Challenge Dose of Hepatitis B Vaccine in Subjects Who Previously Received Engerix™-B Vaccine

Administration of a Challenge Dose of Hepatitis B Vaccine in Subjects Who Previously Received Engerix™-B Vaccine.

To evaluate the response to an additional dose (challenge dose) of hepatitis B vaccine, when given to subjects who had received primary vaccination of Engerix™-B vaccine approximately 72-78 months ago.

This protocol posting deals with objectives & outcome measures of the challenge phase. The Protocol Posting has been updated in order to comply with the FDA Amendment Act, Sep 2007.

Inclusion Criteria:

• Subjects who the investigator believes that they can and will comply with the requirements of the protocol.
• A male or female who had received complete primary vaccination course of hepatitis B vaccine in the primary study
• Written informed consent obtained from the subject and/or parent/guardian of the subject.
• Healthy subjects as established by medical history and clinical examination before entering into the study.
• If the subject is female, she must be of non-childbearing potential or if she is of childbearing potential, she must practice adequate contraception for 30 days prior to vaccination, have a negative pregnancy test and continue such precautions for 2 months after the hepatitis B challenge dose.

Exclusion Criteria:

• Use of any investigational/non-registered drug or vaccine other than the study vaccine within 30 days preceding the hepatitis B vaccine challenge dose or planned use during the study period.
• Chronic administration (more than 14 days) of immunosuppressants other immune-modifying drugs within six months prior to the hepatitis B vaccine challenge dose.
• Planned administration/ administration of a vaccine not foreseen by the study protocol during the period starting from 30 days before the hepatitis B vaccine challenge dose and ending 30 days after.
• Subjects who received an additional dose of hepatitis B vaccine outside the context of the study between the primary vaccination course and the hepatitis B challenge vaccination visit.
• Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product.
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccine.
• Any confirmed or suspected immunosuppressive or immunodeficient condition, based on medical history and physical examination.
• Acute disease at the time of enrolment.
• Acute or chronic, clinically significant hepatic or renal functional abnormality, as determined by physical examination or laboratory screening tests.
• Administration of immunoglobulins and/or any blood products within the three months preceding the hepatitis B vaccine challenge dose or planned administration during the study period (one month).
• Pregnant or lactating female.
• Female planning to become pregnant or planning to discontinue contraceptive precautions.