Comparing Clinical Outcomes of Different Corticosteroid Regimens for Treating Duchenne Muscular Dystrophy

The results of a randomized clinical trial published in JAMA found that daily corticosteroid regimens of prednisone and deflazacort were more effective in improving clinical outcomes in boys with Duchenne muscular dystrophy (DMD) compared to an intermittent prednisone regimen, supporting the use of daily corticosteroids as initial treatment. 

Health experts recommend corticosteroids like prednisone and deflazacort for all DMD patients, but there is uncertainty about the best dosage and long-term effects, leading to the need for a clinical trial comparing the most frequently prescribed regimens. 

A double-blind, parallel-group randomized clinical trial was conducted with 196 boys aged 4 to 7 years (mean age, 5.8 years) who had DMD and had not received corticosteroid treatment before. The trial took place between January 30, 2013, and September 17, 2016, at 32 clinic sites across 5 countries. Over 3 years, the boys were assessed for various outcomes, with the last participant visit occurring on October 16, 2019.  

The participants were randomly assigned to receive either daily prednisone, daily deflazacort, or intermittent prednisone according to specific dosage instructions. The primary outcomes measured included rise from the floor velocity, forced vital capacity, and participant or parent satisfaction with treatment as measured by the Treatment Satisfaction Questionnaire for Medication. Group comparisons were made using a Bonferroni-adjusted significance level of .017. 

Out of the 196 participants, 164 completed the trial. The study found that both daily prednisone and daily deflazacort were more effective than intermittent prednisone for the primary outcome (P < .001 for daily prednisone vs intermittent prednisone using a global test; P=.017 for daily deflazacort vs intermittent prednisone using a global test). However, there was no significant difference between the effectiveness of the daily prednisone and daily deflazacort regimens (P=.38 for daily prednisone vs daily deflazacort using a global test).  

The differences observed were primarily due to the rise in velocity from the floor velocity (0.06 rise/s [98.3% CI, 0.03 to 0.08 rise/s] for daily prednisone vs intermittent prednisone [P=.003]; 0.06 rise/s [98.3% CI, 0.03 to 0.09 rise/s] for daily deflazacort vs intermittent prednisone [P=.017]; and −0.004 rise/s [98.3% CI, −0.03 to 0.02 rise/s] for daily prednisone vs daily deflazacort [P=.75]).  

The study found no statistically significant differences between the groups in forced vital capacity and TSQM global satisfaction subscale scores. The most common adverse events were abnormal behavior, upper respiratory tract infection, and vomiting. 

“Among patients with DMD, treatment with daily prednisone or daily deflazacort, compared with intermittent prednisone alternating 10 days on and 10 days off, resulted in significant improvement over 3 years in a composite outcome comprising measures of motor function, pulmonary function, and satisfaction with treatment; there was no significant difference between the 2 daily corticosteroid regimens,” said researchers. “The findings support the use of a daily corticosteroid regimen over the intermittent prednisone regimen tested in this study as initial treatment for boys with Duchenne muscular dystrophy.”  

Reference  

Guglieri M, Bushby K, McDermott MP, et al. Effect of different corticosteroid dosing regimens on clinical outcomes in boys with Duchenne muscular dystrophy: a randomized clinical trial. JAMA. 2022;327(15):1456–1468. doi:10.1001/jama.2022.4315