GlaxoSmithKline and Cellzome Announce Major Strategic Alliance

Kinobeads™ technology to identify a new generation of drug candidates for inflammatory diseases London, United Kingdom, Philadelphia, Penn., Cambridge, United Kingdom and Heidelberg, Germany, 10th September 2008 - Cellzome Inc. and GlaxoSmithKline (LSE & NYSE: GSK) announce the signing of a worldwide strategic alliance to discover, develop and market novel kinase-targeted therapeutics to treat inflammatory diseases.

The alliance gives GSK access to Cellzome’s significant expertise in identifying and developing selective kinase inhibitors and its proprietary Kinobeads™ technology which, by screening compounds in a physiological setting, is designed to improve the predictability of these drug candidates’ performance in clinical testing. Kinases are key molecular switches in cellular signaling events with a central role in many inflammatory responses and selective inhibitors offer a different approach to therapeutic intervention in diseases such as rheumatoid arthritis or multiple sclerosis.

Under the agreement GSK has exclusive options to license drug candidates from Cellzome’s kinase programs directed against four identified targets, and three additional targets to be jointly identified by both parties. In the alliance, Cellzome will utilize its proprietary Kinobeads™ technology to discover novel small molecule inhibitors of these targets, and then will develop the most promising product candidates through to completion of a clinical proof of concept trial, unless GSK elects to exercise its option earlier. Cellzome is eligible to receive success-based milestones from GSK as product candidates are advanced. Upon Cellzome’s achievement of clinical proof of concept for a product candidate for a particular kinase target, GSK would have an exclusive option to license all product candidates from that program. GSK would then assume full responsibility for further clinical development and commercialization on a worldwide basis. Cellzome retains the right to continue the development and commercialization of drug candidates if GSK chooses not to exercise its option to that program.

Under the terms of the agreement, Cellzome will receive upfront payments of £14.4 million comprised of both cash and equity. Cellzome is eligible for up to £118 million per program in potential development, regulatory and commercial milestones and up to double digit royalties on net sales of products resulting from the alliance.

Jose Carlos Gutierrez-Ramos, Ph.D, Senior Vice President and Head of the Immuno-Inflammation Centre of Excellence for Drug Discovery of GSK said: “GSK is committed to becoming a world leader in immuno-inflammation drug discovery by finding transformative medicines through internal efforts and external collaborations. We are excited to be working with Cellzome to discover and develop improved approaches to existing biologic therapies which cannot access intracellular signaling mechanisms. Cellzome’s Kinobeads™ technology will provide a distinct advantage because it uses native kinases directly isolated from human cells and tissues.”

Tim Edwards, CEO of Cellzome, said: “We are very pleased to begin a strategic alliance with GSK, one of the world’s leading pharmaceutical R&D companies. This alliance is a significant endorsement of our leading Kinobeads™ technology, programs and people. It is a major event in Cellzome’s development, giving us the opportunity to broaden our pipeline and progress several kinase programs towards the clinic, ultimately for the benefit of patients.”