8 April 2026

Genflow Biosciences Plc

Genflow Reports Sustained Safety and Efficacy Three Months Post Dosing in SLAB Trial

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, highlights continued positive safety and efficacy signals from its ongoing SLAB (Sarcopenia and Longevity in Aged Beagles) clinical trial evaluating its proprietary SIRT6 centenarian gene therapy.

Follow-up observations conducted three months after the initial dosing period confirm that previously reported improvements have been maintained. No adverse events have been observed, and the therapy continues to demonstrate a favourable safety and tolerability profile in aged dogs.

These findings build on the Company's previously announced interim results (please see the Company's announcement dated 12 February 2026 here) and provide early evidence supporting the durability of the therapy's effects. Improvements across multiple independent endpoints remain consistent with earlier observations, while control animals continue to exhibit expected age-related decline.

The SLAB study remains ongoing, with all dogs continuing to be actively monitored and evaluated. The trial is expected to continue for a further four months, with completion anticipated at the end of July 2026. Additional analyses, including methylation clock (biological age) assessment and muscle histology, are in progress and are expected to provide further mechanistic and quantitative insight into the therapy's impact.

Dr Eric Leire, Chief Executive Officer of Genflow said: "These follow-up observations are important as they extend our understanding beyond initial efficacy and into persistence of effect. The consistency of improvements across multiple functional endpoints, together with the continued absence of safety concerns, strengthens our confidence that SIRT6 gene therapy is delivering a sustained biological impact.

Based on the data observed to date, we believe this supports the positioning of our SIRT6 platform as a potentially disease-modifying approach to addressing age-related decline in companion animals. As the study progresses, we continue to engage with prospective partners across animal health to explore licensing, co-development, and commercialisation opportunities."

Further updates will be provided as additional data becomes available.

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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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