Pfizer, Medivation Announce Discontinuation of Huntington Drug Trial
Medivation Chief Executive Officer David Hung MD has announced that the company, along with partner Pfizer Inc, will halt the HORIZON trial, a study of the drug dimebon (latrepirdine) in patients with Huntington disease. The Phase III trial has failed to show statistically significant improvement in patients over those taking a placebo.
Huntington disease is a genetic disorder caused by a defect on chromosome 4 which causes a degeneration of nerve cells in the brain. Symptoms include progressive dementia, behavioral changes, and abnormal and unusual movements. Currently there is no cure for the disease and no known way to stop it from worsening.
In a press release, Medivation states that dimebon did not achieve statistical significance for either of the co-primary endpoints, the Mini-Mental State Examination (MMSE) which measures cognition, or the Clinician’s Interview-Based Impression of Change plus caregiver input (CIBIC-plus) which measures global function.
The double-blind, placebo-controlled study had enrolled 403 patients with Huntington disease at 64 sites in North America, Europe and Australia. Patients were randomized to receive either 20 mg of dimebon three times daily or a placebo for six months.
In preclinical studies, dimebon was shown to protect brain cells from damage and enhance brain cell survival, potentially by stabilizing and improving mitochondrial function.
"We are disappointed with the results of the HORIZON trial, given the high unmet need in this patient population. At this point, we will discontinue development of dimebon in Huntington disease, including the ongoing open-label extension study," said Dr. Hung.
Dr. Steve Romano, senior vice president and Medicines Development Group head, notes that the results of the HORIZON trial will be presented at an upcoming medical meeting.
Dimebon is currently in another late-stage trial named CONCERT for patients with mild-to-moderate Alzheimer’s disease. This trial will continue with results expected in early 2012.
Sources Include: Medivation News Release and PubMed Health