High rates of serological response to a modified hepatitis B vaccination schedule in HIV-infected adults subjects

Abstract

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 (40μg 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 ≥10mIU/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 402cells/mm3 and 33 subjects (70%) had an HIV viral load below 80copies/mL. A protective antibody response was observed in 42 (89%) subjects. Thirty-seven (78%) and 28 (60%) patients developed anti-HBs titers higher than 100mIU/mL and 1000mIU/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.