Published 26.04.2021 by Schmitt Trading Ltd.
After 12 months of conducting research on 450 Burkinabé children, researchers from the University of Oxford’s Jenner Institute recently discovered that an experimental vaccine produced to tackle the most life-threatening form of malaria parasite had between 74% and 77% efficacy against malaria in the children. This milestone comes after decades of obtaining unsatisfactory results, and the discovery has resurrected hopes that an effective vaccine can be produced to tackle malaria which kills an estimated 400,000 people per annum, mostly children.
Halidou Tinto, who is a principal investigator at the study location and parasitologist at the Institute for Health Sciences Research (Nanoro, Burkina Faso), stated that the discovery is astonishing because the efficacy achieved in the research on 450 children has never been achieved by any malaria vaccine candidate. Three doses of vaccine were given at 4 weeks intervals to the children aged between 5 months and 17 months, and a booster dose was given to them at 12 months.
The booster dosage restored the children even though their respective antibodies to malaria declined over 12 months. Among 146 children who were administered a sample of the vaccine containing a high dose of an immune-boosting compound, 38 of them developed malaria; among 147 children who were administered with rabies vaccine, 105 of them also developed malaria. The efficacy which was initially 77% efficacy against malaria, dropped to 74% in children who were administered the vaccine that had a lesser dose of the immune-boosting compound.
On hearing about the results of the research, the World Health Organization (WHO) Director of Global Malaria Programme, Pedro Alonso, responded by saying it is “very positive news.” However, he noted stated that the research was conducted on 450 children, and the results are still far off from the type of results that would make them get too excited. In a plan to conduct research on a larger study group, researchers intend to enroll 4,800 children in Burkina Faso, Kenya, Mali, and Tanzania and involve them in a phase 3 trial study which is expected to start later this year.
The study’s chief investigator, Adrian Hill stated that all things being equal, results from the planned research could be presented to regulators in the late part of 2022 to seek approval of same in early 2023, and hopefully, if the results facilitate approval, emergency use authorizations (EUAs) for malaria vaccines will be issued as was the case for COVID-19 vaccines.
The research used the malaria vaccine which is produced in yeast, and consists of hepatitis B surface protein joined together with a piece of protein that overlays the surface of malaria parasites when they initially enter a human body. The group of Oxford researchers has collaborated with Serum Institute of India which is producing vaccines for the planned phase 3 trial and has promised to make 200 million doses in the years ahead. Chief investigator, Adrian Hill, stated that the cost per dose of vaccine will be lesser than it has ever been before.
Prior to the success of this recent malaria vaccine study, the highest level of efficacy ever achieved for a vaccine against malaria was 56% after 12 months. This efficacy was for Mosquirix produced by GlaxoSmithKline; unfortunately, after 4 years of being developed, its efficacy against malaria reduced to 36%. Vaccine developers have been facing challenges to achieve higher efficacy because of malaria parasites’ complicated life cycle and changing surface proteins; on the other hand, the World Health Organization has urged vaccine developers to develop vaccines that would hopefully reduce malaria cases by 75% by the year 2030.
Despite the results achieved by the Oxford group of researchers, some people have been concerned and skeptical about what they refer to as “deficiencies” in regard to some of the data used in research; as a result, they have advised that researchers should tread with caution because there is no certainty that the vaccine will compete effectively against all parasites. Rhoel Dinglasan, who studies malaria at the University of Florida’s Emerging Pathogens Institute, noted that the efficacy of the GlaxoSmithKline malaria vaccine, which was much higher when it was initially produced, had reduced to 33.4%.