EPIX Pharmaceuticals Inc, a biopharmaceutical company focused on discovering and developing novel therapeutics through the use of its proprietary and highly efficient in silico drug discovery platform, has begun its phase 2b programme in Alzheimer's disease through the initiation of a clinical trial of PRX-03140, its novel 5-HT4 agonist, in combination with donepezil (Aricept).

Under the company's collaboration agreement with GlaxoSmithKline (GSK), EPIX is entitled to receive a $7.5 million milestone payment from GSK related to the start of the phase 2b programme for PRX-03140 in Alzheimer's disease. The phase 2b proof-of-concept programme consists of two clinical trials - a six month trial evaluating PRX-03140 in combination with donepezil and a three month trial studying PRX-03140 as monotherapy; the monotherapy trial is expected to begin later in the second quarter.

"This phase 2b programme follows the encouraging results seen in our phase IIa trial, in which monotherapy treatment with PRX-03140 resulted in a statistically significant change from baseline as well as from placebo on the ADAS-Cog score," said Michael G. Kauffman, MD, Ph.D., chief executive officer of EPIX. "While our previous two-week trial was primarily designed to address safety, we were excited by the measurable impact on memory and cognition PRX-03140 had on many of the participating patients. Our data indicate that PRX-03140 stimulates acetylcholine release and production in the brain without the peripheral, dose-limiting side effects commonly seen with cholinesterase inhibitors. There remains a significant unmet need for Alzheimer's disease drug therapies that will improve symptoms with minimal side effects".

"We are encouraged by the PRX-03140 data we've seen to date, and based upon this, we are pleased to see EPIX begin the phase IIb programme with PRX-03140 in Alzheimer's disease," said Hugh Cowley, MD, head of GSK's Centre of Excellence for External Drug Discovery (CEEDD). "We believe that patients with Alzheimer's disease may ultimately be treated with combination therapy to manage the progression of the disease and to manage effectively the symptoms of Alzheimer's disease. As a result, we are evaluating PRX-03140 in a combination trial in concert with donepezil as well as in a monotherapy setting".

PRX-03140 is a novel, oral investigational drug candidate for Alzheimer's disease. It is selective for the 5-HT4 receptor in the brain and is believed to stimulate both acetylcholine production and release, which enables symptomatic improvement in Alzheimer's patients.