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Genflow Biosciences Plc

Positive Preliminary Interim Results from SLAB Clinical Trial of SIRT6 Gene Therapy in Aged Dogs

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, announces positive preliminary interim results from its SLAB (Sarcopenia and Longevity in Aged Beagles) clinical trial evaluating its proprietary SIRT6 centenarian gene therapy in aged dogs.

Trial overview

The randomised, blinded study, conducted by an independent contract research organisation, enrolled 24 beagle dogs aged over 10 years who were allocated to four groups: two naked DNA treatment cohorts at different dose levels, a single-dose AAV8 cohort, and a control group.

The interim analysis reflects outcomes observed during the dosing period. Additional endpoints remain under assessment.

Preliminary interim results

All treatment groups demonstrated superior survival compared to the control group during the dosing period. No adverse events were observed, and all treatment modalities exhibited a favourable safety and tolerability profile suitable for use in aged companion animals.

Across treatment cohorts, improvements were observed in several functional and observable endpoints, including quality of life, muscle mass preservation, frailty index reduction, and coat quality, relative to control animals, which exhibited expected age-related decline.

Ongoing analyses

Several key endpoints remain under evaluation, including biological age determination using methylation clock analysis and comprehensive muscle biopsy histology. These analyses are intended to provide further mechanistic and quantitative validation of the therapy's effects. The Company expects to provide a comprehensive update on all remaining endpoints within approximately two months.

Commercial and strategic implications

Genflow believes these preliminary results support the potential of its SIRT6 gene therapy as a first-in-class approach to addressing age-related decline in companion animals and reinforce the programme's relevance to prospective animal health partners. The Company is actively engaging with animal health companies regarding potential licensing, co-development, and commercialisation opportunities.

Dr Eric Leire, Chief Executive Officer of Genflow Biosciences said: ""These preliminary interim results represent a significant milestone for Genflow and significantly strengthen our position for animal health partnerships. The consistency of positive signals across multiple independent endpoints from survival and quality of life to measures of muscle preservation and frailty reduction, combined with an excellent safety profile, supports our SIRT6 platform as a credible, differentiated asset for the companion animal market.

Based on these encouraging preliminary findings, we are proceeding with the follow-up phase to assess durability of effects and to monitor for differences in age-related disease emergence - data that will inform future commercial discussions. We expect to provide a comprehensive update on all endpoints, including the critical methylation clock and muscle histology data, within two months."

Contacts

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 12-month proof-of-concept clinical trial evaluating their 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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