Unmet Therapeutic Needs of Non-Ambulatory Patients with Duchenne Muscular Dystrophy: A Mixed-Method Analysis

Duchenne muscular dystrophy has been a launching pad for patient-focused drug development (PFDD). Yet, PFDD efforts have largely neglected non-ambulatory patients. To support PFDD efforts in this population, we primarily sought to understand the needs of non-ambulatory Duchenne patients and, secondarily, to examine these needs in the context of the PUL-PROM-a validated patient-reported outcome measure of upper limb functioning.

Non-ambulatory Duchenne patients or their caregivers from eight countries answered open-ended survey questions about patients' needs related to their most significant symptoms and important benefits of new treatments. The PUL-PROM was used to evaluate patients' upper limb functioning and was compared to data collected on non-ambulatory stage and quality of life. We thematically analyzed open-ended data, descriptively analyzed close-ended data, and compared themes by non-ambulatory stage.

The study included 275 participants. Mean patient age was 24. Most patients were early-stage non-ambulatory (67%). Thematic analysis identified three congruent themes between significant symptoms and important benefits of new treatments: muscle functioning, especially upper limb function; body system functioning; and quality of life. Muscle functioning and body system functioning were endorsed more frequently in responses from early- and late-stage patients, respectively. Mean PUL-PROM total score was 22 with higher scores in early-stage patients (p ≤ 0.001). Upper limb function positively correlated with quality of life (r = 0.42, p ≤ 0.001).

Non-ambulatory Duchenne patients want new treatments that improve upper limb functioning and body system functioning, and not exclusively regaining ambulation. The PUL-PROM can be used as a patient-centric measure that accounts for the needs of later-stage Duchenne patients.