Skip to content

A Phase III Clinical Trial of Quadrivalent Influenza Vaccine in Healthy Subjects Aged 6 to 35 Months

An Randomized, Double-blind, Controlled Phase III Clinical Trial to Evaluate the Safety and Immunogenicity of Quadrivalent Influenza Vaccine in Healthy Subjects Aged 6 to 35months

Status
Completed
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT06049927
Enrollment
3300
Registered
2023-09-22
Start date
2023-09-16
Completion date
2024-05-23
Last updated
2025-08-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Seasonal Influenza

Brief summary

A phase III clinical trial of the study of quadrivalent influenza vaccine developed by Sinovac Biotech will be conducted in Chinese children aged 6 to 35 months. The trial is an randomized, double-blind and active controlled study. The objective of this study is to evaluate the Immunogenicity and safety of the vaccine.

Detailed description

A phase III clinical trial of the study of quadrivalent influenza vaccine developed by Sinovac Biotech will be conducted in Chinese children aged 6 to 35 months. The trial is an randomized, double-blind and active controlled study. The objective of this study is to evaluate the safety and immunogenicity of quadrivalent influenza vaccine(0.25ml and 0.5ml) manufactured by Sinovac Biotech Co., Ltd in healthy infants aged from 6 to 35 months. A total of 3300 subjects will be enrolled. The subjects will be randomly assigned to 4 groups in a 2:2:1:1 ratio and subjects will receive two doses of quadrivalent influenza vaccine(0.25ml or 0.5ml) or trivalent influenza vaccine(BV or BY), respectively, according to the immunization schedule of day 0,28 in each group.

Interventions

7.5 ug hemagglutinin (HA) of each of the four influenza strains in 0.25 mL of sodium chloride, disodium hydrogen phosphate, sodium dihydrogen phosphate per njection.The routine of administration is Intramuscular injection into deltoid region.And the immunization schedule is two doses on day 0, 28.

15 ug hemagglutinin (HA) of each of the four influenza strains in 0.5 mL of sodium chloride, disodium hydrogen phosphate, sodium dihydrogen phosphate per njection.The routine of administration is Intramuscular injection into deltoid region.And the immunization schedule is two doses on day 0, 28.

7.5μg inactivated influenza antigen (H1N1, H3N2, Victoria) of each of the trivalent influenza vaccine in 0.25 mL of sodium chloride, disodium hydrogen phosphate, sodium dihydrogen phosphate per injection.The routine of administration is Intramuscular injection into deltoid region. And the immunization schedule is two doses on day 0, 28.

7.5μg inactivated influenza antigen (H1N1, H3N2, and Yamagata) of each of the trivalent influenza vaccine in 0.25 mL of sodium chloride, disodium hydrogen phosphate, sodium dihydrogen phosphate per injection.The routine of administration is Intramuscular injection into deltoid region.And the immunization schedule is two doses vaccine on day 0, 28.

Sponsors

Sinovac Biotech Co., Ltd
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
6 Months to 35 Months
Healthy volunteers
Yes

Inclusion criteria

* Healthy infants aged 6-35 months; * Proven vaccination certificate and birth certificate; * The subjects' guardians can understand and voluntarily sign the informed consent form.

Exclusion criteria

* Received any circulating seasonal influenza vaccine prior to enrollment or had an influenza vaccine schedule during the study; * Suffering from seasonal influenza in the past 6 moths; * Axillary temperature \>37.0°C; * History of allergy to the vaccine or vaccine components, or serious adverse reactions to the vaccine, such as urticaria, dyspnea, angioedema and asthma; * Congenital malformations or developmental disorders, genetic defects, severe malnutrition, etc.; * Severe chronic diseases(Such as down syndrome, diabetes, sickle cell anaemia or neurological disorders); * Severe neurological disease (epilepsy, convulsions or convulsions) or mental illness; * Autoimmune disease (such as systemic lupus erythematosus) or immunodeficiency / immunosuppression (such as HIV, after organ transplantation) * Thyroid disease or history of thyroidectomy, asplenia,functional asplenia, asplenia or splenectomy resulting from any condition; * Diagnosed abnormal blood coagulation function (eg, lack of blood coagulation factors, blood coagulopathy, abnormal platelets) or obvious bruising or blood coagulation; * Continuous use of corticosteroids or other immunosuppressive agents for ≥ 14 days within the past 6 months (excluding allergic rhinitis corticosteroid spray therapy, acute noncomplicated dermatitis superficial corticosteroid therapy) and cytotoxic therapy in the past 6 months; * Acute diseases or acute exacerbation of chronic diseases in the past 3 days; * Receipt of blood products within in the past 3 months; * Receipt of other investigational drugs in the past 30 days; * Receipt of attenuated live vaccines in the past 14 days; * Receipt of inactivated or subunit vaccines in the past 7 days; * Participated in other clinical trials before enrollment and in the follow-up period, or plans to participate in other clinical trials during the clinical trial; * According to the investigator's judgment, the subject has any other factors that are not suitable for participating in the clinical trial

Design outcomes

Primary

MeasureTime frameDescription
Seroconversion rates of HI antibody28 days after full schedule immunizationAnti-influenza antibodies were measured using HAI assay for 4 strains: H1N1, H3N2, B Victoria and B Yamagata. Seroconversion was defined as pre-vaccination titer \<1:10 and post-vaccination titer ≥1:40, and Significant increase was defined as pre-vaccination titer≥1:40 and ≥ 4-fold increase of post-vaccination titer.
Geometric Mean Titers (GMTs) of HI antibody28 days after full schedule immunizationAnti-influenza antibody levels were measured using hemagglutination inhibition (HAI) assay for 4 strains: H1N1, H3N2, B Victoria, B Yamagata.
Number of Participants With Seroprotection to Influenza Vaccine Antigens28 days after full schedule immunizationAnti-influenza antibodies were measured using HAI assay for 4 strains: H1N1, H3N2, B Victoria and B Yamagata. Seroprotection was defined as an antibody titer ≥1:40 at pre-vaccination and at post-final vaccination.

Secondary

MeasureTime frameDescription
Incidence of Serious adverse eventsSince the beginning of vaccination until 6 months after the last doseIncidence of serious adverse events from beginning of vaccination until 6 months after the last dose
Incidence of adverse reactions0-30 days after each doseIncidence of adverse reaction 0-30 days after each dose
Incidence of AESIsince the beginning of vaccination until 6 months after the last doseIncidence of AESI since the beginning of vaccination until 6 months after the last dose
GMIs of HI antibody28 days after full schedule immunizationAnti-influenza antibody were measured using hemagglutination inhibition (HAI) assay for 4 strains: H1N1, H3N2, B Victoria, B Yamagata. GMI is the increase fold of GMT post vaccination compared with pre vaccination

Countries

China

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026