Malaria vaccine trial raises hope

The war on malaria has been taken a notch higher.

First results from a large-scale trial of a new vaccine, RTS,S, published online in the New England Journal of Medicine, show it can give children significant protection against the deadly disease that is responsible for close to 800,000 deaths each year.

RTS,S is the scientific name of this malaria vaccine candidate. It aims to trigger the immune system to defend itself against the plasmodium falciparum malaria parasite when it first enters the human host’s bloodstream and/or when the parasite infects liver cells.

The vaccine is designed to prevent the parasite from infecting, maturing and multiplying in the liver, and from re-entering the bloodstream and infecting red blood cells.

“A vaccine is the simplest, most cost-effective way to save lives. These results demonstrate the power of working with partners to create a malaria vaccine that has the potential to protect millions of children from this devastating disease,” said Bill Gates, co-chair of the Bill & Melinda Gates Foundation.

The trial is one of the final stages in evaluating the efficacy and safety of the vaccine in infants and young children before regulatory file submission.

The results were announced on Tuesday at the Malaria Forum hosted by the Bill & Melinda Gates Foundation in Seattle, Washington State.

The trials, in seven countries across sub-Saharan Africa, showed that three doses of RTS,S reduced the risk of children experiencing clinical malaria and severe malaria by 56 per cent and 47 per cent, respectively.

This analysis was performed on data from the first 6,000 children aged 5 to 17 months over a 12-month period.

The widespread coverage of insecticide-treated bed nets (75 per cent in this study indicated that RTS,S can provide protection in addition to that already offered by existing malaria control interventions.

If the required public health information, including safety and efficacy data from the Phase III programme is deemed satisfactory, WHO has indicated that a policy recommendation for the RTS,S malaria vaccine candidate is possible as early as 2015.

“The publication of the first results in children aged 5 to 17 months marks an important milestone in the development of RTS,S. These results confirm findings from previous Phase II studies and support ongoing efforts to advance the development of this malaria vaccine candidate,” said Tsiri Agbenyega, a principal investigator of the trial and chair of the clinical trials partnership committee.