Malaria Vaccine Trial

Efficacy of GSK Biologicals’ candidate malaria vaccine (257049)(RTS,S/AS01) against malaria disease caused by P. falciparum in infants and children in Africa.

PI: RTS,S Clinical trials partnership (there are no PIs)(LSHTM investigators include Chandramohan Drakeley,  Greenwood, Riley and Schellenberg)

This phase three trial is being conducted in 11 centres in 7 countries in sub-Saharan Africa and involves 16,000 infants or young children. Analysis of data obtained 12 or 18 months after vaccination has shown that the vaccine provides about 50% protection against uncomplicated and severe malaria when given in three doses at one monthly intervals to children aged 5-17 months outside the routine immunisation programme. However, when given to infants aged 6-12 weeks at the same time as routine EPI vaccines, protective efficacy is less and wanes rapidly.  Why this should be the case is being investigated. Half of the children in the RTS,S group have received a booster dose of vaccine at the age of 18 months to determine whether this can restore waning immunity. A further and final formal analysis of this very large database will take place in mid 2014 when the majority of subjects will have been followed for 3-4 years. It is expected that a decision on registration of the vaccine will be made in 2015 and, if this is successful, WHO will issue policy guidelines on its use shortly afterwards.