Malaria vaccine in clinical trials could reduce deaths by 75 percent

Chia-Yi Hou
·2 min read
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Story at a glance

  • Malaria is caused by parasites from the genus Plasmodium. The single-celled organisms are not viruses or bacteria.

  • There’s currently one vaccine approved by the WHO for use against malaria, but efficacy is low.

  • A new vaccine going through trials had an efficacy rate of 77 percent in a recent trial in Burkina Faso.

Malaria is a mosquito-borne disease caused by a parasite — any of five species from the Plasmodium genus. Symptoms include fever, headaches and chills, and nearly half of the world’s population was at risk of malaria in 2020, according to the World Health Organization (WHO). The only WHO recommended currently available vaccine has a low efficacy rate.

A new vaccine that is nearing the end of phase 3 clinical trials may be the solution we’ve been waiting for, with the potential to prevent up to 77 percent of cases.

The first generation malaria vaccine, named RTS,S/AS01, prevents about 39 percent of malaria cases and about 29 percent of severe cases, according to vaccine studies in children in Africa. In Oct. 2021, it became the first vaccine for malaria to be officially recommended by the WHO. By April 2022, this vaccine has protected more than 1 million children.

It took a long time for RTS,S to get to this point. First developed in 1987, it’s taken three decades to finally be widely administered. Part of the reason why it may have taken so long is that the people affected, “they aren’t Europeans, they’re not Australians, they are poor African children,” said Ashley Birkett, director of the malaria vaccine initiative at PATH, a nonprofit global health organization to Undark. “Unfortunately, I think we have to accept that that is part of the reason for the lack of urgency in the community.”

The new vaccine, named R21, completed phase 2 clinical trials in children 5 to 17 months old in 2019, and potentially has efficacy rates at around 74 to 77 percent, according to a study published in The Lancet. The trial was conducted in Burkina Faso and included 450 children, so it was a small sample size. But, phase 3 clinical trials are ongoing in five countries in Africa, and the researchers running the trials believe approval for the vaccine could happen as soon as 2023.

Adrian Hill, who is director of the Jenner Institute, believes that R21 could reduce deaths by as much as 75 percent by 2030, according to The Guardian. The data are just that good. Thinking about a 2023 approval may seem ambitious, but “then you see [the data],” says Mainga Hamaluba, who is head of clinical research at the Kemri-Wellcome Trust, to The Guardian, “and you think: gosh, this might be possible.”

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