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13 April 2026

Genflow Biosciences Plc

International Patent Publication Expands Protection for SIRT6-Based Muscular Disease Program

Genflow Biosciences Plc (LSE:GENF) (OTCQB:GENFF) ("Genflow" or the "Company"), a European-based biotechnology company focused on the development of gene therapies for age-related diseases, is pleased to announce the international publication of its Patent Cooperation Treaty (PCT) application, WO 2026/062177 A1, entitled "Variants of Sirtuin 6 for the Treatment of Muscular Diseases."

The published PCT application relates to variants of SIRT6 for the prevention and treatment of muscular diseases, with particular focus on frailty syndrome and sarcopenia. The application describes compositions and methods involving SIRT6 variants, including nucleic acids, polypeptides, vectors and pharmaceutical compositions intended for use in muscular disease settings associated with loss of muscle mass and altered endocrine function of the muscle.

This international publication represents an important milestone in Genflow's intellectual property strategy and broadens the potential protection surrounding the Company's SIRT6 platform beyond longevity and metabolic applications. By advancing patent coverage into muscular diseases, Genflow is further strengthening the proprietary foundation of its platform while opening additional potential therapeutic pathways for development and partnering.

Strategic Significance

The publication enhances the visibility and scope of Genflow's IP estate at an international level. It supports the Company's strategy of building layered protection around the therapeutic use of SIRT6 variants across multiple age-related indications.  The PCT publication also preserves Genflow's ability to pursue patent protection across multiple jurisdictions, supporting development flexibility and potential discussions with pharmaceutical and biotech partners. Taken together, this publication reinforces the depth of the Company's scientific platform and the continued expansion of its intellectual property backbone.

Dr. Eric Leire, Chief Executive Officer of Genflow Biosciences, commented: "The international publication of this patent application marks another important step in the expansion of Genflow's intellectual property portfolio. By extending our SIRT6 platform into muscular diseases such as frailty and sarcopenia, we are continuing to build strategic protection around areas of high unmet need and significant relevance to healthy ageing. This publication further strengthens our position as we advance the development and potential partnering of our gene therapy platform."

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About Genflow Biosciences

Founded in 2020, Genflow Biosciences Plc. (LSE:GENF) (OTCQB:GENFF), a biotechnology company headquartered in the UK with R&D facilities in Belgium, is pioneering gene therapies for age-related diseases, with the goal of promoting longer and healthier lives while mitigating the financial, emotional, and social impacts of a fast-growing aging global population. Genflow's lead compound, GF-1002, works through the delivery of a centenarian variant of the SIRT6 gene which has yielded promising preclinical results. Genflow's proof-of-concept clinical trial evaluating its SIRT6-centenarian gene therapy in aged dogs began in March 2025. Other programs include a clinical trial that will explore the potential benefits of GF-1002 in treating MASH (Metabolic Dysfunction Associated Steatohepatitis), the most prevalent chronic liver disease for which there is no effective treatments. Please visit www.genflowbio.com  and follow the Company on LinkedIn and X.

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