Long-term Immune Persistence of GSK Biologicals' Combined Hepatitis A & B Vaccine Injected According to a 0,1,6 Mth Schedule in Healthy Adults

• Number of Subjects With Anti-hepatitis A (Anti-HAV) Antibody Concentrations Equal to or Above Cut-off Value [ Time Frame: Years 11, 12, 13, 14 and 15 ] [ Designated as safety issue: No ]
  Cut-off value was defined as 15 milli-international units per milliliter (mIU/mL). This was considered as seropositivity.
  
  
• Number of Subjects With Anti-hepatitis B Surface Antigen (Anti-HBs) Antibody Concentrations Equal to or Above Cut-off Values [ Time Frame: Years 11, 12, 13, 14 and 15 ] [ Designated as safety issue: No ]
  Cut-off values were defined 3.3 mIU/mL, which was also considered as seropositivity, and 10 mIU/mL.
  
  
• Anti-HAV and Anti-HBs Antibody Concentrations [ Time Frame: Years 11, 12, 13, 14 and 15 ] [ Designated as safety issue: No ]

  Concentrations are expressed as geometric mean concentrations (GMCs) in mIU/mL.

  The laboratory assay was changed at Year 13 for anti-HBs GMCs.

  
  
• Anti-HBs Antibody Concentrations [ Time Frame: at Year 11, pre-additional vaccine, after additional dose of Engerix ] [ Designated as safety issue: No ]

  Subjects who lost seroprotective concentrations for anti-HBs (< 10 mIU/mL) at any of the LT follow-up timepoints received an additional dose of Engerix after year 15.

  Two subjects were eligible for this after Year 11.

  3.29 in the table means a concentration of < 3.3 mIU/mL.

  As the concentration was calculated per subject no mean concentration was calculated and also no measure of dispersion.

  
  
• Number of Subjects, Receiving an Additional Vaccination of Engerix, With an Anamnestic Response [ Time Frame: 30 days post additional dose of Engerix ] [ Designated as safety issue: No ]

  Anamnestic response was assessed in subjects receiving an additional vaccine dose of Engerix. Two subjects were found eligible at Year 11 for this additional vaccine dose.

  Anamnestic response was defined as:

  • post-additional vaccination anti-HBs concentration >= 10 mIU/mL in subject seronegative before additional dose.
  • 4-fold increase post-additional dose compared to pre-additional vaccine time point.
  
  
• Number of Subjects With Solicited Local and General Symptoms Assessed [ Time Frame: During the 4-day follow-up period after additional vaccination with Engerix ] [ Designated as safety issue: No ]
  Solicited local symptoms were pain, redness and swelling. Solicited general symptoms were fatigue, fever, gastrointestinal, headache.
  
  
• Number of Subjects With Unsolicited Symptoms [ Time Frame: During the 30-day follow-up period after additional Engerix vaccination ] [ Designated as safety issue: No ]
  Unsolicited AE covers any AE reported in addition to those solicited during the clinical study and any solicited symptom with onset outside the specified period of follow-up for solicited symptoms.
  
  
• Number of Subjects With Serious Adverse Events (SAEs) [ Time Frame: During the 30-day follow-up period after additional Engerix vaccination ] [ Designated as safety issue: No ]
  SAEs assessed include medical occurrences that result in death, are life threatening, require hospitalization or prolongation of hospitalization, result in disability/incapacity or are a congenital anomaly/birth defect in the offspring of a study subject
  
  
• Number of Subjects With Serious Adverse Events (SAEs) Determined by the Investigator to Have a Causal Relationship to Primary Vaccination or Due to Lack of Vaccine Efficacy [ Time Frame: up to Year 11, 12, 13, 14, 15 ] [ Designated as safety issue: No ]
  SAEs assessed include medical occurrences that result in death, are life threatening, require hospitalization or prolongation of hospitalization, result in disability/incapacity or are a congenital anomaly/birth defect in the offspring of a study subject.
  
  

This is a long-term follow-up study at Years 11, 12, 13, 14 and 15 after primary vaccination with GSK Biologicals' hepatitis A/hepatitis B vaccine (three-dose schedule with 3 different lots). To evaluate the long-term antibody persistence, volunteers will be bled at Years 11, 12, 13, 14 and 15 after the first vaccine dose of the primary vaccination course to determine their anti-HAV and anti-HBs antibody concentrations.

No additional subjects will be recruited in the course of this extension study. If a subject has become seronegative for anti-HAV antibodies or lost anti-HBs seroprotection concentrations at the long-term blood sampling time point (i.e. Years 11, 12, 13, 14 or 15), he/ she will be offered an additional vaccine dose.