A follow-up study on the protective efficacy and anamnestic response of recombinant CHO hepatitis B vaccine 26 years after immunization

Vaccine. 2025 Oct 3:64:127743. doi: 10.1016/j.vaccine.2025.127743. Epub 2025 Sep 12.

Abstract

A 2024 cross-sectional survey in Zhengding County, Hebei, evaluated the 26-year protective efficacy of the Chinese hamster ovary (CHO) cell-derived hepatitis B vaccine (CHO-HepB) and 6.5-year anamnestic response to booster vaccination. Cohort I comprised 178 participants born 1997 and 1999 who had received the standard three-dose series at birth and no subsequent booster. Their mean interval since vaccination was 25.7 years. HBsAg, anti-HBc, and anti-HBs positivity rates were 0.56 % (95 % CI: 0-1.66 %), 1.12 % (95 % CI, 0-2.67 %) and 64.61 % (95 % CI, 57.88-71.34 %), respectively. Among 115 positive individuals, the geometric mean concentration (GMC) was 84.93 mIU/mL (95 % CI, 65.99-109.31). Against a historical local HBsAg prevalence of 11.3 %, the estimated vaccine protection rate was approximately 95.0 %. Serial surveys of the same cohort conducted in 2005, 2009, 2013, 2017, and 2024 revealed no significant increase in HBsAg or anti-HBc positivity over 7-26 years post-vaccination (both P > 0.05), whereas anti-HBs positivity declined significantly (P < 0.05). Cohort II included 97 individuals who received a booster in 2018. After 6.5 years, none were HBsAg or anti-HBc-negative; however, anti-HBs positivity fell from 87.6 % to 51.5 %, and GMCs declined accordingly. In conclusion, CHO-HepB confers durable protection for at least 26 years, with no new infections or carriers observed despite waning anti-HBs levels. Routine booster does may be unnecessary for the general population, yet targeted boosting could help sustain herd immunity and avert future outbreaks, particularly in high-risk populations. Continued emphasis on preventing mother-to-child transmission remains essential for hepatitis B control.

Keywords: Anamnestic response; Hepatitis B virus surface antibody (anti-HBs); Long-term protective efficacy; Recombinant CHO cell-derived hepatitis B vaccine.

MeSH terms

  • Adolescent
  • Adult
  • Animals
  • CHO Cells
  • Cricetulus
  • Cross-Sectional Studies
  • Female
  • Follow-Up Studies
  • Hepatitis B Antibodies / blood
  • Hepatitis B Antibodies / immunology
  • Hepatitis B Surface Antigens / blood
  • Hepatitis B Surface Antigens / immunology
  • Hepatitis B Vaccines* / administration & dosage
  • Hepatitis B Vaccines* / immunology
  • Hepatitis B* / immunology
  • Hepatitis B* / prevention & control
  • Humans
  • Immunization, Secondary
  • Immunologic Memory*
  • Male
  • Middle Aged
  • Vaccination
  • Vaccine Efficacy*
  • Vaccines, Synthetic / administration & dosage
  • Vaccines, Synthetic / immunology
  • Young Adult

Substances

  • Hepatitis B Vaccines
  • Hepatitis B Antibodies
  • Vaccines, Synthetic
  • Hepatitis B Surface Antigens