Safety, Immunogenicity of RTS,S/AS02A, and RTS,S/AS01B Malaria Vaccines in Malaria-experienced Adults.

Overview

The candidate malaria vaccine RTS,S/AS02A developed by GSK Biologicals demonstrated 30% efficacy against clinical episodes of malaria and approximately 58% efficacy against severe malaria disease. As a potential improvement to RTS,S/AS02A, another candidate vaccine RTS,S/AS01B is being developed in parallel in collaboration with the Walter Reed Army Institute of Research (WRAIR). This study will be the first administration of the RTS,S/AS01B vaccine to the African adults to establish safety and immunogenicity in this population. Preliminary indication of vaccine efficacy with this adjuvant will be established by monitoring the time to the first infection with Plasmodium falciparum.

The study comprises of 3 groups and the participating subjects will be randomly allocated to one of the three groups. The first group will receive RTS,S/AS01B, the second group will receive RTS,S/AS02A and the third group will receive rabies vaccine. Immunization will be given by IM injection on 0, 1, 2 month schedule. Infants will be followed up daily for 7 days for solicited symptoms and 30 days for unsolicited symptoms after each vaccine dose. Serious adverse events will be recorded throughout the study period. A week prior to Dose 3, subjects will be treated with a licenced anti-malarial drug. Starting from two weeks after Dose 3, the subjects will be monitored for a 14-week duration for detection of malaria infection.

Conditions