Investigation of Clinical Trial (CT) distribution worldwide associated with the Hepatitis B Virus, Human Immunodeficiency Virus, Malaria and SARS-Cov2 infections.

<strong>Search strategy and selection criteria</strong> We searched the International CT Registry Platform (ICTRP) from the WHO, and ‘ClinicalTrials.gov’ registries for CTs reported in English, without limitation by start year. Primarily for 'HBV', but also ‘HIV’, ‘malaria’ or ‘SARS-CoV-2’ to act as comparators. CT were only eligible for inclusion when focused on the pathogen of interest, but we included studies both of individuals with the relevant infection and of healthy volunteers (e.g., for HBV studies, we permitted ‘CHB’, ‘HBV’, ‘Hepatitis B’ and ’healthy’, with the latter reflecting enrolment for phase I CT for evaluation of HBV-specific interventions). Studies categorized as ‘observational’ (i.e., no intervention) or with missing location data were excluded. CTs were then sorted by WHO region, based on their registered location(s), using R (Version 4.2.1, script here https://doi.org/10.6084/m9.figshare.23667531.v2)