Comparing Two Ways to Give the R21Matrix-M Malaria Vaccine to Young Children in Chad One Way Follows Routine Vaccination, the Other Matches Seasonal Malaria Prevention Campaigns

What this Trial Is About

Researchers are evaluating two different ways of giving the R21Matrix-M malaria vaccine to children in Chad who live in areas with high seasonal malaria. This phase IV trial compares the usual method of giving the vaccine as part of routine immunizations to a new method that aligns vaccine doses with seasonal malaria prevention campaigns. The study aims to understand how well the vaccine protects against malaria and how practical and cost-effective the new synchronized approach is in real-life conditions. The trial involves 26 clusters, each defined by the area served by a primary care health center. Clusters are randomly assigned to either receive the vaccine doses throughout the year as part of the routine Expanded Programme on Immunisation EPI or to receive the vaccine doses synchronized with the seasonal malaria chemoprevention SMC campaign. Both groups receive three primary doses of the vaccine followed by a booster dose, with timing varying between the two groups. Alongside the main trial, qualitative interviews and an economic evaluation will assess acceptability, feasibility, costs, and cost-effectiveness of the vaccination strategies. Children participating in the study will be monitored for malaria cases through enhanced surveillance at health centers and hospitals over 17 months from August 2025 to December 2026. Surveys will measure vaccine coverage and use of other malaria prevention methods. A nested case-control study will look specifically at protection against severe malaria. Researchers will also evaluate safety, side effects, and the overall impact of these vaccination strategies. Participation involves health visits, interviews, and data collection to understand the vaccines real-world use and effects.

Comparison of Two Strategies for Administering the R21-Matrix M Vaccine in a Context of Seasonal Malaria Transmission in Chad