Persistence of Hepatitis A Antibody in Healthy Adults ~32 Years Post Vaccination.

Launched by BEST HEALTHCARE INC. · Dec 14, 2023

Keywords

ClinConnect Summary

This clinical trial is studying how long the protection from a Hepatitis A vaccine lasts in healthy adults who were vaccinated about 32 years ago. Researchers want to find out if the antibodies that protect against Hepatitis A are still present and how the immune system responds if a booster dose of the vaccine is given to those who no longer have detectable antibodies. Participants will be asked to provide a blood sample to help answer these questions.

To be eligible for the study, participants need to have been part of a Hepatitis A study back in 1991 and must not have any detectable antibodies now. Individuals who have received any other types of Hepatitis A vaccines or have a history of Hepatitis A infection cannot participate. If someone qualifies and has no detectable antibodies, they will have the opportunity to receive an additional dose of the vaccine. This study is not yet recruiting participants but aims to gather important information about long-term immunity to Hepatitis A.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • Consent obtained
• • Participated in original hepatitis A study in 1991
• • No detectable hepatitis A antibody \~32 years after study start
• Exclusion Criteria:
• • Receipt of any dose of hepatitis A vaccine other than the hepatitis A vaccine used in the initial studies
• • History of hepatitis A
• • Receipt of blood transfusion or blood products, including immunoglobulins, within the past 6 months.
• • Receipt of any vaccine within the 14 days before receipt of the additional dose of hepatitis A vaccine or scheduled to receive any vaccine within 30 days after receipt of a booster dose of vaccine.