Safety and immunogenicity of the malaria candidate vaccines FP9 CS and MVA CS in adult Gambian men.
Imoukhuede EB., Berthoud T., Milligan P., Bojang K., Ismaili J., Keating S., Nwakanma D., Keita S., Njie F., Sowe M., Todryk S., Laidlaw SM., Skinner MA., Lang T., Gilbert S., Greenwood BM., Hill AVS.
We assessed the safety and immunogenicity of prime-boost vectors encoding the Plasmodium falciparum circumsporozoite (CS) protein expressed either in the attenuated fowl-pox virus (FP9) or modified vaccinia virus Ankara (MVA). Thirty-two adult Gambians in groups of four to eight received one, two or three doses of FP9 CS and/or MVA CS. No serious adverse event was observed following vaccination. The most immunogenic regimen was two doses of FP9 followed by a single dose of MVA 4 weeks later (an average of 1000 IFN-gamma spot forming units/million PBMCs). This level of effector T-cell responses appears higher than that seen in previously reported studies of CS-based candidate malaria vaccines.