Preliminary Safety Assessment of a Quadrivalent Subunit Influenza Vaccine in China

July 16, 2026 updated by: Ab&B Bio-tech Co., Ltd.JS

Preliminary Safety Assessment of a Quadrivalent Subunit Influenza Vaccine Following Post-Marketing in China: An Open-Label, Single-Arm Clinical Trial

This study evaluates the safety of the quadrivalent subunit influenza vaccine in individuals aged 3 years and older in Jiangsu Province, China. The primary objectives are to assess the occurrence of very rare adverse reactions (incidence <0.01%), investigate the incidence of cerebral infarction following vaccination, and evaluate the incidence of systemic adverse events among participants aged 9 to 17 years.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This is an open-label, single-arm, non-controlled, real-world safety study of the quadrivalent subunit influenza vaccine, designed to systematically track and evaluate the overall safety profile following vaccine administration.

The core objectives of this study are as follows:

  1. To assess the occurrence of rare adverse reactions with an incidence rate of less than 0.01% after vaccination;
  2. To investigate the incidence of cerebral infarction events following receipt of the study vaccine;
  3. To evaluate the incidence of systemic adverse events after vaccination among participants aged 9 to 17 years.

A total of 3,105 eligible participants aged 3 years and older who voluntarily receive the vaccine will be enrolled. All enrolled participants will be administered a single 0.5 mL intramuscular dose of the quadrivalent influenza subunit vaccine.

The safety monitoring protocol is arranged as follows:

  1. 30-minute immediate observation: On-site monitoring will be conducted at the vaccination clinic immediately after injection to detect immediate adverse reactions.
  2. 28-day systematic safety follow-up: Participants will perform daily self-monitoring of adverse events within 28 days after vaccination. Investigators will conduct two on-site centralized follow-up visits on Day 7 and Day 28 post-vaccination respectively, to verify and collect adverse event data.
  3. 6-month serious adverse event monitoring: The occurrence of serious adverse events will be monitored via spontaneous reporting by participants within 6 months after vaccination.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
3105

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • China
    • Jiangsu
      • Dongtai, Jiangsu, China, 224200
        • Dongtai Center for Disease Control and Prevention
      • Lianshui, Jiangsu, China, 223400
        • Lianshui County Center for Disease Control and Prevention

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Child
  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

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

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: The quadrivalent influenza subunit vaccine Group
receive a single 0.5 mL intramuscular dose of the quadrivalent influenza subunit vaccine
Biological: quadrivalent subunit influenza vaccine
one dose of quadrivalent subunit influenza vaccine

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Adverse Events (AEs)
Time Frame: 30 minutes, 7 days, and 28 days after vaccination
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）
Time Frame: 30 minutes, 7 days, and 28 days after vaccination
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)
Time Frame: 6 months after vaccination
Occurrence of serious adverse events (SAEs) within 6 months after vaccination; Incidence of new adverse reactions following vaccination； Incidence of cerebral infarction following vaccination； Incidence of systemic adverse reactions following vaccination in individuals aged 9 to 17 years
6 months after vaccination

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Ab&B Bio-tech Co., Ltd.JS

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Jiangsu Province Centers for Disease Control and Prevention

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 15, 2024

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
May 29, 2025

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
May 29, 2025

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
July 14, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 14, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
July 17, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
July 20, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 16, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • CTR20244333

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Influenza Vaccine

Clinical Trials on quadrivalent subunit influenza vaccine

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings