Initiative to Develop Second-Generation Malaria Vaccine

The PATH Malaria Vaccine Initiative (MVI) announces that it has entered into a collaboration with Dutch biopharmaceutical company Crucell N.V. and GlaxoSmithKline (GSK). This collaboration is aimed at developing a second-generation vaccine against malaria a deadly disease that kills close to 800,000 people annually, most of them young children under age 5 in Africa. MVI drives the development of malaria vaccines by joining its scientific, managerial, and field expertise with companies, universities, and governments to test potential malaria vaccines and invest in those with the most promise.

The new project will bring together two promising vaccine approaches in an effort to develop a malaria vaccine that may have the potential to improve on the efficacy of GSKs first generation RTS,S vaccine candidate. In this collaborative effort, a single dose of Crucells weakened recombinant adenovirus Ad35.CS.01malaria vaccine approach will be administered, followed by two doses of GSKs RTS,S malaria vaccine candidate in a Phase 1/2a clinical trial that is expected to begin later this year. This would be the first test in humans of this "heterologous prime-boost" approach against malaria.

The RTS,S vaccine candidate is currently in the midst of a large-scale Phase 3 clinical efficacy trial. If all goes well in Phase 3 testing, the World Health Organization (WHO) has indicated that a policy recommendation for RTS,S is possible as early as 2015, paving the way for countries to make a decision about implementation through their national immunization programs. The RTS,S trial, which is the outcome of a decade-long collaboration between MVI and GSK, involves 11 sites in seven African countries.

Crucell and MVI first began working together in 2007 to develop adenovirus-based vaccines targeting malaria and are currently collaborating on another heterologous prime-boost approach. Crucells Ad35.CS.01 was recently tested in a Phase 1 clinical study in the United States.

RTS,S is a circumsporozoite protein (CSP)-based pre-erythrocytic P. falciparum malaria vaccine candidate that incorporates GSKs AS01 adjuvant. Crucells Ad35.CS.01 vaccine approach uses a weakened, recombinant adenovirus (a type of virus associated with the common cold and other mild respiratory infections) to deliver a malaria antigen to the immune system.

In preclinical studies, the regimen to be evaluated under the new MVI-GSK-Crucell collaboration has shown enhanced immunogenicity when compared to either vaccine candidate given alone.