Safety Study of Quadrivalent Subunit Influenza Vaccine in People Aged 3 Years and Older

A Safety Study of Quadrivalent Subunit Influenza Vaccine in a Large-Scale Population Aged 3 Years and Older

This study evaluates the safety of the quadrivalent subunit influenza vaccine following its post-marketing widespread use in individuals aged 3 years and older, aiming to assess the occurrence of very rare adverse reactions (with an incidence rate of <0.01%).

Study Overview

• Status: Completed
• Conditions: Influenza Vaccine
• Intervention / Treatment: Biological: quadrivalent subunit influenza vaccine

Detailed Description

This is a large-scale, multicenter, open-label, single-arm, non-controlled real-world safety observational study following influenza vaccination. It is designed to assess the occurrence of very rare adverse reactions (incidence <0.01%) following vaccination with a quadrivalent influenza subunit vaccine and to demonstrate its superior safety profile.

A total of 42,881 participants aged 3 years and above were enrolled. Each received a single 0.5 ml dose of the quadrivalent influenza subunit vaccine. Safety monitoring included immediate observation for 30 minutes post-vaccination and systematic surveillance over the subsequent 28 days. Data on adverse events (AEs) and serious adverse events (SAEs) were collected during two time intervals: from 30 minutes to 7 days (inclusive) and from 8 to 28 days (inclusive) after vaccination. Any newly identified adverse reactions during the study period were also recorded.

• Study Type: Observational
• Enrollment (Actual): 42881

Contacts and Locations

Study Locations

• China
  • Gansu
    • Lanzhou, Gansu, China, 730000
      • Gansu Provincial Center for Disease Control and Prevention
  • Guangdong
    • Guangzhou, Guangdong, China, 510440
      • Guangdong Provincial Institute of Biological Products and Materia Medica
  • Hubei
    • Wuhan, Hubei, China, 430079
      • Hubei Provincial Center for Disease Control and Prevention
  • Jiangsu
    • Nanjing, Jiangsu, China, 210009
      • Jiangsu Provincial Academy of Preventive Medicine
  • Qinghai
    • Xining, Qinghai, China, 810007
      • Qinghai Provincial Center for Disease Control and Prevention
  • Shandong
    • Jinan, Shandong, China, 250014
      • Shandong Center for Disease Control and Prevention
  • Shanghai Municipality
    • Shanghai, Shanghai Municipality, China, 200336
      • Shanghai Municipal Center for Disease Control and Prevention
  • Xinjiang Uygur Autonomous Region
    • Ürümqi, Xinjiang Uygur Autonomous Region, China, 830002
      • Xinjiang Uygur Autonomous Region Center for Disease Control and Prevention

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

Healthy individuals aged 3 years or above

Description

Inclusion Criteria

1. Healthy individuals aged 3 years or above.
2. The participant (and/or their guardian/legal representative) has provided informed consent, voluntarily agreed to participate, signed the Informed Consent Form, and is able to comply with the requirements of this study protocol.

Exclusion Criteria

1. Individuals with a known allergy to any component of the vaccine, including eggs, excipients, formaldehyde, or Triton N-101.
2. Individuals suffering from an acute illness, severe chronic disease, an acute exacerbation of a chronic disease, common cold, or fever.
3. Individuals with uncontrolled epilepsy or other progressive neurological disorders, or a history of Guillain-Barré syndrome.
4. Any other condition considered by the investigator as inappropriate for participation in this study.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
One dose Vaccine in aged 3 years and older	Biological: quadrivalent subunit influenza vaccine; one dose of quadrivalent subunit influenza vaccine

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Adverse Events (AEs)	Occurrence of adverse events (AEs) within 30 minutes, 7 days, and 28 days after vaccination	30 minutes, 7 days, and 28 days after vaccination
Adverse Drug Reactions（ADR）	Incidence of known adverse drug reactions (ADRs) within 30 minutes, 7 days, and 28 days after vaccination	30 minutes, 7 days, and 28 days after vaccination
Serious Adverse Events (SAEs)	Occurrence of serious adverse events (SAEs) within 28 days after vaccination; Incidence of new adverse reactions following vaccination	28 days after vaccination

Collaborators and Investigators

• Sponsor: Ab&B Bio-tech Co., Ltd.JS
• Collaborators: Guangdong Provincial Institute of Biological Products And Materia Medica; Hubei Provincial Center for Disease Control and Prevention; Shandong Province Centers for Disease Control and Prevention; Shanghai Municipal Center for Disease Control and Prevention; Jiangsu Provincial Academy of Preventive Medicine; Xinjiang Uygur Autonomous Region Center for Disease Control and Prevention; Gansu Provincial Center for Disease Control and Prevention; Qinghai Provincial Center for Disease Control and Prevention

Study record dates

Study Major Dates

• Study Start (Actual): October 30, 2023
• Primary Completion (Actual): April 28, 2025
• Study Completion (Actual): April 28, 2025

Study Registration Dates

• First Submitted: December 30, 2025
• First Submitted That Met QC Criteria: December 30, 2025
• First Posted (Estimated): January 12, 2026

Study Record Updates

• Last Update Posted (Estimated): January 12, 2026
• Last Update Submitted That Met QC Criteria: December 30, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Safety; Quadrivalent Subunit Influenza Vaccine
• Additional Relevant MeSH Terms: Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases; Influenza, Human
• Other Study ID Numbers: CDRZ20234001-2

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No