Non-invasive tests accurately stratify patients with NAFLD based on their risk of liver-related events.

BACKGROUND & AIMS: Previous studies on the prognostic significance of non-invasive liver fibrosis tests in non-alcoholic fatty liver disease (NAFLD) lack direct comparison to liver biopsy. We aimed to evaluate the prognostic accuracy of fibrosis-4 (FIB4) and vibration-controlled transient elastography (VCTE), compared to liver biopsy, for the prediction of liver-related events (LREs) in NAFLD. METHODS: A total of 1,057 patients with NAFLD and baseline FIB4 and VCTE were included in a multicenter cohort. Of these patients, 594 also had a baseline liver biopsy. The main study outcome during follow-up was occurrence of LREs, a composite endpoint combining cirrhosis complications and/or hepatocellular carcinoma. Discriminative ability was evaluated using Harrell's C-index. RESULTS: FIB4 and VCTE showed good accuracy for the prediction of LREs, with Harrell's C-indexes >0.80 (0.817 [0.768-0.866] vs. 0.878 [0.835-0.921], respectively, p = 0.059). In the biopsy subgroup, Harrell's C-indexes of histological fibrosis staging and VCTE were not significantly different (0.932 [0.910-0.955] vs. 0.881 [0.832-0.931], respectively, p = 0.164), while both significantly outperformed FIB4 for the prediction of LREs. FIB4 and VCTE were independent predictors of LREs in the whole study cohort. The stepwise FIB4-VCTE algorithm accurately stratified the risk of LREs: compared to patients with "FIB4 <1.30", those with "FIB4 ≥1.30 then VCTE <8.0 kPa" had similar risk of LREs (adjusted hazard ratio [aHR] 1.3; 95% CI 0.3-6.8), whereas the risk of LREs significantly increased in patients with "FIB4 ≥1.30 then VCTE 8.0-12.0 kPa" (aHR 3.8; 95% CI 1.3-10.9), and even more for those with "FIB4 ≥1.30 then VCTE >12.0 kPa" (aHR 12.4; 95% CI 5.1-30.2). CONCLUSION: VCTE and FIB4 accurately stratify patients with NAFLD based on their risk of LREs. These non-invasive tests are alternatives to liver biopsy for the identification of patients in need of specialized management. LAY SUMMARY: The amount of fibrosis in the liver is closely associated with the risk of liver-related complications in non-alcoholic fatty liver disease (NAFLD). Liver biopsy currently remains the reference standard for the evaluation of fibrosis, but its application is limited by its invasiveness. Therefore, we evaluated the ability of non-invasive liver fibrosis tests to predict liver-related complications in NAFLD. Our results show that the blood test FIB4 and transient elastography stratify the risk of liver-related complications in NAFLD, and that transient elastography has similar prognostic accuracy as liver biopsy. These results support the use of non-invasive liver fibrosis tests instead of liver biopsy for the management of patients with NAFLD.

Obeticholic Acid Impact on Quality of Life in Patients With Nonalcoholic Steatohepatitis: REGENERATE 18-Month Interim Analysis.

BACKGROUND & AIMS: Nonalcoholic steatohepatitis (NASH) affects patients' health-related quality of life (HRQoL). Patient-reported outcomes (PROs) evaluating HRQoL were assessed in the RandomizEd Global Phase 3 Study to Evaluate the Impact on NASH with FibRosis of Obeticholic Acid TreatmEnt (REGENERATE) study, which showed that obeticholic acid (OCA) significantly improved fibrosis in patients with NASH. METHODS: Noncirrhotic NASH patients in a phase 3, double-blind, randomized, placebo-controlled, multicenter, international study of OCA were enrolled. The Chronic Liver Disease Questionnaire-NASH and EuroQol EQ-5D-5L were administered at baseline, 6, 12, and 18 months. RESULTS: There were 1218 patients (age, 54.1 ± 11.5 y; 57% women; 43% stage F3) in the expanded intent-to-treat population (stages, F1-F3) assigned randomly to 10 mg (N = 407) or 25 mg (N = 404) OCA or placebo (N = 407). Baseline measurements were balanced across treatment groups for EuroQol EQ-5D-5L and Chronic Liver Disease Questionnaire-NASH, including Itch score: 5.75 ± 1.53 (scale 1-7, with 7 representing no itching). Nineteen (1.6%) patients discontinued therapy (protocol mandated) because of grade 3 pruritus. Patients receiving 25 mg OCA experienced mild worsening of itch scores primarily in the first months of treatment: mean ± SE change from baseline -0.66 ± 0.12, -0.44 ± 0.12, and -0.42 ± 0.13 at 6, 12, and 18 months, respectively (all P < .01). No other PRO worsening was associated with 25 mg OCA. Patients experiencing fibrosis improvement, Nonalcoholic Fatty Liver Disease Activity Score decrease (by ≥2 points), or NASH resolution had greater PRO improvements in some domains. CONCLUSIONS: NASH patients evaluated in REGENERATE had impaired quality of life and underlying pruritus at baseline. Improvement of NASH corresponded with improvement in several HRQoL domains. Generally mild pruritus occurs early after OCA therapy initiation and does not worsen over time. CLINICALTRIALS: gov: NCT02548351.

Non-invasive evaluation of response to obeticholic acid in patients with NASH: Results from the REGENERATE study.

BACKGROUND & AIMS: Non-alcoholic steatohepatitis (NASH) is a chronic, progressive fibrotic liver disease that can lead to cirrhosis. While liver biopsy is considered the reference standard for the histologic diagnosis of NASH and staging of fibrosis, its use in clinical practice is limited. Non-invasive tests (NITs) are increasingly being used to identify and stage liver fibrosis in patients with NASH, and several can assess liver-related outcomes. We report changes in various NITs in patients treated with obeticholic acid (OCA) or placebo in the phase III REGENERATE study. METHODS: Patients with NASH and fibrosis stage F2 or F3 (n = 931) were randomized (1:1:1) to receive placebo, OCA 10 mg, or OCA 25 mg once daily. Various NITs based on clinical chemistry and/or imaging were evaluated at baseline and throughout the study. RESULTS: Rapid, sustained reductions from baseline in alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma-glutamyltransferase levels, as well as in Fibrosis-4 (FIB-4), FibroTest, FibroMeter, and FibroScan-AST scores were observed in OCA-treated vs. placebo-treated patients. Reduction in liver stiffness by vibration-controlled transient elastography was observed in the OCA 25 mg group vs. the placebo group at Month 18. NIT changes were associated with shifts in histologic fibrosis stage. The greatest improvements were observed in patients with ≥1-stage fibrosis improvement; however, improvements in ALT, AST, FIB-4, and FibroTest were also observed in OCA-treated patients whose histologic fibrosis remained stable. CONCLUSIONS: Based on the REGENERATE Month 18 interim analysis, rapid and sustained improvements in various NITs were observed with OCA treatment. Dynamic changes in selected NITs separated histologic responders from non-responders. These results suggest that NITs may be useful in assessing histologic response to OCA therapy. CLINICALTRIALS. GOV NUMBER: NCT02548351 LAY SUMMARY: Non-alcoholic steatohepatitis (NASH) is a chronic, progressive liver disease that can lead to cirrhosis. To diagnose and assess liver fibrosis (scarring) in patients with NASH, non-invasive tests (NITs) are increasingly being used rather than liver biopsy, which is invasive, expensive, and can be risky. In the REGENERATE study, which is evaluating the effects of obeticholic acid vs. placebo in patients with NASH, various NITs were also evaluated. This analysis shows that improvements in levels of certain blood components, as well as favorable results of ultrasound imaging and proprietary tests of liver function, were associated with improvements in liver fibrosis after treatment with obeticholic acid, suggesting that NITs may be useful alternatives to liver biopsy in assessing NASH patients' response to therapy.

Deep-sequencing reveals broad subtype-specific HCV resistance mutations associated with treatment failure.

A percentage of hepatitis C virus (HCV)-infected patients fail direct acting antiviral (DAA)-based treatment regimens, often because of drug resistance-associated substitutions (RAS). The aim of this study was to characterize the resistance profile of a large cohort of patients failing DAA-based treatments, and investigate the relationship between HCV subtype and failure, as an aid to optimizing management of these patients. A new, standardized HCV-RAS testing protocol based on deep sequencing was designed and applied to 220 previously subtyped samples from patients failing DAA treatment, collected in 39 Spanish hospitals. The majority had received DAA-based interferon (IFN) α-free regimens; 79% had failed sofosbuvir-containing therapy. Genomic regions encoding the nonstructural protein (NS) 3, NS5A, and NS5B (DAA target regions) were analyzed using subtype-specific primers. Viral subtype distribution was as follows: genotype (G) 1, 62.7%; G3a, 21.4%; G4d, 12.3%; G2, 1.8%; and mixed infections 1.8%. Overall, 88.6% of patients carried at least 1 RAS, and 19% carried RAS at frequencies below 20% in the mutant spectrum. There were no differences in RAS selection between treatments with and without ribavirin. Regardless of the treatment received, each HCV subtype showed specific types of RAS. Of note, no RAS were detected in the target proteins of 18.6% of patients failing treatment, and 30.4% of patients had RAS in proteins that were not targets of the inhibitors they received. HCV patients failing DAA therapy showed a high diversity of RAS. Ribavirin use did not influence the type or number of RAS at failure. The subtype-specific pattern of RAS emergence underscores the importance of accurate HCV subtyping. The frequency of "extra-target" RAS suggests the need for RAS screening in all three DAA target regions.

Effectiveness and safety of elbasvir/grazoprevir therapy in patients with chronic HCV infection: Results from the Spanish HEPA-C real-world cohort.

In randomized controlled trials of patients with chronic HCV infection, elbasvir/grazoprevir (EBR/GZR) demonstrated high cure rates and a good safety profile. This study assessed the effectiveness and safety of EBR/GZR, with and without ribavirin, in a real-world HCV patient cohort. HEPA-C is a collaborative, monitored national registry of HCV patients directed by the Spanish Association for the Study of the Liver and the Networked Biomedical Research Centre for Hepatic and Digestive Diseases. Patients entered into HEPA-C between December 2016 and May 2017, and treated with EBR/GZR with at least end-of-treatment response data, were included. Demographic, clinical and virologic data were analysed, and adverse events (AEs) recorded. A total of 804 patients were included in the study. The majority were male (57.9%), with a mean age of 60 (range, 19-92) years. Genotype (GT) distribution was GT 1, 86.8% (1a, 14.3%; 1b, 72.5%); GT 4, 13.2% and 176 patients (21.9%) were cirrhotic. Overall, among 588 patients with available data, 570 (96.9%) achieved sustained virologic response at 12 weeks post-treatment (SVR12). SVR12 rates by genotype were GT 1a, 97.7%; GT 1b, 98.6%; and GT 4, 98.1%. No significant differences in SVR12 according to fibrosis stage were observed. Eighty patients experienced an AE, resulting in treatment discontinuation in three. In this large cohort of patients with chronic HCV managed in a real-world setting in Spain, EBR/GZR achieved high rates of SVR12, comparable to those observed in randomized controlled trials, with a similarly good safety profile.

Simplified follow-up of patients with mild chronic hepatitis C in areas with limited access to antiviral therapy.

BACKGROUND AND AIMS: In some areas of the world, antiviral therapy for chronic hepatitis C (CHC) is not available for all patients. The optimal interval for liver stiffness measures (LSM) and noninvasive scores to assess fibrosis progression has not been studied. We evaluated the usefulness of consecutive LSM, APRI, FIB-4 and Forns scores to predict disease progression. METHODS: Patients with CHC and at least two annual LSM within 3 years were followed for a minimum of 5 years. Noninvasive scores were assessed. Evolution of LSM and scores were expressed as change/year (Delta). RESULTS: 623 non-cirrhotic patients were included. Median baseline LSM was 6.6 kPa (IQR 5.4-8.4). During a median follow-up of 6 years, 61(9.7%) patients developed cirrhosis. Baseline LSM ≥ F2 and Forns ≥ 6.9 were the main predictors of cirrhosis (C-index 0.97). The addition of Delta variables did not improve its prediction. In patients with mild fibrosis (F0-1), progression to ≥F2 occurred in 80 (23%) within the first 3 years. Baseline BMI ≥ 24 kg/m2 and LSM ≥ 5.9 kPa were associated to progression. CONCLUSIONS: Baseline LSM and Forns are highly predictive of cirrhosis development. In patients with mild CHC, BMI < 24 and LSM < 5.9, the likelihood of progression is very low, allowing for a significant spacing of noninvasive assessments over time.

Long-Term Outcomes of Patients With HCV-Associated Cryoglobulinemic Vasculitis After Virologic Cure.

Patients with hepatitis C virus-associated cryoglobulinemic vasculitis (HCV-CV) have high rates of clinical remission after treatment with direct-acting antivirals (DAAs), but circulating cryoglobulins persist, and vascular disorders reappear in some patients shortly after DAA treatment ends. We performed a prospective study to assess the long-term clinical and immune system effects of HCV eradication with DAAs in 46 patients with HCV-CV and 42 asymptomatic patients with circulating cryoglobulins. A median of 24 months after DAA treatment (range, 17-41 months), 66% of patients with HCV-CV and 70% of asymptomatic patients with circulating cryoglobulins had an immunologic response, with comparable reductions in cryocrit from 2.6% to 0% (P < .05). However, 20% of patients still had positive test results for cryoglobulins after DAA therapy. Among patients with HCV-CV, 42 (91%) had a clinical response, in that their Birmingham Vasculitis Activity Score (version 3) decreased from 7 to 0 (P < .01). Nevertheless, within 2 years after a sustained viral response to DAA therapy, 5 patients with HCV-CV (11%, 4 with cirrhosis) had relapses of vasculitis that included severe organ damage and death.

Shorter hepatitis B immunoglobulin administration is not associated to hepatitis B virus recurrence when receiving combined prophylaxis after liver transplantation.

BACKGROUND & AIMS: The combination of hepatitis B immunoglobulin and a nucleos(t)ide analogues has markedly reduced the rate of hepatitis B virus recurrence after liver transplantation; however, the optimal duration of hepatitis B immunoglobulin has not been clarified. This lack of consensus perpetuates the use of different strategies. The aim of this study was to evaluate the risk factors associated to hepatitis B virus recurrence after liver transplantation in a large cohort of patients under different hepatitis B immunoglobulin regimens. METHODS: Retrospective multicentre analysis of hepatitis B virus-related liver transplantation recipients receiving combined prophylaxis (hepatitis B immunoglobulin + nucleos(t)ide analogues). The strategy of short-term hepatitis B immunoglobulin was compared to lifelong administration. Hepatitis B virus recurrence was defined as positive HBsAg after liver transplantation. RESULTS: Three hundred and thirty-eight patients were analysed. After a median follow-up period of 72 months, 37 patients (11%) developed hepatitis B virus recurrence. Hepatocellular carcinoma recurrence and lamivudine resistance after liver transplantation were the only factors independently associated to hepatitis B virus recurrence (HR 5.4 [2.3-12] and 9.3 [4.2-20] respectively P < .001). HBsAg reappearance after hepatitis B virus recurrence was transient (16 patients), persistent (15) or alternant (6). The hepatitis B immunoglobulin regimen did not have an impact on the rate or evolution of hepatitis B virus recurrence. Overall, patient survival was good and not influenced by hepatitis B virus recurrence (82% at 5 years). Fulminant liver failure, hepatitis C coinfection or hepatocellular carcinoma at liver transplantation were independent risk factors for lower survival. CONCLUSIONS: Liver transplantation is an effective treatment for hepatitis B virus-related liver disease. Since the introduction of combined prophylaxis the rate of hepatitis B virus recurrence is very low. However, lifelong hepatitis B immunoglobulin administration does not seem necessary to reduce hepatitis B virus recurrence.

Impact of comorbidities on patient outcomes after interferon-free therapy-induced viral eradication in hepatitis C.

BACKGROUND & AIMS: Patients with advanced liver fibrosis remain at risk of cirrhosis-related outcomes and those with severe comorbidities may not benefit from hepatitis C (HCV) eradication. We aimed to collect data on all-cause mortality and relevant clinical events within the first two years of direct-acting antiviral therapy, whilst determining the prognostic capability of a comorbidity-based model. METHODS: This was a prospective non-interventional study, from the beginning of direct-acting antiviral therapy to the event of interest (mortality) or up to two years of follow-up, including 14 Spanish University Hospitals. Patients with HCV infection, irrespective of liver fibrosis stage, who received direct-acting antiviral therapy were used to build an estimation and a validation cohort. Comorbidity was assessed according to Charlson comorbidity and CirCom indexes. RESULTS: A total of 3.4% (65/1,891) of individuals died within the first year, while 5.4% (102/1,891) died during the study. After adjusting for cirrhosis, platelet count, alanine aminotransferase and sex, the following factors were independently associated with one-year mortality: Charlson index (hazard ratio [HR] 1.55; 95% CI 1.29-1.86; p = 0.0001), bilirubin (HR 1.39; 95% CI 1.11-1.75; p = 0.004), age (HR 1.06 95% CI 1.02-1.11; p = 0.005), international normalized ratio (HR 3.49; 95% CI 1.36-8.97; p = 0.010), and albumin (HR 0.18; 95% CI 0.09-0.37; p = 0.0001). HepCom score showed a good calibration and discrimination (C-statistics 0.90), and was superior to the other prognostic scores (model for end-stage liver disease 0.81, Child-Pugh 0.72, CirCom 0.68) regarding one- and two-year mortality. HepCom score identified low- (≤5.7 points: 2%-3%) and high-risk (≥25 points: 56%-59%) mortality groups, both in the estimation and validation cohorts. The distribution of clinical events was similar between groups. CONCLUSIONS: The HepCom score, a combination of Charlson comorbidity index, age, and liver function (international normalized ratio, albumin, and bilirubin) enables detection of a group at high risk of one- and two-year mortality, and relevant clinical events, after starting direct-acting antiviral therapy. LAY SUMMARY: The prognosis of patients with severe comorbidities may not benefit from HCV viral clearance. An algorithm to decide who will benefit from the treatment is needed to manage the chronic HCV infection better.

Correction: Neutrophil and Monocyte Function in Patients with Chronic Hepatitis C Undergoing Antiviral Therapy with Regimens Containing Protease Inhibitors with and without Interferon.

[This corrects the article DOI: 10.1371/journal.pone.0166631.].

Virologic, Clinical, and Immune Response Outcomes of Patients With Hepatitis C Virus-Associated Cryoglobulinemia Treated With Direct-Acting Antivirals.

BACKGROUND & AIMS: Cryoglobulins (circulating immune complexes of polyclonal IgG, monoclonal IgM, and rheumatoid factor) are detected in the circulation of 40% to 60% of patients with chronic hepatitis C virus infection, and cryoglobulinemic vasculitis (CV) is observed in approximately 10% of patients. We aimed to assess the clinical and immune effects of direct-acting antiviral treatment. METHODS: We performed a prospective study of 64 patients with HCV infection with circulating cryoglobulins receiving direct-acting antiviral therapy at a single center in Barcelona, Spain, from January 2014 through April 2016. Patients were classified as having CV (n = 35) or asymptomatic circulating cryoglobulins (ACC, n = 29). Clinical response was considered complete if a patient's Birmingham Vasculitis Activity Score (version 3) was 0, or if all affected organs improved 12 weeks after the end of therapy. A complete immunologic response (CIR) was defined as no detection of circulating cryoglobulins and normalized levels of complement and/or rheumatoid factor. RESULTS: Clinical manifestations of CV included purpura (65%), weakness (70%), arthralgia (31%), myalgia (20%), peripheral neuropathy (50%), and renal involvement (20%). At baseline, patients with CV had significantly higher levels of rheumatoid factor and lower levels of C4 complement than patients with ACC, whereas cryocrits were similar between groups (3.2% vs 2.6%). Overall, 60 patients (94%) had a sustained viral response 12 weeks after therapy. Among patients with CV, the median Birmingham Vasculitis Activity Score (version 3) decreased from 9 (range, 2-31) to 3 (range, 0-12) (P < .001). Twenty-five patients with CV (71%) achieved a complete clinical response. Immune-suppressive therapy was reduced for 4 of 13 patients and withdrawn for 6 of 13. Overall, 48% of patients achieved a CIR. A low baseline cryocrit level (<2.7%) was the only factor associated with CIR (odds ratio, 9.8; 95% confidence interval, 2.2-44; P = .03). CONCLUSIONS: Viral eradication was associated with clinical improvement in most patients with CV. Markers of immune activation, including circulating cryoglobulins, persisted in 52% of patients with CV or ACC, despite a sustained viral response 12 weeks after therapy. A longer follow-up period after viral eradication might be necessary to ensure a normal immune response.

Neutrophil and Monocyte Function in Patients with Chronic Hepatitis C Undergoing Antiviral Therapy with Regimens Containing Protease Inhibitors with and without Interferon.

Real-life data showed an increased incidence of bacterial infections in patients with advanced liver disease receiving a protease inhibitor (PI)-containing antiviral regimen against hepatitis C (HCV). However, the causes of this event are unknown. We hypothesized that PIs might impair innate immune responses through the inhibition of proteases participating in the anti-bacterial functions of neutrophils and monocytes. The aims of the study were to assess phagocytic and oxidative burst capacity in neutrophils and monocytes obtained from patients receiving a PI containing-antiviral regimen, and to determine cytokine secretion after neutrophil stimulation with flagellin. Forty patients with chronic HCV (80% with cirrhosis) were enrolled in the study, 28 received triple therapy (Group A) with pegylated-interferon and ribavirin for 4 weeks followed by the addition of a PI (telaprevir, boceprevir or simeprevir), and 12 patients received an interferon-free regimen (Group B) with simeprevir and sofosbuvir. Phagocytosis and oxidative burst capacity were analyzed by flow cytometry at baseline, week 4, and week 8 of therapy. In neutrophils from Group A patients, oxidative burst rate and oxidative enzymatic activity per cell significantly decreased throughout the study period (p = 0.014 and p = 0.010, respectively). Pairwise comparisons showed a decrease between baseline and week 4 and 8 of therapy. No differences were observed after the introduction of the PI. The oxidative enzymatic activity per cell in monocytes significantly decrease during the study period (p = 0.042) due to a decrease from baseline to week 8 of therapy (p = 0.037) in patients from Group A. None of these findings were observed in Group B patients. Cytokine secretion did not significantly change during the study in both groups. In conclusion, our data suggest that the use interferon (rather than the PI) has a deleterious effect on neutrophil and monocyte phagocytic and oxidative burst capacity in this cohort of patients with HCV-related advanced liver fibrosis.

Challenges in Special Populations: HIV/HCV Coinfection, Liver Transplantation and Patients with End-Stage Renal Disease.

Until recently, the combination of PEG-interferon and ribavirin (RBV) was the main treatment for all genotypes of chronic hepatitis C virus (HCV) infection. Sustained virological response (SVR) rates varied signixFB01;cantly across patient subgroups and the concept of 'special populations' emerged. Now, in the era of direct acting antivirals, with a better safety profile and higher efficacy rates, those patients with comorbidities or conditions that limited IFN-based antiviral treatment but with unmet medical needs have been considered for therapy again. With the currently approved all-oral antivirals, patients coinfected with human immunodeficiency virus and HCV have SVR rates similar to patients with HCV monoinfection. However, drug-drug interactions (DDIs) with antiretroviral drugs are still challenging. In the setting of liver transplantation, with an accelerated course of hepatitis C, previous IFN-RBV treatments were poorly tolerated and attained low SVR rates. Today, all-oral therapies have proven to be efficacious and safe in this population. Nevertheless, questions such as the optimal treatment duration or the need for RBV still remain opened. In this population as well, DDIs are an issue, as some regimens require adjustments and monitoring of immunosuppressive drugs during therapy. Finally, preliminary data show promising results in terms of efficacy and safety in patients with end-stage renal disease. However, there is clear need for more clinical studies since treatment options are still very limited.

Antiviral treatment with sofosbuvir and simeprevir in a kidney transplant recipient with HCV-decompensated cirrhosis: viral eradication and removal from the liver transplant waiting list.

Hepatitis C positive kidney transplant (KT) recipients are a difficult-to-treat subpopulation. Interferon-based therapies are contraindicated (or at least not used) in KT patients, due to the risk of allograft rejection, its poor tolerability and the low rates of sustained virological response (SVR) achieved with these therapies. Nevertheless, the use of direct-acting antiviral drugs (DAAs) will certainly provide new opportunities for hepatitis C treatment in the KT setting. Here, we report the case of a KT recipient with decompensated cirrhosis who received antiviral therapy with sofosbuvir, simeprevir, and ribavirin during 24 weeks while awaiting liver transplantation. Hepatitis C was eradicated, and the patient was removed from the transplant list. Although there is no safety and efficacy data regarding the use of DAAs in the KT setting, this case suggests that KT recipients may benefit from the use of new antiviral drugs with high SVR rates and an excellent safety profile.