Alzheimer's drug trial results disappoint TRENTON, N.J., Jan. 17 (UPI) -- U.S. drug companies Medivation Inc. and Pfizer Inc. ended the trial for a drug for mild-to-moderate Alzheimer's disease, company officials said. The Phase 3, 12-month global randomized, double-blind, placebo-controlled trial involved 1,003 patients with Alzheimer's disease. Patients on a stable dose of donepezil for at least four months were randomized to one of three treatment groups -- dimebon 20 mg three times per day, dimebon 5 mg three times per day or a placebo. "We are disappointed in the trial results and the implications for Alzheimer's disease patients and their caregivers," Dr. David Hung, president and chief executive officer of Medivation, said in a statement. I would like to extend my sincere thanks to the patients, their physicians and study teams involved in this trial. Medivation and Pfizer said they will discontinue development of dimebon for all indications and will terminate the ongoing open label extension study in Alzheimer's disease. The companies also said they will terminate their collaboration to co-develop and market dimebon, pursuant to the terms of their agreement.