Influence of viral chronic hepatitis co-infection on plasma drug concentrations and liver transaminase elevations upon therapy switch in HIV-positive patients

It is still controversial whether viral hepatitis co-infection can influence antiretroviral plasma drug concentrations and whether drug concentrations are correlated with liver enzyme elevations during highly active antiretroviral therapy. An analysis of data from a cohort of 220 human immunodeficiency virus (HIV)-infected patients was conducted. Univariate and multivariate logistic analyses were performed to identify predictors of plasma drug concentrations. The association of transaminase elevation with higher plasma drug concentrations was explored following stratification of patients into HIV monoinfected and hepatitis C virus (HCV) and/or hepatitis B virus (HBV) co-infected groups. Hepatitis co-infections were independently correlated with drug concentrations above the therapeutic cut-offs at Week 1 (P = 0.06), Week 4 (P = 0.04) and Week 12 (P = 0.005). The apparent effect was independent of the possible impact exerted by other variables such as demographics and medication adherence. The incidence of relevant hypertransaminasaernia was low. Patients with hepatitis co-infections had higher rates of transaminase elevation than monoinfected HIV patients; however, risk of transaminase elevation was not associated with drug concentrations. The presence of HCV and/or HBV co-infections correlated with higher plasma drug concentrations, although it did not appear to influence hepatotoxicity risk. (c) 2006 Published by Elsevier B.V. and the International Society of Chemotherapy.