By Mary Welch

Exelixis Pharmaceutical Inc. expanded its research collaboration with Pharmacia & Upjohn to include the use of technology developed for Exelixis' Mechanism of Action (MOA) program in addition to its PathFinder technology.

"We can't discuss any economic terms," said George Scangos, president and CEO of South San Francisco-based Exelixis. "I can't even say whether we added additional financial parts to this venture, other than to say the entire partnership with Pharmacia involves substantial committed funding, including equity payments over five years."

The MOA program is focused on the identification of molecular targets of existing compounds in order to direct medicinal chemistry efforts to develop better lead compounds.

"Companies like Pharmacia have these compounds but their targets aren't known," he said. "We have developed a set of technology to take these compounds and rapidly find targets. We then give the targets back to Pharmacia and they screen them. They have validated targets, which reduces their risk for drug development. Our MOA program allows us to leverage our ability to use target-based model genetic systems to rapidly identify pharmaceutical targets."

Earlier this year, privately held Exelixis signed a deal with Pharmacia & Upjohn, of Bridgewater, N.J., to identify targets for small-molecule therapeutics in the areas of Alzheimer's disease and metabolic syndrome, including diabetes and obesity. Pharmacia pledged substantial committed funding in the form of research support, an up-front payment and equity with milestone payments, as well as royalties based on future sales of any products. (See BioWorld Today, March 3, 1999, p. 1.)

Exelixis' PathFinder technology works out the biochemical networks involved in disease processes and identifies key points of intervention. Researchers can identify optimal screening targets based on systematic functional genetic assays in whole organisms. Using human disease-associated genes as starting points, PathFinder disrupts the normal functions of the homologous genes in model organisms, then uses systematic mutagenesis to identify other genes that function in the same pathways.