Baseline factors and early viral response (week 4) to antiviral therapy with peginterferon and ribavirin for predicting sustained virologic response in patients infected with hepatitis C virus genotype 1: a multicenter study

IFN-λ: A New Class of Interferon with Distinct Functions-Implications for Hepatitis C Virus Research

Pegylated interferon-α and ribavirin (PEG-IFN/RBV) is widely used to treat chronic hepatitis C virus infection with notorious adverse reactions since the broad expression of IFN-α receptors on all nucleated cells. Accordingly, a Type III IFN with restricted receptors distribution is much safer as an alternative for HCV therapy. In addition, single nucleotide polymorphisms (SNPs) near the human IFN-λ3 gene, IL-28B, correlate strongly with the ability to achieve a sustained virological response (SVR) to therapy with pegylated IFN-α plus ribavirin in patients infected with chronic hepatitis C. Furthermore, we also discuss the most recent findings: IFN-λ4 predicts treatment outcomes of HCV infection. In consideration of the apparent limitations of current HCV therapy, especially high failure rate and universal side effects, prediction of treatment outcomes prior to the initiation of treatment and developing new alternative drugs are two important goals in HCV research.

Baseline factors associated with treatment response in patients infected with hepatitis C virus 1b by stratification of IL28B polymorphisms

Although the single-nucleotide polymorphism (SNP) rs12979860 in the IL28B gene is a better predictor of sustained virological response to treatment of chronic hepatitis C (CHC) than other baseline factors, some CHC patients with the favorable C allele cannot achieve a sustained virological response when treated with peginterferon plus ribavirin. The aim of this study was to examine baseline factors as predictors of rapid virological response (RVR) and complete early virological response (cEVR) to peginterferon alfa-2a plus ribavirin treatment in Chinese CHC patients with hepatitis C virus (HCV) genotype 1b, with emphasis on the difference between the rs129860 CC and CT/TT genotypes. A total of 337 treatment-naïve patients participated in this study. All patients were treated with peginterferon alfa-2a plus ribavirin at standard dosage. Serum samples from all patients were collected at baseline, week 4, and week 12 for testing of laboratory parameters, and IL28B genotypes were determined. Multivariate analysis showed that among rs12979860 CC genotype patients, glucose level and aspartate amino transferase (AST) activity were inversely associated with RVR, while abnormal platelet count and allergy inversely associated with cEVR. Among rs12979860 CT genotype patients, age below 40 years and short infection duration were associated with RVR, while age below 40 years, short infection duration, high body mass index (BMI), and no history of allergies were associated with cEVR. The baseline factors associated with the response to CHC treatment may depend on the IL28B genotype. Refinement of the baseline predictors based on IL28B genotypes may be useful for management of HCV infection.

Baseline factors and very early viral response (week 1) for predicting sustained virological response in telaprevir-based triple combination therapy for Japanese genotype 1b chronic hepatitis C patients: a multicenter study

BACKGROUND

Genetic polymorphisms near Interleukin 28B (IL28B) (rs8099917) and a rapid virological response (RVR) have been reported as predictors for a sustained virological response (SVR) to telaprevir (TVR)-based triple combination therapy. However, the association between SVR and viral kinetics earlier than week 4 after initiation of therapy remains unclear. Thus, we evaluated the SVR prediction ability of baseline factors and reduced hepatitis C virus (HCV) RNA levels at week 1 after the initiation of TVR-based therapy in Japanese genotype-1b chronic hepatitis C (CHC) patients.

METHODS

A total of 156 Japanese CHC patients received a 24-week regimen of TVR-based therapy. Baseline factors and reduction in HCV RNA levels at weeks 1 and 4 after the initiation of therapy were analyzed for SVR prediction.

RESULTS

Multiple logistic regression analysis for SVR in TVR-based therapy identified the IL28B TT genotype, a reduction of ≥ 4.7 log10 IU/mL in HCV RNA levels at week 1, RVR, and treatment-naïve/relapse. Whereas the SVR rate was higher than 90 % regardless of the reduction in HCV RNA levels at week 1 in patients with the TT genotype, a reduction of ≥ 4.7 log10 IU/mL in HCV RNA levels at week 1 was the strongest predictor of SVR in patients with the non-TT genotype, as determined by multiple logistic regression analysis (P = 0.0043).

CONCLUSIONS

The IL28B TT genotype is the most important baseline factor for predicting SVR, and a ≥ 4.7 log10 IU/mL reduction in HCV RNA at week 1 is a useful very early on-treatment predictor of SVR, especially in the non-TT genotype.