Therapeutic trial of isaxonine in duchenne muscular dystrophy

A randomized double-blind therapeutic trial of isaxonine was completed over a 2-year period for 20 ambulant boys with Duchenne muscular dystrophy aged 5 1/2-10 years. The effect of the drug was monitored by measurement of walking times over 28 and 150 ft, motor ability score, MRC score based on 32 muscle groups, and myometry of 7 muscle groups. The drug had no significant effect on the progression of the disease. The trial had statistical power comparable to previous larger-scale multicenter trials. This reflected the low variability in the patients in relation to the magnitude of the overall deterioration. Measurements of muscle force (myometry and MRC score) had much greater statistical power than measurements of function (motor ability score and walking times) as analyzed by our methods. These observations have important implications for the design of future trials.