Results published in The Lancet Infectious Diseases in September 2022 demonstrated “high efficacy” for a booster vaccine against malaria. The vaccine, described as having “world-changing potential”, is expected to be rolled out in 2023. R21/Matrix-M was studied in Burkina Faso, an area of “highly seasonal malaria transmission”.
The trial
The trial was a double-blind Phase II/IIIb randomised controlled trial. It was done in children between 5 and 17 months old in Nanoro, Burkina Faso. The vaccination programme involved three vaccinations followed by a booster 12 months later. The publication states that “vaccine safety, efficacy, and a potential correlate of efficacy with immunogenicity, measured as anti-NANP antibody titres, were evaluated over 1 year following the first booster”.
“Vaccine efficacy remained high in the high adjuvant dose group, similar to previous findings at 1 year after the primary series of vaccinations.”
The study reveals that in the low-dose adjuvant group efficacy was 71% and in the high-dose adjuvant group it was 80%. This meets the WHO-specified efficacy goal of 75% or greater. Professor Adrian Hill of the Jenner Institute at the University of Oxford suggests that these are the “best data yet”.
Halidou Tinto, Professor in Parasitology and Regional Director of IRSS in Nanoro, was the Principal Investigator of the trial. He is excited by the results: “it is fantastic to see such high efficacy again after a single booster dose”.
The trial will continue for 2 more years to assess the value of further booster doses and longer-term safety.
Putting results into practice
The charity Malaria No More is pleased with recent progress, as it means that preventing child deaths from malaria might be possible “in our lifetimes”. As well as positive results, the practicalities of producing the vaccine might be good news. The BBC reports that the vaccine is “cheap”, and a deal is in place to manufacture over 100 million doses a year.
The team will begin seeking approval for the vaccine throughout September, with a final decision based on the results of a larger trial of 4,800 children. This is expected by 2023.
The Serum Institute of India, the “world’s largest vaccine manufacturer”, is on stand-by to produce the doses. Professor Hill suggests that it can be made for “a few dollars”.
“We really could be looking at a very substantial reduction in that horrendous burden of malaria.”
However, the BBC reports that the currently approved vaccine, produced by GlaxoSmithKline, which has “partly paved the way for Oxford”, has undergone “large real-world trials”. By contrast, Oxford’s data “may appear more effective” due to the timing of peak season in Burkina Faso. Furthermore, concerns about investment have been raised. Professor Azra Ghani of Imperial College London warned that although the results are “welcome”, the need for investment was pressing.
“We risk losing the gains that have been made over the last decades”
A test for Truss
Gareth Jenkins, Director of Advocacy at Malaria No More UK remarked that the data from this trial are “encouraging”.
“With the right support, the world could end child deaths from malaria in our lifetimes”.
However, he emphasised the need for British leadership, identifying the “imminent US-hosted Global Fund to Fight AIDS, Tuberculosis, and Malaria replenishment conference”. This takes place in September 2022.
“This will be the new PM’s first foreign policy test – for the sake of millions of children’s lives, global health security, and British relations with its closest ally, it’s a test they cannot fail.”
We look forward to hearing more on malaria vaccine progress from Professor Katie Ewer of the Jenner Institute at the World Vaccine Congress in Europe, 2022. To join us get your tickets here.
