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Genflow Biosciences Plc

Genflow Completes Dosing Phase of Canine Gene Therapy Trial
No Adverse Events Reported During Administration

Genflow Biosciences Plc (LSE: GENF) (OTCQB: GENFF) ("Genflow" or the "Company"), a biotechnology company focused on extending healthspan through advanced gene therapies, today announced that all dogs enrolled in its ongoing clinical trial have successfully received the full administration of the Company's investigational SIRT6-based gene therapy.

Importantly, no adverse events were reported during the dosing phase of the study. No serious, moderate, or minor side effects were observed, demonstrating a strong safety and tolerability profile for the therapy.

The study is being conducted as a blinded clinical trial and, as such, efficacy outcomes cannot yet be assessed. Genflow expects a first efficacy read in mid-to-late January 2026, which will include blood analyses and muscle biopsies to evaluate potential therapeutic benefits related to sarcopenia, overall healthspan, and lifespan-associated biomarkers.

The dogs enrolled in the trial will continue to be monitored for a total duration of 180 days. A second efficacy assessment is planned at the six-month timepoint, with results expected in June-July 2026, to evaluate durability and longer-term effects of the gene therapy.

Following analysis of the efficacy data, Genflow intends to resume discussions with several animal health companies, including parties currently engaged under confidentiality and data access agreements, to explore potential early-stage licensing opportunities.

Dr. Eric Leire, CEO of Genflow, commented: "These milestones represent an important step forward for our longevity program. The absence of any adverse events is highly encouraging and reinforces the strong safety profile of our approach. We look forward to sharing initial efficacy data in the coming months as the study progresses."

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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 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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