Drug-drug interactions of telaprevir and boceprevir in HCV-monoinfected and HIV/HCV-coinfected patients can modify the adherence.

Abstract

The first generation protease inhibitors, boceprevir (BOC) and telaprevir (TVR), are both CYP3A4 inhibitors, which predispose drug-drug interactions (DDIs). The aim of this study was to evaluate the prevalence of potential DDIs, the management of outpatient medication and its impact on adherence and efficacy to antiviral treatment in hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients receiving BOC and TVR. The usual medication starting with BOC or TVR was screened by the pharmacist of the multidisciplinary support programme (MSP) for potential DDIs. Recommendations were made to avoid significant DDIs, and changes in the baseline medication were recorded. Adherence to antiviral treatment was considered as 80/80/95% of total doses. Sustained virological response was assessed at week 12 (SVR12). At least one potential DDI was found in 70 (64.8%) patients, 45 (54.2%) being HCV-monoinfected and 25 (100%) HIV/HCV-coinfected (P < 0.01). Baseline treatment modifications were required in 38 (35.2%) patients. Adherence and SVR12 were higher in patients without DDIs (86.8%) and (67.6%) compared to those with DDIs (62.8%) (P = 0.021) and (47.2%) (P = 0.097) respectively. More than half of the patients were at risk of presenting DDIs, leading to changes in the baseline medication in one-third of the patients. Drug interactions are frequent in patients with lower adherence.