DELOS Phase III Study with Idebenone (Catena®) in Duchenne Muscular Dystrophy

Aims: Duchenne muscular dystrophy (DMD) shows a progressive course and loss of ambulation around 9 to 10 years of age and respiratory complications frequently cause early morbidity and mortality. Drug therapy with glucocorticoid steroids starting at the age of 5 years has been shown to prolong ambulatory status, to improve cardiopulmonary function, to reduce the risk of scoliosis and to possibly prolong life expectancy. However the side-effect profile of steroids hinder long-term use in DMD patients. Idebenone, a short-chain benzoquinone, acts by reducing oxidative stress and improving electron transfer in the mitochondrial respiratory chain, thereby restoring cellular energy. A phase II study (DELPHI) showed beneficial effects of idebenone on pulmonary function, such as peak expiratory flow (PEF), and myocardial function. The therapeutic effect on pulmonary function was larger in patients not on concomitant steroids compared to steroid-using patients.

Methods: This Phase III DELOS trial is an international, multi-center, double-blind, randomised, placebo-controlled study of the efficacy, safety and tolerability of Idebenone (Catena®) in 10–18 year old patients with DMD. Patients are randomized to receive Catena® (900mg/day) or placebo for 52 weeks. At this stage, DMD-patients currently not using concomitant glucocorticoid steroid therapy are enrolled. The primary objective of the study is to assess the efficacy of idebenone compared to placebo in improving respiratory function or delaying the loss of respiratory function. PEF, the primary efficacy variable, as well as other pulmonary function tests will be assessed during visits. In addition, PEF data will be collected weekly in a home-setting with a hand-held device.

Results: Patient characteristics and study baseline data from pulmonary function tests will be presented and the data from different assessment methods will be compared.

Conclusion: Idebenone could be a helpful therapeutic intervention to improve respiratory function in DMD-patients, particularly in patients not taking glucocorticoid steroids. Study sponsored by Santhera Pharmaceuticals.

Duchenne muscular dystrophy - DELOS study - Idebenone (Catena®)