GSK buys Corixa for $300 million

recently announced the execution of a definitive agreement to acquire

, a Seattle-based developer of products that regulate immunity.

The acquisition is structured as a cash for stock transaction, with the shareholders of Corixa entitled to receive $4.40 per common share, representing a total value of approximately $300 million.

As a result of the acquisition, GSK will acquire all scientific and business programs, activities, assets and all related rights of Corixa. GSK will also acquire Corixa’s manufacturing facility in Hamilton, Montana, which produces Monophosphoryl Lipid A (MPL), an adjuvant contained in many of the vaccines in GSK’s pipeline.

Furthermore, GSK will no longer incur royalties and other costs under the existing agreements in place between GSK and Corixa nor will GSK incur royalties on future sales of their vaccines containing MPL.

GSK will also acquire all assets related to a candidate prophylactic tuberculosis vaccine and to a portfolio of candidate immunotherapeutic cancer vaccines, being developed by GSK Biologicals and which contain antigens discovered by Corixa pursuant to a 1998 multi-field vaccine discovery collaboration between the companies. As a result of the acquisition, GSK will no longer be required to pay royalties related to these antigens. Corixa’s portfolio also includes other compounds such as TLR4 agonists and antagonists.