Efficacy and safety of 12 weeks versus 18 weeks of treatment with grazoprevir (MK-5172) and elbasvir (MK-8742) with or without ribavirin for hepatitis C virus genotype 1 infection in previously untreated patients with cirrhosis and patients with previous null response with or without cirrhosis (C-WORTHY): a randomised, open-label phase 2 trial.

BACKGROUND: There is a high medical need for an interferon-free, all-oral, short-duration therapy for hepatitis C virus (HCV) that is highly effective across diverse patient populations, including patients with cirrhosis or previous null response to pegylated interferon (peginterferon) plus ribavirin (PR-null responders). We aimed to assess the efficacy, safety, and effective treatment duration of grazoprevir (an HCV NS3/4A protease inhibitor) combined with elbasvir (an HCV NS5A inhibitor) with or without ribavirin in patients with HCV genotype 1 infection with baseline characteristics of poor response. METHODS: The C-WORTHY trial is a randomised, open-label phase 2 trial of grazoprevir plus elbasvir with or without ribavirin; here we report findings for two cohorts of previously untreated patients with cirrhosis (cohort 1) and those with previous PR-null response with or without cirrhosis (cohort 2) enrolled in part B of the study. Eligible patients were adults aged 18 years or older with chronic HCV genotype 1 infection and HCV RNA concentrations of 10 000 IU/mL or higher in peripheral blood. We randomly assigned patients to receive grazoprevir (100 mg daily) and elbasvir (50 mg daily) with or without ribavirin for 12 or 18 weeks. Randomisation was done centrally with an interactive voice response system; patients and study investigators were masked to treatment duration up to week 12 but not to treatment allocation. The primary endpoint was the proportion of patients achieving HCV RNA less than 25 IU/mL at 12 weeks after end of treatment (SVR12), assessed by COBAS TaqMan version 2.0. This study is registered with ClinicalTrials.gov, number NCT01717326. FINDINGS: We describe findings for 253 patients enrolled in cohort 1 (n=123) or cohort 2 (n=130). In cohort 1, we randomly assigned 60 patients to the 12-week regimen (31 with ribavirin and 29 with no ribavirin) and 63 to the 18-week regimen (32 with ribavirin and 31 with no ribavirin); in cohort 2, we randomly assigned 65 patients to the 12-week regimen (32 with ribavirin and 33 with no ribavirin) and 65 to the 18-week regimen (33 with ribavirin and 32 with no ribavirin. High SVR12 rates were achieved irrespective of the use of ribavirin or extension of the treatment duration from 12 to 18 weeks; SVR12 rates ranged from 90% (95% CI 74-98; 28/31; cohort 1, 12 weeks, ribavirin-containing) to 100% (95% CI 89-100; 33/33; cohort 2, 18 weeks, ribavirin-containing). Among patients treated for 12 weeks with grazoprevir plus elbasvir without ribavirin, 97% (95% CI 82-100, 28/29) of patients in cohort 1 and 91% (76-98, 30/33) of patients in cohort 2 achieved SVR12. Adverse events reported in more than 10% of patients were fatigue (66 patients, 26% [95% CI 21-32]), headache (58 patients, 23% [95% CI 18-29]), and asthenia (35 patients, 14% [95% CI 10-19]). INTERPRETATION: Treatment with grazoprevir plus elbasvir, both with and without ribavirin and for both 12 and 18 weeks' treatment duration, showed high rates of efficacy in previously untreated patients with cirrhosis and previous PR-null responders with and without cirrhosis. These results support the phase 3 development of grazoprevir plus elbasvir. FUNDING: Merck & Co, Inc.

Randomized controlled trial of danoprevir plus peginterferon alfa-2a and ribavirin in treatment-naïve patients with hepatitis C virus genotype 1 infection.

BACKGROUND & AIMS: The combination of a hepatitis C virus (HCV) protease inhibitor, peginterferon, and ribavirin is the standard of care for patients with HCV genotype 1 infection. We report the efficacy and safety of response-guided therapy with danoprevir (a potent second-generation protease inhibitor), peginterferon alfa-2a (40 KD), and ribavirin in these patients. METHODS: Treatment-naïve patients (N = 237) were randomly assigned to groups given 12 weeks of danoprevir (300 mg every 8 hours; 600 mg every 12 hours, and 900 mg every 12 hours) or placebo plus peginterferon alfa-2a and ribavirin, followed by peginterferon alfa-2a and ribavirin. Patients given danoprevir who had an extended rapid virologic response (eRVR4-20: HCV RNA <15 IU/mL during weeks 4-20) stopped therapy at week 24; those without an eRVR4-20 continued therapy to 48 weeks. Patients who were given placebo received 48 weeks of peginterferon alfa-2a and ribavirin. The primary efficacy end point was sustained virologic response (SVR: HCV RNA <15 IU/mL after 24 weeks without treatment). RESULTS: Rates of SVR were higher among patients given danoprevir 300 mg (68%), 600 mg (85%), and 900 mg (76%) than placebo (42%) (95% confidence interval: 26%-59%). Seventy-nine percent of patients given danoprevir 600 mg had an eRVR4-20; among these, 96% had an SVR. Serious adverse events were reported in 7% to 8% of patients given danoprevir and 19% given placebo. Four patients given danoprevir (1 patient in the 600-mg group and 3 in the 900-mg group) had reversible, grade 4 increases in alanine aminotransferase, which led to early discontinuation of the 900-mg arm of the study. CONCLUSIONS: The combination of danoprevir, peginterferon alfa-2a, and ribavirin leads to high rates of SVR in patients with HCV genotype 1 infection, but high doses of danoprevir can lead to grade 4 increases in alanine aminotransferase. Studies of lower doses of danoprevir with ritonavir, to reduce overall danoprevir exposure while maintaining potent antiviral activity, are underway; Clinicaltrials.gov number, NCT00963885.

Effects of ribavirin dose reduction vs erythropoietin for boceprevir-related anemia in patients with chronic hepatitis C virus genotype 1 infection--a randomized trial.

BACKGROUND & AIMS: Treatment of hepatitis C virus (HCV) infection with boceprevir, peginterferon, and ribavirin can lead to anemia, which has been managed by reducing ribavirin dose and/or erythropoietin therapy. We assessed the effects of these anemia management strategies on rates of sustained virologic response (SVR) and safety. METHODS: Patients (n = 687) received 4 weeks of peginterferon and ribavirin followed by 24 or 44 weeks of boceprevir (800 mg, 3 times each day) plus peginterferon and ribavirin. Patients who became anemic (levels of hemoglobin approximately ≤10 g/dL) during the study treatment period (n = 500) were assigned to groups that were managed by ribavirin dosage reduction (n = 249) or erythropoietin therapy (n = 251). RESULTS: Rates of SVR were comparable between patients whose anemia was managed by ribavirin dosage reduction (71.5%) vs erythropoietin therapy (70.9%), regardless of the timing of the first intervention to manage anemia or the magnitude of ribavirin dosage reduction. There was a threshold for the effect on rate of SVR: patients who received <50% of the total milligrams of ribavirin assigned by the protocol had a significantly lower rate of SVR (P < .0001) than those who received ≥50%. Among patients who did not develop anemia, the rate of SVR was 40.1%. Eleven thromboembolic adverse events were reported in 9 of 295 patients who received erythropoietin, compared with 1 of 392 patients who did not receive erythropoietin. CONCLUSIONS: Reduction of ribavirin dosage can be the primary approach for management of anemia in patients receiving peginterferon, ribavirin, and boceprevir for HCV infection. Reduction in ribavirin dosage throughout the course of triple therapy does not affect rates of SVR. However, it is important that the patient receives at least 50% of the total amount (milligrams) of ribavirin assigned by response-guided therapy. ClinicalTrials.gov number, NCT01023035.

Overall safety profile of boceprevir plus peginterferon alfa-2b and ribavirin in patients with chronic hepatitis C genotype 1: a combined analysis of 3 phase 2/3 clinical trials.

BACKGROUND & AIMS: Triple therapy with peginterferon/ribavirin (PR) plus an NS3 protease inhibitor has emerged as the standard-of-care for patients with chronic hepatitis C genotype-1. We provide a detailed safety analysis comparing PR to boceprevir plus PR (BOC/PR) across three phase 2/3 studies. METHODS: SPRINT-1 was an open-label phase 2 study in 595 treatment-naive patients. In the two phase 3 studies, 1500 patients (1097 treatment-naive, SPRINT-2; 403 treatment-failure, RESPOND-2) were randomized to receive PR alone, or one of two regimens where BOC was added to PR after a 4-wk PR lead-in. In this analysis, the respective BOC/PR and PR arms were combined for all three trials. The benefit of shortened duration of treatment using response-guided therapy (RGT) was also explored in the SPRINT-2 trial. RESULTS: Only two adverse events, anaemia and dysgeusia, occurred 20% more often with the BOC-containing regimens compared with PR. Nausea, diarrhoea and neutropenia were the only other common events with an incidence of at least 5% greater when BOC was added to the PR backbone. The proportions of patients reporting serious adverse events (AE), life-threatening AEs, and study drug discontinuation because of an AE were similar in the PR and BOC/PR arms. In treatment-naive patients, RGT generally did not result in a lower frequency of common AEs; however, RGT led to decreased exposure to all 3 study drugs and to a decrease in the mean duration of several clinically relevant AEs such as anaemia, neutropenia, fatigue and depression, as well as earlier normalization of haemoglobin and neutrophil counts. CONCLUSIONS: The safety profile of BOC combination therapy largely reflects the known profile of peginterferon and ribavirin, with incremental haematolgical effects and dysgeusia. Shorter treatment duration with RGT significantly reduced the duration of AEs.

Peginterferon α-2a plus ribavirin in Latino and Non-Latino Whites with HCV genotype 1: Histologic outcomes and tolerability from the LATINO Study.

OBJECTIVES: We sought to compare the histologic response, safety, and tolerability in Latino and non-Latino patients with hepatitis C virus (HCV) genotype 1 treated with peginterferon α-2a plus ribavirin (LATINO study). METHODS: LATINO was a prospective, open-label, multicenter study that enrolled 269 Latinos and 300 non-Latinos receiving peginterferon α-2a 180 µg/week and ribavirin 1,000/1,200 mg/day for 48 weeks. Liver biopsies were obtained within 18 months of baseline and at week 72. Improved or worsened liver fibrosis and necroinflammatory activity were assessed by the Ishak-modified histologic activity index scoring system. Efficacy and safety parameters were monitored during treatment and the 24-week follow-up period. RESULTS: The primary study results published elsewhere showed a higher sustained virologic response (SVR) rate among non-Latinos than Latinos (49% vs. 34%; P<0.001). Paired biopsy data were available for 157 Latinos and 201 non-Latinos. At baseline, more Latinos vs. non-Latinos had alanine aminotransferase (ALT) >3 × the upper limit of normal (20% vs. 18%) and cirrhosis (13% vs. 10%). Both groups experienced improvement in Ishak activity at week 72, although the improvement rates were higher in non-Latinos than Latinos (59% vs. 47%; P=0.03). For both groups, more patients with SVR compared with non-responders had improved Ishak fibrosis scores. In both groups, baseline Ishak activity score (P<0.0001 for both) was predictive of Ishak activity response. Additional predictors in Latinos were age (P=0.0023), body mass index (BMI) (P=0.068), baseline ALT quotient (P=0.031), and baseline Ishak fibrosis scores (P=0.021). There were no significant differences in steatosis changes between the two groups. Adverse events (AEs) and withdrawals due to AEs were more frequent in non-Latinos. CONCLUSIONS: Significant proportions of patients in both groups had histologic response to peginterferon α-2a plus ribavirin. However, histologic response was higher in non-Latinos than in Latinos regardless of virologic response. This study highlights the need for additional strategies to improve virologic response in Latinos.

Effect of peginterferon alfa-2a on liver histology in chronic hepatitis C: a meta-analysis of individual patient data.

Multicenter randomized trials have shown that once-weekly pegylated interferon (peginterferon) alfa-2a is more efficacious than conventional interferon alfa-2a (IFN) in patients with chronic hepatitis C. We performed a meta-analysis of 1,013 previously untreated patients (from 3 randomized trials) with pretreatment and post-treatment liver biopsies to assess the differences between peginterferon alfa-2a and IFN in terms of their effects on liver histology. Reported values were standardized mean differences (SMD) between patients receiving peginterferon alfa-2a and those receiving IFN (post-treatment value minus baseline value for each group). We used a random-effects model to quantify the average effect of peginterferon alfa-2a on liver histology. Peginterferon alfa-2a significantly reduced fibrosis compared with IFN (SMD, -0.14; 95% CI: -0.27, -0.01; P =.04). A reduction in fibrosis was observed among sustained virologic responders (SMD, -0.59; 95% CI: -0.89, -0.30; P <.0001) and patients with recurrent disease (SMD, -0.34; 95% CI: -0.54, -0.14; P =.0007), whereas no significant reduction was observed among nonresponders (SMD, -0.13; 95% CI: -0.32, 0.05; P =.15). Logistic regression analysis indicated that patients with sustained virologic responses (SVRs) had an odds ratio (OR) of 1.61 (95% CI: 1.14, 2.29) for reduction in fibrosis compared with patients without SVRs, whereas obese patients (body mass index [BMI] > 30 kg/m(2)) had an OR of 0.56 (95% CI: 0.35, 0.90) compared with normal-weight (BMI < 25 kg/m(2)) and overweight patients (BMI, 25-30 kg/m(2)). In conclusion, in patients with chronic hepatitis C with or without cirrhosis, peginterferon alfa-2a (relative to IFN) significantly reduced fibrosis. The beneficial effects of peginterferon on liver histology are closely related to virologic response.