The Ebola vaccine furthest along in development has cleared a critical milestone and edged closer to entering large-scale efficacy trials in West African countries hard hit by the current epidemic.
As reported online today in The New England Journal of Medicine (NEJM), a U.S. study done in 20 healthy people at no risk of developing the disease found the vaccine caused no serious side effects and, as hoped, triggered immune responses against the Ebola virus. The vaccine, jointly developed by GlaxoSmithKline (GSK) and the U.S. National Institute of Allergy and Infectious Diseases (NIAID), contains a gene for the Ebola surface protein stitched inside a harmless chimpanzee adenovirus. Researchers at NIAID in Bethesda, Maryland, began the trial on 2 September, and the super–fast-track development of the vaccine could move it into trials involving 15,000 people in Liberia and Sierra Leone at high risk of developing the disease as soon as mid-January, NIAID Director Anthony Fauci told ScienceInsider.
Other small studies of the vaccine, which, combined, involve 260 people, are under way in Mali, the United Kingdom, and Switzerland and should produce data by the end of next month. Ripley Ballou, who heads Ebola vaccine development for GSK, told ScienceInsider that the company needs these data before it can finalize plans for efficacy studies. In particular, Ballou says the ongoing trials should clarify which dose of the vaccine will trigger the most robust immune responses without side effects.