THE world’s first vaccine for malaria has won the backing of European regulators, a critical step toward widespread immunisation against a disease that takes half a million lives every year in Africa.
The Mosquirix vaccine from GlaxoSmithKline has been under development for 28 years. While deaths have been slashed by 58% since 2000 through treatment and prevention measures such as mosquito eradication, a definitive fix has eluded researchers.
The vaccine won the scientific approval of the European Medicines Agency (EMA), Glaxo said Friday. Under World Health Organisation rules, the EMA’s thumbs-up was needed before WHO would consider supporting its use, which in turn helps gain approvals by African nations where malaria claims most of its victims, usually children.
In 2013, there were an estimated 584,000 deaths from malaria with around 90% of these occurring in sub-Saharan Africa, and 83% in children under the age of five in the region, according to GSK data.
Even though the vaccine is still not very effective, only reducing malaria cases by about a third, experts agree that’s far better than nothing, because children often get malaria more than once.
More than 16,000 children were treated in the final Glaxo study in seven African countries. The vaccine—also known as RTS,S—was first given to infants between 6 and 12 weeks old, and children between 5 and 17 months old.
The regimen of three doses plus a later booster shot reduced the number of malaria cases by 39% in the older group, and by 27% in the infants, according to Glaxo.
Because children can get malaria more than once, the vaccine prevented 6,000 cases per 1,000 vaccinated children over four years in areas with the highest rate of the disease. The booster was necessary because the effects waned over time.
“This is a major scientific breakthrough,” said Moncef Slaoui, who heads the company’s vaccines division and has worked on the drug since 1987. The reason it took so long “was not because we were lazy, but because we had to invent it,” Slaoui said.
Glaxo struggled to develop the shot because it’s the first vaccine to target a parasite, rather than a bacterium or virus. The company spent more than $365 million on the drug, which was also funded with grants from the Bill & Melinda Gates Foundation.
Glaxo said it intends to set the price of the drug to cover the cost of manufacturing, plus a markup of about 5% to be reinvested in additional research. The drugmaker is reportedly looking at pricing the shot at $5 – the same as an insecticide-treated bed net.
Evade immune response
Even though the parasite causing malaria, Plasmodium, was first identified in 1880, and the role of mosquitoes in its spread was discovered in 1898, developing a vaccine has been very difficult because Plasmodium has a complex life cycle, and has evolved to specifically evade the immune response once in the body.
A WHO spokesman said the Geneva-based organisation’s decision on whether to back the vaccine will be based on factors the EMA doesn’t take into account, such as cost-effectiveness and how it compares to other malaria-fighting measures.
“Any financing for this vaccine must not draw resources away from scaling up bed nets, effective drugs and rapid diagnostic tests for malaria,” WHO spokesman Gregory Hartl said in an e-mailed statement. The WHO decision is due in November, Hartl said.
After the decision, GSK will then apply to the WHO for a scientific review of the vaccine, which will be used by the UN and other agencies to help make purchasing decisions.
The trials were conducted with prevention efforts such as bed nets in place, which helped reduce the overall number of cases, according to Slaoui. In a more-typical environment, where people have less protection, the benefits of vaccination could be greater.
“Our expectation is real-life effectiveness is substantially higher than in the trial,” Slaoui, whose name is on the patent, said in a phone interview.
The product is made from a combination of genes from the proteins found in the malaria parasite and the hepatitis B virus, and blocks the parasite from multiplying in the liver.