Huge analysis of RTS,S in Africa shows it decreased toddler deaths by 13%

In a major analysis in Africa, the first vaccine approved to fight malaria cut deaths among young children by 13% over nearly 4 years, the World Health Organization (WHO) reported last week. The huge evaluation of a pilot rollout of the vaccine, called RTS,S or Mosquirix and made by GlaxoSmithKline, also showed a 22% reduction in severe malaria in kids young enough to receive a three-shot series. Hundreds of thousands of children are born annually in the parts of Ghana, Kenya, and Malawi included in the analysis, for which WHO revealed the final data on 20 October at the annual meeting of the American Society of Tropical Medicine and Hygiene.

“The RTS,S malaria vaccine is already saving lives,” said John Tanko Bawa, director of malaria vaccine implementation at PATH, a nonprofit that develops vaccines and therapies for global health problems. He added, “What we have seen is a considerable impact of a vaccine described as having modest efficacy.” (A late-stage clinical trial delivered lackluster results on the durability of the vaccine’s protection.)

The 13% drop in deaths is so remarkable that “I was surprised I didn’t hear any gasps when it was stated,” joked medical epidemiologist Mary Hamel, who led the WHO pilot program. The mortality decline could translate to tens of thousands of lives saved if RTS,S, which WHO approved for widespread use in 2021, is more broadly deployed: In 2021, malaria killed an estimated 468,000 children under age 5 in sub-Saharan Africa. Seventeen countries in the region have already won approval to receive doses that will start to roll out next year.

“The data speak for themselves,” said Kwaku Poku Asante, a physician and epidemiologist who directs the Kintampo Health Research Centre and who oversaw the analysis in Ghana. “This was a very large, very robust evaluation done in a real-life setting, and you’re seeing this huge impact.”

In clinical trial results published in 2015, RTS,S showed 36.3% efficacy against clinical malaria a median of 4 years after toddlers were vaccinated. In the $70 million pilot, mandated by WHO and launched in 2019, nearly 2 million very young children have been vaccinated in the three countries...