Long-term immunogenicity and immune memory response to the hepatitis B antigen in the RTS,S/AS01 malaria vaccine in African children: a randomized trial.

RTS,S/AS01 malaria vaccine contains the hepatitis B virus surface antigen and may thus serve as a potential hepatitis B vaccine. To evaluate the impact of RTS,S/AS01 when implemented in the Expanded Program of Immunization, infants 8-12 weeks old were randomized to receive either RTS,S/AS01 or a licensed hepatitis B control vaccine (HepB), both co-administered with various combinations of the following childhood vaccines: diphtheria-tetanus-acellular pertussis- type b, trivalent oral poliovirus, pneumococcal non-typeable protein D conjugate and human rotavirus vaccine. Long-term persistence of antibodies against the circumsporozoite (CS) protein and hepatitis B surface antigen (HBsAg) were assessed, together with the immune memory response to the HB antigen following a booster dose of HepB vaccine.