Limited use of interleukin 28B in the setting of response-guided treatment with detailed on-treatment virological monitoring.

UNLABELLED: A single-nucleotide polymorphism upstream of the interleukin-28B (IL28B) gene is associated with pegylated interferon-alfa-induced viral clearance in hepatitis C virus (HCV) genotype 1 patients. Using a well-characterized cohort of patients randomized to standard versus response-guided therapy, we studied whether the favorable CC type allows shortening of treatment duration. Association with viral kinetics, sustained viral response (SVR), and predictors of response were also analyzed. In the original study, 696 patients were randomized to either standard or variable therapy of 24, 48, or 72 weeks according to first undetectable HCV RNA. Association between IL28B determined by genotyping rs12979860 and end of treatment response and SVR by treatment arm was tested; baseline predictors of response were analyzed using multiple logistic regression. A total of 454 patients were evaluated. The frequency of IL28B type was CC = 29%, CT = 53%, TT = 18%. CC type was strongly associated with rapid virological response (RVR) as well as higher rates of week 8 and week 12 response. CC type was associated with SVR in both arms. In patients with RVR, SVR was high and IL28B type was not associated with SVR. In RVR patients, there was no significant difference in SVR or relapse rates after 24 or 48 weeks by IL28B type. Among non-RVR patients, CC type was associated with SVR at a higher rate than CT/TT, both in standard and variable analysis. However, when week 8 and week 12 responders were considered separately, IL28B type was no longer predictive of SVR. Few CC patients remained viremic beyond week 8 to allow the analysis of relationships between IL28B type and extended treatment. CONCLUSION: In HCV-1 patients, the favorable CC type strongly predicted higher rates of on-treatment virological milestones and SVR. However, achievement of on-treatment virological milestones was the critical factor in determining outcome. IL28B type appeared to have limited potential for response-guided treatment strategies.

Inosine triphosphatase genetic variants are protective against anemia during antiviral therapy for HCV2/3 but do not decrease dose reductions of RBV or increase SVR.

UNLABELLED: Two functional variants in the inosine triphosphatase (ITPA) gene causing inosine triphosphatase (ITPase) deficiency protect against ribavirin (RBV)-induced hemolytic anemia and the need for RBV dose reduction in patients with genotype 1 hepatitis C virus (HCV). No data are available for genotype 2/3 HCV. We evaluated the association between the casual ITPA variants and on-treatment anemia in a well-characterized cohort of genotype 2/3 patients treated with variable-duration pegylated interferon alfa-2b (PEG-IFN-α2b) and RBV. Two hundred thirty-eight Caucasian patients were included in this retrospective study [185 (78%) with genotype 2 and 53 (22%) with genotype 3]. Patients were treated with PEG-IFN-α2b plus weight-based RBV (1000/1200 mg) for 12 (n = 109) or 24 weeks (n = 129). The ITPA polymorphisms rs1127354 and rs7270101 were genotyped, and an ITPase deficiency variable was defined that combined both ITPA variants according to their effect on ITPase activity. The primary endpoint was hemoglobin (Hb) reduction in week 4. We also considered Hb reduction over the course of therapy, the need for RBV dose modification, and the rate of sustained virological response (SVR). The ITPA variants were strongly and independently associated with protection from week 4 anemia (P = 10(-6) for rs1127354 and P = 10(-7) for rs7270101). Combining the variants into the ITPase deficiency variable increased the strength of association (P = 10(-11) ). ITPase deficiency protected against anemia throughout treatment. ITPase deficiency was associated with a delayed time to an Hb level < 10 g/dL (hazard ratio = 0.25, 95% confidence interval = 0.08-0.84, P = 0.025) but not with the rate of RBV dose modification (required per protocol at Hb < 9.5 g/dL). There was no association between the ITPA variants and SVR. CONCLUSION: Two ITPA variants were strongly associated with protection against treatment-related anemia in patients with genotype 2/3 HCV, but they did not decrease the need for RBV dose reduction or increase the rate of SVR.

An IL28B polymorphism determines treatment response of hepatitis C virus genotype 2 or 3 patients who do not achieve a rapid virologic response.

BACKGROUND & AIMS: Polymorphisms in the region of the interleukin (IL)-28B gene on chromosome 19 have been associated with peginterferon-alfa-induced clearance of genotype 1 hepatitis C virus (HCV); there are no data for patients with genotype 2 or 3 HCV. We evaluated the effects of IL-28B polymorphisms on response to treatment with peginterferon and ribavirin in a well-characterized cohort of genotype 2/3 patients. METHODS: DNA was analyzed from 268 patients (Caucasian: genotype 2, 213; genotype 3, 55). Patients were randomly assigned to groups that received standard duration (24 wk; n = 68) or variable durations of therapy. Patients who received variable durations (VD) and had a rapid virologic response (RVR) were treated for 12 weeks (VD12; n = 122); those without an RVR were treated for 24 weeks (VD24; n = 78). IL-28B genotypes (rs12979860) were analyzed for association with treatment response. RESULTS: The frequencies of the IL-28B genotypes were as follows: CC, 37%; CT, 48%; and TT, 15%; 82% of patients with the CC genotype achieved a sustained virologic response (SVR), compared with 75% with the CT and 58% with the TT genotypes (P = .0046). Differences between IL-28B genotypes were greatest among patients who failed to attain RVR (VD24 SVR rates: CC, 87%; CT, 67%; and TT, 29%; P = .0002). Among patients with RVRs (61%), the IL-28B genotype was not associated with SVR (>70% for all IL-28B genotypes). In a multivariable logistic regression model, IL-28B genotype predicted SVR (odds ratio, 1.76; 95% confidence interval, 1.16-2.7). CONCLUSIONS: An IL-28B polymorphism was associated with an SVR in patients infected with genotype 2/3 HCV who did not achieve a RVR. Analysis of IL-28B genotype might be used to guide treatment for these patients.

Determinants of relapse after a short (12 weeks) course of antiviral therapy and re-treatment efficacy of a prolonged course in patients with chronic hepatitis C virus genotype 2 or 3 infection.

UNLABELLED: In hepatitis C virus (HCV) genotypes 2 and 3 patients, the high rate of relapse after 12 to 16 weeks of antiviral therapy is the main concern for shortening treatment duration. This study was undertaken to delineate predictors of relapse after short treatment in patients with undetectable HCV RNA at treatment week 4 (RVR), and to report in RVR patients with relapse the sustained virological response (SVR) after a second 24-week course of therapy. RVR patients received pegylated interferon (Peg-IFN) alfa-2b (1.5 microg/kg) and ribavirin (1000-1200 mg/day) for 12 weeks; those who relapsed were re-treated with the same drug doses but for the extended standard duration of 24 weeks. Logistic regression analysis was applied to delineate predictors of relapse by using age, sex, route of transmission, body mass index (BMI), serum alanine aminotransferase (ALT), HCV genotypes, serum HCV RNA levels, and platelet counts as covariates. Of 718 patients with genotypes 2 and 3 who were started on therapy, 496 (69.1%) had undetectable HCV RNA at week 4. Of them, 409 patients (82.5%, CI 79.1-85.8) attained SVR, and 67 (14.1%, CI 10.4-16.5) relapsed. At regression analysis, only platelet count less than 140,000 mm(3) [odds ratio, 2.51; confidence interval (CI), 1.49-4.20] and BMI 30 or higher (odds ratio, 1.7; CI, 1.03-2.70) were independently associated with relapse. Forty-three of 67 patients with relapse agreed to be re-treated, and an SVR was achieved in 30 (70.0%) of them. CONCLUSION: We recommend 12 weeks course of therapy for patients with undetectable HCV RNA at treatment week 4, providing they present with no advanced fibrosis and low BMI.

IL28B CC-genotype association with HLA-DQB1*0301 allele increases the prediction of spontaneous HCV RNA clearance in thalassaemic HCV-infected patients.

BACKGROUND: A single nucleotide polymorphism (SNP), upstream of the IL28B gene has been recently associated with natural clearance of HCV. In a well-characterized cohort of patients with thalassaemia major exposed to the risk of acquiring HCV infection by blood transfusions, we aimed to replicate this finding and to evaluate whether combining the IL28B genotype and HLA class II alleles allow viral clearance to be accurately predicted. METHODS: Of 168 patients, 130 with complete clinical history were included in the analysis. According with their HCV antibodies status 13 were defined HCV resistant, and 117 infected. Infected patients were subdivided, giving 49 with self-limiting and 68 with ongoing infection. RESULTS: IL28B CC-genotype was observed in 32 patients with self-limiting and in 23 with ongoing infection (64% versus 34%; P=0.004). HLA DQB1*0301 allele was associated with viral clearance in 36 cases (73%; P<0.0001). Both DQB1*0301 and IL28B CC-genotype were found to be independent predictors of HCV clearance (OR=5.64, 95% CI 1.52-20.9 and OR=5.76, 95% CI 2.16-15.33, respectively). With the addition of DQB1*0301, the accuracy of the prediction increased from 63% to 69%. CONCLUSIONS: In addition to IL28B CC-genotype, HLA DQB1*0301 helps in predicting natural clearance of HCV after acute infection.