Researchers believe they have developed the world’s most effective malaria vaccine, providing 77-per-cent effectiveness in a randomized trial against the devastating disease that kills more than 400,000 people annually.
In results published on Friday, the researchers from the University of Oxford and its partners said the vaccine is the first malaria shot to exceed the World Health Organization’s target of 75-per-cent effectiveness.
“These are very exciting results showing unprecedented efficacy levels from a vaccine that has been well-tolerated in our trial program,” said Halidou Tinto, a Burkina Faso scientist and the principal investigator in the trial, in a statement on Friday.
Some of the Oxford scientists who led the malaria vaccine research were also involved in developing the Oxford-AstraZeneca vaccine for COVID-19.
The trial of the malaria vaccine was conducted among 450 children up to the age of 17 months, from 24 villages in the West African country of Burkina Faso.
For those who received the vaccine – along with a high dose of an adjuvant to boost immune response – the vaccine had an efficacy rate of 77 per cent with no serious side-effects after 12 months, according to the preprint study in The Lancet, a British medical journal.
While the researchers are planning a larger trial (known as a Phase 3 trial) with about 4,800 children from four African countries, they have already begun working on arrangements for producing millions of doses of the vaccine at the Serum Institute of India, one of the world’s biggest vaccine manufacturers, as soon as regulators have approved it.
The Serum Institute, in a statement on Friday, said it is “highly confident” that it will be able to deliver more than 200 million doses of the malaria vaccine annually.
The new vaccine is cheap to produce, can be manufactured at a large scale and can be stored in ordinary fridges, giving it great potential across the lower-income countries where malaria is widespread, the scientists say.
The trial was conducted in villages in Burkina Faso where children often suffer several cases of malaria in the space of a year. Organizers managed to keep the trial going despite the severe challenges of the COVID-19 pandemic.
For more than a century, scientists have been toiling to find an effective vaccine against malaria, one of the leading causes of childhood death in Africa. More than 270,000 children – mainly in Africa and India – die of malaria every year, and progress in reducing mortality has stalled in recent years.
In some parts of Africa, malaria is responsible for 60 per cent of all visits by children to health clinics. Worldwide, about 229 million cases of the disease were reported in 2019.
Burkina Faso’s Health Minister, Charlemagne Ouédraogo, said the data from the latest trial suggest the vaccine – known as R21/Matrix-M – could be licensed in the coming years. “That would be an extremely important new tool for controlling malaria and saving many lives,” he said in a statement.
An earlier malaria vaccine, known as Mosquirix, took more than 30 years to develop and has shown about 39-per-cent effectiveness in preventing malaria cases so far.
More than 1.7 million doses of the Mosquirix vaccine have been administered in more than 650,000 children over the past two years in Ghana, Kenya and Malawi under a program led by the WHO. A meeting of global advisory boards in October will review the data and decide whether to recommend wider use of the vaccine.
“Ghana, Kenya and Malawi show that existing childhood-vaccination platforms can effectively deliver the malaria vaccine to children,” said a statement by Kate O’Brien, the WHO director of immunization and vaccines.
Health workers have made huge achievements in reducing malaria deaths over the past two decades, largely with protective measures such as distributing insecticide-treated bed nets to protect people from the mosquitos that transmit the disease through parasites in their bites.
But studies have found this improvement in death rates has slowed in recent years, and vaccines are seen as crucial for reviving the progress.
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Geoffrey York