This clinical trial is focused on studying the effects of a vaccine for COVID-19, a disease caused by the coronavirus. The vaccine being tested is called Comirnaty JN.1, which is a type of mRNA vaccine. This vaccine is designed to help the body recognize and fight the virus that causes COVID-19. The study will involve healthy adults aged 18 to 40 years who have previously received a COVID-19 vaccine at least three months before participating in this trial.
The purpose of the study is to evaluate how the body’s natural defense system, known as the innate immune response, reacts shortly after receiving the Comirnaty JN.1 vaccine. Participants will receive the vaccine through an injection into the muscle. The study will observe the body’s response at different times: before the vaccine is given, and then 6 hours and 24 hours after the injection. Researchers will look at certain markers in the blood that indicate how the immune system is responding.
Throughout the study, researchers will also monitor for any serious side effects that might be related to the vaccine. The study aims to provide more information on how the vaccine affects the immune system in the short term, which can help in understanding its overall effectiveness and safety. The study is expected to conclude by February 2025.



Belgium