FDA grants Pfizer’s DMD Gene Therapy Fast Track Designation
Duchenne Muscular Dystrophy (DMD) is a rare genetic disorder occurs due to changes in rod-shaped cytoplasmic protein Dystrophin, the protein that keep muscle cells intact. DMD is characterized by progressive degeneration of muscles and thus weakness.
DMD is generally seen in boys. Less than 2,00,000 cases are seen per year in US. Medical diagnosis is needed to ascertain DMD. DMD is chronic and spans for long time, some times the entire life-span. Though there is no treatment as of for DMD but the symptoms associated with it can be cured.
So far FDA has approved Viltepso (Viltolarsen) injection and Vyondys 53 (Golodirsen) injection for the targeted treatment of DMD. To this endeavor, the pharma giant Pfizer focused research on gene therapy for DMD.
Pfizer has developed PF-06939926, is an investigational, recombinant adeno-associated virus serotype 9 (AAV9) capsid carrying a shortened version of the human dystrophin gene (mini-dystrophin) under the control of a human muscle-specific promotor. The AAV9 capsid was chosen as the delivery mechanism because of its potential to target muscle tissue. Pfizer initiated the Phase 1b multi-center, open-label, non-randomized, ascending dose study of a single intravenous infusion of PF-06939926 in 2018. The goal of the study is to assess the safety and tolerability of this investigational gene therapy. Other objectives of the clinical study include measurement of dystrophin expression and distribution, as well as assessments of muscle strength, quality and function.
PF-06939926 was evaluated for safety and efficacy in various trials run by Pfizer in boys. Based on the Phase 1b data provided by Pfizer Inc., the US FDA has accorded Fast Track Designation to the Gene Therapy accompanied with PF-06939926 for DMD. This accordance facilitates the faster development of the therapy that can address the urging need for DMD.
Looking at the near future, it will emerge as the best treatment for Duchenne Muscular Dystrophy!
