Interferon-gamma with peginterferon alpha-2a and ribavirin in nonresponder patients with chronic hepatitis C (ANRS HC16 GAMMATRI).

BACKGROUND AND AIM: Interferon-gamma-1b (IFN-γ-1b) improves alpha interferon (IFN-α) inhibition of hepatitis C virus (HCV) replication in replicon system. We described virological response after addition of IFN-γ to a combination of ribavirin/peginterferon (PEG-IFN)-α-2a or α-2b. METHODS: In this non-comparative, multicenter trial, patients chronically infected by HCV who were nonresponders to a previous treatment by PEG-IFN and ribavirin were restarted on a regimen of PEG-IFN-α-2a (180 µg/week) + ribavirin (1000-1200 mg/day) for 16 weeks. If HCV-RNA decreased less than 2 log(10) copies/mL (nonresponders), and if PEG-IFN-α-2a and ribavirin dosages were unchanged while tolerance was good, IFNγ-1b (100 µg three times per week) was added for the last 32 weeks of treatment. Virological response was evaluated at week 28 (12 weeks after initiation of IFN-γ-1b). RESULTS: Among the 48 patients started on dual therapy, 23 patients (47%) were nonresponders at week 12 and received IFN-γ-1b from week 16 onward. Their mean HCV-RNA (log(10) IU/mL) was 6.83 at baseline, 5.81 at week 12, and 5.63 at week 28. No patient reached undetectable HCV-RNA at week 28 (upper bound of 95% confidence interval: 14.8%); none had a decrease > 1 log(10) IU/mL. One case of grade 4 neutropenia was reported. CONCLUSION: Among the strictly selected nonresponders, IFN-γ-1b (at a dosage of 100 µg thrice a week) in combination with PEG-IFN-α-2a and ribavirin failed to show virological efficacy.

High-dose pegylated interferon-α and ribavirin in nonresponder hepatitis C patients and relationship with IL-28B genotype (SYREN trial).

BACKGROUND & AIMS: In patients with chronic hepatitis C who failed to respond to standard therapy, high-dose pegylated interferon (IFN)-α and/or ribavirin could induce a stronger antiviral response and prevent treatment failure and HCV resistance when combined with direct-acting antivirals. The influence of genetic determinants in this context remains unknown. METHODS: Eighty-three patients infected with HCV genotype 1 who were nonresponsive to standard therapy received pegylated IFN-α2a (360 µg once per week or 180 µg twice per week) with ribavirin (1.0-1.2 or 1.2-1.6 g/d) for up to 72 weeks. Virological responses were assessed at different time points, and the influence of the IL-28B genotype was studied. RESULTS: At weeks 12 and 24, respectively, 47 (56.6%) and 50 (60.2%) patients achieved a ≥2-Log10 decrease of HCV RNA levels; 8 (9.6%) and 21 (25.3%) patients had undetectable HCV RNA after 12 and 24 weeks of treatment, respectively. Patients with a CT IL-28B genotype responded significantly better and earlier than those with a TT genotype. In multivariate analysis, the IL-28B genotype was an independent predictor of the virological responses at weeks 4, 12, and 24. CONCLUSIONS: High-dose pegylated IFN-α with standard or high doses of ribavirin induces a potent antiviral response in a substantial number of patients who did not respond to standard therapy. The IL-28B genotype is an independent predictor of the antiviral response. High-dose pegylated IFN-α in combination with ribavirin and protease inhibitors appears as an attractive option for future study in this population.

Neutralizing antibodies to interferon-α and circulating interferon in patients with chronic hepatitis C non-responding to pegylated interferon plus ribavirin re-treated by pegylated interferon-α-2a and ribavirin (ANRS HC16 GAMMATRI substudy).

A lack of antiviral response in patients with chronic hepatitis C treated with pegylated (PEG)-interferon (IFN)-α-2a + ribavirin (RIBA) may be explained by neutralizing antibodies to IFN-α-2a. The aim of this study was to assess neutralizing antibodies to IFN-α-2a and IFN levels in non-responder patients who were re-treated by PEG IFN-α-2a and RIBA for 12 weeks. Non-responders to a first-line treatment of PEG IFN-α-2a + RIBA were included for treatment with PEG IFN-α-2a (180 µg/week) + RIBA (1,000 mg/day if <75 kg, 1,200 mg otherwise) for 48 weeks. HCV RNA was measured at week 12. IFN levels and neutralizing antibodies to IFN-α-2a were measured retrospectively on stored sera at baseline and weeks 4 and 12, using a quantitative sandwich ELISA for neutralizing antibodies to IFN-α-2a. Twenty-three patients were non-responders and 19 patients were responders at week 12 of the initial phase of the second-line treatment. Non-responders and responders did not differ statistically: baseline age (median age 47 vs. 50 years), HCV RNA (median 6.8 vs. 6.4 log(10) copies/ml), gender (70% vs. 73% males), genotype (genotype 1: 91% vs. 80%). The median IFN-α-2a levels (pg/ml) at weeks 0, 4, and 12 (interquartile range) did not differ between the 19 responders to initial phase of second-line treatment and the 23 non-responders: <3.3 (<3.3-371.4), 1457.3 (106.8-3284.8), and 1,652 (90.8-5,000); 84.5 (3.3-277.4), 1407.4 (120.2-2443.4), and 1620.1 (120.2-2287.1), respectively. Among non-selected consecutive non-responder patients, re-treatment with PEG IFN-α-2a + RIBA is associated with virological response regardless of the presence of antibody-mediated resistance to conventional IFN treatment.

Effect of ribavirin in genotype 1 patients with hepatitis C responding to pegylated interferon alfa-2a plus ribavirin.

BACKGROUND & AIMS: Pegylated interferon alfa-ribavirin combination is the standard treatment for chronic hepatitis C, but the mechanisms by which ribavirin enhances the rate of sustained hepatitis C virus (HCV) eradication remain unknown. We aimed to investigate the role of ribavirin in HCV clearance during therapy and to evaluate the consequences of ribavirin discontinuation in patients infected with genotype 1 hepatitis C who cleared HCV RNA at week 24. METHODS: A total of 516 patients were treated with pegylated interferon alfa-2a, 180 microg/wk, plus ribavirin, 800 mg/day. Seventy percent were RNA negative at week 24. They were randomized to continue with the combination or receive pegylated interferon alone. RESULTS: Responders at week 24 who stopped ribavirin had a significantly higher rate of breakthroughs during, and relapses after, therapy (sustained virologic response, 52.8% vs 68.2%; P = .004), but their side-effect profile and quality of life tended to improve. Multiple logistic regression analysis in the pegylated interferon alfa monotherapy group allowed identification of responders at week 24 who could stop ribavirin without losing their chance of a sustained virologic response, based on baseline viral load and age. Forty-eight weeks of ribavirin may not be needed when HCV RNA is undetectable at week 2. CONCLUSIONS: We made 3 conclusions from this study. First, ribavirin primarily acts by sustaining the virologic response to pegylated interferon alfa; second, ribavirin must be administered for the full treatment duration in most genotype 1-infected patients who respond; third, baseline parameters may help identify patients who could discontinue ribavirin or reduce the dose without losing their chance of success.