Assessment of Safety and Immunogenicity of R21/Matrix-M™ in African Children Living With HIV

Inclusion Criteria: * The child must be 5-36 months of age at enrolment (i.e. up to the day of their third birthday). * Group 1: The child must have HIV infection (documented positive DNA PCR) with WHO stage 1 or 2 HIV disease, whether or not they are receiving ART. * Group 2: The child must not have HIV infection (absence of HIV infection must be confirmed by documented negative DNA PCR at screening). * Witnessed, signed/thumb-printed informed consent, obtained from the parent(s)/guardian(s) of the child * Parents/guardians of the child are able and willing to comply with the requirements of the protocol, in the opinion of the investigator * The child must be a permanent resident of the study area and likely to remain resident for the duration of the trial. Exclusion Criteria: * Previous receipt of a malaria vaccine. * Enrolment in another malaria intervention trial that could interfere with the results of this study. * History of severe allergic disease or reactions, including anaphylaxis or angioedema * History of allergic disease or reactions likely to be exacerbated by any component of the study vaccines, or history of allergic reactions to previous vaccinations * Clinically significant laboratory abnormality as judged by the study clinician including haemoglobin of ≤8.0 g/dL . * Major congenital defects. * Receipt of blood transfusion, immunoglobulins and/or any blood products within the three months preceding enrolment * Malnutrition requiring hospital admission at the time of enrolment. * HIV disease of stage 3 or 4, as defined by the WHO clinical staging \[23\] * Confirmed or suspected immunosuppressive or immunodeficient state (other than due to HIV infection). o This may include asplenia, use of immunosuppressant medication within the past 6 months (except for topical steroids or short-term oral steroids (course lasting \<14 days). * Autoimmune conditions (except mild psoriasis, well-controlled autoimmune thyroid disease, vitiligo or stable coeliac disease) * Any other clinically significant disease or disorder, or social situation, elicited in medical history, physical examination or laboratory tests that, in the opinion of the study clinician, may: * Put the participants at risk because of participation in the trial, or * Influence the result of the trial, or * Affect the participant's ability to participate in the trial * These may include: diseases or disorders of the pulmonary, cardiovascular, gastrointestinal, endocrine, neurological, skin, hepatic or renal systems, cancer, bleeding disorders, abnormalities of screening laboratory tests or examinations * Receipt of an investigational drug or vaccine other than the study vaccine within 30 days preceding the first dose of study vaccine, or planned use during the study period. * Current participation in another clinical trial if likely to affect data interpretation of this trial