Voyager Therapeutics Presents Three-Month GLP Toxicology Data for VY1706

Voyager Therapeutics presented three-month good laboratory practice, or GLP, toxicology data for VY1706, the Company's investigational tau silencing gene therapy for Alzheimer's disease, or AD, in a late-breaking presentation at the American Society of Gene & Cell Therapy's 2026 Annual Meeting in Boston, May 11-15. Data presented showed that VY1706 was well tolerated, with no adverse clinical pathology or histopathological findings up to the highest dose tested, and reduced tau protein up to 64% in key brain regions of non-human primates, or NHPs, at 13 weeks following a single IV dose. Voyager's FDA investigational new drug, or IND, application process for VY1706 is on track for Q2 2026 to support projected first-in-human dosing in AD patients in H2 2026. Intravenous delivery of VY1706, a CNS penetrant AAV gene therapy for Alzheimer's disease, demonstrates compelling pharmacology and safety in a 3-month GLP toxicology study in NHPs. VY1706 delivered a potent vectorized MAPT siRNA with broad central nervous system, or CNS, distribution via a single IV dose, using ALPL as its primary blood-brain barrier, or BBB, receptor. 3-month GLP toxicology data for VY1706 demonstrated a favorable tolerability profile with no adverse findings up to the highest dose tested. Treatment with VY1706 resulted in dose-dependent reductions of up to 51-75% MAPT mRNA and 48-64% tau protein in key brain regions at 13 weeks in NHPs. Data from Voyager's seven additional oral and poster presentations at ASGCT demonstrate continued capsid innovation via muscular and neuromuscular targeting, immune evasion, and manufacturability. Directed evolution of muscular and neuromuscular capsid variants in both mice and non-human primates. Voyager leveraged its TRACER platform to develop novel AAV9-based capsids with significantly increased muscle tropism over AAV9 in both mice and NHPs. In mice, the top muscle-targeted capsid achieved 100X increased expression over AAV9 in skeletal muscle and 10X increased expression in heart muscle. In NHPs, the top muscle-targeted capsid achieved 25-30X increased expression over AAV9 in skeletal muscle and 13X increased expression in heart muscle. Voyager generated neuromuscular capsids with features of both muscle and brain capsids, achieving comparable transduction levels to top muscle and brain capsids in NHPs while demonstrating significantly reduced liver exposure relative to AAV9. Intravenous delivery of a bi-functional AAV gene therapy to reduce endogenous ApoE4 and express ApoE2 in ApoE4 humanized mice. A novel BBB-penetrant capsid delivering a bi-functional payload significantly reduced endogenous ApoE4 while achieving expression of ApoE2 at physiological levels following single dose IV-delivery in murine studies. Engineering an AAV9-derived muscle-tropic capsid to evade pre-existing human neutralizing antibodies. A next-generation "stealth" capsid was able to evade pre-existing neutralizing antibodies while retaining muscle tropism, potentially increasing the number of patients eligible to receive muscle-targeted AAV gene therapies. Leveraging artificial intelligence to design AAV mutant capsids optimized for antibody evasion. Novel AAV capsid variants, generated using advanced AI models, showed improvements in antibody evasion, while maintaining favorable manufacturing and CNS-transduction properties. Exploiting an AAV capsid specific receptor to develop stable cell lines for transduction based assays for gene therapies. Cell lines overexpressing a receptor associated with Voyager's TRACER capsids overcome the challenge of lower transduction efficiency observed for engineered capsids in cell-based assays. Evaluating affinity chromatography media for capture of novel blood-brain-barrier penetrant AAV capsids. Optimized transfection platform with improved productivity and transgene packaging for scalable rAAV production.