EXELIXIS STARTS THREE NEW TRIALS FOR ANTICANCER COMPOUNDS

Exelixis has initiated Phase I clinical trials to evaluate the safety, tolerability and pharmacokinetic profile of two anticancer compounds, XL844 and XL184. The Phase I trial for XL844 will be conducted in patients with chronic lymphocytic leukemia, and the Phase I trial for XL184 will be conducted in patients with solid tumors for whom there are no available therapies. In addition, a repeat-dose Phase I clinical trial for XL784 has been initiated in healthy volunteers, in preparation for a Phase II program to test efficacy in patients with renal failure.

XL844 is an orally available, potent inhibitor of Chk 1 and 2, two protein kinases that facilitate DNA repair after exposure to DNA-damaging agents (e.g., chemotherapy). Chk inhibition blocks the ability of cells to detect and repair DNA damage, and in tumor models leads to increased efficiency of chemotherapeutic agents and radiation. XL844 is believed to be the most advanced small molecule inhibitor of Chk 1 and 2 in clinical studies.

XL184 is a novel, orally administered, small molecule anticancer compound that in preclinical models has demonstrated potent inhibition of both the hepatocyte growth factor receptor and the vascular endothelial growth factor receptor 2.