Hepatitis B Vaccination in People Living with HIV: Bridging the Immunological Gap

Hepatitis B virus (HBV) infection remains a major driver of liver-related morbidity and mortality among people living with HIV (PLWH), yet vaccine-induced protection is frequently suboptimal. HIV-associated immune dysfunction, including CD4⁺ T-cell depletion, altered antigen presentation, impaired T follicular helper cell support, and B-cell dysregulation, reduces seroprotection after standard recombinant HBV vaccines and may limit durability of antibody responses. Vaccine response is further influenced by HIV viral suppression, age, comorbidities, prior vaccine history, and baseline HBV serologic status, including isolated hepatitis B core antibody (anti-HBc) and occult HBV infection (OBI) considerations. Although antiretroviral therapy (ART) improves vaccine responsiveness, many PLWH fail to achieve protective hepatitis B surface antibody (anti-HBs) titers (≥10 mIU/mL) after conventional schedules, or experience antibody waning over time. Current guidelines recommend HBV vaccination for all susceptible PLWH with post-vaccination serologic testing and revaccination for nonresponders. Persistent implementation barriers, including incomplete series, vaccine hesitancy, stigma, and logistical constraints, continue to limit real-world impact. Emerging clinical trial data support CpG-adjuvanted HBV vaccines (HepB-CpG/Heplisav-B) and intensified dosing and schedules (double-dose or four-dose regimens) to improve seroprotection and generate higher peak anti-HBs titers, which may enhance durability. This review synthesizes guideline recommendations, immunologic mechanisms of hyporesponsiveness, predictors of vaccine response, and practical strategies to optimize HBV vaccination in PLWH.