Single Dose Gene Therapy Shows Promise in Reducing Bleeding Episodes in Haemophilia Patients

In the current study, the most common adverse effect was related to an immune system attack on liver cells that were targeted by the gene therapy, which can render the gene therapy ineffective, if not quickly treated. In the study, affected patients were treated with steroids to limit this immune reaction. Patients in the study will continue to be followed for at least five years to monitor potential long-term side effects.

The new gene therapy only requires a single dose in contrast to the standard therapy and most patients in the study did not need to resume prophylactic factor IX treatments.

“We hear from people born with hemophilia that—even if their disease is well-managed—there’s this burden that’s always in the back of their mind. The frequent infusions, the cost of treatment, the need to plan for infusions when traveling, what happens if they do experience a bleed, and so on, is always there,” Cuker said. “Now that we have patients who were treated on this study and are essentially cured of their hemophilia, they’re telling us about realizing a new, ‘hemophilia-free state of mind.’ As a physician, it’s amazing to see my patients so happy with their new reality.”

Reference: Cuker, A., Kavakli, K., Frenzel, L., Wang, J.-D., Astermark, J., Cerqueira, M. H., Iorio, A., Katsarou-Fasouli, O., Klamroth, R., Shapiro, A. D., Hermans, C., Ishiguro, A., Leavitt, A. D., Oldenburg, J. B., Ozelo, M. C., Teitel, J., Biondo, F., Fang, A., Fuiman, J., McKay, J., Sun, P., Rasko, J. E. J., & Rupon, J. (2024). Gene therapy with fidanacogene elaparvovec in adults with hemophilia B. New England Journal of Medicine, 391(12), 1108-1118. https://doi.org/10.1056/NEJMoa2302982