Learn more about RTS,S and the people working toward a vaccine to combat malaria.<br />Photo credit: PATH/Jordan Gantz

RTS,S is the first malaria vaccine recommended for broad use by WHO

In October 2021, the World Health Organization (WHO) recommended RTS,S/AS01 (RTS,S), the world's first malaria vaccine, for use in children at risk in sub-Saharan Africa and in other regions with moderate to high transmission of malaria caused by Plasmodium falciparum. The recommendation was informed by findings from pilot implementation of RTS,S through routine childhood immunization in areas of Ghana, Kenya, and Malawi, as well as other available evidence. The country-led and WHO-coordinated pilots, known as the Malaria Vaccine Implementation Programme, began in 2019. 

The WHO recommendation paved the way for the board of Gavi, the Vaccine Alliance to approve a malaria vaccination program to support the broader rollout of the vaccine in Gavi-eligible countries. 

Data and insights generated from two years of routine vaccination through the pilots showed that delivery of the vaccine is feasible, and high uptake indicated strong community demand. Pilot findings also reaffirmed the vaccine's favorable safety profile, and in areas where it is being deployed, vaccination has substantially reduced the incidence of life-threatening severe malaria. The pilots showed that RTS,S helped to increase equity in access to malaria prevention in vaccinating areas. All three pilot countries had equitable coverage across socio-economic groups, regardless of gender, and more than two-thirds of children in the vaccine implementing areas who were not sleeping under a bednet received the vaccine. This resulted in 90 percent of children benefiting from at least one preventive intervention. 

Findings from other sources also informed the WHO recommendation. Modeling shows that the vaccine has the potential for considerable public health impact, averting one death for every 200 fully vaccinated children. Additionally, drawing on evidence from a recent Phase 3 trial conducted in areas of Burkina Faso and Mali with highly seasonal malaria transmission, the WHO recommendation also notes that countries may consider providing RTS,S in areas with highly seasonal malaria or areas of perennial malaria transmission with seasonal peaks. 

Efforts are now underway to help ensure the long-term, sustainable supply of the RTS,S vaccine, which includes plans for product transfer from the vaccine's developer, GSK, to Bharat Biotech of India. To learn more about the agreement, read the press release. 

RTS,S was created in 1987 by scientists working in GSK laboratories. Early clinical development was conducted in collaboration with the Walter Reed Army Institute of Research. In early 2001, GSK and PATH began a collaboration to develop the vaccine for young children living in malaria-endemic regions in sub-Saharan Africa. The Bill & Melinda Gates Foundation provided catalytic funding to PATH for late-stage development of RTS,S between 2001 and 2015. The vaccine’s efficacy was established in a large Phase 3 trial that concluded in 2014. 

This vaccine aims to trigger the immune system to defend against the first stages of malaria when the Plasmodium falciparum parasite enters the human host’s bloodstream through a mosquito bite and infects liver cells. The vaccine is designed to prevent the parasite from infecting the liver, where it can mature, multiply, reenter the bloodstream, and infect red blood cells, which can lead to disease symptoms. To learn more about RTS,S, read the fact sheet.