A daily corticosteroid regimen is more effective than an intermittent prednisone regimen in the initial treatment of boys with Duchenne muscular dystrophy.
An international study from five countries randomised 196 boys aged 4-8 years with Duchenne muscular dystrophy to either daily prednisone (0.75 mg/kg), daily deflazacort (0.90 mg/kg), or intermittent prednisone (0.75 mg/kg) for 10 days on and then 10 days off.
The boys were followed up at three and six months from baseline then every six months until month 36.
The study, published in JAMA, found both daily prednisone and daily deflazacort were both more effective than intermittent prednisone in terms of the composite primary outcome.
The outcome included rise from the floor velocity as measure of motor function, forced vital capacity as a measure of pulmonary function, and participant or parent global satisfaction with treatment measured by the Treatment Satisfaction Questionnaire for Medication (TSQM; score range, 0-100).
“The significant differences between the daily regimens and the intermittent prednisone regimen were principally attributable to the rise from the floor velocity component,” the study said.
Participants in both daily regimen groups also performed significantly better than those in the intermittent prednisone regimen group with respect to all secondary motor function outcomes such as 10-m walk or run velocity.
There were no significant differences between the two daily regimens.
The study said most adverse events, including abnormal behavior (34-38%), upper respiratory tract infections (29-37%), and gastrointestinal issues such as vomiting (23-29%) and abdominal pain (20-29%), were mild and similar between the three groups.
Cataracts were reported more frequently in the daily deflazacort group, weight gain more commonly with daily prednisone, and hypertrichosis was more common in both daily treatment regimens.
Slowing of growth was significantly less severe with intermittent prednisone than with the daily regimens.
The study said corticosteroids were likely to remain the main treatment for boys with Duchenne muscular dystrophy for the foreseeable future and worldwide.
New treatments such as exon skipping and read-through premature stop variant agents were only available for less than a third of patients and were prescribed in combination with corticosteroids.
“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,” the study concluded.