Size Matters! Anti-HBs Titer and HBV Reactivation During Anti-TNF Therapy

Area of Science:

• Hepatology
• Immunology
• Oncology

Background:

• Hepatitis B virus (HBV) reactivation is a concern in patients receiving anti-tumor necrosis factor (TNF) therapy.
• Previous studies suggested hepatitis B surface antibody (anti-HBs) protection, but lacked sufficient data on titer levels.
• This study aimed to clarify the correlation between anti-HBs titer and HBV reactivation severity.

Approach:

• Systematic review of studies on anti-TNF therapy in patients with resolved HBV infection (HBsAg negative, anti-HBc positive).
• Analyzed 48 reactivation cases from cohort studies, case reports, and case series.
• Correlated anti-HBs titers (negative, positive <100 IU/L, positive >100 IU/L) with reactivation outcomes.

Key Points:

• Hepatitis B surface antigen (HBsAg) sero-reversion occurred predominantly in patients with negative, low, or declining anti-HBs titers.
• A significant trend showed less clinically relevant reactivation with increasing baseline anti-HBs titers (p=0.022).
• Anti-HBs titers >100 IU/L demonstrated a protective effect against significant HBV reactivation.

Conclusions:

• Quantitative baseline anti-HBs titers are crucial before initiating anti-TNF therapy.
• Anti-HBs titers >100 IU/L are associated with protection against clinically relevant HBV reactivation.
• Vaccination to boost anti-HBs titers may be considered before and during anti-TNF therapy.