In short
Clinical trials are studying INFLUENZA VIRUS B/AUSTRIA/1359417/2021 - LIKE STRAIN (B/AUSTRIA/1359417/2021, MEDI 355292) as part of influenza vaccine research. These studies look at immune response, antibody levels, and viral shedding after nasal or intramuscular vaccination in children and healthy people. Most trials are Phase 3 and aim to compare different vaccine routes and measure protection-related markers.
Key points
- Clinical trials investigating INFLUENZA VIRUS B/AUSTRIA/1359417/2021 - LIKE STRAIN (B/AUSTRIA/1359417/2021, MEDI 355292) are studying influenza vaccination in children and healthy individuals. All listed studies are Phase 3 and are authorised. The trials compare nasal live attenuated influenza vaccine with intramuscular inactivated influenza vaccine, and one study also includes a placebo nasal spray. Main outcomes include viral shedding, mucosal antibody levels, and CD4+ T-cell responses. These studies aim to better understand immune response in the nose and airways after vaccination.
Trial overview
These trials study INFLUENZA VIRUS B/AUSTRIA/1359417/2021 - LIKE STRAIN (B/AUSTRIA/1359417/2021, MEDI 355292) in the setting of influenza vaccination research. All three listed studies are Phase 3 and are marked as Authorised. The studies are interventional, which means researchers give a vaccine and then measure the results.
Who is being studied
One study focuses on young children and looks at immune response in the nasopharynx, which is the upper part of the throat behind the nose. Another study includes healthy individuals and compares antibody responses after different vaccine routes. The VAXXAIR trial studies airway immunity after nasal and intramuscular influenza vaccination.
What is being measured
The first trial measures the presence or absence of viral shedding after the first and second dose of live attenuated influenza vaccine in nasal lining fluid. Viral shedding means the vaccine virus can be found in a sample, and this can be used as a marker of how the body responds. The VAXXAIR trial measures CD4+ T-lymphocytes and mucosal antibody rises in respiratory secretions over several time points after vaccination. The third trial measures the fold change in influenza-specific IgA in nasal fluid at day 21 after intranasal vaccination compared with intramuscular vaccination.
Trial designs and vaccine types
Two studies compare a nasal live attenuated influenza vaccine with an intramuscular inactivated influenza vaccine. In the VAXXAIR trial, the nasal vaccine is compared with a placebo nasal spray and with an intramuscular vaccine arm. The first trial specifically studies the immune response after a first and second dose of the nasal vaccine in children.
Main endpoints
The main endpoint in the children’s study is whether vaccine-strain shedding is present or absent in nasal lining fluid after vaccination. In VAXXAIR, the primary outcomes include antigen-activated CD4+ T-lymphocytes and mucosal antibody rises in respiratory secretions at several follow-up visits. In the antibody study, the main endpoint is the fold change in influenza-specific IgA levels in nasal fluid at day 21.
Why these trials matter
These studies try to understand how well influenza vaccines trigger mucosal immunity, which is the immune defense in the nose and airways. This is important because the nose and airway lining are the first places where influenza infection can start. The trials focus on immune markers rather than direct illness outcomes, helping researchers compare how different vaccination routes work in the body.