Telaprevir and ribavirin interaction: higher ribavirin levels are not only due to renal dysfunction during triple therapy.

A higher incidence of anemia has been observed during the treatment of hepatitis C virus genotype 1 (HCV-1) infection with pegylated alpha interferon (pegIFN-α), ribavirin, and telaprevir. We assessed the impacts that concomitant administration of telaprevir and changes in the glomerular filtration rate have on ribavirin plasma levels. The minimum concentrations of ribavirin in plasma (ribavirin Cmin) determined during triple therapy including telaprevir were compared with those observed after telaprevir withdrawal and those observed in the same subjects and in a large cohort during a previous course of pegIFN-α plus ribavirin.

Role of ritonavir in the drug interactions between telaprevir and ritonavir-boosted atazanavir.

Background: Detrimental bidirectional pharmacokinetic interactions have been observed when telaprevir (TVR) and ritonavir (RTV)-boosted human immunodeficiency virus (HIV) protease inhibitors are coadministered in healthy volunteers. Our aim was to evaluate the role of RTV in the bidirectional TVR and atazanavir (ATV) interactions.

Method: An open-label, sequential study was carried out in hepatitis C virus (HCV)/HIV-coinfected patients on a RTV-boosted ATV-based (ATVr) antiretroviral regimen (300/100 mg every 24 hours) and triple therapy for chronic C hepatitis genotype 1 (TVR, 1125 mg every 12 hours, pegylated interferon-alpha and ribavirin).

The effects of liver impairment on the pharmacokinetics of brivanib, a dual inhibitor of fibroblast growth factor receptor and vascular endothelial growth factor receptor tyrosine kinases.

Purpose: Hepatic impairment may impede tyrosine kinase inhibitor metabolism. This phase I study compared the pharmacokinetics of brivanib in patients with hepatocellular carcinoma (HCC) and varying levels of hepatic impairment with those with non-HCC malignancies and normal liver function.

Methods: Patients were assigned to the following groups: Groups A, B, and C (HCC plus mild, moderate, or severe hepatic impairment, respectively) and Group D (non-HCC malignancy and normal hepatic function).

Intracellular and plasma pharmacokinetics of 400 mg of etravirine once daily versus 200 mg of etravirine twice daily in HIV-infected patients.

Objectives: To compare intracellular and plasma etravirine concentrations when etravirine was given at 200 mg/12 h versus 400 mg/24 h and to evaluate whether the results would support once-daily dosing.

Methods: This was an open-label sequential study in which eight patients on protease inhibitor (PI)-sparing regimens containing etravirine were included. Full pharmacokinetic profiles were performed while on 200 mg of etravirine/12 h and after switching to 400 mg of etravirine/24 h.