We report the first synthetic peptide vaccine eliciting strong CD8 + and CD4 + T lymphocyte responses in humans.The vaccine, representing the C-terminal region of the circumsporozoite protein of Plasmodium falciparum (amino acids 282-383) was well tolerated and strong sporozoite-specific antibodies were elicited.In addition, robust lymphocyte proliferation responses were equally elicited with concomitant in vitro production of IFN-+ , crucial in the elimination of the parasite.Most importantly, we also observed the development of CD8 + T lymphocyte responses decisive in the immunity to malaria.The latter finding opens new, possibly safer, avenues for vaccination strategies when a CD8 + T cell response is needed.