The pharmacokinetics of peginterferon alfa‐2a and ribavirin in African American, Hispanic and Caucasian patients with chronic hepatitis C

Roche, Nutley, NJ, USA.
Alimentary Pharmacology & Therapeutics (Impact Factor: 5.73). 04/2012; 35(10):1209-20. DOI: 10.1111/j.1365-2036.2012.05079.x
Source: PubMed


Amongst Caucasian, Hispanic and African Americans with genotype 1 hepatitis C virus (HCV), there is a wide variation in response to treatment with peginterferon alfa-2a (PEG-IFN alfa-2a) and ribavirin.
To evaluate the pharmacokinetics (PK) of PEG-IFN alfa-2a and ribavirin among these three groups.
Forty-seven patients with genotype 1 CHC (17 African Americans, 14 Hispanics and 16 Caucasians) received 8 weeks of PEG-IFN alfa-2a (180 μg/week) and ribavirin (1000 or 1200 mg/day). PEG-IFN alfa-2a serum concentrations and ribavirin plasma concentrations were measured following the first dose and at week 8. Pharmacokinetic parameters (C(max), T(max), AUC, CL/F) were estimated using noncompartmental methods.
There was no difference in the pharmacokinetic parameters for PEG-IFN alfa-2a following single-dose or steady-state administration between African American or Hispanic patients compared with Caucasian patients. Ribavirin pharmacokinetic parameters were similar between Hispanic and Caucasian patients for single-dose and steady-state administration. The single-dose C(max) was 33% lower (P < 0.05) in African American compared with Caucasian patients. Other ribavirin single-dose and steady-state pharmacokinetic parameters were slightly decreased (approximately 20% lower) in African American patients, but were not considered clinically meaningful.
No differences were observed in PEG-IFN alfa-2a pharmacokinetic parameters between African American or Hispanic patients compared with Caucasian patients. For ribavirin, no differences were observed in pharmacokinetic parameters between Hispanic and Caucasian patients. While a trend towards increased ribavirin clearance and decreased exposure was observed in African American patients vs. Caucasian patients, the differences were small and not considered clinically meaningful (Clinical Trial Number: NP17354).

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Available from: Thomas Marbury, Oct 16, 2014
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