Hepatitis A, Hepatitis B
Conditions
Keywords
Hepatitis A and hepatitis B
Brief summary
This study will evaluate the persistence of the immune response to HAV (hepatitis A virus) antigens and HBs (hepatitis B surface) antigens in healthy adults previously vaccinated with Twinrix Adult in the primary study, HAB-032 (208127/022). The subjects will be invited for blood sampling 16, 17, 18, 19 and 20 years after the primary vaccination to evaluate the antibody persistence. For subjects in whom low circulating antibodies are detected, the presence of immune memory against hepatitis A & B antigens will be investigated by the administration of a challenge dose of the appropriate vaccine (Havrix and/or Engerix-B) at the next planned visit. No new subjects will be recruited during this study.
Interventions
PROCEDUREBlood sampling
Blood sampling at Year 16, 17, 18, 19 and 20 and at the time of challenge dose administration and 14 days and one month after challenge dose administration (if challenge dose needed).
BIOLOGICALEngerix-B
Engerix-B will be administered to subjects who are not seroprotected against hepatitis B.
BIOLOGICALHavrix
Havrix will be administered to subjects who are seronegative for anti-HAV antibodies.
Sponsors
GlaxoSmithKline
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Healthy volunteers
Yes
Inclusion criteria
All subjects must satisfy the following criteria at entry into each of the long-term follow-up visits: * 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 primary vaccination course in the primary study 208127/022. * Written informed consent obtained from the subject. All subjects must satisfy the following criteria at entry into the challenge dose phase: * Subjects who the investigator believes that they can and will comply with the requirements of the protocol. * A male or female who received the complete primary vaccination course in the primary study 208127/022. * Written informed consent obtained from the subject. * Subjects who participated in the LTFU phase of the 208127/022 study and for whom the antibody concentrations were below the cut-off at the last available follow-up time-point. * Female subjects of non-childbearing potential may be enrolled in the study. * Female subjects of childbearing potential may be enrolled in the study, if the subject: * has practiced adequate contraception for 30 days prior to vaccination, and * has a negative pregnancy test on the day of vaccination, and * has agreed to continue adequate contraception for two months after the administration of the challenge dose.
Exclusion criteria
The following criteria should be checked before entry into each of the long-term follow-up visits. If any exclusion criterion applies, the subject must not be included in the study: * Use of any investigational or non-registered product within 30 days prior to blood sampling. * Administration of a hepatitis A, hepatitis B or combined hepatitis A and B vaccine outside the study procedures, since the primary study 208127/022. * History of hepatitis A or hepatitis B infection since the primary study 208127/022. * Administration of hepatitis A or hepatitis B immunoglobulins and/or any blood products within three months prior to blood sampling. The following criteria should be checked before the challenge dose is administered. If any apply, the subject must not be included in the challenge dose phase: * Use of any investigational or non-registered product within 30 days prior to study start or planned use during the study. * Administration of a hepatitis A, hepatitis B or combined hepatitis A and B vaccine between the last LTFU visit and the challenge dose visit. * History of hepatitis A or hepatitis B infection between the last LTFU visit and the challenge dose visit. * History of anaphylactic reactions following the administration of vaccines. * History of any reaction or hypersensitivity likely to be exacerbated by any component of the vaccines. * Acute disease and/or fever at the time of enrolment. * Pregnant or lactating female. * Female planning to become pregnant or planning to discontinue contraceptive precautions.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | At Years 16, 17, 18, 19 and 20. | Seropositivity for anti-HAV antibodies is defined as antibody concentrations \>= 15 milliinternational units per milliliter (mIU/mL). Seropositivity for anti-HBs antibodies is defined as antibody concentrations \>= 6.2 mIU/mL. |
| Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | At Years 16, 17, 18, 19 and 20. | Concentrations were expressed as GMCs in mIU/mL. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Subjects With Anamnestic Response to the Challenge Dose of Engerix-B | 30 days after the challenge dose of Engerix-B. | At Year 16 only 1 subject was eligible for the challenge dose of Engerix-B. Anti-HBs anamnestic response to the challenge dose was defined as: * Anti-HBs antibody concentrations \>= 10 mIU/mL at one month post-challenge dose in subjects seronegative at the pre-challenge time point. * At least a 4-fold increase in anti-HBs antibody concentrations, at one month post-challenge dose in subjects seropositive at the pre-challenge time point. |
| Number of Subjects With Anamnestic Response to the Challenge Dose of Havrix | 30 days after the challenge dose of Havrix. | Anti-HAV anamnestic response to the challenge dose was defined as: * Anti-HAV antibody concentrations ≥ 15 mIU/mL at one month post-challenge dose, in subjects seronegative at the pre-challenge time point. * At least a 2-fold increase in anti-HAV antibody concentrations one month after the challenge dose, in subjects having anti-HAV antibody concentrations ≥ 100 mIU/mL at the pre-challenge time point. * Or at least a 4-fold increase in anti-HAV antibody concentrations one month after the challenge dose, in seropositive subjects having anti-HAV antibody concentrations \< 100 mIU/mL at the pre-challenge time-point. |
| Anti-HBs Concentrations After the Challenge Dose of Engerix-B | Before, 14 days and one month (30 days) after the challenge dose of Engerix-B. | Concentration was given in mIU/mL. Only 1 subject was eligible for the challenge dose of Engerix-B at the Year 16 time point. Therefore the values for this subject are given without a measure of dispersion. |
| Number of Subjects With Serious Adverse Events (SAEs) | During the 31-day (Days 0-30) follow-up period after the Engerix-B challenge dose. | Only 1 subject received a challenge dose at Year 16 of Engerix-B. An SAE is any untoward medical occurrence that: results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect in the offspring of a study subject, or may evolve into one of the outcomes listed above. |
| Number of Subjects Reporting SAEs Related to Study Participation or a Concurrent GSK Medication | Up to Year 20. | An SAE is any untoward medical occurrence that: results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect in the offspring of a study subject, or may evolve into one of the outcomes listed above. |
| Number of Subjects Reporting Unsolicited Adverse Events (AEs) | 31 days (Days 0-30) after the challenge dose of Engerix-B and Havrix. | At Year 16, 1 subject was administered a challenge dose of Engerix-B and at Y18 and Y20, 2 subjects were administered a challenge dose of Havrix. An AE is any untoward medical occurrence in a clinical investigation subject, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. |
| Anti-HAV Concentrations After the Challenge Dose of Havrix | Before, 14 days and one month (30 days) after the challenge dose of Havrix. | Concentration was given in mIU/mL. Only 2 subjects were eligible for the challenge dose of Havrix, one at Year 18 and another at Year 20 time point. Therefore the values for these subject are given without a measure of dispersion. |
Countries
Belgium
Participant flow
Pre-assignment details
1 subject who was not able to come at Year (Y) 16 entered the study at Y17. At Y16, 1 subject was administered a challenge dose of Engerix-B vaccine and at Y18 and Y20, 2 subjects were administered a challenge dose of Havrix vaccine. None of the subjects received a challenge dose at Y17 and Y19.
Participants by arm
| Arm | Count |
|---|---|
| Twinrix Group Subjects who received 3 doses of Twinrix (lot A, B or C) in the primary study.
As lot to lot consistency was assessed during the primary study, the 3 groups (lot A, B or C) were pooled into the Twinrix Group for data analyses during the first long-term follow-up NCT00289718 and this long-term follow-up.
A challenge dose of the Havrix or Engerix-B vaccines can be administered in this study based on serology results at each time point. | 49 |
| Total | 49 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| Year 20 | Others | 1 |
Baseline characteristics
| Characteristic | Twinrix Group |
|---|---|
| Age, Continuous | 41.7 Years STANDARD_DEVIATION 5.9 |
| Sex: Female, Male Female | 36 Participants |
| Sex: Female, Male Male | 9 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | 0 / 49 |
| other Total, other adverse events | 1 / 3 |
| serious Total, serious adverse events | 0 / 49 |
Outcome results
Primary
Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs)
Concentrations were expressed as GMCs in mIU/mL.
Time frame: At Years 16, 17, 18, 19 and 20.
Population: The analysis was performed on the long-term according-to-protocol (LT ATP) cohort for immunogenicity which included subjects who returned at a particular blood sampling time point, who were included in the ATP analysis for the primary study and who did not receive hepatitis A or B vaccination that was not specified in the protocol.
| Arm | Measure | Group | Value (GEOMETRIC_MEAN) |
|---|---|---|---|
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HAV [at Year 16] (N=28) | 262.5 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HAV [at Year 20] (N=25) | 229.3 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HBs [at Year 16] (N=28) | 79.9 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HAV [at Year 17] (N=27) | 369.4 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HBs [at Year 17] (N=27) | 71.7 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HAV [at Year 18] (N=25) | 237.7 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HBs [at Year 18] (N=25) | 61.3 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HAV [at Year 19] (N=25) | 234.3 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HBs [at Year 19] (N=25) | 59.7 mIU/mL |
| Twinrix Group | Anti-HAV and Anti-HBs Geometric Mean Concentrations (GMCs) | anti-HBs [at Year 20] (N=25) | 57.7 mIU/mL |
Primary
Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL)
Seropositivity for anti-HAV antibodies is defined as antibody concentrations \>= 15 milliinternational units per milliliter (mIU/mL). Seropositivity for anti-HBs antibodies is defined as antibody concentrations \>= 6.2 mIU/mL.
Time frame: At Years 16, 17, 18, 19 and 20.
Population: The analysis was performed on the long-term according-to-protocol (LT ATP) cohort for immunogenicity which included subjects who returned at a particular blood sampling time point, who were included in the ATP analysis for the primary study and who did not receive hepatitis A or B vaccination that was not specified in the protocol.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HAV >= 15 mIU/mL [at Year 16] (N=28) | 28 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 6.2 mIU/mL [at Year 17] (N=27) | 25 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 6.2 mIU/mL [at Year 18] (N=25) | 23 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 10 mIU/mL [at Year 18] (N=25) | 23 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 6.2 mIU/mL [at Year 19] (N=25) | 23 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 10 mIU/mL [at Year 19] (N=25) | 23 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HAV >= 15 mIU/mL [at Year 20] (N=25) | 24 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 10 mIU/mL [at Year 20] (N=25) | 23 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 6.2 mIU/mL [at Year 16] (N=28) | 27 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 10 mIU/mL [at Year 16] (N=28) | 27 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HAV >= 15 mIU/mL [at Year 17] (N=27) | 26 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 10 mIU/mL [at Year 17] (N=27) | 25 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HAV >= 15 mIU/mL [at Year 18] (N=25) | 25 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HAV >= 15 mIU/mL [at Year 19] (N=25) | 24 Subjects |
| Twinrix Group | Number of Subjects Seropositive for Anti-hepatitis A Virus Antibodies (Anti-HAV) and Anti-hepatitis B Surface Antigen (Anti-HBs) Antibodies and With Anti-HBs Antibody Concentrations >= 10 Milliinternational Units Per Milliliter (mIU/mL) | anti-HBs >= 6.2 mIU/mL [at Year 20] (N=25) | 23 Subjects |
Secondary
Anti-HAV Concentrations After the Challenge Dose of Havrix
Concentration was given in mIU/mL. Only 2 subjects were eligible for the challenge dose of Havrix, one at Year 18 and another at Year 20 time point. Therefore the values for these subject are given without a measure of dispersion.
Time frame: Before, 14 days and one month (30 days) after the challenge dose of Havrix.
Population: The analysis was performed on the long-term according-to-protocol (LT ATP) cohort for immunogenicity which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Havrix vaccine because their anti-HAV antibody concentrations were \< 15 mIU/mL.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Twinrix Group | Anti-HAV Concentrations After the Challenge Dose of Havrix | 1 month (Day 30) after challenge dose at Year 18 | 3389 mIU/mL |
| Twinrix Group | Anti-HAV Concentrations After the Challenge Dose of Havrix | before challenge dose at Year 20 | 19 mIU/mL |
| Twinrix Group | Anti-HAV Concentrations After the Challenge Dose of Havrix | 14 days after challenge dose at Year 20 | 1096 mIU/mL |
| Twinrix Group | Anti-HAV Concentrations After the Challenge Dose of Havrix | before challenge dose at Year 18 | 25 mIU/mL |
| Twinrix Group | Anti-HAV Concentrations After the Challenge Dose of Havrix | 14 days after challenge dose at Year 18 | 3421 mIU/mL |
| Twinrix Group | Anti-HAV Concentrations After the Challenge Dose of Havrix | 1 month (Day 30) after challenge dose at Year 20 | 1060 mIU/mL |
Secondary
Anti-HBs Concentrations After the Challenge Dose of Engerix-B
Concentration was given in mIU/mL. Only 1 subject was eligible for the challenge dose of Engerix-B at the Year 16 time point. Therefore the values for this subject are given without a measure of dispersion.
Time frame: Before, 14 days and one month (30 days) after the challenge dose of Engerix-B.
Population: The analysis was performed on the long-term according-to-protocol (LT ATP) cohort for immunogenicity which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Engerix-B vaccine because their anti-HBs antibody concentrations were \< 10 mIU/mL.
| Arm | Measure | Group | Value (NUMBER) |
|---|---|---|---|
| Twinrix Group | Anti-HBs Concentrations After the Challenge Dose of Engerix-B | before challenge dose at Year 16 | 7.86 mIU/mL |
| Twinrix Group | Anti-HBs Concentrations After the Challenge Dose of Engerix-B | 14 days after challenge dose at Year 16 | 50640.0 mIU/mL |
| Twinrix Group | Anti-HBs Concentrations After the Challenge Dose of Engerix-B | 1 month (Day 30) after challenge dose at Year 16 | 31442.0 mIU/mL |
Secondary
Number of Subjects Reporting SAEs Related to Study Participation or a Concurrent GSK Medication
An SAE is any untoward medical occurrence that: results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect in the offspring of a study subject, or may evolve into one of the outcomes listed above.
Time frame: Up to Year 20.
Population: The LT Total cohort included all subjects who returned at each annual time point and who belonged to the Total cohort in the primary study.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Twinrix Group | Number of Subjects Reporting SAEs Related to Study Participation or a Concurrent GSK Medication | 0 Subjects |
Secondary
Number of Subjects Reporting Unsolicited Adverse Events (AEs)
At Year 16, 1 subject was administered a challenge dose of Engerix-B and at Y18 and Y20, 2 subjects were administered a challenge dose of Havrix. An AE is any untoward medical occurrence in a clinical investigation subject, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product.
Time frame: 31 days (Days 0-30) after the challenge dose of Engerix-B and Havrix.
Population: The analysis was performed on the long-term total cohort which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Engerix-B vaccine or Havrix.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Twinrix Group | Number of Subjects Reporting Unsolicited Adverse Events (AEs) | 1 Subjects |
Secondary
Number of Subjects With Anamnestic Response to the Challenge Dose of Engerix-B
At Year 16 only 1 subject was eligible for the challenge dose of Engerix-B. Anti-HBs anamnestic response to the challenge dose was defined as: * Anti-HBs antibody concentrations \>= 10 mIU/mL at one month post-challenge dose in subjects seronegative at the pre-challenge time point. * At least a 4-fold increase in anti-HBs antibody concentrations, at one month post-challenge dose in subjects seropositive at the pre-challenge time point.
Time frame: 30 days after the challenge dose of Engerix-B.
Population: The analysis was performed on the long-term according-to-protocol (LT ATP) cohort for immunogenicity which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Engerix-B vaccine because their anti-HBs antibody concentrations were \< 10 mIU/mL.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Twinrix Group | Number of Subjects With Anamnestic Response to the Challenge Dose of Engerix-B | 1 Subjects |
Secondary
Number of Subjects With Anamnestic Response to the Challenge Dose of Havrix
Anti-HAV anamnestic response to the challenge dose was defined as: * Anti-HAV antibody concentrations ≥ 15 mIU/mL at one month post-challenge dose, in subjects seronegative at the pre-challenge time point. * At least a 2-fold increase in anti-HAV antibody concentrations one month after the challenge dose, in subjects having anti-HAV antibody concentrations ≥ 100 mIU/mL at the pre-challenge time point. * Or at least a 4-fold increase in anti-HAV antibody concentrations one month after the challenge dose, in seropositive subjects having anti-HAV antibody concentrations \< 100 mIU/mL at the pre-challenge time-point.
Time frame: 30 days after the challenge dose of Havrix.
Population: The analysis was performed on the long-term according-to-protocol (LT ATP) cohort for immunogenicity which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Havrix vaccine because their anti-HAV antibody concentrations were \< 15 mIU/mL.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Twinrix Group | Number of Subjects With Anamnestic Response to the Challenge Dose of Havrix | 2 subjects |
Secondary
Number of Subjects With Serious Adverse Events (SAEs)
Only 1 subject received a challenge dose at Year 16 of Engerix-B. An SAE is any untoward medical occurrence that: results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, is a congenital anomaly/birth defect in the offspring of a study subject, or may evolve into one of the outcomes listed above.
Time frame: During the 31-day (Days 0-30) follow-up period after the Engerix-B challenge dose.
Population: The analysis was performed on the long-term total cohort which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Engerix-B vaccine because their anti-HBs antibody concentrations were \< 10 mIU/mL.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Twinrix Group | Number of Subjects With Serious Adverse Events (SAEs) | 0 Subjects |
Secondary
Number of Subjects With Serious Adverse Events (SAEs)
One subject received a challenge dose of Havrix at Year 18 and another at Year 20. Serious adverse events (SAEs) assessed include medical occurrences that result in death, are life threatening, require hospitalization or prolongation of hospitalization or result in disability/incapacity.
Time frame: During the 31-day (Days 0-30) follow-up period after the Havrix challenge dose.
Population: The analysis was performed on the long-term total cohort which included subjects who returned at the blood sampling time point for whom results were available and who received a challenge dose of Havrix vaccine because their anti-HAV antibody concentrations were \< 15 mIU/mL.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Twinrix Group | Number of Subjects With Serious Adverse Events (SAEs) | 0 subjects |