Supplementary materials: Disease progression rates in ambulatory Duchenne muscular dystrophy by steroid type, patient age and functional status

These are peer-reviewed supplementary materials for the article 'The impact of willingness-to-pay threshold on price reduction recommendations for oncology drugs: a review of assessments conducted by the Canadian Agency for Drugs and Technologies in Health' published in the Journal of Comparative Effectiveness Research.

• Supplemental Table 1: Overview of the patients from the placebo arms of DMD clinical trials
• Supplemental Table 2: Baseline characteristics for the pooled placebo arms of the DMD clinical trials who received daily corticosteroids, by clinical trial corticosteroid type
• Supplemental Table 3: Baseline characteristics for the pooled placebo arms of the DMD clinical trials who received daily corticosteroids, by baseline age groups and corticosteroid type
• Supplemental Table 4: Baseline characteristics for the pooled placebo arms of the DMD clinical trials who received daily corticosteroids, by baseline corticosteroid duration and corticosteroid type
• Supplemental Table 5: Baseline characteristics for the pooled placebo arms of the DMD clinical trials who received daily corticosteroids, by baseline timed rise from supine and corticosteroid type
• Supplemental Table 6: Unadjusted change in motor function outcomes from baseline to 12, 24, 36, and 48 weeks among the daily deflazacort and prednisone groups of the DMD clinical trial placebo arms
• Supplemental Table 7: Comparison of change in motor function outcomes from baseline to week 48 between the daily deflazacort and prednisone groups in subgroups of the pooled DMD clinical trial placebo arms

Aim: To examine benefits of corticosteroids for Duchenne muscular dystrophy (DMD) by age and disease progression. Methods: Data from daily steroid users (placebo-treated) were pooled from four phase 2b/3 trials in DMD. Outcomes assessed overall and among subgroups included changes from baseline to 48 weeks in six-minute walk distance (6MWD), timed function tests and North Star Ambulatory Assessment total score. Results: Among 231 patients receiving deflazacort (n = 127) or prednisone (n = 104), observed differences in 6MWD favoring deflazacort over prednisone were significant for patients with relatively older age (≥8-years-old), greater disease progression (baseline timed stand from supine ≥5 s), or longer corticosteroid use (>3 years). Conclusion: Daily deflazacort had greater benefits than daily prednisone particularly among older/more progressed patients.