Despite several control initiatives, malaria remains a persistent public health problem, particularly in Sub-Saharan Africa where most clinical cases and deaths occur. Recently, two pre-erythrocytic vaccines, RTS,S and R21, have been recommended by WHO for use in children living in malaria endemic areas. However, a promising malaria blood-stage vaccine is not yet in the pipeline.
February 2024
A recent trial in malaria-exposed, healthy Burkinabe adults and children living in malaria hyperendemic and seasonal area, was the first trial where the blood-stage malaria vaccine BK-SE36/CpG was administered to different age groups. The vaccine was found to be safe and induced anti-SE36 antibodies in all cohorts. In 5- to 10-year-old children, the risk of malaria infection was markedly lower in the BK-SE36/CpG arm compared to the control arm (See: doi:10.3389/fimmu.2023.1267372[1]
As information on the persistence of antibody levels after vaccination is important for further vaccine development, a follow-up study entitled "Persistence of Anti-SE36 Antibodies Induced by the Malaria Vaccine Candidate BK-SE36/CpG in 5–10-Year-Old Burkinabe Children Naturally Exposed to Malaria" was conducted three years after the first vaccination. Results showed that a high percentage of vaccinated children still had detectable antibodies against SE-36 compared to the control group. Antibody levels tended to decline over time but remained higher in the vaccinated group. Factors like pre-existing antibodies and participants' sex didn't significantly affect the immune response to the vaccine. This data demonstrates the long-term persistence of the antibody titres induced by the BK-SE36/CpG vaccine candidate and supports further research to investigate its efficacy in larger clinical trials, determine the level of antibodies needed for protection and assess the role of natural infection in boosting the vaccine-induced humoral immune response.
Read the full manuscript:
Issa Nebie 1,†, Nirianne Marie Q. Palacpac 2,† , Edith Christiane Bougouma 1 , Amidou Diarra 1, Alphonse Ouédraogo 1 , Flavia D’Alessio 3 , Sophie Houard 3 , Alfred B. Tiono 1 , Simon Cousens 4 , Toshihiro Horii 2,* and Sodiomon B. Sirima 1,* ➡️ DOI: https://doi.org/10.3390/vaccines12020166
See more about SEMALVAC2 project: https://www.euvaccine.eu/malaria-vaccines/SEmalvac2
[1] Ouédraogo, A. et al. (2023) ‘Safety and immunogenicity of BK-SE36/CPG malaria vaccine in healthy burkinabe adults and children: A phase 1b randomised, controlled, double-blinded, age de-escalation trial’, Frontiers in Immunology, 14. doi:10.3389/fimmu.2023.1267372).
This project has received funding from Global Health Innovative Technology Fund (GHIT) and Nobelpharma.
Photo credit: Photo by Roman Nguyen on Unsplash