Long-term follow-up of hemophilia gene therapy in dogs

Nguyen, G.N., Everett, J.K. et al. Nat Biotechnol. (2020)

Clinical trials evaluating adeno-associated viral (AAV) vector-mediated delivery of factor VIII (FVIII) show promise for the treatment of haemophilia A (HA), but the long-term effects of AAV gene therapy remain unknown.

In a new study, nine dogs with HA were followed for up to a decade after administration of AAV-FVIII vectors. FVIII expression persisted for up to 10 years in AAV-treated dogs, with no evidence of adverse events or malignancy. In two dogs, FVIII levels increased gradually ~4 years after treatment, and liver analysis revealed clonal expansion of cells that had integrated the vector. These findings support the clinical development of AAV gene therapy for HA, but call for additional studies to assess its long-term safety.

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Correspondence to Alexandra Le Bras.

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Le Bras, A. Long-term follow-up of hemophilia gene therapy in dogs. Lab Anim 50, 14 (2021).

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