A Phase IIb trial of a candidate malaria vaccine, R21/Matrix-M has demonstrated high-level efficacy of 77% over 12-months of follow-up.
The vaccine, from the team at the University of Oxford, was trialled in 450 children, aged 5-17 months who were recruited from the catchment area of Nanoro, covering 24 villages and an approximate population of 65,000 people. The randomised, controlled, double-blind trial was conducted at the Clinical Research Unit of Nanoro (CRUN)/Institut de Recherche en Sciences de la Santé (IRSS), Burkina Faso. The vaccine showed a favourable safety profile and was well-tolerated and it also has excellent potential for large-scale manufacturing and low-cost supply.
In their findings published in preprints with the Lancet, the team note that they are the first to meet the World Health Organization’s (WHO’s) Malaria Vaccine Technology Roadmap goal of a vaccine with at least 75% efficacy.
The participants were split into three groups, with the first two groups receiving the R21/Matrix-M (with either a low dose or high dose of the Matrix-M adjuvant) and the third, a rabies vaccine as the control group. Doses were administered from early May 2019 to early August 2019, largely prior to the peak malaria season.
The researchers report a vaccine efficacy of 77% in the higher-dose adjuvant group, and 71% in the lower dose adjuvant group, over 12 months of follow-up, with no serious adverse events related to the vaccine noted.
Following these results, the Phase IIb trial, which was funded by the EDCTP2 programme supported by the European Union (grant number RIA2016V-1649-MMVC), was extended with a booster vaccination administered prior to the next malaria season one year later.