GENFLEET-B - VOLUNTARY ANNOUNCEMENT

Preclinical Research Data of Three Large- and Small-molecule Targeted Therapies Relevant to RAS Pathway to Be Presented at 2026 AACR Annual Meeting

GenFleet Therapeutics (Shanghai) Inc.

勁方醫藥科技(上海)股份有限公司

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

(Stock Code: 2595)

VOLUNTARY ANNOUNCEMENT

Preclinical Research Data of Three Large- and Small-molecule Targeted Therapies

Relevant to RAS Pathway to Be Presented at 2026 AACR Annual Meeting

This announcement is made by GenFleet Therapeutics (Shanghai) Inc. (the "Company" or "GenFleet", together with its subsidiaries, the "Group") on a voluntary basis to inform the shareholders and potential investors of the Company about the latest business updates of the Group.

The board of directors of the Company (the "Board") is pleased to announce that the Company will exhibit preclinical research data of three compounds - GFH276 (nondegrading molecular glue), GFS784 (novel antibody-drug conjugate linking functional antibody with synergistic targeted payload) and GFH603 (molecular glue-like covalent allosteric activator) - at the poster presentation of the 2026 AACR Annual Meeting. The Company's RAS-targeted matrix encompasses multiple selective and Pan RAS inhibitors, as well as targeted therapies for potential co-mutations associated with the RAS pathway; this matrix includes large- and small-molecule targeted therapies relevant to RAS pathway with diversified modalities and mechanisms. This AACR Annual Meeting is scheduled to take place in San Diego, US from April 17 to 22, 2026. The Company's selected posters will be exhibited on April 19 and April 21 respectively. Please refer to the Company's website www.genfleet.com for more details.

About the Company

The Company is a biopharmaceutical company based in China focusing on bringing new and effective treatment options in the fields of oncology, autoimmune and inflammatory diseases to uphold our mission of addressing unmet medical needs around the globe. The Company adheres to an innovative development strategy, with a vision to propel us with the advancement of science and technology to build a globally competitive biopharmaceutical company. The Company has established and leveraged a proven, integrated research and development platform spanning target discovery, molecular discovery and evaluation, translational science and clinical development, as well as key manufacturing aspects including formulation research, process development and quality analysis. Our technological capabilities include discovery of new molecular entities, novel molecular modalities, investigation of molecular process routes and quality standards, as well as exploration of differentiated clinical development strategy and pathway. Combining these internally accumulated capabilities and external resources of our collaborators and service providers, the Company has rendered our pipeline products among the frontrunners in both China and the global market, resulting in potentially significant market opportunities and commercial value.

Forward-looking Statements

Specific information in this press release may contain or constitute forward-looking words that are not historical facts. They can be identified by using forward-looking terminology, such as "predict", "believe", "plan", "forecast", "expect", "will", "may", "should" and other words of similar meanings. Based on the management's current beliefs, plans, estimates and expectations of the company's operation and market trends subject to changes beyond control, the forward-looking terminology reflects GenFleet Therapeutics' beliefs, plans, estimates and expectations of future development. Actual outcome in the future may differ significantly from forward-looking words owing to market, policy, and R&D uncertainties, among others. Subject to the above-mentioned uncertainties, GenFleet Therapeutics makes no expressed or implied guarantee as to the accuracy, completeness or feasibility of this presentation, and you are cautioned not to solely rely on such forward-looking words. Neither the company nor any of its directors, officers, employees, shareholders, agents, related parties, consultants or representatives will be liable to you or any other person for consequences resulting from using this presentation. Investors are advised to exercise due diligence with reference to the company's official disclosures for decision-making.

GLOSSARY OF TECHNICAL TERMS

"AACR" American Association for Cancer Research

"RAS" ras sarcoma, a family of proteins that are critical regulators of cellular signaling pathways; it primarily includes

HRAS, KRAS, and NRAS

Cautionary Statement required by Rule 18A.05 of the Rules Governing the Listing

of Securities on The Stock Exchange of Hong Kong Limited: The Company cannot guarantee that it will be able to develop, or ultimately market, GFH276, GFS784, GFH603, successfully. Shareholders and potential investors of the Company are advised to exercise caution when dealing in the shares of the Company.

By order of the Board

GenFleet Therapeutics (Shanghai) Inc. Dr. Qiang LU

Chairman and Executive Director

Hong Kong, March 20, 2026