The SIDEROS study is a phase III clinical trial, evaluating the efficacy of investigational drug idebenone compared to placebo, in delaying the loss of respiratory function in patients with DMD receiving glucocorticoid steroids.

Inclusion criteria include:

  • 1

    Males with DMD confirmed by mutation analysis in the dystrophin gene or by substantially reduced levels of dystrophin protein on a muscle biopsy.

  • 2

    10 years of age or older (there is no upper age limit).

  • 3

    Forced Vital Capacity between 30% and 80% of predicted value.

  • 4

    Corticosteroid use for at least 12 months prior to randomization without any dose adjustments in the last 6 months. Boys may be on any dosing regimen of deflazacort/calcort or prednisone/prednisolone.

  • 5

    Pneumonia immunization and annually immunized with inactivated influenza vaccine.

Full eligibility requirements for this study will be assessed at participating study sites.

For more information on the inclusion criteria, please visit ClinicalTrials.gov (NCT#02814019).

Eligible patients will be randomly assigned to one of two treatment groups:

  • 1

    Those who receive idebenone.

  • 2

    Those who receive a matching placebo.

  • Idebenone or the placebo is to be taken orally 3 times a day for 18 months. Trial participation will last approximately 21 months, and require approximately 10 visits to the study site.

A total of 266 boys and men with DMD taking glucocorticoid steroids will participate in the trial.

All patients completing the last visit will be able to participate in an extension clinical trial (SIDEROS-E) and will receive idebenone until SIDEROS-E is terminated or the marketing authorization is obtained.