THRIVE - Trial of Passive Humoral RSV Immunity for Value and Effectiveness

RSV is a leading cause of severe respiratory illness and hospitalisation for young children, with particularly high rates of RSV respiratory infection observed amongst Aboriginal and Torres Strait Islander children living in Australia's Northern Territory. The goal of this clinical trial is to evaluate whether routinely administering a single dose of respiratory syncytial virus (RSV)-specific monoclonal antibody, nirsevimab, from 6 months old, provides protection against RSV infections for Aboriginal and Torres Strait Islander children throughout in the first and second year of life. In this study, participants will be randomly assigned to receive either a single dose of intra-muscular RSV-specific monoclonal antibody, nirsevimab, or standard care (no RSV-specific monoclonal antibody). The primary objective is to determine whether administration ofRSV-specific monoclonal antibody, nirsevimab reduces the occurrence of RSV infection over the subsequent 12 months. Secondary objectives include assessing whether nirsevimab reduces RSV-related hospital attendances, as well as respiratory and all-cause hospitalisations, over the following 6 and 12 months. An assessment of cost-effectiveness will also be undertaken. Participants will receive the study intervention at 6 months of age (+90 days). Follow-up will be conducted through passive surveillance using electronic medical records and public health notification systems to capture relevant health outcomes.