Having trained as a Consultant in Infectious Diseases and completed a DPhil in Oxford developing a human challenge model against tuberculosis, using BCG, my main research interest is in human challenge models of infection. My work as Chief Investigator on the blood-stage and transmission-blocking malaria vaccine programmes at the University of Oxford involves testing first-time-in-human vaccines against Plasmodium falciparum, incorporating controlled human malaria infection to test vaccine efficacy, both in the UK and Tanzania. I have also established a human challenge model for Plasmodium vivax malaria and am leading on UK efficacy trials of the two front-running blood-stage vaccine candidates for P. vivax malaria. During the pandemic I was involved in initial development, implementation and medical oversight of the Phase I-III ChAdOx1-nCOV-19 vaccine trials. I have since led as site Principal Investigator on multiple COVID-19 vaccine trials (Phase II-III), in adults and adolescents, at the Oxford Vaccine Group and Oxford Health NHS Trust.