ChAd63 CS

ChAd63 CS is an investigational malaria vaccine candidate that uses a replication-deficient chimpanzee adenovirus serotype 63 (ChAd63) viral vector to deliver the gene encoding the circumsporozoite protein (CS) of *Plasmodium falciparum*. The vaccine is designed to induce strong cellular and humoral immune responses against the malaria parasite, particularly targeting its pre-erythrocytic stages. ChAd63 CS has been evaluated both as a single agent and in heterologous prime-boost regimens with MVA CS (modified vaccinia virus Ankara expressing the same antigen). Clinical studies have shown that ChAd63 CS is safe and highly immunogenic, inducing high levels of antigen-specific CD4+ and CD8+ T cell responses as well as modest but persistent antibody responses. Its primary indication is for the prevention of malaria caused by *P. falciparum*, with clinical trials demonstrating reduction in liver-stage parasite burden following controlled human malaria infection[1][2][3][4][5].