Immunogenicity and Safety of DTaP or DT Vaccine in 6 Year Old Children ( DTaP/DT )

Study Overview
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Brief Summary
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This study is to evaluate the immunogenicity and safety of DTaP or DT given in children aged 6 years.

Detailed Description
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A phase 4 trial was conducted in Zhejiang Province aimed to evaluate the immunogenicity and safety of DTaP or DT in children aged 6 years. DTaP and DT are produced by Chengdu Institute of Biological Products Co., Ltd. Participants will be recruited and randomly divided into two groups to receive DTaP or DT in 1:1 ratio. Two blood samples were taken on Day 0 (pre-vaccination) and Day 28 42 (after-vaccination) for test antibody against pertussis, diphtheria and tetanus. Adverse events and serious adverse events were actively collected by staff within 28 days of vaccination.

Official Title
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Immunogenicity and Safety of Adsorbed Diphtheria, Tetanus, Acellular Pertussis Combined Vaccine or Adsorbed Diphtheria Tetanus Combined Vaccine in 6 Years Old Children#a Randomized, Controlled Clinical Study

Conditions
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Vaccine Reaction

Intervention / Treatment
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* Biological: vaccinate with DTaP
* Biological: vaccinate with DT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1. Participants aged ≥ 6 on the day of enrollment; 2. Informed consent should be signed and dated by the participants; 3. The participant's legal guardian is able to attend all planned follow-up visits and comply with all study procedures; 4. The participants have received 4 doses of acellular TDap vaccine and have not received any immunization agents related to diphtheria, tetanus, and pertussis in the past 3 years; 5. The participant has no diease history of pertussis, diphtheria or tetanus; 6. ≥ 14 days interval between the last vaccination; 7. Body temperature was ≤37.3℃. Exclusion Criteria: 1、Being allergic to any component of vaccines ； 2、A history of severe allergic reactions to any vaccine (for example acute allergic reaction, angioneurotic edema, dyspnea, etc）； 3、Having a history or family history of convulsions, encephalopathy, psychosis, uncontrolled epilepsy and other progressive neurological diseases; 4、Participants are suffering from immunodeficiency, receiving immunosuppressant therapy (oral steroid hormones) during treatment for malignancy, or having low immunity due to HIV, or having congenital immune disorders in close family members; 5、Injection of non-specific immunoglobulin within 1 month before enrollment; 6、Participants are suffering from acute febrile diseases and infectious diseases; 7、A history of clearly diagnosed thrombocytopenia or other clotting disorders that may contraindicate subcutaneous injection; 8、Participants with severe chronic diseases or acute episodes of chronic diseases; 9、Participants with infectious, suppurative and allergic skin diseases; 10、Other Participants whose physical conditions, as determined by the investigator, are not suitable for inclusion in clinical studies.

Ages Eligible for Study
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Minimum Age: 72 Months
Maximum Age: 84 Months

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Group A<br>Group with DTap vaccination produced by Chendu Institute of Biological Products Co., Ltd | Biological: vaccinate with DTaP<br>* vaccinate with DTaP<br>|
| Experimental: Group B<br>Group with DT vaccination | Biological: vaccinate with DT<br>* vaccinate with DT<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Seroconversion rates of the vaccination | Defined as any positive antibody response against pertussis，diphtheria，tetanus in children who were seronegative prior to the vaccination, or at least a fourfold increase in antibody levels against pertussis for children who had pre-existing positive antibodies | 28-42 days after the dose of DTaP or DT | 
| Seropositive rates after the vaccination | The percentage of participants with positive antibody against pertussis，diphtheria and tetanus. | 28-42 days after the dose of DTaP or DT | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety of the DTaP or DT vaccine immunization | The occurrence of adverse events for vaccination administered at age 6 using DTaP or DT | 28 days after the vaccination | 
| Geometric mean antibody concentrations before the vaccination | The GMC against pertussis，diphtheria and tetanus | before the dose of DTaP or DT | 
| Geometric mean antibody concentrations after the vaccination | The GMC against pertussis，diphtheria and tetanus | 28-42 days after the dose of DTaP or DT | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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immunogenicity，safety，DTap，DT