Lack of a clinically significant drug-drug interaction in healthy volunteers between the HCV protease inhibitor boceprevir and the proton pump inhibitor omeprazole.

OBJECTIVES Proton pump inhibitors (PPIs) can limit the solubility of concomitant drugs, which can lead to decreased absorption and exposure. Reduced efficacy can be a consequence and in the case of an antimicrobial agent this may contribute to development of resistance. Patients chronically infected with the hepatitis C virus can be treated with a boceprevir-containing regimen and it is relevant to know if interactions between PPIs and boceprevir exist. This study was designed to investigate the influence of a frequently used PPI, omeprazole, on the pharmacokinetics of boceprevir and vice versa. METHODS In this open-label, three-period, randomized, cross-over, Phase I study, healthy subjects were randomly assigned to 40 mg of omeprazole once daily for 5 days, 800 mg of boceprevir three times daily for 5 days and 40 mg of omeprazole once daily + 800 mg of boceprevir three times daily for 5 days, or the same treatment in a different order. Every treatment was followed by a wash-out period. At day 5 of every treatment pharmacokinetic blood sampling was performed for 8 h after medication intake. ClinicalTrials.gov: NCT01470690. RESULTS All 24 subjects (15 males) completed the study and no serious adverse events were reported. Geometric mean ratios (90% CI) of the area under the plasma concentration-time curve up to 8 h (AUC0-8) and maximum plasma concentration (Cmax) of boceprevir with omeprazole versus boceprevir alone were 0.92 (0.87-0.97) and 0.94 (0.86-1.02), respectively. For omeprazole these values were 1.06 (0.90-1.25) for AUC0-8 and 1.03 (0.85-1.26) for Cmax for the combination versus omeprazole alone. CONCLUSIONS Omeprazole did not have a clinically significant effect on boceprevir exposure, and boceprevir did not affect omeprazole exposure.