Results published online in the New England Journal of Medicine revealed that the world''s most clinically advanced malaria vaccine candidate provides both infants and young children with significant protection against malaria. Two separate phase II trials reaffirmed earlier study results and support the ongoing efforts, pending regulatory approvals, to launch the phase III study of GlaxoSmithKline Biologicals'' RTS,S/AS vaccine candidate across Africa. In infants, data show for the first time that the vaccine candidate can be administered as part of existing African national immunization programs. In children aged 5 to 17 months, the candidate RTS,S/AS01 reduced the risk of clinical episodes of malaria by 53 percent over an eight-month follow-up period and was shown to have a promising safety profile. The studies were conducted in Kenya and Tanzania. RTS,S/AS is the leading candidate in a global effort coordinated by the PATH Malaria Vaccine Initiative (MVI) to develop a malaria vaccine. Malaria kills almost one million people each year -- most of them infants and young children in Africa, the intended recipients for this vaccine candidate. GSK and the PATH Malaria Vaccine Initiative signed a public-private partnership agreement in 2001 to pursue pediatric clinical development of RTS,S/AS in Africa. To advance the development program, African research centers in five countries, and collaborating institutions, joined with the partnership. Pending approvals by national regulatory agencies and ethics committees, a multi-center phase III efficacy trial is on track to start in early 2009. The trial will seek to confirm and evaluate with precision the vaccine''s efficacy, including duration, and will continue to closely monitor safety. The vaccine was invented, developed and manufactured in laboratories at GSK Biologicals'' headquarters in Belgium in the late 1980s and initially tested in US volunteers through a partnership with the US Walter Reed Army Institute of Research. Funding for the development of this vaccine candidate has been made possible through a US$107.6 million grant from the Bill & Melinda Gates Foundation to the PATH Malaria Vaccine Initiative. GSK has invested approximately $300 million to date and expects to invest another $50-100 million before the completion of the project. The clinical development of RTS,S/AS is led by the Clinical Trial Partnership Committee, a collaboration of leading African research institutes, Northern academic partners, MVI and GSK with support from the Malaria Clinical Trial Alliance.