MDA 2025: Advancing Care in DMD and SMA

Panelists discuss how recent advancements in muscular dystrophy treatment have evolved toward truly disease-modifying therapies using gene replacement, antisense oligonucleotides, and gene transfer technologies, while highlighting the ongoing challenges of identifying at-risk populations and collecting comprehensive safety and efficacy data.

Panelists discuss how data from MDA 2025 demonstrate that delandistrogene moxeparvovec (gene therapy for DMD) shows statistically significant improvements in motor function outcomes including North Star Ambulatory Assessment, time to rise from floor, and 10-m walk/run compared with external control groups over 2 years of treatment.

Panelists discuss how the pooled 3-year data for delandistrogene moxeparvovec show sustained motor function stabilization and less deterioration compared with natural history, providing confidence in the therapy’s long-term benefits while acknowledging the need for survival data and addressing concerns about potential transgene dilution over time.

Panelists discuss how spinal muscular atrophy is an autosomal recessive genetic disease affecting motor neurons with 3 currently approved disease-modifying therapies that restore SMN protein expression, including 2 requiring ongoing treatment and 1 gene transfer therapy (onasemnogene abeparvovec) approved only for patients under 2 years of age.

Panelists discuss how gaps in SMA care persist despite highly effective treatments, particularly regarding racial and ethnic disparities in research participation and global access challenges due to high costs and infrastructure limitations in developing countries.

Panelists discuss how intrathecal delivery of onasemnogene abeparvovec in the STEER study demonstrates statistically significant motor function improvements in older patients with SMA (ages 2-18 years) with favorable safety profiles, potentially expanding gene therapy access beyond the current age restriction of under 2 years.

Panelists discuss how exciting ongoing research efforts are expanding similar gene therapy technologies to other muscular dystrophies like FSHD and myotonic dystrophy, using strategies to knock down rather than restore gene expression for these autosomal dominant conditions.

Panelists discuss how patient perspectives on new therapies center around clinically meaningful outcomes and survival while balancing individual risk tolerance, with some patients willing to accept higher risks for potentially transformative treatments in devastating diseases.

Panelists discuss how payers seek good return on investment when evaluating expensive gene therapies, creating potential friction when innovative treatments come at significant costs, requiring ongoing dialogue between manufacturers, patients, payers, and physicians to determine appropriate value and access.