Pfizer Inc announced results from two phase-1 safety studies, one of PF-04360365, a humanized anti-amyloid monoclonal antibody (mAb), and another of dimebon (latrepirdine) in combination with donepezil HCl tablets, in patients with Alzheimer's disease. Based on the phase-1 study results, PF-04360365 has advanced into phase-2. Dimebon (latrepirdine), being co-developed by Pfizer and Medivation Inc, is in phase-3 development. These data were presented at the Alzheimer's Association 2009 International Conference on Alzheimer's Disease (ICAD) in Vienna, Austria.

A phase-1, single-dose, dose escalation study (0.1 to 10 mg/kg) showed that the investigational compound PF-04360365 was well-tolerated in all patients, with no clinical or imaging evidence of vasogenic edema, and no new microhemorrhage or encephalitis reported to date in the ongoing follow-up period. In the phase-1 dimebon (latrepirdine) study, results from a four-week, placebo-controlled trial of 24 patients on a stable dose of donepezil for at least 60 days showed that dimebon (latrepirdine) was well-tolerated when used in combination with donepezil. Alzheimer's disease, a progressive and degenerative brain disease, is the most common type of dementia. Worldwide societal costs associated with dementia were estimated to be $315.4 billion in 2005.

"Alzheimer's disease is a destructive illness and Pfizer is committed to lifting the burden of the disease on patients and those who care for them," said Steven J Romano, vice president, Medical Affairs Head for Pfizer's Primary Care Business Unit. "We are continuing to work with the global Alzheimer's community to advance research in Alzheimer's disease and currently have an investigational compound, dimebon (latrepirdine), in phase-3 and two other compounds in phase-2."

"We are encouraged by these preliminary safety results and look forward to studying the safety, as well as the efficacy, of PF-04360365 in phase-2 multiple dose trials," said Martin M Bednar, senior director and Pfizer clinical lead for the PF-04360365 programme. "As we explore multiple compounds and mechanisms to treat Alzheimer's disease, safety is of paramount importance given the vulnerability of the elderly population afflicted."

Dimebon (latrepirdine) is an investigational compound for the treatment of Alzheimer's disease.