Malaria Vaccine Effective in Latest Trials

Dec. 9 -- MONDAY, Dec. 8 (HealthDay News) -- Results from two phase II trials in Africa show that a new malaria vaccine is effective at preventing both infection and the mosquito-borne disease itself in infants and children.

"Malaria is killing almost 1 million people, mostly African children, every year," Dr. Christian Loucq, director of the PATH Malaria Vaccine Initiative, said during a morning teleconference Monday. "Clearly, the world needs a safe and effective malaria vaccine."

The vaccine, called RTS,S, is one of several vaccine candidates for malaria, Loucq said. Other vaccines are under development, but RTS,S is the one that is furthest along and ready for phase III testing, he noted.

"These studies offer further evidence that RTS,S provides both infants and young children with substantial protection against the disease," Loucq said. "We are closer than ever before to having a malaria vaccine for use by the children in Africa."

The findings were published online Dec. 8 in the New England Journal of Medicine.

RTS,S was developed by drugmaker Glaxo-Smith-Kline. When the shot is given it also has another component, called either ASO1 or ASO2, which is given to boost the vaccine's effectiveness.

In one study, 340 Tanzanian infants under 1 year old received the RTS,S/ASO2 vaccine along with other vaccines for diphtheria, tetanus, pertussis and heamophilus influenzae B.

"There was a 65 percent reduction in first infection from malaria in those infants who received three doses of the vaccine and were followed over a six-month period," said lead researcher Dr. Salim Abdulla, head of the Bagamoyo Research and Training Centre of the Ifakara Health Institute, in Tanzania. "A safe and efficacious malaria vaccine for children in Africa may be available in the near future and have the potential of alleviating a huge burden of malaria disease," he added.

The researchers also found that RTS,S/ASO2 could be safely and effectively given along with other childhood vaccines. The malaria vaccine did not interfere with the protective responses of other vaccines. And the effectiveness of the RTS,S malaria vaccine wasn't compromised by the other vaccines, Abdulla said.