Malaria vaccine modestly beneficial in infants

The most recent trial of the first malaria vaccine in the world demonstrated modest benefits in African infants, showing less promise than an earlier study that halved cases in older babies.

The research team determined that the vaccine reduced clinical malaria risk by 31 percent and severe malaria risk by 26 percent in babies between six to 12 weeks of age after receiving the first vaccine dose. The Phase III trial enrolled 15,000 children at 11 centers in seven African countries, CIDRAP News reports.

The scientists gave the RTS,S malaria candidate vaccine to 6,537 of the children. Researchers compared the results with a control group that received a meningococcal vaccine. The groups received the vaccine with their standard childhood vaccines.

An earlier phase of the trial at the same clinics determined that the vaccine had 56 percent efficacy against clinical malaria and 47 percent efficacy against severe disease when given to children between five months and 17 months of age.

"(The lower efficacy rate) makes us even more eager to gather and analyze more data from the trial to determine what factors might influence efficacy against malaria and to better understand the potential of RTS,S in our battle against this devastating disease," Salim Abdulla, a principal investigator from the Ifakara Health Institute in Tanzania, said, according to CIDRAP News. "We were also glad to see that the study indicated that RTS,S could be administered to young infants along with standard childhood vaccines and that side effects were similar to what we would see with those vaccines."

While the trial results suggest that the vaccine may not be ready for routine use in infants, Johanna Daily, a doctor with the Albert Einstein College of Medicine's division of infectious diseases, said the trial could help researchers to find host responses correlating with protection.

"The results of this immunization trial suggest that a malaria vaccine is possible, but a more detailed understanding of effective host responses will be necessary," Daily said, according to CIDRAP News.