Molecular model of immunoglobulin taking part in immune defence. Credit: Dr_Microbe/ iStock/ Getty Images Plus
A monoclonal antibody has shown promise in second-stage clinical trials, raising hopes that it could be an effective tool in the fight against malaria, one of the biggest killers of children under five in Africa.
The study is the first to show that a monoclonal antibody can prevent malaria in an endemic and real-world setting, says Peter D. Crompton, chief of malaria infection biology and immunology at the US National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, who co-led the study.
The antibody, known as CIS43LS, was up to 88% effective at preventing against infection from Plasmodium falciparum malaria over the course of a six-month intense malaria season. The trial involved 369 healthy adults aged between 18 – 55 years in the rural communities of Kalifabougou and Torodo, in Mali.
Monoclonal antibodies could be considered for clinical use in malaria treatments, according to the Mali Malaria Trial team's findings published in the New England Journal of Medicine.
The team also studied the safety of CIS43LS, administering a single-dose of the intravenous infusion to participants. After 24 weeks, they found the antibody infusion was “very safe and tolerable,” said Kassoum Kayentao, an immunologist at the University of Sciences, Techniques and Technologies (USTTB) in Bamako, who led the trials in Mali.
It could also be used to protect vulnerable groups, including people traveling to malaria endemic regions, especially children under five and pregnant women.
Worldwide, 241 million cases of malaria occurred in 2020 alone, according to the WHO, killing an estimated 627,000 people, mostly in sub-Saharan Africa. The region carries a disproportionately high share of the global malaria burden. About 95% of malaria cases and 96% of malaria deaths in 2020 occurred in sub-Saharan Africa, with children under five accounting for 80% of all malaria deaths in the region.
“It’s a very interesting to see a new potential intervention coming to the fore,” said Jaishree Raman, principal medical scientist at the National Institute for Communicable Diseases in Johannesburg, South Africa.
While monoclonal antibody drugs have been widely used in the treatment of other diseases, including COVID-19, they are costly to manufacture and have to be administered in a hospital. This is not an easy task, particularly in the rural communities most affected by malaria.
Two larger trials to test a second monoclonal antibody, L9LS, in children and adults are currently underway in a few sub-Saharan counties. The hope is that the monoclonal antibodies could one day be used in combination with other tools available, such as antimalarial drugs and insecticide bed-nets.
