A Multicenter Double-Blind Randomized Trial of Deflazacort Ver- sus Prednisone in Duchenne Muscular Dystrophy: Analysis after 2 Years

We have conducted a double-blind, randomized, multicentric trial in 18 Duchenne muscular dystrophy (DMD) boys, whose age ranged from 5.2 to 14.6 years (mean 7.3 yrs) for treatment with either deflazacort (0.9 mg/kg/day) or prednisone (0.75 mg/kg/day). To reduce side effects after one year the treatment schedule was switched to an alternate day regimen. The two groups were randomized and stratified on the basis of age and functional score at the onset of treatment. We followed the patients every 3 months in the first year and then every four months, evaluating MRC scale in four limb muscles, two in the right upper limb (deltoid and triceps) and two in the right lower limb (ileopsoas and quadriceps femoris) and performance of four functions (walking for 10 meters, climbing stairs, Gowers’ manoeuvre, and rising from a chair). We evaluated the differences in MRC and functional score with respect to baseline. Statistical significance was calculated by the Mann-Whitney test. Side effects were monitored by a questionnaire and by routine blood examination (serum creatine kinase, glucose, ions, hematocrit and complete blood count) and weight and height were recorded at each visit. Change in body weight was evaluated with the student t-test. After 24 months there were 2 drop out patients in the deflazacort group and 3 in the prednisone group for loss of independent ambulation. The two steroids were equally effective improving motor function and functional performances in the first 6 months and then we observed a slow down in the course of the disease. At 9 months, the average weight increase respect to baseline value was 5% (2 Kg) in the deflazacort group and 18% in the prednisone group (p< 0.005) and after 24 months it was 19% in the deflazacort group and 41% in the prednisone group. Only 3 patients on deflazacort had an increase in body weight that exceeded 20% with respect to baseline, but all the remaining patients in the prednisone group had an increase in body weight of over 20%. Two fractures occurred in the deflazacort group. Bone formation and growth evaluated with X-ray of the left hand for bone age did not appear different in the two groups. Eye examination revealed a slight cataract in 3 patients in the deflazacort group and in 1 in the prednisone group. Other minor and slight side effects such as behavioural changes, increased appetite and cushingoid appearance were observed in both groups. Steroid treatment with deflazacort appears to cause less side effects than prednisone, particularly on weight gain, which could be important to maximize motor performances and to avoid long term complications such as spinal deformity and respiratory fatigue.