Drug-drug interactions and drug resistance will limit access to treatment in patients with HIV and hepatitis C virus coinfection

A Cross-Sectional Study Comparing the Frequency of Drug Interactions After Adding Simeprevir- or Sofosbuvir-Containing Therapy to Medication Profiles of Hepatitis C Monoinfected Patients

INTRODUCTION

This study compares the expected occurrence of contraindicated drug-drug interactions (XDDIs) when simeprevir (SIM)- or sofosbuvir (SOF)-containing therapy is added to medication profiles of patients with hepatitis C (HCV) monoinfection to quantify, in relative terms, the population-based risk of XDDIs. Second, this study identified the predictors of XDDIs when HCV therapies are added to medication profiles.

METHODS

A cross-sectional study was performed among Veterans' Affairs patients. Inclusion criteria were: (1) age ≥18 years, (2) HCV infection, and (3) availability of a medication list. Patients with human immunodeficiency virus were excluded. Demographics, comorbidities, year of HCV diagnosis, and most recent medication list were collected from medical records. The primary outcome was the presence of XDDIs involving HCV therapy and the medications in the patient's home medication list after the addition of either SIM- or SOF-containing regimens. To define XDDIs, Lexi-Interact drug interaction software was used.

RESULTS

4,251 patients were included. The prevalence of XDDIs involving SIM- or SOF-containing therapy were 12.6% and 4.7% (p < 0.001), respectively. In multivariable analyses examining the predictors of XDDIs involving SIM-containing therapy, the only medication-related predictor was use of ≥6 home medications (odds ratio OR 4.58, 95% confidence interval CI 3.54-5.20, p < 0.001). Similarly, use of ≥6 home medications was also the only variable associated with an increased probability of XDDI involving SOF-containing therapy (OR 3.83, 95% CI 2.57-5.70, p < 0.001).

CONCLUSIONS

Sofosbuvir-containing therapy had a lower frequency of XDDIs than SIM-containing therapy. Polypharmacy with various classes of home medications predicted XDDIs involving SIM- or SOF-containing therapy.

Therapeutic potential of and treatment with boceprevir/telaprevir-based triple-therapy in HIV/chronic hepatitis C co-infected patients in a real-world setting

The aim of this study was to assess the therapeutic potential of telaprevir (TPV)/boceprevir (BOC)-based triple-therapy in a complete cohort of HIV/chronic hepatitis C co-infected patients (HIV/HCV). Moreover, a case series of four HIV/HCV genotype (HCV-GT)1 patients with rapid virologic response (RVR), who received only 28 weeks of BOC-based triple-therapy (BOCW28), was reported. 290/440 HIV-positive patients with positive HCV serology had at least one visit during the past 2 years, 142/290 had target detectable HCV-RNA with 64% (82/142) carrying HCV-GT1. While 18 HIV/HCV-GT1 displayed contraindications, 45% (64/142) of HIV/HCV were eligible for triple-therapy. Insufficiently controlled HIV-infection despite combined antiretroviral therapy (cART) (HIV-RNA <50 copies/mL: 73% vs. 22%; p<0.001) and liver cirrhosis (31% vs. 8%; p=0.025) were overrepresented among patients with contraindications for triple-therapy. Low treatment uptake rates (39% (25/64)) during the first 2 years of triple-therapy availability suggest that its benefit in HIV/HCV co-infected patients might fall short of expectations. Modification of cART or TPV dose adjustment would have been necessary in 61% and 84% of HIV/HCV-GT1 on cART eligible for triple-therapy using TPV and BOC, respectively, suggesting that drug-drug interactions with cART complicate management in the majority of patients. All four BOCW28 patients achieved a sustained virologic response. Prospective studies are necessary to validate our observations on the shortening of treatment duration in HIV/HCV-GT1 with RVR.

Strategies for assignment of HIV-HCV genotype-1-coinfected patients to either dual-therapy or direct-acting antiviral agent-based triple-therapy

BACKGROUND

The aim of this study was to evaluate strategies for assignment of HIV-HCV genotype-1-coinfected patients (HIV-HCV-GT1) to either dual-therapy or direct-acting antiviral agent (DAA)-based triple-therapy.

METHODS

A total of 148 treatment-naive HIV-HCV-GT1 who received antiviral therapy with pegylated interferon/ribavirin were included in this multinational, retrospective analysis. Patients with rapid virological response (RVR) were treated for 48 weeks, while patients without RVR received either 48 or 72 weeks of treatment. IL28B rs12979860 (IL28B) non-C/C, advanced liver fibrosis and high HCV RNA were considered as established risk factors for treatment failure.

RESULTS

A trend toward higher sustained virological response (SVR) rates in patients with IL28B C/C (65% [37/57] versus 51% [40/79]; P=0.097) was observed. Higher SVR rates were observed in patients without advanced liver fibrosis (61% [47/77] versus 42% [22/52]); P=0.036) and without high HCV RNA (73% [35/48] versus 49% [49/100]; P=0.006), as well as in patients with RVR (90% [35/39] versus 45% [49/109]; P<0.001). SVR rates varied statistically significantly between the risk factors for treatment failure subgroups (86% [6/7] versus 69% [34/49] versus 48% [21/44] versus 20% [4/20] for zero, one, two and three risk factors, respectively; P<0.001). In patients without RVR, higher rates of SVR were observed in those treated for 72 weeks (62% [23/37]), when compared to patients treated for 48 weeks (36% [26/72]; P=0.01).

CONCLUSIONS

RVR had an excellent positive predictive value for the response to dual-therapy in HIV-HCV-GT1, emphasizing the utility of a lead-in phase for assigning these patients to dual-therapy or DAA-based triple-therapy. The use of an IL28B-guided approach was suboptimal, while a combination of established baseline predictors may provide guidance for individual treatment decisions prior to the initiation of antiviral therapy. However, the extension of treatment duration to 72 weeks in HIV-HCV-GT1 without RVR should be strongly considered if triple-therapy is not available.