Exploration on the Quadrivalent Influenza Vaccine Immunization Schedule for Children Aged 3-8 Years

NCT06095947 | Completed

• 1 other identifier: HL-SJLG-2021-Ⅳ-02
• Study Type: observational
• Target: 652
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this \[To evaluate the immunogenicity and safety of 1 - and 2-dose schedules of quadrivalent influenza vaccine (split virion) in healthy people with and without immunization history.\] is to \[aged 3-8 years\] in \[Healthy people\]. The main question\[s\] it aims to answer are: • \[To evaluate the immunogenicity of a two-dose schedule of quadrivalent influenza vaccine (quadrivalent influenza vaccine) in healthy population aged 3-8 years with or without vaccination history.\] •\[ To evaluate whether antibody levels are different 30 days after one dose of quadrivalent influenza vaccine versus two doses of quadrivalent influenza vaccine in healthy people aged 3-8 years with or without vaccination history.\]

Conditions

GCP

Outcome Measures

Primary Outcomes (2)

• evaluate the immunogenicity of 1-dose and 2-dose schedule in 3-8 years old healthy people with and without immunization history

  The lower limit of the 95% confidence interval (CI) of the seroconversion rate (SCR) of hemagglutination inhibition (HAI) antibodies against each virus strain after vaccination was ≥40%. The lowest dilution used in the assay was 1 in 10. Seroconversion was defined as a prevaccination HAI titer of \<1:10 and a postvaccination titer of ≥1:40 or a prevaccination titer of ≥1:10 and a 4-fold or greater increase in titer after vaccination.

  Blood samples were collected before immunization, 30 days after the first dose (before the second dose) and 30 days after the first dose for influenza virus HI antibodies.

• evaluate the safety of one dose and two doses schedule in children aged 3-8 years

  The occurrence of adverse reactions/events after each dose of vaccination was observed. The incidence of ① total adverse reactions/events, ② incidence of grade 3 or above adverse reactions/events and SAE, ③ incidence of adverse reactions/events severity classification, ④ incidence of adverse reactions/events by type (inoculation site and systemic, SOC, PT) and incidence of adverse reactions/events severity classification were calculated.

  The safety was observed until 6 months after the full course of immunization

Secondary Outcomes (1)

• Differences in antibody levels 30 days after one dose and two doses of quadrivalent influenza vaccine among healthy people aged 3-8 years with or without vaccination history.

  Blood samples were collected before immunization, 30 days after the first dose (before the second dose) and 30 days after the first dose for influenza virus HI antibodies.

Study Arms (2)

There was an immunological history group

l Children who have received two or more doses of influenza vaccine (4 weeks apart) before the influenza season (2 doses of influenza vaccine do not need to be administered in the same epidemic season or consecutive epidemic season, and can be interpreted as children who have received two or more cumulative doses).

Biological: Influenza Vaccine (Split Virion), Inactivated, Quadrivalent

There was no immunological history group

l Children who have not received or previously received \<2 doses of influenza vaccine before the epidemic season.

Biological: Influenza Vaccine (Split Virion), Inactivated, Quadrivalent

Interventions

Influenza Vaccine (Split Virion), Inactivated, Quadrivalent BIOLOGICAL

A total of 652326 healthy children with immunization history and no immunization history aged 3-8 years who met the program requirements received two doses of normally commercially available quadrivalent influenza vaccine according to the 0,30-day procedure.

There was an immunological history group; There was no immunological history group

Eligibility Criteria

• Age: 3 Years - 8 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)
• Sampling Method: Probability Sample

Study Population

Healthy people aged 3-8 years old

You may qualify if:

• years old;
• The legal guardian / authorized agent gives the informed consent and voluntarily signs the informed consent to comply with the requirements of the clinical trial protocol;
• Medical history, physical examination and clinical diagnosis, who to the immunization of this product.
• children who have received two or more doses of influenza vaccine (4 weeks apart) before the season of this influenza epidemic (2 doses of influenza vaccine do not need to be vaccinated in the same epidemic season or consecutive epidemic season, but can be interpreted as children who have received two or more cumulative shots).
• History of l No immunization: children who had not been vaccinated or had previously received \<2 doses of influenza vaccine before the influenza season.

You may not qualify if:

• Any influenza vaccine (registered or research) within 6 months prior to enrollment; or planned for use during the study period;
• Use of immunoglobulin and / or any blood products within 3 months prior to enrollment; or planned for use during the study (before blood sampling);
• Patients with a history of Guillain-Barre syndrome; l Acute disease, severe chronic disease, acute onset of chronic disease, cold;
• Uncontrolled epilepsy;
• Has been diagnosed with congenital or acquired immunodeficiency, HIV infection, lymphoma, leukemia, or other autoimmune diseases;
• those receiving immune booster or inhibitor treatment within 3 months (continuous oral or drip for more than 14 days);
• History of abnormal coagulation function (such as lack of coagulation factors, coagulation disease);
• Primary and secondary impaired immunity (history of thyroid, pancreas, liver and spleen resection);
• A history of severe allergic reactions to vaccination;
• live attenuated vaccine within 14 days before vaccination and other vaccines within 7 days before vaccination;
• Is in or recently planning to participate in other clinical trials;
• Other conditions judged by the investigator as not suitable for participation in this clinical trial.
• Patients with severe allergic reactions after the previous dose of vaccination;

Sponsors & Collaborators

• Hualan Biological Bacterin Co. Ltd.: lead

Study Sites (1)

Kou Zengqiang

Jinan, Shandong, 250000, China

Location

Biospecimen

Retention: SAMPLES WITH DNA

Approximately 3ml of blood was collected on day 0, day 30 (before the second dose of inoculation), and day 60

MeSH Terms

Interventions

Influenza Vaccines

Intervention Hierarchy (Ancestors)

Viral Vaccines; Vaccines; Biological Products; Complex Mixtures

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 25, 2023
• First Posted: October 23, 2023
• Study Start: September 15, 2021
• Primary Completion: February 6, 2023
• Study Completion: February 28, 2023
• Last Updated: September 15, 2025

Record last verified: 2025-09

Locations

CN (1)