An interventional study of recombinant hepatitis B vaccine in Hepatitis B, Vaccination; Infection and Preventable Disease, Vaccine, sponsored by National Taiwan University Hospital. Recruiting at 1 site in Taiwan. Open to participants aged 20 Years to 36 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-21.
Sponsored by National Taiwan University Hospital · Not applicable, Interventional, and Prevention
This prospective cohort study aims to provide the evidence-based clinical guide to help decide the revaccination doses of hepatitis B vaccine that the high-risk young adults without hepatitis B seroprotective antibodies (anti-HBs titer\<10 mIU/mL) need to take.
Purpose For young adults born after the neonatal hepatitis B immunization program, especially those who were 20-33 years old after 1987, additional hepatitis B vaccination may have the benefit of strengthening protection from acute hepatitis B infection among high-risk groups. However, how many doses are most appropriate for the protection of high-risk groups is still an issue to be resolved. This study aims to provide the evidence-based clinical guide to help decide the revaccination doses of hepatitis B vaccine that the high-risk young adults without hepatitis B seroprotective antibodies (anti-HBs titer\<10 mIU/mL) need to take.
Materials and Methods From August 2021 to July 2024, the investigator will invite young adults born in Taiwan over the age of 20 and born after 1987, who have received a full course of hepatitis B vaccine at least three doses at their infant period. Those who are all negative for hepatitis B surface antibodies (anti-HBs) and surface antigens (HBsAg) are enrolled to 4 groups according to the anti-HBs titer concentration (anti-HBs titer between 2.5-10 mIU/mL is a low concentration, anti-HB titer less than 2.5 mIU/mL is an extreme low concentration) with one or two doses of hepatitis B vaccine (Engerix-B) administered, respectively. Each group recruits 60 cases to reach a total of 240 participants. Each participant was followed for 12 months, and the anti-HBs titer concentration was measured in 0, 7-10 days, 28 days, 24- 28 weeks, and 48-52 weeks. The investigator will calculate the anti-HBs titer reaction rate and immune response after receiving hepatitis B vaccine(s) at each stage, and do further univariate and multivariate analysis.
Expected Results This prospective cohort study can help understand the difference in the anti-HBs titer response after 1 or 2 revaccination doses by the anti-HBs titer concentration as well as the two different types of hepatitis B vaccination in childhood It is expected to provide an important reference for the administration of hepatitis B vaccine in young adults of high-risk groups.
1,045 studies on the registry are indexed under Hepatitis B; 139 are open to participants now.
This study's planned enrollment of 240 is above the median of 147 across 756 interventional studies indexed under Hepatitis B.
Browse Hepatitis B studies →National Taiwan University Hospital is the lead sponsor of 2,615 studies on the registry; 576 are open to participants now.
Of its 11 completed or terminated interventional studies of FDA-regulated products, 2 (18%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
anti-HBs titer 2.5-10 mIU/mL with two doses of HB Vaccines at Day 0 and Day 28
Biological: recombinant hepatitis B vaccine
anti-HBs titer 2.5-10 mIU/mL with one dose of HB Vaccine at Day 0
Biological: recombinant hepatitis B vaccine
anti-HBs titer lower than 2.5 mIU/mL with two doses of HB Vaccines at Day 0 and Day 28
Biological: recombinant hepatitis B vaccine
anti-HBs titer lower than 2.5 mIU/mL with one dose of HB Vaccine at Day 0
Biological: recombinant hepatitis B vaccine
Hepatitis B vaccine (Engerix-B) will be administered to the eligible participants by 4 groups. Each case will be tracked for 12 months, at 0, 7-10 days, 28 days, 24-28 weeks, 48-52 weeks anti-HBs titer concentration and 4 follow-up questionnaires.
Also known as: Engerix-B
anti-HBs titer response rate at 7-10 days
the anti-HBs titer response rate after 1-2 doses of hepatitis B vaccine(s)
Time frame: 7-10 days
anti-HBs titer response rate at one month
the anti-HBs titer response rate after 1-2 doses of hepatitis B vaccine(s)
Time frame: 28 days
anti-HBs titer response rate at 6 months
the anti-HBs titer response rate after 1-2 doses of hepatitis B vaccine(s)
Time frame: 24-28 weeks
anti-HBs titer response rate at 12 months
the anti-HBs titer response rate after 1-2 doses of hepatitis B vaccine(s)
Time frame: 48-52 weeks
anti-HBs titer immune response change at 12 months
anti-HBs titer immune response change at 12 months after 1-2 doses of hepatitis B vaccine(s)
Time frame: 48-52 weeks
Plan to share: No
No publications or documents are linked to this record.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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