A New Malaria Vaccine Has Promising Efficacy Rates

Malaria is a deadly disease transmitted through parasites found in mosquitoes. It is most common in Asia and Africa, but threatens much of South America as well. In 2019 alone, there were around 229 million cases worldwide. However, Oxford University recently released a report on their breakthrough with a highly effective and safe malaria vaccine. 

The Study:

Researchers at Oxford University conducted a double-blind, randomised trial of a R21/MM vaccine. Children between the ages of five and seventeen from Nanoro, Africa, were recruited. Nanoro has high malaria transmission, especially during the June to November rainy season. They gave three vaccines at 4-week intervals and a fourth booster dose after a year. 450 children participated in the study, and they were divided into 3 groups. Group 1 received 5μg R21/25μg MM, Group 2 received 5μg  R21/50μg MM, and Group 3, the control group, received a rabies vaccine. As this was a double-blind study, nobody but the pharmacists knew which shot each person was getting. The team recorded the safety, efficacy, and immunogenicity of the vaccine over the course of two years. After each vaccine was administered, the participants recorded any adverse reactions for seven days. After the seven days, only severe adverse reactions were noted.   

The Results:

In Group 1, 43 out of the 146 participants got malaria within the first 6 months after the third vaccine. In Group 2, 38 out of 146 participants got the virus while in Group 3, 105 out of the 147 participants got it. This makes the vaccine efficacy 74% from Group 1 to the control group and 77% from Group 2 to the control group. 12 months after the third vaccine, Group 1 had 50 cases of malaria, group two had 39, and group 3 had 106. Fever was the most common side effect, but the vaccine otherwise showed high safety and efficacy. There were only seven severe adverse effects, but none of them were caused by the vaccine and they all had to do with unrelated medical conditions. 

Annika Shekdar ‘24

Ledford, Heidi. “Malaria Vaccine Shows Promise — Now Come Tougher Trials.” Nature, vol. 593, no. 7857, Apr. 2021, pp. 17–17, doi:10.1038/d41586-021-01096-7.