Table of contents
- Overview of the trial
- Who the study includes
- Trial phase and study design
- What the researchers measure
- Comparison with the control vaccine
- Key trial details
Overview of the trial
The available trial is a study of YELLOW FEVER VIRUS, STRAIN VYF-247, LIVE in adults with yellow fever, and it is listed as authorised.[1] The study is interventional, which means researchers give a vaccine and then measure what happens.[1]
The trial is being done in Europe and Asia and includes 690 participants.[1] Its main purpose is to compare the immune response after vaccination with the response seen after a control vaccine.[1]
Who the study includes
The study includes adults, and the brief summary says it focuses on participants enrolled in the EU who are YF-naïve.[1] YF-naïve means people who have not previously been exposed to yellow fever in the way described by the study.[1]
This matters because the researchers want to see how well the vaccine response develops in people without prior yellow fever exposure.[1]
Trial phase and study design
This study is in Phase 2.[1] Phase 2 trials usually look more closely at how well a vaccine works and continue to study immune response.[1]
The brief summary says the study is designed to show non-inferiority of the antibody response.[1] In simple words, that means the new vaccine is being tested to see whether its immune response is not worse than the comparison vaccine by more than an allowed amount.[1]
What the researchers measure
The main outcome is the percentage of participants in the EU with seroconversion to yellow fever virus in the YF-naïve population.[1] Seroconversion is defined in the study as a 4-fold increase in neutralizing antibody levels compared with the level before vaccination.[1]
The study measures this result 28 days after vaccine administration.[1] Neutralizing antibodies are part of the body’s immune defense, and the study uses them as a sign that the vaccine has triggered a response.[1]
Comparison with the control vaccine
The investigational vaccine is compared with Stamaril, which is the control vaccine in this study.[1] Both vaccines are given on Day 01 according to the brief summary.[1]
The main question is whether one dose of YELLOW FEVER VIRUS, STRAIN VYF-247, LIVE leads to an antibody response that is not inferior to the response after one dose of Stamaril in YF-naïve participants enrolled in the EU.[1]
Key trial details
Below is a short patient-friendly summary of the trial facts from the source data.[1]
