Effectiveness of the Hepatitis B Vaccine Post-Hematopoietic Stem Cell Transplant

Based on current medical literature, the risk of hepatitis B reactivation is high after allogenic stem cell transplant and can be a major problem in the post-transplant population, leading to increased morbidity and mortality. Additionally, many people in the general population and transplant population do not achieve immunity against hepatitis B with the first vaccination series and may require repeat series.

Currently, it is unclear as to what percentage of post-transplant patients have a failed or delayed immunity against hepatitis B and how many vaccine series it may take to eventually achieve immunity. Previous data has eluded toward a seroconversion rate of 64% in children and adults after vaccination with 20% of patients losing immunity by 5-years post-vaccination. Additionally, the study found that 25% of patients did not achieve protective titers following one vaccination series and of those that went on to be revaccinated, 55% achieved seroconversion.

This is a single-center, retrospective analysis examining the effectiveness of the hepatitis B vaccine posthematopoietic stem cell transplant and the impact of factors that may affect seroconversion. Through this study, we hope to collect data on hepatitis B vaccination and recommend potential protocol revisions if trends are found. We hypothesize that hepatitis B immunity post-first vaccine series will occur in the majority of patients evaluated and that patients failing to respond to the first vaccine series, will respond to subsequent vaccination series.

The primary objective will be to assess the rate of achieved immunity for those patients that do not achieve immunity with the first vaccine series and require two or more vaccine series. Secondary and exploratory objectives will include the evaluation of the percentages of patients responding to vaccination on the 1st, 2nd, and 3rd attempt at the hepatitis B vaccination series, the rate of reactivation of hepatitis B, and the analysis of factors potentially impacting the response to vaccination.

• INCLUSION CRITERIA:

• Patient must have received at least one dose of the hepatitis B vaccine and been enrolled in the following NHLBI protocols: 99-H-0050, 10-H-0154, and 08-H-0046.
• Post-vaccination titers must be available for patients included in the study.

Exclusion criteria

• No post-vaccination titers available.