SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Exelixis, Inc. (Nasdaq:EXEL) today announced that it has notified GlaxoSmithKline (GSK) that it has achieved proof-of-concept for XL184 under the collaboration agreement between GSK and Exelixis, and has submitted the corresponding data report to GSK. Under the agreement, GSK has 90 days to review the data and decide whether to exercise its option to select the compound for further development and commercialization. If GSK selects XL184, Exelixis would receive a $55 million milestone creditable by GSK against outstanding amounts under the loan facility between the parties, and potentially would receive commercialization milestones, royalties on product sales, and certain co-promotion rights in North America. Exelixis anticipates a decision from GSK by late October 2008.
