Cell Cycle Kinase Inhibitor

In collaboration with Warner-Lambert Company, now Pfizer, we identified a number of lead compounds that modulate the activity of key enzymes that regulate the cell cycle — the process whereby a single cell replicates itself and divides into two identical new cells. Mutations in genes that regulate the cell cycle are present in a majority of human cancers.

Pfizer is developing the most advanced compound in this program — PD 332991, an oral, small molecule cyclin-dependent kinase 4 inhibitor, which entered clinical testing in September 2004. The compound is currently in Phase 2 clinical development.  If Pfizer commercializes this product, Onyx will receive milestone payments and royalties on worldwide sales.