Second malaria vaccine has high protection – 02/05/2024 – Health

A malaria vaccine developed by the University of Oxford and the Serum Institute of India prevented about three-quarters of symptomatic cases of malaria in young children in the first year after receiving the doses, the results of a major study published last Thursday showed. -Friday (1st).

The vaccine, which has already been approved for use by regulators in three West African countries and the World Health Organization, is the second available. The first vaccine was launched in Cameroon earlier this year and was developed by pharmaceutical company GSK.

Both vaccines have the potential to make major advances against an ancient mosquito-borne disease that still kills more than half a million people, mostly young children in sub-Saharan Africa, each year. “This is what we’ve been waiting for for decades,” Mary Hamel, WHO’s head of malaria vaccine implementation, said in an interview.

She said having two safe and effective malaria vaccines was important to meet demand. The results of the late-stage trial for the Oxford and Serum vaccine, known as R21, were published in the medical journal The Lancet on Thursday.

In a survey of 4,800 children in four African countries, the vaccine prevented 75% of malaria cases in children aged 5 to 36 months in areas where the initial three doses were administered before the peak malaria season. It prevented 68% of cases in areas where transmission occurs year-round.

The researchers said effectiveness was maintained with a booster a year later, although protection appeared to wane over time. The research is ongoing. “It’s something else we can add,” said Brian Greenwood, a professor at the London School of Hygiene and Tropical Medicine who has worked on vaccines for decades. “Now what is needed is to learn how to best use these vaccines,” he added, referring to the possible need for regular boosters, as well as combining the doses with preventative medicines and tools such as mosquito nets.

He and other experts said comparing the two vaccines directly was difficult because of the many variables involved in the trials, including the age of the children vaccinated and the length of time they were studied, the coverage of preventive medications given along with the doses, and the levels of transmission. of malaria in an area, among other elements.

Despite suggestions that R21 is unique in its protection, when the vaccines are compared under the same conditions, their performance is similar, experts said — a conclusion endorsed by the WHO.

The key difference is that the new R21 vaccine is cheaper, costing about $3 per dose, and more readily available. There are only 18 million doses of GSK’s vaccine available until 2026, but 25 million doses of R21 have already been produced by Serum for this year, CEO Adar Poonawalla told Reuters ahead of the results.

The vaccine also includes an adjuvant, or immune-boosting portion, made by Novavax. “There is no capacity issue, and we will provide further updates in three to four months as more countries express demand,” he said in an emailed statement.

Alassane Dicko, who led the R21 trial in Mali, said vaccines must be rolled out as quickly as possible. “What we need to do now is get vaccines to children,” he said.