But a new vaccine, developed by Oxford scientists, may prove far more effective in fighting malaria. Called R21, the jab was shown to be 80% effective in protecting against the disease in a trial reported in the Lancet on September 7, 2022. “Based on these results, this vaccine could have a significant impact on eliminating malaria from affected areas of the world,” said Neil Mabbott, professor of immunopathology at the University of Edinburgh, who was not involved in the research. “This is a truly remarkable achievement.” Scientists who led the trial say the jabs could start being produced and distributed as early as next year. The vaccine is said to be cheap to make, and the Serum Institute of India, a vaccine manufacturer, has committed to producing 100 million doses a year. Malaria kills about 600,000 people a year, most of whom are babies and children. About 95% of the 200 million cases diagnosed annually are found on the African continent. Creating a vaccine for malaria is difficult It is not easy to make a vaccine for the disease, which is spread by mosquitoes, because the parasite that causes it evolves as it infects the body to evade the immune system. “The malaria parasite is constantly changing,” Mabbott said. “This makes it difficult for our immune system to detect and destroy it, and even more difficult to vaccinate against it.” The R21 vaccine targets the first stage of the parasite’s life cycle inside the body, preventing it from spreading and infecting the liver. The R21 vaccine trial In the trial, researchers found that a booster dose one year after the initial vaccination was on average 75% effective in protecting against the virus. Participants, all infants between 5 and 17 months of age, were recruited from a province in central Burkina Faso. They were divided into three groups: Two received the vaccine in different doses and a third, control group received anti-rabies vaccine. In all, about 400 infants got the jab. One group received a higher dose of the vaccine and was about 80% protected from the virus, while the other group received a lower dose and saw around 70% protection. What’s next for the R21 vaccine? The trial has been extended for two years to determine whether a four-dose vaccine regimen is sufficient or whether more booster doses will be needed. Initial data from that trial appeared to suggest “that booster doses are likely to be needed to maintain protection,” Brian Greenwood, professor of tropical medicine at the London School of Hygiene & Tropical Medicine, said in a media briefing. Greenwood was not involved in the R21 investigation. And the results of a much larger study – involving 4,800 babies in four African countries – will also be published later in 2022. The large sample will be able to provide a more specific picture of the vaccine’s effectiveness. Editor: Zulfikar Abbany
