According to WHO, Malaria kills 409 000 people in 2019 alone worldwide. Among these deaths, 94% are in Africa. In the same year, they invested US$ 3 billion in research and in malarial control and elimination. Currently, RTS, S/AS01 is the most effective malarial vaccine. However, its efficacy is only 55.8% over 12 months in African children.
New Vaccine, R21/MM malaria vaccine
A new study posted in Preprints with The Lancet has brought optimism among researchers working in Malaria. According to the study conducted by scientists from the University of Oxford in collaboration with Novavax and Serum Institute of India, the vaccine they developed called R21/MM vaccine showed 74-77% efficacy after 1 year in children from Africa. This finding is definitely positive progress towards achieving the WHO’s goal of reducing malaria cases by 90% by 2030.
The researchers conducted a double-blind, randomized, controlled trial in 450 children aged 5-17 months in Nanoro, Burkina Faso, a highly endemic region. They divided the children into three groups. They gave children in one group rabies vaccine as a CONTROL group. They gave the children in other two groups a low-dose circumsporozoite protein-based vaccine along with two different doses of adjuvant, Matrix-M. All the vaccines (CONTROL and experiment) were given in three doses at 4-week intervals prior to the malaria season. A booster dose was given a year later.
The researcher studied the efficacy, safety, and immunogenicity over a year. After 6 months, they found that the efficacy to be 74% and 77% in low doses adjuvant and high doses group, respectively. After a year, the efficacy remains 77% in the high dose adjuvant group. Among the children in the control group, 105 (71.4%) developed Malaria. However, only 29.5% and 26% of children in the experimental group develop malaria.
What is R21/MM vaccine made of?
They made the vaccine in yeast, comprise hepatitis B surface protein combined with a piece of a protein that coats the surface of the malaria parasite when it first invades its human host.
Comments from scientists
Pedro Alonso, director of the World Health Organization (WHO) Global Malaria Programme calls it ‘very positive news’ but he also stressed the importance of conducting trial in bigger numbers. Remember, they conducted this trial on 450 children only.
‘The R21 results are encouraging’, says Kwadwo Koram, an epidemiologist at the University of Ghana in Accra.
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Advantages of R21/MM vaccine
This new R21/MM malaria vaccine candidate has its advantages that it has a potential for large-scale manufacturing and low-cost supply, to support global efforts to better control, sustainably eliminate, and finally eradicate malaria.
Takeaway from the research.
Even though the efficacy is only 75%, if it is coupled with other preventive measures, such as effective mosquito control, it could help to reduce deaths and help in achieving the WHO goal of reducing cases by 90% by 2030.
High Efficacy of a Low Dose Candidate Malaria Vaccine, R21 in 1 Adjuvant Matrix-M™, with Seasonal Administration to Children in Burkina Faso, 2020 Lancet preprint