European regulators have validated Santhera's marketing application for Raxone as a treatment for certain patients with Duchenne muscular dystrophy.

The group is targeting its treatment to DMD patients with respiratory function decline who are not taking concomitant glucocorticoids.

The filing is based on data from the Phase II (DELPHI) programme and successful pivotal Phase III (DELOS) study, which demonstrated a statistically significant and clinically relevant benefit of Raxone (idebenone) treatment in preserving respiratory function compared to placebo.

These findings were also substantiated by a natural history study showing that the benefit observed in the Raxone-treated group would not have been expected from the natural course of the disease, the firm noted.

Also, it said the marketing authorisation includes recent data showing that patients taking the drug in the DELOS trial had a reduced risk of bronchopulmonary complications including fewer hospitalisations caused by such complications and a reduced need for systemic antibiotic treatment compared to patients receiving placebo.

"The clinical relevance of these findings is supported by the outcome of a patient-centered benefit-risk survey which showed that DMD patients and their caregivers placed a high value on treatments that could reduce pulmonary complications," Santhera said.

Raxone won European approval last year as the first treatment for visual impairment in adolescent and adult patients with Leber's Hereditary Optic Neuropathy (LHON), an inherited mitochondrial disease which, if untreated, usually leads to rapid, profound and permanent blindness.

Santhera expects an opinion from the CHMP on the proposed DMD indication in the first quarter of next year.