Description Module
The Description Module contains narrative descriptions of the clinical trial, including a brief summary and detailed description. These descriptions provide important information about the study's purpose, methodology, and key details in language accessible to both researchers and the general public.
Description Module path is as follows:
Study -> Protocol Section -> Description Module
Description Module
Ignite Creation Date:
2025-12-25 @ 12:11 AM
Ignite Modification Date:
2025-12-25 @ 12:11 AM
NCT ID:
NCT00169858
Brief Summary:
Hepatitis B immunization has been offered to all grade 4 students (age 9-10) in the province of Quebec, using Engerix-B at a dose of 10 mkg. The peak incidence of hepatitis B occurs between age 15 and 35; the proportion of vaccinated children who will still be protected at this age is currently unknown. This study is designed to determine:
* persistence of immunity until age 25
* persistence of immunological memory as demonstrated by an anamnestic response following a booster dose
* the effect of a booster dose on immunogenicity at either 5, 10 or 15 years after the primary vaccination course (at age (15, 20 or 25).
Detailed Description:
Three doses of Engerix-B vaccine (10 mkg) were administered according to 0, 1, 6 month schedule to 1126 9-10 year-old children.
The primary objective of the study is to evaluate the persistence of antibodies to Engerix-B in all subjects at age 25 and to compare the levels obtained in those given a booster injection at age 15 or 20 with those receiving no booster injection.
Secondary objectives
* To determine the antibody levels obtained following primary vaccination and the proportion of children who seroconvert
* To determine the antibody levels of one third of subjects at age 15, 5 years after primary vaccination (Group A)
* To determine the effect on antibody levels of a booster injection at age 15 years given to one third of the subjects (Group A)
* To determine the antibody levels of subjects in groups A and B at age 20, 5 years after booster (Group A), 10 years after primary vaccination (Group B)
* To determine the effect on antibody levels of a booster injection at age 20 years given to one third of the subjects (Group B)
* To determine the effect on antibody levels of a booster injection at age 25 years given to one third of the subjects (Group C)
* To determine the antibody levels of subjects in Group A and Group B one year after their 5 or 10 year booster
* To evaluate safety
Study:
NCT00169858
Study Brief:
Protocol Section:
NCT00169858