Wyeth Pharmaceuticals, the pharmaceutical division of Wyeth, has entered into an agreement with Solvay Pharmaceuticals to co-develop and co-commercialize four neuroscience compounds, most notably, bifeprunox - a late-stage compound in Phase 3 development for schizophrenia and other possible uses.

Also, under the terms of the agreement, the Solvay Pharmaceuticals mental health sales force will begin promoting Effexor XR (venlafaxine HCl), Wyeth's serotonin-norepinephrine reuptake inhibitor (SNRI), in the United States by midyear. Financial terms of the transaction have not been disclosed.

"This agreement reinforces Wyeth's leadership position in the field of neuroscience. The co-development of four promising compounds fits in well with our current development portfolio, and we are especially excited about bifeprunox and its potential as a novel treatment for schizophrenia," says Bernard Poussot, president, Wyeth Pharmaceuticals. "Through the expansion of sales support for Effexor XR, we will have the opportunity to increase our market share by communicating important information about its use to a larger number of physicians."

Bifeprunox is in Phase 3 development as an atypical antipsychotic for the treatment of schizophrenia and other psychotic disorders. The other compounds, currently known as SLV-310, SLV-313, and SLV-314, are in earlier stages of development and are being studied as treatments for schizophrenia, bipolar disorder, major depressive disorder with psychotic features, and other indications.

Schizophrenia and bipolar disorder each [b1] affect more than 2.6 million people in the United States. In schizophrenia, efficacy remains the unmet need in the treatment of both positive and negative symptoms. Common examples of negative symptoms include social withdrawal and apathy, and positive symptoms include delusions and hallucinations. Further, there is great need for new atypical antipsychotics that have minimal effect on weight and a low risk to induce diabetes and other metabolic complications. It is estimated that the market potential in treating psychosis is approximately $10 billion.