Immunogenicity of 2 Versus 3 Doses of Combined Hepatitis B Vaccines in 2-18 Months Old Children

Study Overview
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Brief Summary
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The main objective of this study is to compare the immunogenicity of the hepatitis B component in children vaccinated with (I) two doses of Infanrix-hexa administered at 2 and 12 months of age versus (II) one dose of Infanrix-hexa and one dose of Twinrix administered respectively at 2 and 12 months of age versus (III) three doses of Infanrix-hexa administered at 2, 4 and 18 months of age (comparator).

Detailed Description
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In the province of Quebec, Canada, hepatitis B vaccination of infants involves three doses of vaccine, 2, 4 and 18 months of age. However, in the current epidemiological context (virtual absence of new cases in young Quebecers) and taking into account scientific data which consistently show a high immunogenicity and efficacy of two doses of hepatitis B vaccine, the relevance of the second dose given at the age of 4 months is questionable. this study is designed to compare the immunogenicity of the hepatitis B component in children vaccinated with (I) two doses of Infanrix-hexa administered at 2 and 12 months of age versus (II) one dose of Infanrix-hexa and one dose of Twinrix administered respectively at 2 and 12 months of age versus (III) three doses of Infanrix-hexa administered at 2, 4 and 18 months of age (comparator).

Official Title
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Clinical Trial to Assess Immunogenicity of 2 Versus 3 Doses of Hepatitis B Vaccines When Administered to Children Aged 2 to 18 Months

Conditions
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Hepatitis B

Intervention / Treatment
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* Biological: Infanrix-hexa, Twinrix-Junior


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Comparator group : have received 3 doses of Infanrix-hexa as part of the regular vaccination program at the age of 2, 4 and 18 months. • Study groups: have received 1 dose of Infanrix-hexa as part of the regular vaccination program at the age of 2 months. Exclusion Criteria: Have received other doses of hepatitis B vaccine; Be considered immunosuppressed; Have an autoimmune disease; Have contraindications to HBV vaccination, as defined in the Quebec Immunization Protocol; Have a bleeding disorder; Be significantly delayed in development; Have or plan to participate in other clinical studies with vaccines or products not approved in Canada; Have presented a serious clinical condition to the vaccines administered as part of the study.

Ages Eligible for Study
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Minimum Age: 2 Months
Maximum Age: 19 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
Interventional Model Description: Randomised 1:1 for 2 study groups. Non-randomised for comparator group.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Infanrix-hexa+Infanrix-hexa+Infanrix-hexa<br>Children vaccinated at the age of 2, 4 and 18 months with a standard dose of Infanrix-hexa | Biological: Infanrix-hexa, Twinrix-Junior<br>* Vaccines administrated according to product monographs' recommendations<br>|
| Experimental: Infanrix-hexa+Infanrix-hexa<br>Children vaccinated at the age of 2 and 18 months with a standard dose of Infanrix-hexa | Biological: Infanrix-hexa, Twinrix-Junior<br>* Vaccines administrated according to product monographs' recommendations<br>|
| Experimental: Infanrix-hexa+Twinrix<br>Children vaccinated at the age of 2 and 18 months with a standard dose of Infanrix-hexa and a standard dose of Infanrix-Junior, respectively | Biological: Infanrix-hexa, Twinrix-Junior<br>* Vaccines administrated according to product monographs' recommendations<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Immunogenicity | The proportion of children with an anti-HBs titer ≥10mIU/ml | 1 month post last dose of vaccine | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Immune memory | Immune response to a booster dose | 36 months post last primary vaccine dose | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Vaccination, Two doses, Infants