Phase 1b Study to Evaluate Safety and Immune Response of Multi-Stage Malaria Vaccines R21, RH5.1, and R78C with Matrix-M in Adults and Young Children in Burkina Faso

What this Trial Is About

Researchers are evaluating the safety and immune response of a multi-stage malaria vaccine candidate combining R21 with RH5.1 andor R78C in Matrix-M adjuvant. This Phase Ib open-label study includes healthy adults aged 18 to 35 years and children aged 5 to 17 months in Burkina Faso. The study aims to test different combinations of these vaccines to better understand their effects in populations living in malaria-endemic areas. Participants are divided into six groups. Adults receive three doses of 5 g R21 plus 10 g RH5.1 and 10 g R78C. Children receive different combinations of 5 g or 10 g doses of R21, RH5.1, and R78C vaccines. Each participant receives three intramuscular injections at months 0, 1, and 6, either in the deltoid muscle for adults or the anterolateral thigh for children. Safety monitoring includes staggered recruitment, sentinel participants, and Data Safety Monitoring Board reviews before age de-escalation and subsequent vaccinations. Participants will undergo safety assessments for solicited and unsolicited adverse events at multiple time points up to one year following the first vaccination. Blood samples for immunology testing will be collected at screening, vaccination days, and several follow-ups up to day 365. The study includes ongoing monitoring of serious adverse events and immune responses to evaluate how well the vaccine combinations are tolerated and stimulate the immune system over time.

A Study to Assess the Experimental Malaria Vaccines R78C and RH5.1 Combined With R21/Matrix-M (a "Multi-stage" Malaria Vaccine)