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

Phase 4
Completed
Conditions
Influenza
Interventions
Biological: Quadrivalent influenza vaccine
Registration Number
NCT05313893
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 monthsthrough 8 years who have previously received ≥2 total doses of trivalent orquadrivalent influenza vaccine ≥4 weeks apart, they require only 1 dose ofinfluenza vaccine. For those who have not previously received ≥2 doses oftrivalent or quadrivalent influenza vaccine, they require 2 dose of influenzavaccine. but the evidence on how to select vaccine doses for quadrivalentinfluenza vaccine is limited in China. The study is a prospective, open-labelcomparison of the immunogenicity and reactogenicity of 1 versus 2 doses ofan inactivated quadrivalent influenza vaccine in subjects of 3-8 years old withdifferent 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 receiptof dose 1, 4 weeks after receipt of dose 1 and before dose 2, and 4 weeksafter dose 2. Hemagglutination inhibition (HAI) antibody titers to the A/H3N2,A/H1N1, and B antigens included in the vaccine were measured at each timepoint

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
252
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 theinformed consent
  • Subjects themselves or their guardians can and will comply with therequirements of the protocol
  • Subjects have received ≥2 doses of trivalent or quadrivalent infuenzavaccine before enrollment (Doses need not have been received duringsame or consecutive seasons); Subjects have not received infuenzavaccine before enrollment
  • Subjects with temperature <=37.0°C on axillary setting
Exclusion Criteria
  • Any prior administration of other research medicine/vaccine in last 30 days
  • Any prior administration of influenza vaccine in last 6 month
  • Any prior administration of immunodepressant or corticosteroids in last 3 months
  • Any prior administration of blood products in last 3 months
  • Any prior administration of any attenuated live vaccine in last 14 days
  • Any prior administration of subunit or inactivated vaccines in last 7 days
  • Subject who developed guillain-Barre syndrome post influenza vaccination
  • Subject who is allergic to any ingredient of the vaccine
  • Subject with acute febrile illness or infectious disease
  • Thrombocytopenia, blood coagulation disorder or bleeding difficulties withintramuscular injection
  • Subject with damaged or low immune function which has already beenknown
  • Subject with congenital heart disease or other birth defects unsuitable for vaccination.
  • Subject with respiratory diseases (including pneumonia, tuberculosis, severe asthma, etc.), heart, liver and kidney diseases, mental disorders, or chronic infections.
  • Any medical, psychological, social or other condition judged byinvestigator, that may interfere subject's compliance with the protocol

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 quadrivalentinfluenza vaccine, 4 weeks apart. Each 0.5-ml dosecontained 15 μg of hemagglutinin per strain.
Primary Outcome Measures
NameTimeMethod
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 \< 1:10and a post-vaccination titer ≥1:40 or a pre-vaccination titer ≥1:10 and ≥ four-fold increase in post-vaccination titer.

Number of participants with Adverse Reactions (ARs)28 days after each vaccination

Frequency and severity of ARs for 28 days after each vaccination

Secondary Outcome Measures
NameTimeMethod
Number of participants with Adverse Events (AEs)28 days after each vaccination

Frequency and severity of AEs for 28 days after each vaccination

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

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.

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

Frequency of SAEs for 6 months after the last vaccination

Trial Locations

Locations (1)

Donghai County Center for Disease Control and Prevention

🇨🇳

Lianyungang, Jiangsu, China

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