The long-term persistence of hepatitis B surface antibodies (anti-HBs) following hepatitis B vaccination in adults was unknown. The purpose of this study was to determine the immunogenicity and persistence of antibodies 8 years after hepatitis B immunization with various vaccination schedules in adults who tested negative for hepatitis B surface antigen (HBsAg), anti-HBs, and hepatitis B core antibody (anti-HBc). A total of 771 participants were recruited who received the full vaccination course (three doses) as well as a blood sample taken one month after the first vaccination. 529 were excluded due to missing anti-HBs data 8 years after the first vaccination. Vaccinations were administered at 0–1–3, 0–1–6, and 0–1–12 month intervals, with 104, 45, and 93 participants included, respectively. The positive seroprotection rate was 85.9% one month after the third vaccination and 58.3% eight years later, with the geometric mean titer (GMT) of anti-HBs being 158.49 mIU/mL after one month and 15.14 mIU/mL after eight years, respectively. 

The positive seroprotection rate and GMT of the 0–1–3 month vaccination schedule did not differ from the standard 0–1–6 month vaccination schedule. The 0–1–3 month vaccination schedule had a better long-term immune effect than the 0–1–12 month vaccination schedule. There was no correlation between the GMT of anti-HBs 1 month and 8 years later.

Reference: https://www.tandfonline.com/doi/full/10.1080/21645515.2019.1666612