A Clinical Trial of Influenza Virus Split Vaccine for Individuals Aged 60 Years and Above

A Randomized, Double-blind, Controlled Phase I Clinical Trial to Evaluate the Safety and Immunogenicity of the Influenza Virus Split Vaccine for Individuals Aged 60 Years and Above

This is a randomized, blinded, controlled phase I clinical trial with a total of 120 participants aged ≥ 60 years. Experimental group: Influenza virus split vaccine (0.7mL/vial), control group 1: Influenza virus split vaccine, control group 2: placebo group. The three groups were recruited at a ratio of 1:1:1, and 40 individuals were randomly vaccinated in each group. Each person was injected with one dose of the vaccine into the deltoid muscle of the upper arm. Participants in each study group are required to undergo laboratory indicator tests before and on the 4th day after vaccination.

Study Overview

• Status: Recruiting
• Conditions: Influenza
• Intervention / Treatment: Biological: Influenza virus split vaccine (0.7mL/vial); Biological: Influenza virus split vaccine; Biological: Phosphate buffer solution (PBS)

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Chaorong Xu; Phone Number: 86-021-62800991; Email: xuchaorong@sinopharm.com
• Study Contact Backup: Name: Yang Liu; Phone Number: 86-010-65777702; Email: liuyang30@sinopharm.com

Study Locations

• China
  • Hubei
    • Wuhan, Hubei, China
      • Recruiting
      • Danjiangkou Disease Prevention and Control Center
      • Contact: Yunbo Pan; Phone Number: 86-15897801799; Email: 2792320450@qq.com

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Age over 60 years old, gender not limited, and able to provide legal identification;
• Volunteers voluntarily participate in the study and sign an informed consent form;
• Volunteers have the ability to understand research procedures, use thermometers, scales, and fill out diary cards as required, and can participate in all planned follow-up visits.

Exclusion Criteria:

• On the day of enrollment, the axillary temperature was ≥ 37.3 ℃;
• Those who have had influenza in the past 6 months or meet the definition of influenza like cases;
• Have received any influenza vaccine within the past 12 months or have planned to receive any influenza vaccine during the study period;
• Allergies to any components of the research vaccine, history of allergic reactions to the use of gentamicin sulfate, history of severe allergies to any vaccine/drug, or history of asthma;
• Suffering from a serious illness that prevents the completion of the entire study; Within 3 days prior to vaccination, there is an acute illness or an acute exacerbation of a chronic disease;
• Have used antipyretic or analgesic drugs or anti allergic drugs within 3 days before vaccination;
• Have received any vaccine within 2 weeks prior to vaccination;
• Have received immunosuppressive therapy or other immunomodulatory drugs within 6 months prior to receiving the experimental vaccine, For example, immunosuppressive doses of glucocorticoids, monoclonal antibodies, thymosin, interferon, etc., or planned to receive such treatment within one month after the first dose of vaccination to full immunization, but local medication is allowed;
• Suffering from congenital or acquired immunodeficiency, human immunodeficiency virus (HIV) infection, lymphoma, leukemia, or other autoimmune diseases;
• Suffering from serious chronic diseases, serious cardiovascular diseases, such as hypertension that cannot be controlled by drugs, diabetes that cannot be controlled by drugs or has serious complications, liver and kidney diseases, pulmonary edema, malignant tumors, etc;
• Have received blood or blood related products within the past 6 months;
• Individuals with progressive neurological disorders, including a history of seizures, epilepsy, encephalopathy, Guillain Barr é syndrome, psychiatric or family history;
• Have a history of abnormal coagulation function and have been using anticoagulants within 3 weeks before vaccination;
• Patients with splenectomy, functional splenectomy, splenectomy, or other important organ resection or partial resection;
• Plan to move before the end of the study or leave the local area for a long time during the scheduled study visit;
• Currently or recently planning to participate in other clinical trials;
• Abnormal laboratory test indicators before vaccination;
• Researchers determine any situation that is not suitable for clinical trials.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Experimental group; Influenza virus split vaccine, with a specification of 0.7mL/bottle	Biological: Influenza virus split vaccine (0.7mL/vial); Influenza virus split vaccine, with a specification of 0.7mL/bottle, containing 60 μ g of hemagglutinin from H1N1, H3N2, and B influenza virus strains each
Active Comparator: Control group 1; Influenza virus split vaccine, with a specification of 0.5mL/bottle	Biological: Influenza virus split vaccine; Influenza virus split vaccine, with a specification of 0.5mL/bottle, containing 15 μ g of hemagglutinin from H1N1, H3N2, and B influenza virus strains each
Placebo Comparator: Control group 2; Phosphate buffer solution	Biological: Phosphate buffer solution (PBS); PBS, with a specification of 0.5mL/bottle.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Unsolicited Adverse Events	Other adverse events that occurred among participants within 0-30 days after vaccination, in addition to the solicited adverse events.	30 days after vaccination
Solicited Adverse Events (AEs)	Adverse events defined by the protocol that occurred to the participant during 0-7 days after vaccination.	7 days after vaccination
Serious Adverse Events (SAE)	That is serious adverse events, any serious adverse events that occurred to the participant during the study period.	6 months after vaccination

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Seroconversion rate	30 days after vaccination of all participants with the experimental vaccine or control vaccines, the HI antibody seroconversion rate against any subtype of influenza virus in the experimental vaccine group or the control vaccine groups.	30 days after vaccination
Ratio of ≥1:40	30 days after vaccination of all participants with the experimental vaccine or control vaccines, the ratio of HI antibody titers ≥ 1:40 against any subtype of influenza virus in the experimental vaccine group or the control vaccine groups.	30 days after vaccination
Geometric mean titer (GMT)	30 days after vaccination of all participants with the experimental vaccine or control vaccines, GMT of HI antibodies against any subtype of influenza virus in the experimental vaccine group or the control vaccine groups.	30 days after vaccination
Geometric mean increase (GMI)	30 days after vaccination of all participants with the experimental vaccine or control vaccines, GMI of HI antibodies against any subtype of influenza virus in the experimental vaccine group or the control vaccine groups.	30 days after vaccination

Collaborators and Investigators

• Sponsor: Shanghai Institute Of Biological Products
• Investigators: Principal Investigator: Yeqing Tong, Hubei Provincial Center for Disease Control and Prevention

Study record dates

Study Major Dates

• Study Start (Actual): December 16, 2025
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): August 31, 2026

Study Registration Dates

• First Submitted: December 11, 2025
• First Submitted That Met QC Criteria: December 11, 2025
• First Posted (Estimated): December 24, 2025

Study Record Updates

• Last Update Posted (Actual): January 14, 2026
• Last Update Submitted That Met QC Criteria: January 13, 2026
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Safety; Immunogenicity; The elderly; Influenza virus split 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: SIBP-V05-001

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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