Hepatitis B Challenge Dose in Adults (V232-059-10)

Study Overview
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Brief Summary
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The purpose of this trial is to describe the Seroprotection Rate (SPR) at least 2 years following completion of a primary series with a hepatitis B vaccine (Base Study V232-059, NCT00440531) and 1 month following a challenge dose with a Modified Process Hepatitis B vaccine.

Official Title
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A Study to Estimate the Immune Response Following a Challenge Dose in Adults (≥50 Years Old) Vaccinated With a Primary Series of an Hepatitis B Vaccine

Conditions
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Hepatitis B

Intervention / Treatment
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* Biological: Modified Process Hepatitis B Vaccine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: In general good health based on a medical history. Received 3 doses of an Hepatitis B vaccine in Base Study V232-059, NCT00440531 at least 2 years prior to enrollment in this study. Exclusion Criteria: Known history of previous Hepatitis B infection. History of vaccination with any Hepatitis B vaccine within the last 2 years. History of febrile illness. Known or suspected hypersensitivity to any component of HBVaxPro. Receipt of medication / vaccine that may interfere with study assessments. Known or suspected immune impairment. Pregnant women and nursing mothers.

Ages Eligible for Study
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Minimum Age: 50 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
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Modified Process Hepatitis B Vaccine in Base Study<br>Participants who received 3 doses of Modified Process Hepatitis B Vaccine in the Base Study were eligible to receive a single challenge dose of Modified Process Hepatitis B Vaccine on Day 1 of the Challenge Dose Study | Biological: Modified Process Hepatitis B Vaccine<br>* Modified Process Hepatitis B Vaccine given IM (intramuscular) as a single 1.0 mL (10 mcg) challenge dose on Day 1 of the Challenge Dose Study<br>* Other names: HBVaxPro;|
| Experimental: ENGERIX-B™ Vaccine in Base Study<br>Participants who received 3 doses of ENGERIX-B™ vaccine in the Base Study were eligible to receive a single challenge dose of Modified Process Hepatitis B Vaccine on Day 1 of the Challenge Dose Study | Biological: Modified Process Hepatitis B Vaccine<br>* Modified Process Hepatitis B Vaccine given IM (intramuscular) as a single 1.0 mL (10 mcg) challenge dose on Day 1 of the Challenge Dose Study<br>* Other names: HBVaxPro;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Seroresponders Before and After the Challenge Vaccination | A seroresponder was a participant with an anti-hepatitis B surface antibody titer >=10 milli Merck U/mL. The percentage of seroresponders was assessed before and after the challenge dose. | Predose (Day 1) and 1 month after challenge dose (Month 1) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Participants With One or More Adverse Experiences | An adverse experience is defined as any unfavorable and unintended change in the structure, function, or chemistry of the body temporally associated with the use of the sponsor's product, whether or not considered related to the use of the product. Any worsening of a preexisting condition which is temporally associated with the use of the sponsor's product, is also an adverse experience. The percentage of participants with one or more adverse experiences was assessed. | Up to Day 15 after challenge dose | 
| Percentage of Participants Who Discontinued the Study Due to an Adverse Experience | The percentage of participants who discontinued the study due to an adverse experience was assessed. | Up to Month 7 | 
| Percentage of Participants With One or More Injection-site Adverse Experiences | The percentage of participants with one or more injection-site adverse experiences was assessed. | Up to Day 15 after challenge dose | 
| Percentage of Participants With One or More Systemic Adverse Experiences | The percentage of participants with one or more systemic adverse experiences was assessed. | Up to Day 15 after challenge dose | 
| Percentage of Participants With One or More Serious Adverse Experiences | A serious adverse experience is an adverse experience that results in death, is life threatening, results in persistent or significant disability or incapacity, results in or prolongs a hospitalization, is a congenital anomaly or birth defect, is a cancer, or may jeopardize the participant and may require medical or surgical intervention. The percentage of participants with one or more serious adverse experiences was assessed. | Up to Month 1 after challenge dose |