LONDON—In early May, GSK announced the execution of a definitive agreement to purchase Seattle, Wash.-based Corixa Corp., a developer of immunotherapeutic agents and adjuvants. The move represents a strategic deal for the pharmaceutical firm's vaccine division, GSK Biologicals, as it further enhances the division's position in the global vaccine market, which is expected to reach beyond $10 billion by 2010.
Under the terms of the agreement, GSK will acquire all of the scientific and business programs, activities, and related rights of Corixa. It also acquires Corixa's manufacturing facilities in Hamilton, Mont., which produce the novel chemical adjuvant MPL that is used in many GSK vaccines. In exchange, GSK offered Corixa shareholders $4.40 per share, a 48 percent premium over the previous day's closing price. The deal, which is expected to close in the third quarter of 2005, will cost GSK $300 million.
"GSK already has long-term supply contracts for MPL in place, as well as a strategy to increase its manufacturing capacity," says Anne Walsh, vice president for worldwide communications at GSK Biologicals. "However, the acquisition of Corixa provides GSK with increased control over the production of this key vaccine component. On the basis of forecasts for future vaccine production (Fendrix, Malaria, Cervarix, etc) and filing timing accelerations (Cervarix Cervical Cancer Vaccine), GSK Bio has an increasing demand for MPL."
"Corixa and GSK have been partners on multiple projects for many years," explains Dr. Steven Gillis, Corixa co-founder, chairman and CEO. "Our partnership has spanned discovery and development of vaccine antigens, licensing of Corixa's adjuvants for incorporation in GSK vaccines, and shared development and marketing of [cancer therapetic agent] Bexxar. The agreement to be acquired by GSK represents further integration of our efforts and is a logical step given the importance of Corixa's flagship adjuvant MPL in multiple GSK vaccines."
MPL has proven critical to GSK's vaccine program, explains Ms. Walsh, as it has been demonstrated in a number of the company's vaccine candidates to enhance the immune response, both in terms of antibodies and cell-mediated immunity, as to allow for a protection against the disease that is not observed with the antigen alone.
In the deal, GSK also acquires assets related to a candidate tuberculosis vaccine and potential cancer immunotherapeutics developed by GSK Biologicals on the basis of antigens identified by Corixa during an earlier vaccine discovery collaboration.
"GSK has many collaborations with outside biotech companies on both antigens and adjuvants and in-licenses many different types of technology on a regular basis to optimize the development of its ever-growing vaccine pipeline," adds Ms. Walsh. "Corixa does not have a vaccine pipeline, but rather an adjuvant portfolio and some antigens developed in collaboration with GSK under agreement."
The deal has unanimous approval of Corixa's Board of Directors, but is still subject to approval of its shareholders, regulators, and certain other conditions. It is not expected that the agreement will interfere with existing MPL supply or collaboration agreements that Corixa has with other companies such as Biomira, Wyeth, and Allergy Therapeutics, nor should it impose a burden or represent a business hurdle to GSK, says Ms. Walsh.