ChAd63 RH5

ChAd63 RH5 is an investigational malaria vaccine candidate designed to prevent blood-stage infection by Plasmodium falciparum. It uses a replication-deficient simian adenovirus vector (ChAd63) engineered to express the reticulocyte-binding protein homologue 5 (RH5), a critical antigen required for parasite invasion of human red blood cells. The vaccine aims to induce both cellular and humoral immune responses, including the production of antibodies that neutralize P. falciparum by blocking the interaction between RH5 and its erythrocyte receptor, basigin. ChAd63 RH5 is typically used as a priming immunization in heterologous prime-boost regimens with MVA RH5 (a modified vaccinia Ankara vector expressing the same antigen). Clinical trials have demonstrated that ChAd63 RH5 is safe and immunogenic in adults, children, and infants, eliciting strong T cell responses and functional antibodies capable of inhibiting parasite growth in vitro[1][6][7][9]. The vaccine has been developed primarily at the University of Oxford with manufacturing support from Advent.