Journal Article

P173 Hepatitis B vaccine response in people living with HIV and with isolated anti-HBc serological profile: a retrospective study

Guarise, E, Nofri, M, Postma, P M, A Di Biagio, Taramasso, L, Cardaci, S, Massaro, E, Sticchi, L

2025

Overview

BackgroundGlobally, 8% to 10% of people living with HIV (PLWH) are also infected with chronic HBV. An isolated hepatitis B core antibody (IAHBc) profile, characterized by a positive anti-HBc with negative HBsAg and anti-HBs, is found in 14% to 44% of PLWH and in up to 31% of those coinfected with HIV and hepatitis C virus (HCV). This study aims to assess the antibody response (AR) after vaccination, defined by an HBsAb result of ≥10 mIU/mL, and the associated factors, in a selected group of PLWH with an IAHBc serological profile.Material and MethodsThis retrospective study analysed data from PLWH who attended the outpatient clinic at Policlinico San Martino Hospital, between 2016 and 2025. The focus was on individuals with an IAHBc profile who received at least one dose of HBV vaccine. Clinical data included CD4 counts before HBV vaccination and HCV coinfection status. CD4 counts were analysed both as continuous and dichotomized variables at 350 cells/μL according to literature (CD4 350: 0=≤350, 1=>350). Age was similarly analysed both continuously and dichotomized at the mean value.ResultsOf the 926 PLWH subjects attending the outpatient clinic, 24 were included in the analysis. HBV DNA testing was available and negative in 20 subjects (83.3%). The study population had a mean age of 62.25 (SD 4.9) and a predominance of males (83.3%). HCVAb were detected in 19 subjects, representing the 79.2%. HBVAb serology was assessed in two groups (figures 1 and 2): in the first group (8 subjects), it was assessed at least one month after the single recall dose; in the second group (14 subjects), after a full vaccination cycle (3 doses).In the first group, 50% achieved an AR, 25% did not achieved an AR and thus completed the full vaccination cycle, 25% were lost to follow-up. Among those who completed the cycle, none achieved an immunological response (IR). In the second group, 42.9% achieved an IR, 42.9% did not respond, and 12.5% were lost to follow-up. Of the 6 non-responders, 4 received a second complete vaccination cycle and 2 of them achieved an IR. Fisher’s exact test showed no significant association between age and protective antibody levels (p=0.266) after one cycle. However, a non-significant trend was observed, with 75% of participants above the mean age having protective titres, compared to 33.3% in participants below the mean age. Spearman’s correlation revealed no significant association between pre-vaccination CD4 counts and post-single recall dose antibody titres (rho=-0.1670, p=0.6823). The same analysis showed a strong association when considering the antibody titre after one complete cycle (rho = 0.55, p = 0.053).Abstract P173 Figure 1Correlation matrix between age, CD4 count pre vaccination and titre post single recall dose[Figure omitted. See PDF]Abstract P173 Figure 2Correlation matrix between age, CD4 count pre vaccination and titre post first vaccination cycle[Figure omitted. See PDF]ConclusionsThis study found variable antibody responses to HBV vaccination in PLWH with an IAHBc profile. Age and CD4 counts showed no significant impact, although a trend toward better responses in older individuals was noted. However larger samples are needed to better understand factors influencing vaccine efficacy.

• Publisher: BMJ Publishing Group LTD
• Subject: Age / Antibodies / Hepatitis B / Hepatitis C / HIV / Human immunodeficiency virus / Immunization / Outpatient care facilities / Serology / Vaccines