3 Oct 2023 • The World Health Organization (WHO) has recommended a new vaccine, R21/Matrix-M, for the prevention of malaria in children. The recommendation was endorsed by the WHO Director-General following its regular biannual meeting held on 25-29 September.

The R21 vaccine is the second malaria vaccine recommended by WHO, following the RTS,S/AS01 vaccine, which received a WHO recommendation in 2021.The addition of R21 to the list of WHO-recommended malaria vaccines is expected to result in sufficient vaccine supply to benefit all children living in areas where malaria is a public health risk.

Key features of the R21 malaria vaccine: The updated WHO malaria vaccine recommendation is informed by evidence from an ongoing R21 vaccine clinical trial and other studies, which showed:

• High efficacy when given just before the high transmission season: In areas with highly seasonal malaria transmission (where malaria transmission is largely limited to 4 or 5 months per year), the R21 vaccine was shown to reduce symptomatic cases of malaria by 75% during the 12 months following a 3-dose series. A fourth dose given a year after the third maintained efficacy. This high efficacy is similar to the efficacy demonstrated when RTS,S is given seasonally. 
• Good efficacy when given in an age-based schedule: The vaccine showed good efficacy (66%) during the 12 months following the first 3 doses. A fourth dose a year after the third maintained efficacy.
• High impact: Mathematical modelling estimates indicate the public health impact of the R21 vaccine is expected to be high in a wide range of malaria transmission settings, including low transmission settings.
• Cost effectiveness: The cost-effectiveness of the R21 vaccine would be comparable with other recommended malaria interventions and other childhood vaccines.
• Similarity of R21 and RTS,S vaccines: The two WHO-recommended vaccines, R21 and RTS,S, have not been tested in a head-to-head trial. There is no evidence to date showing one vaccine performs better than the other. The choice of product to be used in a country should be based on programmatic characteristics, vaccine supply, and vaccine affordability
• Safety: The R21 vaccine was shown to be safe in clinical trials. As with other new vaccines, safety monitoring will continue.

WHO also issued recommendations on the advice of SAGE for new vaccines for dengue and meningitis, along with immunization schedule and product recommendations for COVID-19. Click here to read the full story!