Objective: Lopinavir/ritonavir plus nucleoside reverse transcriptase inhibitors is one standard antiretroviral therapy regimen, both in patients with HIV alone and coinfected with hepatitis B or C. Our objective was to investigate whether hepatitis coinfection without clinical signs of hepatic impairment is a cofactor altering lopinavir pharmacokinetics and influencing therapy outcome.
Methods: Steady-state 12-hour pharmacokinetic profiles of lopinavir/ritonavir were assessed in patients with (group 1, n = 20) or without (group 2, n = 36) hepatitis coinfection, taking lopinavir/ritonavir 400/100 mg twice a day plus nucleoside reverse transcriptase inhibitors, measured by means of high-performance liquid chromatography-tandem mass spectrometry. Demographic (sex, age, weight), pharmacological (formulation, comedication), clinical, and virological/immunologic parameters (HIV-RNA PCR, CD4(+) cell count) were compared between the groups and included in regression analyses for correlations with lopinavir pharmacokinetic parameters (C(min), C(max), AUC, CL, and t(1/2)) and viral load evolution over 48 weeks on therapy. Patient pairs were matched 1:2 for the parameters sex, age, weight, ethnicity, and drug formulation.
Results: None of the hepatitis-related cofactors (aspartate aminotransferase, alanine aminotransferase, γGT, HBe Ag, HBsAg, HCV-RNA PCR, HCV-therapy) had an influence on lopinavir pharmacokinetics in this group of patients. Lopinavir C(min) (P = 0.039) and area under the curve (P = 0.038) and ritonavir C(max) (P = 0.049) were significantly enhanced in hepatitis-coinfected patients, but correlated only with drug formulation (ie, soft gel capsule or Meltrex tablet formulation, multivariate regression analysis, P = 0.001), not hepatitis coinfection.
Conclusions: Despite moderately enhanced lopinavir/ritonavir plasma concentrations, regular therapeutic drug monitoring is not to be considered in hepatitis-coinfected patients without hepatic impairment. Antiviral efficacy is comparable between both groups, a less-pronounced CD4(+) cell increase in hepatitis-coinfected patients is in line with previously published data.