ABSTRACT
BACKGROUND: Antibody responses to standard regimens of hepatitis B (HBV) vaccination are lower in HIV-infected subjects and the best hepatitis B vaccine schedule in this population is not known. OBJECTIVE: To assess the immunogenicity and to evaluate predictors of serologic response of a modified regimen of a HBV recombinant vaccine in a cohort of HIV-infected subjects. METHODS: HIV-infected subjects received 4 doses (40 µg) of a recombinant HBV vaccine at 0, 1, 2 and 6 months. Demographic information as well as CD4 cell count and plasma viral load were assessed at baseline. Protective and strong responses were defined as an anti-HBs titer ≥10 mIU/mL and ≥100 mIU/mL, respectively and were evaluated one month after the third and the fourth doses. RESULTS: 163 HIV-infected individuals were evaluated 67 (40%) were male and median age was 37 years. Median CD4 cell count was 385 cells/mm(3) and 113 (70%) had undetectable HIV-1 viral load. Protective antibody response was observed in 83 and 91% and a strong antibody response was observed in 62 and 80% of the subjects after 3 and 4 doses, respectively. In a multivariate logistic model undetectable HIV-1 viral load and higher CD4 cell counts were independent predictors of a strong antibody response after 4 doses. Patients with undetectable HIV viral load were almost 3 times more likely to have anti-HBs titers above 100 mIU/mL than those with detectable viral load. CONCLUSIONS: A 4-double-dose regimen of a recombinant HBV vaccine increased response rates and determined higher antibody titers which may translate in prolonged protection against HBV. Inclusion of a fourth dose of HBV vaccine for HIV-infected subjects should be considered in the public health setting.
Subject(s)
HIV Infections/physiopathology , Hepatitis B Antibodies/blood , Hepatitis B Vaccines/administration & dosage , Hepatitis B/prevention & control , Vaccination/methods , Adult , Antibody Formation/immunology , Antiretroviral Therapy, Highly Active , CD4 Lymphocyte Count , Dose-Response Relationship, Immunologic , Female , HIV Infections/immunology , HIV Infections/virology , HIV-1/immunology , HIV-1/pathogenicity , Hepatitis B/immunology , Hepatitis B/virology , Hepatitis B Antibodies/immunology , Humans , Immunization Schedule , Male , Vaccines, Synthetic/administration & dosage , Viral LoadABSTRACT
We evaluated a modified HBV regimen in a cohort of HIV-infected subjects in Rio de Janeiro, Brazil. HIV-infected subjects with no serologic evidences of previous hepatitis B infection were immunized with 4 doses (40 microg each) of recombinant hepatitis B vaccine given at 0, 1, 2 and 6 months. Blood samples were collected 1 month after the last dose and anti-HBs titers were measured. A protective antibody response was defined as an anti-HBs titer >or=10 mIU/mL. Forty-seven subjects (30 women, 17 men; mean age was 36 years, ranging from 21 to 58 years) were included in the final analysis. Median baseline CD4+ lymphocyte count was 402 cells/mm(3) and 33 subjects (70%) had an HIV viral load below 80 copies/mL. A protective antibody response was observed in 42 (89%) subjects. Thirty-seven (78%) and 28 (60%) patients developed anti-HBs titers higher than 100 mIU/mL and 1000 mIU/mL, respectively. 1 out of 5 non-responders (20%) had an HIV viral load below the detection limit, in contrast with 32 (76%) of those with an adequate serologic response (p=0.02). These findings suggest that 4-double dose alternative schedule may be considered to overcome the lower seroconversion rates observed with the standard regimens in HIV-infected subjects.
