Wyeth

In December 2005, Exelixis entered into a license agreement with Wyeth Pharmaceuticals, a division of Wyeth, related to compounds targeting FXR, a nuclear hormone receptor implicated in a variety of metabolic and liver disorders. The license agreement covers several small-molecule compounds that have been shown in preclinical studies to modulate the activity of FXR. Exelixis gained rights to FXR through the acquisition of X-Ceptor Therapeutics, Inc. in October 2004. Exelixis has developed a series of potent, selective synthetic FXR ligands that lower triglycerides and improve the cholesterol profile in animal models of dyslipidemia and atherosclerosis. These compounds are also highly effective in blocking disease progression in animal models of liver disorders.

Under the terms of the agreement, Exelixis received a $10 million upfront payment and will receive up to an additional $147.5 million in development and commercialization milestone payments, as well as royalties on the sale of products commercialized under the collaboration. Wyeth is responsible for all further preclinical and clinical development, regulatory, manufacturing and commercialization activities for the compounds. In November 2006 Exelixis received a $4.5 million payment from Wyeth for achievement of a development milestone, and in 2007 Wyeth paid $2.5 million for achievement of a second development milestone.