investor Services Limited at 17/F, Far East Finance Centre, 16 Harcourt Road, Hong Kong, at least 24 hours before the time scheduled for holding the meeting (i.e. before 10:30 a.m. on Tuesday, June 9, 2026) or any adjourned meeting thereof (as the case may be). Completion and return of the form of proxy will not preclude the Shareholders of the Company from attending and voting in person at the meeting, and in such event, the instrument appointing a proxy shall be deemed to be revoked.

2. For the purpose of determining the list of H Shareholders who are entitled to attend and vote at the EGM, the register of members of the Company will be closed from Friday, June 5, 2026 to Wednesday, June 10, 2026, both days inclusive, during which period no transfer of Shares will be registered. The record date for determining the identity of the Shareholders who are entitled to attend and vote at the EGM will be Wednesday, June 10, 2026. In order to be eligible to attend and vote at the EGM, unregistered H Shareholders shall ensure that all transfer documents accompanied by the relevant share certificates must be lodged with the Company's H Share registrar, Tricor Investor Services Limited at 17/F, Far East Finance Centre, 16 Harcourt Road, Hong Kong, before 4:30 p.m. on Thursday, June 4, 2026 for transfer registration.

3. In case of joint Shareholders, the vote of the senior joint Shareholder who tenders a vote, whether in person or by proxy, will be accepted to the exclusion of the votes of the other joint Shareholder(s). For this purpose, seniority will be determined by the order in which the names stand in the H Share register of members of the Company in respect of the joint shareholding.

4. Shareholders who attend the meeting in person or by proxy shall bear their own travelling and accommodation expenses.

5. A Shareholder or his/her proxy should produce proof of identity when attending the EGM.

6. The contact details of the above meeting are:

The Office of the Board of AIM Vaccine Co., Ltd.
Address: Room 412, 4/F, Building 6, No. 105 Jinghai 3rd Road, Beijing Economic-Technological Development Area, Beijing, the PRC
Postal code: 100000
Phone: +86 10-8595 0689
Email: aim.securities@aimbio.com

1. Further details of the resolutions are set out in the circular of the Company dated May 21, 2026 (the "Circular"). Unless otherwise indicated, capitalized terms used in this notice shall have the same meanings as those defined in the Circular.

2. All dates and time in this notice refer to Hong Kong dates and time.

As at the date of this notice, the Board comprises Mr. Yan ZHOU, Mr. Xin ZHOU, Mr. Shaojun JIA, Mr. Wen GUAN and Mr. Jie ZHOU as executive directors; Mr. Jichen ZHAO as a non-executive director; and Professor Ker Wei PEI, Ms. Jie WEN and Mr. Xiaoguang GUO as independent non-executive directors.

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