In this study population, treatment with alglucosidase alfa was associated with improved walking distance and stabilization of pulmonary function over an 18-month period. (ClinicalTrials.gov number, NCT00158600.)

Whyte, Michael P.; McAlister, William H.; and et al, ,"Enzyme-replacement therapy in life-threatening hypophosphatasia." The New England Journal of Medicine.366,10. 904-913. (2012).

Measurements of muscle strength in clinical trials of Duchenne muscular dystrophy have relied heavily on manual muscle testing (MMT). The high level of intra- and interrater variability of MMT compromises clinical study results. We compared the reliability of 12 clinical evaluators in performing MMT and quantitative muscle testing (QMT) on 12 children with muscular dystrophy. QMT was reliable, with an interclass correlation coefficient (ICC) of >0.9 for biceps and grip strength, and >0.8 for quadriceps strength. Training of both subjects and evaluators was easily accomplished. MMT was not as reliable, and required repeated training of evaluators to bring all groups to an ICC >0.75 for shoulder abduction, elbow and hip flexion, knee extension, and ankle dorsiflexion. We conclude that QMT shows greater reliability and is easier to implement than MMT. Consequently, QMT will be a superior measure of strength for use in pediatric, neuromuscular, multicenter clinical trials.

The objective of this 12-month study was to describe the clinical features of late-onset Pompe disease and identify appropriate outcome measures for use in clinical trials. Assessments included quantitative muscle testing (QMT), functional activities (FAA), 6-min walk test (6MWT), and pulmonary function testing (PFT). Percent predicted values indicated quantifiable upper and lower extremity weakness, impaired walking ability, and respiratory muscle weakness. Significant declines in arm and leg strength and pulmonary function were observed during the study period. The outcome measures were demonstrated to be safe and reliable. Symptom duration was identified as the best predictor of the extent of skeletal and respiratory muscle weakness.

Objective: To perform a double-blind, randomized study comparing efficacy and safety of daily and weekend prednisone in boys with Duchenne muscular dystrophy (DMD). Methods:A total of 64 boys with DMD who were between 4 and 10 years of age were randomized at 1 of 12 centers of the Cooperative International Neuromuscular Research Group. Efficacy and safety of 2 prednisone schedules (daily 0.75 mg/kg/day and weekend 10 mg/kg/wk) were evaluated over 12 months.Results: Equivalence was met for weekend and daily dosing of prednisone for the primary outcomes of quantitative muscle testing (QMT) arm score and QMT leg score. Secondary strength scores for QMT elbow flexors also showed equivalence between the 2 treatment groups. Overall side effect profiles of height and weight, bone density, cataract formation, blood pressure, and behavior, analyzed at 12 months, did not differ between weekend and daily dosing of prednisone. Conclusions:Weekend dosing of prednisone is equally beneficial to the standard daily dosing of prednisone. Analysis of side effect profiles demonstrated overall tolerability of both dosing regimens. Classification of evidence:This study provides Class I evidence that weekend prednisone dosing is as safe and effective as daily prednisone in preserving muscle strength and preventing body mass index increases in boys with DMD over a 12-month period. Neurology Duchenne muscular dystrophy (DMD) is a progressive muscle disorder due to mutations in the dystrophin gene.1,2 Current treatments can slow disease progression, prolonging ambulation, and improving quality of life and survival. [3][4][5] Corticosteroid treatment for DMD 6-12 is recommended by an American Academy of Neurology practice parameter.13 Furthermore, a recently published standard of care review emphasized the benefit of corticosteroids for DMD.14,15 In a large DMD natural history study currently run by the Cooperative International Neuromuscular Research Group (CINRG), 85% of participants are steroid-treated. 16,17 We hypothesized that weekend prednisone dosing would provide equally effective treatment for DMD as standard daily dosing. Furthermore, corticosteroids might be more widely used in DMD if a dosing regimen had fewer side effects, including less weight gain, less effect on linear Editorial, page 416Podcast Scan this code with your smartphone to access this feature CME Scan this code with your smartphone to access this feature