Table of Contents
- Trial overview
- Who was studied
- What was measured
- Trial status and size
- Study design and phase
- Key terms explained
Trial overview
Two interventional studies investigated INFLUENZA INACTIVATED SPLIT VIRUS STRAIN A (H1N1) as part of influenza vaccine research in adults.[1][2] Both studies were designed to assess the immune response and safety of vaccine interventions in people with human influenza.[1][2]
Who was studied
The target population in both trials was adults 18 years of age and older.[1][2] The condition listed for both studies was Influenza, Human, which means the trials focused on influenza in people rather than in animals or in a lab-only setting.[1][2]
These studies did not describe children, pregnant people, or other special groups in the source data, so the trial population described here is limited to adults.[1][2]
What was measured
The main goal was to evaluate the humoral immune response, which means the antibody response made by the blood after the study intervention.[1][2] The studies measured antibody titer at Day 29, the fold increase in antibody titer from Day 1 to Day 29, seroconversion from Day 1 to Day 29, and seroprotection at Day 1 and Day 29.[1][2]
Safety was also a major focus.[1][2] The trials tracked 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 pre-dose and after dosing on Days 3, 8, and 29.[1][2]
Trial status and size
One study, NCT07204964, was Authorised and planned to enroll 960 participants.[2] The other study, 2025-522278-35-00, was Completed and enrolled 770 participants.[1]
Both studies were relatively large Phase 2 trials, which helps researchers collect more information about immune response and safety before moving to later development steps.[1][2]
Study design and phase
Both trials were interventional, meaning the researchers gave study vaccines and then observed the results.[1][2] Each study was in Phase 2, which is a stage used to learn more about how the vaccine performs in a larger group after earlier testing.[1][2]
The intervention lists included INFLUENZA INACTIVATED SPLIT VIRUS STRAIN A (H1N1) as part of trivalent influenza vaccine comparisons and related vaccine formulations, all given by intramuscular use.[1][2] The source data also included other influenza vaccine components and recombinant hemagglutinin products, but the trial focus remained the immune response and safety of the study interventions.[1][2]
Key terms explained
Antibody titer is a blood test measure of how much antibody is present.[1][2] Seroconversion means a person develops a measurable antibody response after the study intervention.[1][2] Seroprotection means the antibody level is considered high enough to suggest protection.[1][2]
Solicited events are symptoms that participants are asked to watch for and report, while unsolicited adverse events are any other unwanted health problems that come up during the study.[1][2] Serious adverse events are more severe health problems, and laboratory abnormalities are test results outside the normal range.[1][2]
