A Hepatitis B Vaccine Challenge Study After Previous Vaxelis® Vaccination (V419-013)

Study Overview
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Brief Summary
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The purpose of this study is to demonstrate the durability of protection against hepatitis B virus (HBV) infection approximately 8-9 years after vaccination with Vaxelis®. This is an estimation study, and no formal hypothesis testing was performed.

Official Title
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A Hepatitis B Vaccine Challenge Study to Demonstrate the Durability of Protection Against Hepatitis B Virus Infection in Healthy Children Vaccinated Approximately 9 Years Previously With a 2- or 3-Dose Infant Series and Toddler Dose of Vaxelis®

Conditions
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Hepatitis B

Intervention / Treatment
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* Biological: HBVAXPRO™


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Is healthy (based on a review of medical history and targeted physical examination) based on the clinical judgment of the investigator. Has participated in Protocol V419-007 and received a 3 + 1 Vaxelis® schedule or participated in Protocol V419-008 and received a 2 + 1 Vaxelis® schedule. The participant (or legally acceptable representative if applicable) provides written informed consent/assent for the study. Exclusion Criteria: Has a history of diagnosis (clinical, serological, or microbiological) of HBV infection. Has a known or suspected impairment of immunological function (e.g., human immunodeficiency virus (HIV), splenectomy). Has a known hypersensitivity to any component of the study vaccine. Has a known or suspected blood dyscrasias, leukemia, lymphomas of any type or other malignant neoplasms affecting the haematopoietic and lymphatic system. Has a bleeding disorder contraindicating intramuscular vaccinations. Has received any hepatitis B vaccine after participation in Protocol V419-007 or V419-008. Is or has an immediate family member (e.g., spouse, parent/legal guardian, sibling, or child) who is investigational site or Sponsor staff directly involved with this study.

Ages Eligible for Study
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Minimum Age: 8 Years
Maximum Age: 10 Years

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
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: HBVAXPRO™<br>Healthy children vaccinated approximately 8-9 years previously with a 2- or 3-dose infant series and toddler dose of Vaxelis® who will receive a single dose of Hepatitis B vaccine challenge (HBVAXPRO™). | Biological: HBVAXPRO™<br>* Single 0.5 mL intramuscular dose<br>* Other names: Hepatitis B virus (HBV) vaccine; V232;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With a Protective Hepatitis B Surface Antibody Level of ≥10 Milli International Units/mL (mIU/mL) at 30 Days Post-Challenge With HBVAXPRO™ | Participant serum samples were collected for analysis with an enhanced chemiluminescence (ECi) assay to determine the concentration of antibodies to hepatitis B surface antigen (HBsAg). Response rate was the percentage of participants with a protective hepatitis B surface antibody (anti-HBs) level of ≥ 10 mIU/mL at Day 30 post-challenge. | Day 30 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Geometric Mean Concentration of Antibodies to Hepatitis B Surface Antigen | Participant serum samples will be assessed with an ECi assay for anti-HBs geometric mean concentrations (GMCs) pre-challenge on Day 1 and 30 days post-challenge with HBVAXPRO™ in mIU/mL. | Day 1 and Day 30 |