EXELIXIS ANNOUNCES ANTICANCER COMPOUNDS TRIAL

Exelixis has announced plans for Phase II programs for its three most advanced internally generated development compounds, XL999, XL647 and XL784.

XL999 and XL647 are anticancer compounds, currently in late Phase I trials and the company intends to begin a Phase II program for each of these compounds before the end of the year. XL784 has completed a single dose Phase I trial as well as additional toxicology and formulation development in preparation for a Phase II program to test its utility in diabetic nephropathy.

Based on the specific targets of each compound, preclinical data, and insights gained during the Phase I trials, the company intends to carry out expanded Phase II programs for each of the compounds. XL999 and XL647 each will be tested in multiple tumor types, and XL784 will be moved forward in diabetic nephropathy. All of these trials will be funded through the financing that the company obtained from Symphony Capital during the second quarter of 2005. The company expects that Phase II data for XL999 and XL647 will be available in 2006, and that the Phase II trial for XL784 in diabetic nephropathy will take fifteen to eighteen months to complete.