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A Clinical Trial of an Inactivated Quadrivalent Influenza Vaccine in Chinese Children Aged 3 to 8 Years

Phase 4
Conditions
Influenza
Interventions
Biological: Quadrivalent influenza vaccine
Registration Number
NCT05144464
Lead Sponsor
Jiangsu Province Centers for Disease Control and Prevention
Brief Summary

Routine annual influenza vaccination is recommended for all persons aged ≥6 months who do not have contraindications. For those aged 6 months through 8 years who have previously received ≥2 total doses of trivalent or quadrivalent influenza vaccine ≥4 weeks apart, they require only 1 dose of influenza vaccine. For those who have not previously received ≥2 doses of trivalent or quadrivalent influenza vaccine, they require 2 dose of influenza vaccine. but the evidence on how to select vaccine doses for quadrivalent influenza vaccine is limited in China. The study is a prospective, open-label comparison of the immunogenicity and reactogenicity of 1 versus 2 doses of an inactivated quadrivalent influenza vaccine in subjects of 3-8 years old with different history of influenza vaccination.

Detailed Description

Subjects receive 2 dosed of quadrivalent influenza vaccine 4 weeks apart.

Blood samples were obtained from children at 3 time points-before receipt of dose 1, 4 weeks after receipt of dose 1 and before dose 2, and 4 weeks after dose 2. Hemagglutination inhibition (HAI) antibody titers to the A/H3N2, A/H1N1, and B antigens included in the vaccine were measured at each time point

Recruitment & Eligibility

Status
UNKNOWN
Sex
All
Target Recruitment
240
Inclusion Criteria
  • Aged 3-8 years old
  • Healthy subjects judged from medical history and clinical examination
  • Subjects themselves or their guardians able to understand and sign the informed consent
  • Subjects themselves or their guardians can and will comply with the requirements of the protocol
  • Subjects have received ≥2 doses of trivalent or quadrivalent infuenza vaccine before enrollment (Doses need not have been received during same or consecutive seasons); Subjects have not received infuenza vaccine before enrollment
  • Subjects with temperature <=37.0°C on axillary setting
Exclusion Criteria
  • Subject who has a medical or family history of any of the following: allergic history, seizure, epilepsy, brain or mental disease
  • Subject who is allergic to any ingredient of the vaccine
  • Subject with damaged or low immune function which has already been known
  • Subject with acute febrile illness or infectious disease
  • Major congenital defects or serious chronic illness, including perinatal brain damage
  • Thrombocytopenia, blood coagulation disorder or bleeding difficulties with intramuscular injection
  • Subject who has serious allergic history
  • Subject who developed guillain-Barre syndrome post influenza vaccination
  • Any prior administration of immunodepressant or corticosteroids in last 6 months
  • Any prior administration of influenza vaccine in last 6 month
  • Any prior administration of blood products in last 3 months
  • Any prior administration of other research medicine/vaccine in last 30 days
  • Any prior administration of any attenuated live vaccine in last 14 days
  • Any prior administration of subunit or inactivated vaccines in last 7 days, such as pneumococcal vaccine
  • Any medical, psychological, social or other condition judged by investigator, that may interfere subject's compliance with the protocol or signature on informed consent for subject's guardian

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Quadrivalent influenza vaccineQuadrivalent influenza vaccineSubjects received 2 doses of 0.5 mL of quadrivalent influenza vaccine, 4 weeks apart. Each 0.5-ml dose contained 15 μg of hemagglutinin per strain.
Primary Outcome Measures
NameTimeMethod
Number of participants with Adverse Reactions (ARs)28 days after each vaccination

Frequency and severity of ARs for 28 days after each vaccination

the 95% confidence interval (CI) lower limit for Seroconversion Rate (SCR) of Hemagglutination inhibition (HAI) antibodies against each virus strain after 2nd vaccination ≥40%day 28 after dose 2

The lowest dilution used in the assay is 1/10. Seroconversion was defined as either a pre-vaccination HAI titer \< 1:10 and a post-vaccination titer ≥1:40 or a pre-vaccination titer ≥1:10 and ≥ four-fold increase in post-vaccination titer.

Secondary Outcome Measures
NameTimeMethod
Number of participants with Serious Adverse Events (SAE)6 months after the last vaccination

Frequency of SAEs for 6 months after the last vaccination

the 95% CI lower limit for seroprotection rates of HAI antibodies against each virus strain after 2nd vaccination≥70%day 28 after dose 2

A seroprotected subject is defined as a vaccinated subject with serum HAI titer≥ 1:40.

Geometric Mean Fold Increase (GMFI) of HAI titer against each virus strain after 2nd vaccination>2.5day 28 after dose 2

Hemagglutination inhibition (HAI) titers were used to calculate post-vaccination geometric mean fold increase (GMFI) against each virus strain

Number of participants with Adverse Events (AEs)28 days after each vaccination

Frequency and severity of AEs for 28 days after each vaccination

Trial Locations

Locations (1)

Pizhou City Center for Disease Control and Prevention

🇨🇳

Xuzhou, Jiangsu, China

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