A Phase 1 Study to Assess an Escalating Dose, Multi-prime Vaccination Schedule of R21/Matrix-M™

Inclusion Criteria: * Healthy adult aged 18 to 50 years. * Able and willing (in the Investigator's opinion) to comply with all study requirements. * Participants of childbearing potential only: must practice continuous effective contraception until the last study visit. * Agreement to refrain from blood donation for the duration of the study. * Able and willing to provide written informed consent to participate in the trial. Exclusion Criteria: * History of clinical malaria (any species) or previous participation in any malaria vaccine trial or controlled human malaria infection trial. * Travel to a clearly malaria endemic locality during the study period or within the preceding six months, as per the CDC website: https://www.cdc.gov/malaria/travelers/country\_table/a.html * Participation in another research study involving receipt of an investigational medicinal product (IMP) in the 30 days preceding enrolment or 5 half-lives of the investigational medicinal product, whichever is longer, or planned participation during the study period. * Prior receipt of an IMP likely to impact interpretation of the trial data, as assessed by the Investigator. * Receipt of any vaccine within 30 days of a study vaccine, with the exception of COVID-19 vaccination. * Receipt of oral or systemic immunosuppressant medication for more than 14 days in the six months preceding enrolment. * Receipt of immunoglobulins or blood products (e.g. blood transfusion) in the three months preceding enrolme…