Immunogenicity and safety of 4 vs. 3 standard doses of HBV vaccination in HIV-infected adults with isolated anti-HBc antibody.

BACKGROUND: Presence of isolated anti-HBc antibody is common in HIV-infected patients in endemic areas and could be caused by prior HBV infection with loss of anti-HBs antibody. The role of vaccination in these patients remains controversial and is based largely on limited and low quality data. We, therefore, conducted this study to determine immunogenicity and safety of 4 vs. 3 standard doses of HBV vaccination in HIV-infected adults with isolated anti-HBc antibody. METHODS: An open-label, randomized controlled trial was conducted among HIV-infected patients visiting HIV clinic of the Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand between July and September 2017. Inclusion criteria included ≥ 18 years of age, currently on a stable antiretroviral regimen, CD4+ cell count ≥ 200 cells/mm3, plasma HIV-1 RNA < 20 copies/mL, and isolated anti-HBc antibody. The participants were randomized to receive either 3 standard doses (20 µg at month 0, 1, 6) or 4 standard-doses (20 µg at month 0, 1, 2, 6) of IM HBV vaccination, and were evaluated for anamnestic response at week 4 and vaccine response at week 28. RESULTS: Of the 97 patients screened, 54 (32 male, mean age of 46 years) were enrolled and 27 were allocated to each of the vaccination groups. Anamnestic response occurred in 25.9% vs. 33.3% in 3-dose group vs. 4-dose group, respectively (p = 0.551). The vaccine response rates at week 28 were 85.2% in 3-dose group vs. 88.9% in 4-dose group (p = 1.000); geometric mean titer of anti-HBs antibody at week 28 was 63.8 and 209.8 mIU/mL in 3-dose group and 4-dose group, respectively (p = 0.030). No adverse events were reported. CONCLUSIONS: An anamnestic response occurred in one-third of Thai HIV-infected patients with isolated anti-HBc antibody who received one dose of HBV vaccination; however, the majority were still unprotected. The use of either 3 or 4 standard-doses of vaccination was highly effective and should be recommended in all HIV-infected individuals with isolated anti-HBc antibody. Trial registration ClinicalTrials.gov; NCT03212911. Registered 11 July 2019, https://clinicaltrials.gov/ct2/show/NCT03212911.

Higher rate of long-term serologic response of four double doses vs. standard doses of hepatitis B vaccination in HIV-infected adults: 4-year follow-up of a randomised controlled trial.

BACKGROUND: We previously reported that four doses or four double doses of hepatitis B vaccination regimens could not significantly increase a response rate compared with standard doses. However, the antibody levels were higher in the four doses and four double doses groups. This study followed those patients for at least 3 years and aimed to evaluate the immunogenicity of the three vaccination regimens. METHODS: HIV-infected adults who had CD4+ cell counts > 200 cells/mm3, undetectable plasma HIV-1 RNA, and negative for all hepatitis B virus markers were randomly assigned to receive one of three recombinant vaccines (Hepavax-Gene® Berna, Korea) regimens: 20 µg IM at months 0, 1, and 6 (standard doses group, n = 44), 20 µg IM at months 0, 1, 2, 6 (four doses group, n = 44), or 40 µg IM at months 0, 1, 2, and 6 (four double doses group, n = 44) between February 2011 and May 4, 2012. Of 132 participants, 126 were evaluated from August 2015 to January 2016; 42 in the standard doses, 43 in the four doses, and 41 in the four double doses groups. RESULTS: At a median duration of 49.7 months (range 46.7-53.7) after completion of the primary vaccination schedule, the percentages of responders with anti-HBs ≥ 10 mIU/mL were 57.1% (95% CI 41.5-72.8%) in the standard doses group; 76.7% (95% CI 63.6-89.9%) in the four doses group (P = 0.067 vs. the standard doses group); and 80.5% (95% CI 67.8-93.2%) in the four double doses group (P = 0.033 vs. the standard doses group). Factors associated with a responder were the vaccination schedule (either four doses or four double doses groups) and a younger age. CONCLUSIONS: Despite the highly effectiveness of the standard hepatitis B vaccination regimen at 6 months after completion, the long-term immunogenicity was lower than the four double doses regimen among HIV-infected adults with CD4+ cell counts > 200 cells/mm3 and undetectable plasma HIV-1 RNA. The standard vaccination regimen may not be the best strategy to provide long-term immune response against hepatitis B virus among HIV-infected individuals. Trial registration NCT1289106, NCT02713620.

Sensitivity and specificity of using CD4+ measurement and clinical evaluation to determine antiretroviral treatment failure in Thailand.

OBJECTIVE: We conducted a study to evaluate the sensitivity and specificity of using CD4+ measurement and clinical evaluation to detect antiretroviral treatment failure in HIV-infected patients who had received their first regimen of highly active antiretroviral therapy (HAART). The secondary objective was to determine the prevalence and risk factors of virological failure. METHODS: A retrospective cohort study was conducted at Chiang Mai University Hospital, Thailand. Univariate analysis was performed to compare risk ratios between patients with and without virological failure. Sensitivity and specificity of the immunological and/or clinical criteria in comparison with virological criteria were calculated using 2 by 2 tables. RESULTS: From January 2003 to December 2005, 327 HIV-infected patients were enrolled. The median follow-up period was 19 months (range 6-42 months). Virological failure was detected in 9.2% of patients. Patients with a previous history of opportunistic infection had a greater risk for developing virological failure (OR=2.66, 95% CI=1.1-6.4). Using the combined immunological and clinical criteria to detect antiretroviral treatment failure, the sensitivity was 20.0% and the specificity was 85.9%. CONCLUSIONS: Our study, which was limited by small numbers, was not able to demonstrate that immunological or clinical criteria can adequately replace virological criteria for the determination of treatment failure.