Introduction: Duchenne muscular dystrophy (DMD) is a rare, X-linked neuromuscular disorder. This observational analysis evaluated the real-world safety of branded deflazacort (Emflaza), the first FDA-approved corticosteroid to treat DMD.
Methods: Deflazacort treatment exposure was estimated using data from the manufacturer (up to October 2023). Adverse event (AE) data for branded deflazacort were obtained from the FDA Adverse Event Reporting System (FAERS) database on December 7, 2025, covering 9 years of data from approval in 2017 to 2025. FAERS collects information on AEs reported by healthcare professionals, consumers and drug manufacturers, but does not collect information on causality, treatment duration or number of patients treated.
Results: Estimated total exposure to branded deflazacort between 2017 and October 2023 was more than 10 000 patient-years. Overall, 6953 AEs in 3369 cases were reported for branded deflazacort from 2017 to 2025; 86.5% of cases were reported by consumers and 13.5% by healthcare professionals, and 24.7% were reported as serious. Reasons for deflazacort treatment included DMD in 42.4% of cases and muscular dystrophy in a further 45.0%; other or unknown conditions were reported in 12.6% of cases. Patient age was available in 600 cases; of these, 43.3% and 39.2% were aged 3–11 and 12–17 years, respectively. The most common individual AEs were increased weight and fall (6.5% and 2.9% of events, respectively). Behavioral and psychiatric AEs accounted for 11.2% of AEs, with the most common being anger (1.4%), abnormal behavior (1.1%) and aggression (1.0%). Fractures accounted for 3.3% of AEs (lower limb, 2.2%; upper limb, 0.3%; vertebral, 0.2%; other/not specified, 0.6%) and cataracts accounted for 0.6%. An updated data cut will be presented in the poster.
Conclusions: This real-world observational analysis suggests that branded deflazacort is extensively used (more than 10 000 patient [exposure] years) and is well tolerated in patients with DMD.