world's first malaria vaccine, representing a major step toward prevention of a disease that kills more than half a million people worldwide every year - most of whom are children in Africa.
After assessing the quality, safety and efficacy of the vaccine -called RTS,S (brand name Mosquirix) - the European
Medicines Agency's (EMA) Committee for Medicinal Products
for Human Use (CHMP) conclude it should be used for immunization of children in Africa aged 6 weeks to 17 months, alongside other protective measures against malaria - such as
insecticides and bed nets.
The CHMP recommendation is the first step toward RTS'S becoming the first licensed vaccine for malaria.
Later this year, independent advisory groups from the World Health Organization (WHO) will review evidence for the vaccine and decide whether to recommend its use.
Malaria is a life-threatening disease caused by Plasmodium
parasites, transmitted to humans through the bite of Anopheles
mosquitoes.
The most deadly malaria parasite is Plasmodium falciparum, which the RTS,S vaccine targets. The vaccine works by inducing an immune response in the body when P. falciparum first enters the bloodstream, preventing the parasite from infecting and multiplying in the liver.
There were an estimated 198 million cases of malaria around
the globe in 2013 and around 584,000 deaths from the disease.
Around 90% of these deaths occurred in Africa, mostly among
children under the age of 5 years.
At present, the only effective preventive measures against
malaria in Africa are the use of artemisinin-based combination
therapies (ACTs) - which need to be administered within 24 hours of fever onset - and insecticides and bed nets to prevent mosquito bites.
If licensed, however, the RTS,S vaccine - manufactured by British pharmaceutical company GlaxoSmithKline (GSK) - would be used alongside existing malaria-prevention strategies; in clinical trials, the vaccine has not proved effective enough to
be used alone.
RTS'S would provide 'meaningful contribution' to controlling malaria burden
Earlier this year, Medical News Today reported on the results of a phase 3 clinical trial for RTS,S, which were published in
The Lancet.
The trial involved 15,459 infants and 6-12 weeks and children aged 5-17 months from 11 sites across seven sub-Saharan countries, including Ghana, Kenya, Malawi and Mozambique.
Initial trial results revealed that among participants aged 5-17 months who received three doses of RTS,S, a 46% drop in
malaria cases was observed in the 18 months following, while
infants aged 6-12 weeks saw a 27% reduction in malaria cases.
The researchers then followed participants for a further 20-30
months after administering a booster vaccine 18 months after
the third dose.
The 3-dose RTS,S regime plus the booster vaccine was found to reduce the number of malaria cases by 39% among children aged 5-17 months over a total of 4 years follow-up, while a 27% fall in malaria cases was found over 3 years of follow-up among infants aged 6-12 weeks.
Importantly, the trial results show that without a booster
vaccine, the effect of RTS,S wanes over time. In addition, the absence of a booster jab impairs the vaccine's ability to
reduce cases of severe malaria.
Because RTS,S does not offer complete protection against
malaria, the CHMP say "It is important that established
protective measures, for example, insecticide-treated bed nets, continue to be used in addition to the vaccine."
Still, it is estimated that in areas of sub-Saharan Africa with the highest malaria burden, RTS,S could prevent more than 6,000 malaria cases for every 1,000 children vaccinated.
Earlier this week, MNT reported on a study published in Science Translational Medicine, in which researchers reveal the discovery of a compound that could prevent and treat malaria by stopping P. falciparum from becoming drug
resistant.
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