Evaluation of the immune response to hepatitis B vaccine in patients on biological therapy: results of the RIER cohort study

To evaluate the response to hepatitis B virus (HBV) vaccine in patients on biological therapy. Adults with autoimmune inflammatory diseases on biological therapy such as anti-TNFα, rituximab, tocilizumab, abatacept, or anakinra were included. Hepatitis B surface antibody (anti-HBs) was measured by ELISA before and after vaccination. Seroconversion was considered when an anti-HBs titer > 10 mIU/mL was achieved. The effect of treatment on the immunoprotective state was studied. The response was compared with that obtained in patients on synthetic disease modifying anti-rheumatic drugs (DMARDs) and healthy controls. A total of 187 patients on biologicals, 48 on synthetic DMARDs, and 49 on healthy controls were analyzed. More than 80% of patients on biologics responded to the vaccine but required more boosters and second vaccine series. Patients who achieved seroconversion were younger than those who did not (47.10 ± 12.99 vs. 53.18 ± 10.54 years, p = 0.012). Being on etanercept or golimumab was associated with seroconversion, while being on rituximab was not. Seroconversion was achieved in 93.75% of patients on synthetic DMARDs and 97.96% of healthy controls. The seroconversion rate in the biologics group was lower than in the synthetic DMARD group (p = 0.043) and tended to be lower than in the healthy group (p = 0.056). In patients on biological therapy, a high rate of HBV vaccine response can be achieved when a complete vaccination schedule is administered. Vaccination while not on biological agents reduces the requirement for boosters and revaccination.Key points:• Patients on biological therapy can achieve high rates of immune response to HBV vaccine when complete vaccination schedules are administered.• However, to achieve such a high seroconversion rate, more boosters and second vaccination series are required.• This supports the proposal already made to provide HBV vaccination to all patients with an autoimmune inflammatory disease after the diagnosis is made and not when the use of a biological treatment is under consideration.