The global fight against malaria has taken a significant leap forward with the development of the first blood-stage malaria vaccine, RH5.1/Matrix-M. According to a report released by GlobalData, a leading data and analytics company, the vaccine has shown promising results and could play a crucial role in the evolving strategy against malaria. The report also reveals that there are currently 11 other malaria vaccines in Phase II development. However, the RH5.1/Matrix-M vaccine stands out due to its safety, effectiveness, and high immunogenicity, as per a recent study conducted by researchers in Burkina Faso and the UK.
The study, a double-blind, randomized, controlled, phase 2b trial, involved 361 children aged between 5 and 17 months. The results showed that the RH5.1/Matrix-M vaccine is 55% effective against clinical malaria when administered in a delayed third-dose regimen at 0, 1, and 5 months. Furthermore, the vaccine demonstrated over 80% efficacy against high levels of malaria parasites, indicating its potential effectiveness in preventing severe disease. The vaccine was found to be generally safe and well-tolerated, with no serious adverse events reported. These findings were published in The Lancet Infectious Diseases.
Stephanie Kurdach, an Infectious Disease Analyst at GlobalData, stated, “RH5.1/Matrix-M has the potential to be the first blood-stage malaria vaccine brought to market. This could be a much-needed addition to the currently available malaria vaccines and provide an important second line of defense for those most at risk of contracting malaria.” Malaria is a mosquito-borne disease caused by parasitic Plasmodium protozoans. It is primarily spread through the bite of an infected female Anopheles mosquito. The symptoms of malaria can vary widely, ranging from fever, chills, and headache to confusion, seizures, and difficulty breathing.
As immunity to the disease wanes over time, sporozoites, the early stage of the parasite, can infect the liver and lead to blood-stage clinical malaria infection. Despite progress in some nations that have been certified as malaria-free, the burden of malaria remains high, particularly within the World Health Organization’s (WHO) African Region. Currently, there are only two malaria vaccines, GSK’s Mosquirix and Serum Institute of India ‘s R21/Matrix-M, that are WHO prequalified and recommended for use in children. These vaccines target the early sporozoite stage of the parasite.
The development of a blood-stage malaria vaccine like RH5.1/Matrix-M could replace these vaccines and provide a second line of defense. Kurdach noted, “There are 11 other malaria vaccines currently in Phase II development, including pre-erythrocytic vaccines and blood-stage vaccines from manufacturers such as BioNTech, GSK, the National Institute of Allergy and Infectious Diseases (NIAID), and Vac4All SAS.” However, she added that no new malaria vaccines are in Phase III development or pre-registration at this time.
The study of the RH5.1/Matrix-M vaccine was conducted by scientists at the University of Oxford in collaboration with several other institutions including the Clinical Research Unit of Nanoro in Burkina Faso, the London School of Hygiene and Tropical Medicine, and the National Institute of Health in the USA. The participants were divided into two groups, with one group receiving three doses of the RH5.1/Matrix-M vaccine and the other receiving three doses of a rabies vaccine as a control. The study was conducted in a manner that neither the participants, their families, nor the study teams knew who received which vaccine.