ITPA genotype protects against anemia during peginterferon and ribavirin therapy but does not influence virological response.

UNLABELLED: On-treatment anemia is associated with higher sustained virological response (SVR) rates during peginterferon plus ribavirin (RBV) therapy. Inosine triphosphatase (ITPA) variants causing ITPase deficiency have been shown to protect against RBV-induced anemia. However, ITPase activity has not been associated with SVR. To study this discrepancy, we examined the relationships between ITPase activity, on-treatment anemia, SVR, and RBV levels in hepatitis C virus genotype 1 (HCV-1) patients from the CHARIOT study. ITPA genotype (rs7270101, rs1127354) was used to define ITPase activity in 546 patients. Plasma RBV levels were measured using high-performance liquid chromatography (HPLC). Relationships between ITPase activity, on-treatment hemoglobin (Hb) levels, RBV levels, and SVR were tested using regression modeling, survival analysis, and locally weighted scatterplot smoothing (LOWESS) plot analysis. Hb decline was independently associated with SVR (P<0.0001). ITPase deficiency was present in 35%. ITPase deficiency strongly protected against Hb decline (P<0.0001), but was not associated with SVR (P=0.28). The probability of SVR increased with lower nadir Hb for both wild-type and deficient ITPase activity, but the association curve shifted to describe a parallel relationship at higher Hb levels in patients with ITPase deficiency. In a subset (n=203), we tested the hypothesis that the association between Hb decline and SVR reflected RBV levels rather than actual Hb level. RBV levels were associated with on-treatment Hb decline and SVR, but not ITPase activity. In regression models, adjustment for RBV levels attenuated the association between Hb decline and SVR. CONCLUSION: ITPase deficiency protects against RBV-induced anemia, but is not associated with SVR. Our data suggest that the relationship between Hb decline and SVR is not mechanistic, but is linked to RBV levels.

Vitamin D level and sustained virologic response to interferon-based antiviral therapy in chronic hepatitis C: a systematic review and meta-analysis.

BACKGROUND & AIMS: The baseline 25-hydroxyvitamin D (25[OH]D) level has recently been reported to be an independent predictor of sustained virologic response (SVR) to treatment with pegylated interferon (PEG-IFN) plus ribavirin (RBV) for chronic hepatitis C virus (HCV) infection. However, studies have yielded inconsistent results. Thus, we conducted a systematic review and meta-analysis to clarify any association between baseline 25(OH)D level and SVR in HCV therapy. METHODS: Two reviewers searched four electronic databases (Medline, Embase, PubMed, and Cochrane trials register) and relevant international conference proceedings up to March 2014 for studies treating chronic HCV infection with PEG-IFN plus RBV where baseline 25(OH)D level was tested. Studies involving patients with HIV co-infection, previous liver transplantation or those receiving vitamin D supplementation were excluded. The mean baseline 25(OH)D level was compared between those who achieved and those who failed to achieve SVR. Pooled standard difference in mean 25(OH)D level, odds ratios (OR) and 95% confidence intervals (CI) were calculated with the Comprehensive Meta-Analysis software (version 2.0) using a random effects model. RESULTS: 11 studies comprising 2605 patients were included in the meta-analysis. There was no significant association between the baseline mean 25(OH)D level and SVR (OR 1.44, 95% CI 0.92-2.26; p=0.11), either in patients infected with genotypes 1/4/5 (OR 1.48, 95% CI 0.94-2.34; p=0.09) or genotypes 2/3 (OR 1.51, 95% CI 0.26-8.87; p=0.65). CONCLUSIONS: The baseline 25(OH)D level is not associated with SVR to PEG-IFN plus RBV therapy in chronic HCV infection, regardless of genotype. Any effect of vitamin D supplementation on SVR is yet to be definitively determined.

Vitamin D status does not predict sustained virologic response or fibrosis stage in chronic hepatitis C genotype 1 infection.

BACKGROUND & AIMS: The relationship between vitamin D status and response to antiviral therapy and liver histology in hepatitis C virus genotype 1 (HCV-1) infection remains unclear, with studies to date yielding inconsistent results and failing to use reference assay methodology. We therefore analyzed pre-treatment 25-hydroxyvitamin D [25(OH)D] level, using reference liquid chromatography-tandem mass spectrometry methodology, in a cohort of treatment-naïve patients with HCV-1 to evaluate the association between vitamin D status, virologic response, and liver histology. METHODS: 274 patients, with pre-treatment liver biopsy and up to 48 weeks of pegylated interferon alfa-2a plus ribavirin therapy, were tested for serum 25(OH)D level. Predictors of sustained virologic response (SVR), and variables associated with fibrosis stage, activity grade and 25(OH)D status were identified using multivariate analysis. RESULTS: Mean 25(OH)D level was 79.6 nmol/L, with a prevalence of 25(OH)D <75 nmol/L and <50 nmol/L of 48% and 16%, respectively. Season, race and geographic latitude were independent predictors of 25(OH)D status, while vitamin D deficiency was more prevalent in those with high activity grade (21% vs. 11%; p=0.03). Mean 25(OH)D level was lower (76.6 vs. 84.7 nmol/L; p=0.03) and 25(OH)D <75 nmol/L more prevalent (53% vs. 40%; p=0.03) in patients with an SVR, but no association between 25(OH)D status and SVR was found in multivariate analysis. Mean 25(OH)D level did not vary between fibrosis stage or activity grade. CONCLUSIONS: Baseline 25(OH)D level is not independently associated with SVR or fibrosis stage in HCV-1, but vitamin D deficiency is associated with high activity grade.

Virological response is associated with decline in hemoglobin concentration during pegylated interferon and ribavirin therapy in hepatitis C virus genotype 1.

UNLABELLED: Anemia may increase the likelihood of achieving a sustained virological response (SVR) during pegylated interferon and ribavirin treatment of hepatitis C virus (HCV) infection. To determine whether hemoglobin decline is associated with SVR, we retrospectively evaluated the CHARIOT study of 871 treatment-naïve HCV genotype 1 patients. Anemia (serum hemoglobin <100 g/L) occurred in 137 (16%) patients, of whom only 14 (10%) received erythropoietin. Hemoglobin decline >30g/L from baseline occurred in 76% of patients overall, including 526 patients who did not become anemic. Virological responses were higher in anemic patients compared with those who did not develop anemia (end of treatment, 80% versus 65%, P = 0.003; SVR, 61% versus 50%, P = 0.02); these differences remained significant when patients receiving erythropoietin were excluded from analysis. SVR was also higher in patients with hemoglobin decline >30 g/L compared with patients without a similar decline. In multiple logistic regression analyses with treatment group and baseline characteristics, the odds ratio for SVR was 1.97 (95% confidence interval, 1.08-3.62) for anemia and 2.17 (95% confidence interval, 1.31-3.62) for hemoglobin decline >30 g/L. Patients who first developed a hemoglobin decline >30 g/L during weeks 5-12 and 13-48 were more likely to achieve SVR than those who first developed such changes in weeks 0-4 or who never experienced them. CONCLUSION: Patients with HCV genotype 1 infection who develop anemia or experience a hemoglobin decline >30 g/L during weeks 5-48 of therapy achieve higher virological responses to pegylated interferon and ribavirin therapy that are unrelated to erythropoietin use.

Safety of peginterferon alfa-2a plus ribavirin in a large multinational cohort of chronic hepatitis C patients.

BACKGROUND & AIMS: Peginterferon plus ribavirin has been the standard of care for chronic hepatitis C for a decade and an essential component of combination regimens for this disease. This large multinational open-label study aimed to better define the incidence of serious adverse events (SAEs) and non-serious adverse events of special interest in patients receiving peginterferon alfa-2a/ribavirin. METHODS: Patients were assigned at the investigator's discretion to 24- or 48-week treatment with peginterferon alfa-2a 180 µg/week and ribavirin 800 mg/day or 1000/1200 mg/day. All AEs, defined as SAEs and non-SAEs of special interest, were recorded during treatment and for 12 weeks thereafter. Non-SAEs of special interest included those leading to dose reduction/discontinuation, neutropenia, thrombocytopenia, anaemia, ALT elevations leading to dose modification and unknown/unexpected AEs. RESULTS: Of 1675 and 7178 patients assigned to 24 and 48 weeks of treatment, respectively, 87.6 and 68.3% completed therapy, whereas 6.4 and 10.3% prematurely stopped peginterferon alfa-2a treatment because of AEs. Among patients assigned to 24 and 48 weeks, 37.4 and 46.9%, respectively, reported any AE (SAE or non-SAE of special interest); 4.2 and 6.6% reported SAEs and 35.2 and 44.0% reported non-SAEs of special interest. Female gender, increasing age and cirrhosis were significantly associated with dose reductions of either drug. Increasing age (and female gender in the case of ribavirin) was significantly associated with treatment discontinuation. CONCLUSION: This study confirmed the safety and tolerability profile of peginterferon alfa-2a/ribavirin and identified patient subgroups at higher risk of dose reductions and discontinuations, thus allowing optimum management of AEs.

Oral combination therapy with a nucleoside polymerase inhibitor (RG7128) and danoprevir for chronic hepatitis C genotype 1 infection (INFORM-1): a randomised, double-blind, placebo-controlled, dose-escalation trial.

BACKGROUND: Present interferon-based standard of care treatment for chronic hepatitis C virus (HCV) infection is limited by both efficacy and tolerability. We assessed the safety, tolerability, and antiviral activity of an all-oral combination treatment with two experimental anti-HCV drugs-RG7128, a nucleoside polymerase inhibitor; and danoprevir, an NS3/4A protease inhibitor-in patients with chronic HCV infection. METHODS: Patients from six centres in New Zealand and Australia who were chronically infected with HCV genotype 1 received up to 13 days oral combination treatment with RG7128 (500 mg or 1000 mg twice daily) and danoprevir (100 mg or 200 mg every 8 h or 600 mg or 900 mg twice daily) or placebo. Eligible patients were sequentially enrolled into one of seven treatment cohorts and were randomly assigned by interactive voice or web response system to either active treatment or placebo. Patients were separately randomly assigned within each cohort with a block size that reflected the number of patients in the cohort and the ratio of treatment to placebo. The random allocation schedule was computer generated. Dose escalation was started in HCV treatment-naive patients; standard of care treatment-experienced patients, including previous null responders, were enrolled in higher-dose danoprevir cohorts. Investigators, personnel at the study centre, and patients were masked to treatment allocation. However, the pharmacist who prepared the doses, personnel involved in pharmacokinetic sample analyses, statisticians who prepared data summaries, and the clinical pharmacologists who reviewed the data before deciding to initiate dosing in the next cohort were not masked to treatment allocation. The primary outcome was change in HCV RNA concentration from baseline to day 14 in patients who received 13 days of combination treatment. All patients who completed treatment with the study drugs were included in the analyses. This study is registered with ClinicalTrials.gov, NCT00801255. FINDINGS: 88 patients were randomly assigned to a study drug treatment regimen (n=74 over seven treatment groups; 73 received at least one dose of study drug) or to placebo (n=14, all of whom received at least one dose). The median change in HCV RNA concentration from baseline to day 14 ranged from -3·7 to -5·2 log(10) IU/mL in the cohorts that received 13 days of combination treatment. At the highest combination doses tested (1000 mg RG7128 and 900 mg danoprevir twice daily), the median change in HCV RNA concentration from baseline to day 14 was -5·1 log(10) IU/mL (IQR -5·6 to -4·7) in treatment-naive patients and -4·9 log(10) IU/mL in previous standard of care null responders (-5·2 to -4·5) compared with an increase of 0·1 log(10) IU/mL in the placebo group. The combination of RG7128 and danoprevir was well tolerated with no treatment-related serious or severe adverse events, no grade 3 or 4 changes in laboratory parameters, and no safety-related treatment discontinuations. INTERPRETATION: This oral combination of a nucleoside analogue polymerase inhibitor and protease inhibitor holds promise as an interferon-free treatment for chronic HCV. FUNDING: Roche Palo Alto.

Efficacy and safety of peginterferon alfa-2a (40KD) plus ribavirin in hepatitis C patients with advanced fibrosis and cirrhosis.

UNLABELLED: The objective of this study is to determine the efficacy and safety of peginterferon alfa-2a (40 KD)/ribavirin in patients with advanced fibrosis. Data from 341 genotype 1/4 patients (99 with bridging fibrosis/cirrhosis) treated for 48 weeks and 1547 genotype 2/3 patients (380 with bridging fibrosis/cirrhosis) treated for 16 or 24 weeks enrolled in three randomized international studies were analyzed. Sustained virological response (SVR) rates decreased progressively from 60% in genotype 1/4 patients without advanced fibrosis to 51% in those with bridging fibrosis and 33% in those with cirrhosis (trend test P = 0.0028); and from 76% to 61% and 57%, respectively, in genotype 2/3 patients treated for 24 weeks (trend test P < 0.0001). Irrespective of genotype, patients without advanced fibrosis were more likely to have an earlier response to treatment that was associated with higher SVR rates and lower relapse rates during untreated follow-up. Among patients with or without a diagnosis of advanced fibrosis, rates of SVR and relapse were similar for patients with similar responses in the first 12 weeks. CONCLUSION: Compared with patients with less severe disease, SVR rates are significantly lower in patients with advanced fibrosis. However, irrespective of genotype and degree of fibrosis, the time to become hepatitis C virus (HCV) RNA undetectable was the strongest predictor of SVR.

Low virological response and high relapse rates in hepatitis C genotype 1 patients with advanced fibrosis despite adequate therapeutic dosing.

BACKGROUND & AIMS: The impact of fibrosis stage on chronic hepatitis C virus (HCV) treatment response was explored in CHARIOT, a study of high dose peginterferon alfa-2a (PEG-IFNalpha-2a) induction therapy in treatment naïve genotype 1 infection. METHODS: Eight hundred and ninety-six patients were randomised 1:1 to 360 microg (n=448) or 180 microg (n=448) PEG-IFNalpha-2a weekly with RBV 1000-1200 mg/day for 12 weeks followed by 36 weeks of 180 microg PEG-IFNalpha-2a weekly plus RBV 1000-1200 mg/day. Virological responses were assessed at week 4, 8, 12, 24, 48 (end of therapy), and 24 weeks following therapy (sustained virological response, SVR). As previously reported, there was no significant difference in SVR in the induction (53%) and standard (50%) arms, therefore the pooled study population was used for analysis of SVR and relapse. RESULTS: A marked step-wise decline in SVR was evident by fibrosis stage: F0 (70%); F1 (60%); F2 (51%); F3 (31%); F4 (10%) (p<0.0001). Early virological responses were lower among F3/4 patients, including rapid virological response (RVR) (21% vs. 34% for F3/4 and F0-2, respectively) (p=0.0072), and the RVR positive predictive value was also lower (63% vs. 80%). Virological relapse rates were similar in early disease stages (F0, 16%; F1, 23%; F2, 26%), but increased markedly in advanced fibrosis (F3, 50%; F4, 80%) (p<0.0001). Cumulative PEG-IFNalpha-2a and ribavirin doses were similar among patients with F3/4 and F0-2 within treatment arms through week 4, 8, 12, and week 24. CONCLUSIONS: Low virological response in hepatitis C genotype 1 patients with advanced fibrosis is not explained by inadequate cumulative PEG-IFN and ribavirin doses.

Impact of high-dose peginterferon alfa-2A on virological response rates in patients with hepatitis C genotype 1: a randomized controlled trial.

UNLABELLED: This study tested the hypothesis that high-dose peginterferon alfa-2a (PEG-IFNalpha-2a) for the first 12 weeks would increase early and sustained virological response (SVR) rates in patients with chronic hepatitis C genotype 1. Eight hundred ninety-six patients were randomized 1:1 to 360 microg (n = 448) or 180 microg (n = 448) PEG-IFNalpha-2a weekly plus ribavirin at 1000-1200 mg/day for 12 weeks, followed by 36 weeks of 180 microg PEG-IFNalpha-2a weekly plus ribavirin at 1000-1200 mg/day with 871 patients evaluable for the intention-to-treat analysis. Virological responses were assessed by TaqMan (limit of detection 15 IU/mL) at week 4, 8, 12, 24, 48 (end of therapy), and 24 weeks following therapy (SVR). Undetectable hepatitis C virus RNA rates were significantly higher among patients receiving high-dose induction therapy at week 4 (36% versus 26%, P < 0.005), week 8 (61% versus 50%, P < 0.005), and week 12 (74% versus 62%, P < 0.005). However, SVR was not significantly different between patients receiving high-dose (53%) and standard (50%) therapy. Significant baseline prognostic factors for SVR included age, sex, race, histological stage, and viral load. SVR was considerably higher among patients with no or minimal fibrosis (64% and 60%, respectively) compared to those with severe fibrosis/cirrhosis (28% and 24%, respectively). The frequency of serious adverse events and drug discontinuations were similar in both groups, whereas PEG-IFN dose modification, weight and appetite reduction, and grade IV neutropenia were significantly higher in the induction arm. CONCLUSION: Induction dosing with 360 microg/week PEG-IFNalpha-2a for 12 weeks was well tolerated and enhanced early virological response but not SVR rates. The high SVR rates in patients with minimal fibrosis highlight the benefit of early treatment in patients with hepatitis C virus genotype 1.

Safety profile of standard- vs. high-dose peginterferon alfa-2a plus standard-dose ribavirin in HCV genotype 1/4 patients: pooled analysis from 5 randomized studies.

OBJECTIVE: This analysis examines the safety profile of standard- versus high-dose peginterferon alfa-2a. METHODS: Data were pooled from five trials including HCV genotype 1- or 4-infected naive and treatment-experienced patients (n = 2,940). Patients were randomized to receive peginterferon alfa-2a at 180 µg/week (standard-dose; n = 1,672) or 360 µg/week (high-dose; n = 1,268) plus ribavirin 1,000/1,200 mg/day for 12 weeks; after 12 weeks, all received standard dose. This safety analysis was restricted to the first 12 weeks. RESULTS: In standard and high-dose groups, similar frequencies of serious adverse events (SAEs, 3.2 and 4.2%, respectively) and treatment discontinuations for safety reasons (2.8 and 2.9%) were reported. More patients reported weight decrease as an adverse event (AE) in the 360 µg/week group (7.7 vs. 3.3%). Significant (p < 0.05) independent predictors for discontinuation due to safety were older age, male gender, lower albumin and low neutrophil count, but not the starting dose of peginterferon alfa-2a. Although more laboratory abnormalities were reported in patients receiving high-dose peginterferon alfa-2a, this was not reflected in AEs or discontinuations, suggesting these are adequately managed by dose modification. CONCLUSIONS: High-dose peginterferon alfa-2a for 12 weeks does not significantly increase the incidence of SAEs or discontinuations for safety reasons, beyond that of a standard dose regimen.