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10 October 2025

Genflow Biosciences Plc

Update on Animal Health Program

LONDON, UK-Genflow Biosciences Plc (LSE:GENF)(OTCQB:GENFF) ("Genflow" or "the Company"), the only publicly listed longevity company in Europe, is pleased to provide an update on its Dog Aging (GF-1004) study, a proof-of-concept clinical trial evaluating the safety and efficacy of its proprietary SIRT6-centenarian gene therapy for age-related decline in elderly dogs.

Genflow's proprietary centenarian SIRT6 gene therapy has now been administered for the second time in its ongoing randomized, controlled trial involving 28 beagles aged 10 years and older. In March, recipients received three different modalities of SIRT6 gene therapy with no ill or adverse effects observed, while control animals remained untreated. The repeat administration has again demonstrated an excellent safety and tolerability profile, marking a key milestone in the study. The dogs are in a follow-up period expected to conclude in January 2026.

This successful second administration underscores the robustness of Genflow's gene therapy platform and its potential applicability beyond human health. The SIRT6 gene, sourced from human centenarians, plays a vital role in DNA repair, metabolic regulation, and resistance to age-related decline. By leveraging this unique gene variant, Genflow aims to introduce a new class of longevity-based treatments into the multi-billion-dollar global animal health market, targeting improved healthspan, vitality, and lifespan in companion and livestock animals.

Dr. Eric Leire, Chief Executive Officer of Genflow Biosciences, commented: "We're very encouraged by the continued safety validation of our SIRT6 therapy and by the strong engagement we're seeing from established players in the animal health industry. The animal health market represents an attractive near-term commercial opportunity for Genflow, complementing our core human longevity programs while showcasing the broader potential of our gene therapy platform."

With safety confirmed in repeat administration, Genflow will continue to advance its animal health initiative toward the next stage of clinical evaluation and partnership development. The Company remains committed to creating value for shareholders through innovation, collaboration, and leadership in the emerging field of genetic longevity therapeutics.

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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 to decelerate the aging process, 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 results. Genflow's 12-month proof-of-concept clinical trial evaluating their SIRT6-centenarian gene therapy in aged dogs began in March 2025. Other programs planned 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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