Santhera Pharma completes enrollment in phase IV (LEROS) study of Raxone to treat Leber's hereditary optic neuropathy

Santhera Pharmaceuticals announces that it has completed patient enrollment in the ongoing Phase IV study (LEROS) with Raxone (idebenone) for the treatment of Leber's hereditary optic neuropathy (LHON). Results from the 24-month active treatment study conducted in 31 study centers in Europe and the USA are expected in 2021. LEROS is a Phase IV, external natural history controlled, open-label intervention study to further assess the efficacy and safety of long-term treatment with Raxone in patients with LHON (ClinicalTrials.gov Identifier: NCT02774005). Patients were eligible for enrolment up to five years after the initial onset of symptoms of vision loss and were stratified according to their time since onset of vision loss to investigate the influence of disease duration on treatment efficacy. The primary objective of the trial is to assess the efficacy of Raxone to improve or stabilize visual acuity (VA) in patients starting treatment up to one year after the onset of vision loss, compared to an external natural history control group. Following a pre-planned sample size recalculation, the study has now completed recruitment with 197 patients enrolled. Study participants are treated with Raxone (150 mg idebenone tablets, daily dose of 900 mg) for 24 months. Santhera is conducting the LEROS trial in 31 study sites across nine European countries and the USA and expects to complete the study by the second quarter 2021.

The LEROS study builds on the results from the double-blind, randomized, placebo-controlled RHODOS trial and data from an Expanded Access Program which demonstrated clinically meaningful outcomes of Raxone treatment for patients with LHON . Treatment benefit manifests as a clinically relevant stabilization (CRS) or a clinically relevant recovery (CRR) of visual acuity or both.

Comment: In September 2015, the European Commission granted a marketing authorization valid throughout the European Union for Raxone for the treatment of visual impairment in adults and adolescents with LHON. With approval under exceptional circumstances, several specific obligations - including the LEROS study - were agreed with the European Medicines Agency to further assess the efficacy and safety under routine use and longer term treatment.