Introduction: Duchenne muscular dystrophy (DMD) is a genetic disorder associated with progressive muscle degeneration due to lack of dystrophin. Current treatment options can delay disease progression, but are non-curative, and many are largely mutation/exon specific. Here, we describe real-world treatment patterns for ambulatory and non-ambulatory DMD patients.
Methods: Data were drawn from the Adelphi DMD Disease Specific Programme™, a cross-sectional survey with retrospective data collection of physicians and their DMD patients conducted in the United States (US) from October 2022 – September 2023. Physicians completed online questionnaires for consecutive consulting DMD patients, reporting demographics, treatment history and satisfaction, and ambulatory status. Analyses were descriptive.
Results: Neurologists provided data on 235 male DMD patients. Mean [standard deviation; SD] patient age was 13.6 [7.3] years and 71% were ambulatory. Overall, 87% of ambulatory and 88% of non-ambulatory patients were prescribed treatment. Treatment was commonly mutation-specific medication (overall: 34%; ambulatory: 32%; non-ambulatory: 41%) or prednisone/prednisolone (overall: 29%). Mean [SD] time on a mutation-specific regimen was 3.2 [3.5] years (ambulatory: 2.5 [2.7] years; non-ambulatory: 4.6 [4.7] years). To manage symptoms, 41% of patients (ambulatory: 32%; non-ambulatory: 66%) were prescribed ≥1 additional medication (e.g., bisphosphonates). Side effects with current regimen were experienced by 72% of patients (ambulatory: 69%; non-ambulatory: 79%). Since treatment initiation, ambulation had “worsened”/“remained the same” for 34% of patients (ambulatory: 24%; non-ambulatory: 59%). Neurologists reported dissatisfaction/neutrality with current regimen for 25% of patients (ambulatory: 19%; non-ambulatory: 36%). Diminishing efficacy was the key neurologist-reported reason for lack of treatment satisfaction (40%).
Conclusion: One third of DMD patients did not achieve a delay in loss of ambulation despite prescribed treatment. Side effects were common and diminishing efficacy was a key reason for dissatisfaction with therapy. Combined with neurologist dissatisfaction, this highlights the need for long-term, well-tolerated treatment that can delay disease progression.