UCL HUNTINGTON’S DISEASE RESEARCH
HORIZON (DIMEBON) TRIAL
About the study
HORIZON was a phase 3 clinical trial primarily looking at the effect of dimebon (latrepirdine) on cognitive function in mild-to-moderate Huntington’s disease. It was the first large clinical trial to focus on the cognitive aspects of HD and was a global collaboration between the European Huntington’s Disease Network (EHDN) and Huntington Study Group (HSG), supported by Medivation Inc, and Pfizer Inc.
Latrepirdine (dimebon) is an antihistaminic drug that was first used to treat allergies in the 1980’s. Recently, latrepirdine has been shown to enhance survival of brain cells and improve learning and memory in early phase studies of Alzheimer’s disease (AD) and Huntington’s disease (HD).
The HORIZON trial aimed to compare dimebon 20mg three times daily with placebo (no drug) and was double-blind, so neither investigator or participating subjects knew which treatment arm they were assigned to. The following global regions took part in the HORIZON trial:
- North America (30 sites)
- Australia (3 sites)
- Europe (26 sites; 8 countries)
Unfortunately in April 2011, it was announced that Dimebon had failed to demonstrate improvement in thinking and memory among study participants taking Dimebon 60 mg/day.
Offical press release of Pfizer and Medivation on the outcome of the Horizon trial.
HDBuzz has produced a plain-language summary of the results of the HORIZON trial.