SinoMab BioScience Limited — Regulatory Filings 2025

Aug 12, 2025

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SINOMAB

SinoMab BioScience Limited

中國抗體製藥有限公司

(Incorporated in Hong Kong with limited liability)

(Stock code: 3681)

VOLUNTARY ANNOUNCEMENT COMPREHENSIVE STRATEGIC COOPERATION AGREEMENT

This announcement is made by the board (the "Board") of directors (the "Directors") of SinoMab BioScience Limited (the "Company", together with its subsidiaries, the "Group") on a voluntary basis to keep the shareholders (the "Shareholders") of the Company and potential investors informed of the latest business development of the Group.

COMPREHENSIVE STRATEGIC COOPERATION AGREEMENT

The Board is pleased to announce that on 12 August 2025, the Company has entered into a comprehensive strategic cooperation agreement (the "Cooperation Agreement") with Sun Yat-sen University Institute of Advanced Studies Hong Kong Limited ("Sun Yat-sen University Institute of Advanced Studies Hong Kong" or "SYSU-IAS") (together with the Company, referred to as the "Parties"), pursuant to which the Parties agreed to a three-year cooperation to jointly conduct research and development in the field of biomedicine. A summary of principal terms of the Cooperation Agreement is set out below:

Date

12 August 2025

Parties

(i) The Company
(ii) Sun Yat-sen University Institute of Advanced Studies Hong Kong

Duration

The term of the Cooperation Agreement shall be three (3) years from the commencement date (i.e. from 12 August 2025 to 11 August 2028).

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Scope of Cooperation

The Parties shall cooperate in the following areas:

Joint Research Efforts: The Parties will leverage mutual expertise to jointly conduct scientific research, including discovery research, target elucidation, and animal model development for debilitating diseases; SYSU-IAS shall be responsible for the provision of experimental site and the supply of animals for such joint research studies.

Joint Usage of Facilities: SYSU-IAS shall grant the Company access to its laboratories located at Shenzhen Futian International Biomedical Industry Park, Shenzhen, Mainland China for the purpose of conducting joint scientific research. The laboratories shall be formally designated as the “Sun Yat-sen University Institute of Advanced Studies Hong Kong — SinoMab BioScience Limited Joint Laboratory”.

Technical Support: SYSU-IAS shall provide technical support to the Company in key areas, including regulatory consultation with relevant health authorities such as Hong Kong’s Department of Health, United States (“U.S.”) Food and Drug Administration, and China’s National Medical Products Administration, identification of suitable clinical sites, and the conduct of animal studies.

Drug Development: The Company will select and provide at least one drug candidate for IND filing and clinical development in the U.S. and China, and will also be responsible for all aspects of this clinical development, including the design, execution, and funding of the trials. Prior to any drug candidate selected by the Company is provided to SYSU-IAS for the joint research, the Parties shall execute a Material Transfer Agreement (MTA), which will be prepared by the Company.

Training and Knowledge Exchange: The Parties shall facilitate training programs and personnel exchange to enhance expertise in research and development of therapeutics for debilitating diseases, including fostering collaboration and establishing connections among the Company, SYSU-IAS and the University of Oxford in biomedical research innovation and transformation of innovative achievements.

Project Funding

Pursuant to the Cooperation Agreement, the Company shall provide SYSU-IAS with funding of HKD1,000,000 per calendar quarter to support the projects and work under the cooperation detailed above. These funds are earmarked to cover all necessary project-related expenditures under the Cooperation Agreement, including personnel costs, direct research expenses, and supporting administrative overhead. The actual expenditure will be determined by the project’s operational requirements. Of the funds provided, an annual amount of HKD1,000,000 shall be paid first by SYSU-IAS to the University of Oxford to advance the Parties’ joint efforts with the University of Oxford on research innovation and its clinical translation.

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Intellectual Property Rights

The Cooperation Agreement shall not alter the intellectual property rights owned by either Party prior to its commencement. All intellectual property rights generated hereunder shall be owned by the Parties in accordance with their respective contributions; contributions shall be determined to be equal if cannot be otherwise agreed upon.

INFORMATION OF THE COMPANY AND THE GROUP

The Company is a limited liability company incorporated under the laws of Hong Kong. The Shares have been listed on the Main Board of the Stock Exchange since 12 November 2019. The Group is principally engaged in the research, development, manufacturing and commercialization of therapeutics for the treatment of immunological diseases, primarily monoclonal antibody-based biologics.

INFORMATION OF SUN YAT-SEN UNIVERSITY INSTITUTE OF ADVANCED STUDIES HONG KONG

Sun Yat-sen University Institute of Advanced Studies Hong Kong is a research institution established by the Sun Yat-sen University. It was established in Hong Kong on 8 February 2024. The institute is dedicated to high-level academic research, interdisciplinary collaboration, and fostering exchanges and cooperation between mainland China and Hong Kong in fields such as science, technology, and humanities.

To the Directors' knowledge, information and belief, and having made all reasonable enquiries, SYSU-IAS and its ultimate beneficial owners are third parties independent of the Company or any of its connected persons (as defined in the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited (the "Listing Rules")).

REASONS AND BENEFITS FOR THE COOPERATION

This Cooperation Agreement aims to leverage the combined strengths of the Company and SYSU-IAS to accelerate the development of innovative drugs and promote the translation of scientific research into clinical applications worldwide. The partnership will operate under a project-driven framework centred on resource sharing and effective communication. This approach will directly enable the Group to leverage SYSU-IAS's comprehensive laboratory facilities, animal studies supplies resources, especially on non-human primates, and valuable data assets, which are essential for fostering novel drug innovation and the sustainability of the Company's R&D development. The Board considers this strategic partnership establishes a mutually beneficial framework that will drive growth and ensure long-term sustainability. The cooperation is consistent with the Company's development strategy to advance its portfolio of innovative drug candidates.

The Board considers that the Cooperation Agreement provides a valuable opportunity for the parties to leverage their respective resources and expertise and create mutual benefits and synergy for each other. Therefore, the Board is of the view that entering into the Cooperation Agreement is fair and reasonable, and in the interests of the Company and its shareholders as a whole.

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LISTING RULES IMPLICATIONS

As all applicable percentage ratios under Rule 14.07 of the Listing Rules in respect of the commitment of the Company to the Cooperation Agreement were below 5%, the Cooperation Agreement does not constitute a notifiable transaction for the Company under the Listing Rules. In addition, the Cooperation Agreement also does not constitute a connected transaction under Chapter 14A of the Listing Rules. This announcement is being made by the Company on a voluntary basis. Further announcement(s) will be made by the Company in accordance with the Listing Rules as and when appropriate.

By Order of the Board

SinoMab BioScience Limited

Dr. Shui On LEUNG

Executive Director, Chairman and Chief Executive Officer

Hong Kong, 12 August 2025

As at the date of this announcement, the executive director of the Company is Dr. Shui On LEUNG, the non-executive directors of the Company are Dr. Haigang CHEN, Mr. Xun DONG, Ms. Xiaosu WANG and Dr. Jianmin ZHANG and the independent non-executive directors of the Company are Mr. George William Hunter CAUTHERLEY, Mr. Ping Cho Terence HON, Dr. Chi Ming LEE, Ms. Chi Sau Giselle LEE and Mr. Nan SHEN.

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