Characterization of deflazacort use in young Duchenne muscular dystrophy patients: an analysis of data from the PTC Cares database



Poster Number: T330


Jonathan Blaize, PhD, PTC Therapeutics, South Plainfield, NJ, USA, Alexis Krolick, DNP, PTC Therapeutics, South Plainfield, NJ, USA, Bethany Freel, PhD, PTC Therapeutics, South Plainfield, NJ, USA, Elaine Dong, PharmD, PTC Therapeutics, Gregory Iovine, PTC Therapeutics, South Plainfield, NJ, USA

Duchenne muscular dystrophy (DMD) is a rare, X-linked neuromuscular disorder. Deflazacort is indicated for the treatment of DMD in patients aged ≥2 years in the US and is recommended as a first-line therapy. Evidence demonstrates that early initiation and uninterrupted use of deflazacort translates to clinically meaningful benefits. Evidence gaps remain for corticosteroid use in patients aged <5 years. This study aimed to characterize deflazacort use in patients with DMD aged 2 to <5 years in the US. PTC Cares collects and maintains an internal database of patients using deflazacort in the US. De-identified data were analyzed for patient characteristics, prescription patterns by region (Northeast, West, Midwest, Southeast) and discontinuations. Preliminary analyses of data collected from February 2017 to October 2023 identified 277 patients aged 2 to <5 years at deflazacort referral, 218 of whom were actively receiving deflazacort (active) at the time of analysis. The mean (standard error of the mean [SEM]) age at referral for active patients was 4.1 (0.03) years. For active patients with known ambulatory status at the time of analysis, 93% were ambulatory, 3% were non-ambulatory, and 4% were combination ambulatory/non-ambulatory. The referral rate of active patients aged 2 to <5 years as a proportion of all active patients was highest in the Midwest (9%) and lowest in the Northeast (6%). Of the patients aged 2 to <5 years not receiving deflazacort at the time of analysis (inactive), 23 had discontinued deflazacort. The mean (SEM) age of discontinuation was 6.1 (0.78) years, and the mean (SEM) time from deflazacort referral to discontinuation was 2.2 (0.64) years. These data provide insights into the characteristics of young patients receiving deflazacort in the US and identify discrepancies in referral rates of these patients between regions. Further analyses are ongoing and updated data will be presented in the poster.