Gene therapy for Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked neuromuscular disorder caused by variants of the DMD that leads to progressive muscle degeneration. Recent advances in gene therapy have opened new therapeutic avenues, particularly through the use of adeno-associated virus (AAV)-mediated micro-dystrophin delivery. Delandistrogene moxeparvovec, the first FDA-approved gene therapy for DMD, has demonstrated transgene expression and potential functional improvement in early phase trials, although its long-term efficacy, durability, and safety remain unconfirmed. Immune-mediated toxicities including myositis, myocarditis, and liver injury present significant clinical challenges, prompting the need for careful patient selection, immunoprophylaxis, and post-treatment monitoring. In addition to micro-dystrophin replacement, novel gene therapy approaches such as endogenous dystrophin upregulation, exon skipping, and adjunctive muscle-enhancement strategies are being explored. Future studies focus on overcoming vector size limitations by using dual/triple AAV systems or non-viral platforms, improving muscle tropism through capsid and promoter engineering, and expanding eligibility through desensitization protocols. This review provides an integrated overview of the current progress, challenges, and future perspectives in gene therapy for DMD, with the aim of supporting its safe and effective clinical implementation.