Source: DGNews  |  Posted 2 years ago

By Charlene Laino

BALTIMORE, Md -- October 18, 2009 -- Investigators said that a blinded interim safety analysis did not raise any alarms among patients with Friedreich’s ataxia enrolled in a clinical trial testing the investigate drug idebenone.

“In only 4 of the 213 patients included in the safety analysis were there severe events,” reported Jorg Schulz, MD, Professor of Neurology, University Medical Center, Aachen, Germany, in his presentation here on October 13 at the American Neurological Association 134th annual meeting.

The interim analysis was conducted in June 2009. As of the end of July, 18 patients had withdrawn from the trial: 6 due to adverse events, 2 because of pregnancy, and 10 for various other reasons, including withdrawal of consent.

The 5 serious events experienced by the 4 patients were supraventricular extrasystole, reduced visual acuity, fatigue, anxiety and flatulence/abdominal discomfort. “No safety signals have been observed in electrocardiograms, vital signs, or laboratory test results,” Dr. Schulz said during his poster presentation.

Friedreich’s ataxia is a rare autosomal recessive disorder characterised by progressive neurological and cardiac symptoms. The primary neurological symptom is decreased coordination of muscle movement; the heart symptom is hypertrophic cardiomyopathy.

Dr. Schulz explained that idebenone, a short-chain analogue of ubiquinone, may be able to moderate the underlying causes of Friedreich’s ataxia through its antioxidant activity and its role as an electron carrier in the respiratory chain to promote mitochondrial adenosine triphosphate production. Adenosine triphosphate production is reduced in patients with Friedreich’s ataxia.

The year-long phase 3 trial of idebenone (also known as SNT-MC17) is underway in Europe among children (>=8 years) and adults. The phase 3 study enrolled 232 patients who were assigned to placebo or to 1 of 3 doses of idebenone: 180 mg/day, which could be increased to 350 mg/day if the patient weighed at least 45 kg; 450 mg/day, up to 900 mg/day; and 1,350 mg/day, up to 2,250 mg/day.

The ongoing trial remains blinded. The most frequent adverse event among the 213 evaluable patients was headache, reported in 21 of the patients. Other reported adverse events: nausea (n = 19), diarrhoea (n = 18), vomiting (n =9), abdominal pain (n = 8), upper abdominal pain (n = 7), fatigue (n = 5), hypercholesterolaemia (n = 5), rash (n = 5), flatulence (n = 3), and pruritus (n = 3).

The study was supported by Santhera Pharmaceuticals Ltd., Liestal, Switzerland.

[Presentation title: SNT-MC17/Idebenone to Treat Friedreich’s Ataxia: Preliminary Phase 3 Safety Data. Poster T-80]