Study of AS01 Adjuvant to Boost Immune Response and Protection in Adults Aged 21 to 59

What this Trial Is About

As people age, their immune system weakens, making them more vulnerable to infections and less responsive to vaccines. This trial studies a vaccine ingredient called AS01, which is used in vaccines like shingles. Researchers want to see if AS01 alone can strengthen and train the immune system, helping it fight various infections better, and how long these effects last in adults aged 21 to 59. Participants will receive a single dose of AS01 or a placebo injection. Afterward, they will be randomly assigned to get a yellow fever vaccine either one month or three months later. The study compares immune responses and viral control after these treatments over two to four months, depending on the group. During the study, participants will have blood samples taken at several timepoints to measure immune changes and responses to the yellow fever vaccine. Researchers will analyze gene expression, immune cell activity, and viral levels to understand the effects of AS01. Safety will be monitored throughout, with participants tracked for up to four months after treatment.

Improving Vaccine Protection for Adults