In short
Clinical trials investigating INFLUENZA INACTIVATED SPLIT VIRUS STRAIN A (H3N2) are studying how well influenza vaccine options work and how safe they are in adults 18 years and older. These studies focus on immune response, safety, and reactogenicity, which means how often short-term reactions happen after vaccination.
Key points
- Two Phase 2 clinical trials are studying influenza vaccine interventions that include INFLUENZA INACTIVATED SPLIT VIRUS STRAIN A (H3N2) in adults 18 years and older. The trials focus on Influenza, Human and look at both immune response and safety. Main endpoints include antibody titer, seroconversion, seroprotection, and fold increase in antibodies by Day 29. Safety is tracked through local and systemic events, adverse events, serious adverse events, special safety events, medically attended events, and lab abnormalities. One trial is completed with 770 participants, and one is authorised with 960 participants.
Overview of the trials
These clinical trials are studying influenza vaccine interventions that include INFLUENZA INACTIVATED SPLIT VIRUS STRAIN A (H3N2) as part of the influenza vaccine mix. The studies are focused on Influenza, Human and are designed to evaluate both immune response and safety.
Both trials are Phase 2 studies, which means they test how well the study interventions work and continue to watch safety in a larger group of people. The trial data show one study as completed and the other as authorised.
Who the trials are for
The target population in both studies is adults 18 years of age and older. No other age groups are described in the trial data, so the information here applies only to adults.
The studies compare different vaccine products, including the influenza inactivated split virus strain A (H3N2) component and other influenza vaccine formulations listed in the trial records. The source data do not give additional participant rules such as sex limits, health requirements, or exclusion criteria.
Study design and trial phase
Both studies are interventional, meaning the researchers give a study intervention and then measure the results. This design is used to see whether the vaccine response and safety profile meet the study goals.
The first trial enrolled 770 participants and was completed. The second trial enrolled 960 participants and is authorised. Together, these studies show a fairly large adult testing program for influenza vaccine evaluation.
What the trials measure
The main efficacy-related outcomes are antibody measures at Day 29, including antibody titer, fold increase in titer from Day 1 to Day 29, seroconversion, and seroprotection. These are blood-based markers that help show whether the body made an immune response after the study intervention.
The safety outcomes include solicited administration site or systemic events within 7 days, unsolicited adverse events within 28 days, serious adverse events within 6 months, adverse events of special interest within 6 months, medically attended adverse events within 6 months, and laboratory abnormalities at several time points. In simple terms, the studies track both short-term reactions and longer-term safety signals after vaccination.
The brief summaries say the studies aim to evaluate the humoral immune response and the safety and reactogenicity profile of the study interventions. Humoral immune response means the antibody response in the blood.
Trial list
- 2025-522278-35-00 — Phase 2, completed, 770 adults, focused on influenza immune response and safety.
- NCT07204964 — Phase 2, authorised, 960 adults, focused on influenza immune response and safety.
What these results mean for patients
For patients, these trials are mainly about learning whether the influenza vaccine study options can produce a strong antibody response in adults and whether they are safe to use. The data do not report final clinical protection against influenza illness in the text provided, so the main results here are immune markers and safety checks.
Because the studies are in adults 18 years and older, the findings are most relevant to adult influenza vaccination research. The trial records also show that the researchers are watching for both common short-term events and less common longer-term safety outcomes.