Malaria vaccine shows high efficacy
doi:10.1038/nindia.2021.60 Published online 28 April 2021
A malaria vaccine, administered to African children living in a malaria-endemic region, has proven to be up to 77 per cent effective1.
The research, published preprint (yet to be peer reviewed) meets the 75 per cent efficacy goal set by the World Health Organization.
A one-year follow-up study has shown that the vaccine is well-tolerated with mild or no adverse side effects among the children, according to an international research team. The researchers say that it is possible to mass-produce the vaccine at an affordable cost to better control, and eventually eradicate, malaria.
Among the malaria parasites, Plasmodium falciparum that triggers malignant malaria has developed resistance to several drugs. There is no effective vaccine against this deadly parasite.
The scientists, including a researcher from the Pune-based Serum Institute of India Private Limited, produced the vaccine by fusing a P. falciparum protein with a specific hepatitis B virus protein and expressing the recombinant as virus-like particles in yeast.
The vaccine, loaded with an immune-boosting saponin-based ingredient, was then administered to children between 5 and 17 months living in a malaria-prone region of Burkina Faso in West Africa.
Four weeks past the third vaccination, the children showed high levels of malaria-specific antibodies in their blood. Increasing the dose of the saponin-based agent almost doubled the levels of the antibodies.
The antibody levels waned slowly but were boosted after a fourth dose administered one year later. In contrast to another malaria vaccine administered in the same region, the new vaccine showed a higher efficacy level at a lower dose.
1. Datoo, S. M. et al. High efficacy of a low dose candidate malaria vaccine, R21 in adjuvant Matrix-M™, with seasonal administration to children in Burkina Faso. Lancet. (2021) Doi:10.2139/ssrn.3830681