immune response of healthy subjects who received neonatal vaccination course with engerix™-b vaccine.

Conditions: Hepatitis B

Summary: this study will evaluate the immune response of healthy subjects who received neonatal vaccination course with gsk biologicals' engerix™-b vaccine, approximately 20 years ago. the presence of immune memory against hepatitis b surface antigen (hbsag) in these subjects will be investigated by the administration of a challenge dose of hepatitis b vaccine and the comparison of their antibody concentration before and one month after vaccination. this protocol posting deals with objectives \& outcome measures of the booster phase. no new subjects will be recruited during this booster phase of the study.


Eligibility criteria:
inclusion criteria: * subjects who the investigator believes that they can and will comply with the requirements of the protocol should be enrolled in the study. * a male or female who received the complete neonatal primary vaccination course of engerix™-b in the 103860/273 primary study approximately 20 years earlier. * anti-hbs antibody concentrations less than the specified value at the last available follow-up time-point. * written informed consent obtained from 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 completion of the vaccination. exclusion criteria: * use of any investigational or non-registered product (drug or vaccine) other than the study vaccine within 30 days preceding the engerix™-b challenge dose, or planned use during the study period. * chronic administration (defined as more than 14 days) of immunosuppressant or other immune-modifying drugs within six months prior to challenge dose administration. * planned administration/ administration of a vaccine not foreseen by the study protocol starting from 30 days before the challenge dose and ending 30 days after. * administration of a hepatitis b vaccine outside the context of this study between the follow-up time-point at which anti-hbs antibody concentrations was less than the specified value and the current challenge dose study 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. * acute disease at the time of enrolment. * any confirmed or suspected immunosuppressive or immunodeficient condition, including human immunodeficiency virus (hiv) infection. * acute or chronic, clinically significant pulmonary, cardiovascular, 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 challenge dose visit or planned administration during the study period. * pregnant or lactating female. * female planning to become pregnant or planning to discontinue contraceptive precautions.

Keywords: engerix-b hepatitis b