22 January 2013. In the January JAMA Neurology, researchers formally published the results of the Phase 3 trial of Dimebon®, aka latrepirdine, in Huntington’s disease patients. In April 2011, the drug’s sponsors, Medivation Inc. and Pfizer, announced that Dimebon failed to show efficacy in the six-month HORIZON trial, which enrolled 403 people with Huntington’s disease in 11 countries (see ARF related news story). The drug had shown hints of cognitive benefit in a Phase 2 trial (see ARF related news story), but in Phase 3, people taking Dimebon showed no improvement over controls on the Mini-Mental State Examination or the Clinician Interview-Based Impression of Change. The Huntington Study Group and the European Huntington’s Disease Network carried out the trial.
The findings echo Dimebon's tribulations in Alzheimer’s disease, where promising Phase 2 results (see ARF related news story) evaporated in Phase 3 (see ARF related news story; ARF news story).––Madolyn Bowman Rogers.
HORIZON Investigators of the Huntington Study Group and European Huntington’s Disease Network. A randomized, double-blind, placebo-controlled study of latrepirdine in patients with mild to moderate Huntington disease. Arch Neurol. 2012 Oct 1:1-9. Abstract