A malaria vaccine, being tested in Burkina Faso, has shown very promising results, showing that it is 80 percent effective in preventing the disease in children, after a booster dose one year after the first administration. The result significantly exceeds the 75 percent efficacy threshold set by the World Health Organization (WHO) to define a vaccine against malaria as useful.
The results of the clinical trial were published in the medical journal Lancet Infectious Diseases this week. The study explains how the immune response can be restored to levels comparable to the first administration, even after the booster dose. The vaccine is called R21 and was developed by the University of Oxford (UK) in collaboration with other health institutions and the US biotechnology company Novavax.
The clinical trial involved 450 children aged 17 months to 5 years in Burkina Faso, where malaria occurs mostly seasonally. For this, further trials will be necessary, because the administration of the vaccine just before the start of the malaria season can affect the results, simply because the vaccinated are more protected against the disease when it occurs. In places where malaria is more or less constant during the year, it can be infected many months after vaccination.
However, clinical trials with the R21 vaccine are underway in four other African countries, with a project involving around 4,800 children. The results of these trials may offer new data on the efficacy of the vaccine and the booster dose. The first data should be available by the autumn and will also be analyzed by WHO experts.
The new vaccine could be quickly made available to many countries, thanks to an agreement with the Serum Institute, the world‘s leading vaccine manufacturer based in India, which has committed to producing up to 200 million doses per year. , as soon as there are authorizations from the health authorities. The volume of vaccines produced would be much larger than the few tens of millions expected for the RTS, S vaccine, approved by the WHO last year and made by the pharmaceutical company GlaxoSmithKline.
The World Health Organization (WHO) estimates that more than 200 million people come into contact with malaria every year, almost always from mosquitoes that are healthy carriers of the disease. If treated immediately, a patient can recover without particular problems, avoiding complications, but in many rural areas of Africa, Asia and Latin America it is often impossible to receive adequate health care. It is estimated that around 430,000 people worldwide died of malaria in 2015 alone. For this reason, research efforts are directed towards systems to reduce the number of infections, for example by developing a truly effective vaccine or reducing the risk of getting sick from mosquitoes.