Interferon-based treatment of chronic hepatitis C

The treatment of patients with chronic hepatitis C has rapidly evolved in the past 10 years centered on the use of interferon alpha 2 as an antiviral and immunomodulatory agent against hepatitis C virus. Firstly used as a monotherapy associated with a deceiving long-term efficacy, interferon alpha was then combined with ribavirin, a nucleoside analog with large antiviral properties. Combination of both drugs dramatically improved the efficacy of treatment with 50% of patients reaching a sustained viral response, characterized by the final eradication of the virus from the infected individual. Surprisingly, this synergistic effect remains greatly unexplained. The third step consisted in the use of pegylated interferon in order to adapt its pharmacokinetics and to allow a better efficacy with a more tolerable dosing schedule: once weekly subcutaneous injection instead of thrice weekly. Pegylated interferon combined with ribavirin during 24-48 weeks of treatment is the current standard of care with nearly 60% of sustained virologic response, overall. Development of new forms of interferon alpha are on the way with promising preliminary results.     

Agranulocytosis during treatment of chronic hepatitis C complicated by hyperthyreosis. Case reports

Agranulocytosis is a life-threatening disorder characterised by a greatly decreased number of circulating neutrophils below 500/μL. This article presents two cases of agranulocytosis in patients treated with pegylated interferon and ribavirin due to chronic hepatitis C. Interferon induced hyperthyroidism, which required the use of a tyreostatic. Anti-thyroid drugs (ATD) used to treat hyperthyroidism can cause agranulocytosis. The synergistic reaction of ATD and interferon on bone marrow cannot be excluded.     

LecT-Hepa facilitates estimating treatment outcome during interferon therapy in chronic hepatitis C patients

Background

A combination treatment of interferon and ribavirin is the standard and the commonly used treatment for chronic hepatitis C (CHC). Developing noninvasive tests like serum indicators that can predict treatment outcome at an early stage of therapy is beneficial for individualized treatment and management of CHC. A glyco-indicator based on the glyco-alteration of serum α1-acid glycoprotein, LecT-Hepa, was discovered by glycomics technologies as a robust indicator of liver fibrosis. Here, we investigated the clinical utility of LecT-Hepa for evaluation of treatment outcome.

Results

Firstly, ninety-seven patients with CHC were used for comparison of LecT-Hepa in serum and plasma. We found no significant difference in the concentrations of LecT-Hepa in serum and plasma. And then, 213 serum specimens from 45 patients who received 48 weeks of treatment with interferon and ribavirin were followed up for 96 weeks, and were used for evaluation of the role of LecT-Hepa. We found that LecT-Hepa might reflect the change in fibrosis regression during the treatment process. Moreover, the change of LecT-Hepa at the first 12 weeks of treatment could already predict the antiviral treatment response, which was more superior to FIB-4 index and aspartate aminotransferase-to-platelet ratio index (APRI) in this study.

Conclusions

These results provide a new perspective that serum glycoprotein could be used as a joint diagnosis indicator for estimation treatment outcome of viral hepatitis at earlier stage of therapy.

Electronic supplementary material

The online version of this article (doi:10.1186/1559-0275-11-44) contains supplementary material, which is available to authorized users.     

New interferons in the treatment of chronic hepatitis C

The current standard therapy for chronic HCV infection is a combination of pegylated-interferon (PEG-IFN) and weight-based ribavirin, administered for 24-48 weeks, according to the viral genotype. Although the weekly administration of pegylated interferons provides superior antiviral efficacy over standard interferon alpha, the rate of sustained virological response rarely overpasses 50% in patients infected with HCV genotypes 1 and 4. Consequently, multiple clinical trials with congeners of interferon (consensus interferon, interferon lambda, albinterferon, and controlled-release interferons) are ongoing. Their main advantages consist in maintenance of viral suppression across a longer dosing interval, avoidance of interdose trough and reduced dosing frequencies (twice or even once per month compared to once per week for the actual PEG-IFNs). Along with these superior pharmacokinetic properties, new interferons are expected to have improved side-effect profiles and better tolerability compared with the currently available formulations, providing an option for otherwise difficult to treat, challenging populations. New interferon formulation can be incorporated into future combination with direct acting antivirals, in order to maintain viral suppression over longer periods and minimize the development of viral resistance.     

慢性丙型肝炎个体化治疗研究进展

丙型肝炎是由丙型肝炎病毒（HCV）引起的急、慢性传染病。丙型肝炎流行广泛,慢性化率高达50％～85％,并可转化为肝硬化和肝细胞肝癌。目前慢性丙型肝炎（CHC ）的标准治疗方案为聚乙二醇干扰素联合利巴韦林,但约50％的HCV 1型感染者不能获得持续病毒学应答。研究发现,HCV基因型、病毒载量,以及宿主的性别、年龄、乙醇摄入量、肝纤维化程度、合并感染、基因多态性等因素可影响治疗效果。其中,HCV病毒载量、HCV基因型及宿主基因多态性是预测持续病毒学应答的重要因素,可用于制订个体化治疗方案。     

Pathogenesis and treatment of autoimmune hepatitis and chronic viral hepatitis B and C.

Immune mechanisms play a role in autoimmune hepatitis which is considered as "idiopathic" inflammatory liver disease of unknown etiology. However, even chronic viral hepatitis B and C have also features suggesting the importance of immunopathogenesis in their development. This paper discusses the major genetical and immunological factors in the above-mentioned chronic liver diseases and briefly summarizes their therapeutic modalities.     

Treatment of chronic hepatitis C

Chronic hepatitis C entails a life-long risk of developing cirrhosis and hepatocellular carcinoma and eradication of the hepatitis C virus (HCV) is the only realistic approach for lowering the risk of disease progression. Treatment is indicated for patients with high transaminases and histologic signs of chronic hepatitis: 6-12 month therapy with 3-6MU interferon alfa thrice weekly combined with 1-1.2 grams ribavirin yielded up to 30% sustained virological responses (SVR). SVR raised up to 50% with pegylated interferons combined with ribavirin. Favourable predictors of response to the former treatment are genotype 2 or 3, less than 2 million copies of HCV, no or portal fibrosis at biopsy, age less than 40 yr and female gender. The same was true for the latter treatment, however, with body weight less than 82 kg replacing female gender. Six month treatment is enough for treating genotype 2 or 3 patients whereas 12-month therapy is indicated for the more resistant patients with genotype 1 or 4.98% cure of community-acquired acute hepatitis C was achieved with early treatment with daily doses of 5MU interferon, compared to a calculated 30% virus clearance occurring in untreated patients. Cost-effective stopping rules based upon early clearance of serum HCV-RNA, are under investigation. A cut-off equal or more than 2 log decrease in serum HCV-RNA at week 12, has 97% negative predictive value and 60% positive predictive value. Treatment could be optimized also by retreatment with combination therapy of relapsers and non-responders to monotherapy, with SVR rates of 50% and 25%, respectively. Difficult-to-treat patients include patients who have high genotype 1 and 4 viremia or coinfection with HIV or hepatitis B virus as well as patients who carry an organ graft. Extended treatment of virological non responders with pegylated interferons might slow down progression of hepatic fibrosis and prevent hepatocellular carcinoma.     

Temporal variations in the hepatitis C virus intrahost population during chronic infection

The intrahost evolution of hepatitis C virus (HCV) holds keys to understanding mechanisms responsible for the establishment of chronic infections and to development of a vaccine and therapeutics. In this study, intrahost variants of two variable HCV genomic regions, HVR1 and NS5A, were sequenced from four treatment-naïve chronically infected patients who were followed up from the acute stage of infection for 9 to 18 years. Median-joining network analysis indicated that the majority of the HCV intrahost variants were observed only at certain time points, but some variants were detectable at more than one time point. In all patients, these variants were found organized into communities or subpopulations. We hypothesize that HCV intrahost evolution is defined by two processes: incremental changes within communities through random mutation and alternations between coexisting communities. The HCV population was observed to incrementally evolve within a single community during approximately the first 3 years of infection, followed by dispersion into several subpopulations. Two patients demonstrated this pattern of dispersion for the rest of the observation period, while HCV variants in the other two patients converged into another single subpopulation after ∼9 to 12 years of dispersion. The final subpopulation in these two patients was under purifying selection. Intrahost HCV evolution in all four patients was characterized by a consistent increase in negative selection over time, suggesting the increasing HCV adaptation to the host late in infection. The data suggest specific staging of HCV intrahost evolution.     

Progression of fibrosis during chronic hepatitis C is associated with rapid virus evolution

Hepatic fibrosis is the primary mediator of disease due to chronic infection with hepatitis C virus (HCV). HCV exists as a quasispecies in each infected individual, and longitudinal viral sequence changes may reveal viral dynamics and the selection pressures applied by the host immune system. Thus, we hypothesized that patterns of sequence change might reveal the immunopathogenesis of fibrosis progression. We tested this hypothesis by studying individuals enrolled in a prospective study of chronic HCV-related hepatic fibrosis with little or no fibrosis at first biopsy (stage 0 or 1) and a second planned liver biopsy sample obtained 4 years later. Serum was obtained from five individuals with fast progression (FP; defined as a >2-stage change between visits) and 10 carefully matched individuals with slow progression (SP; defined as a <2-stage change between visits). We sequenced multiple cloned hemigenomic cDNAs from each person spanning six genes (core through NS3). Phylogenetic analysis revealed temporal shifts in phylogenetic clustering over time, suggesting frequent quasispecies replacement rather than simple diversification. In addition, mixed infections were detected in three subjects, with coexistence in two subjects (one FP, one SP) of subtypes 1a and 1b throughout the 4-year biopsy interval. Subjects with FP had a higher rate of evolution than subjects with SP, with a preponderance of synonymous changes, suggesting purifying selection, except in hypervariable region 1, where positive selection pressure is frequently detected. Thus, in a small but carefully matched cohort we found evidence for rapid neutral evolution of HCV in persons with rapid progression of hepatic fibrosis, suggesting higher turnover of infected cells.     

Therapy for chronic hepatitis C.

BACKGROUND/AIMS: in Hungary, over the past 5 years more than 900 patients with chronic hepatitis C have been examined for treatment with interferon at 16 major hepatology centres, using unified diagnostic and therapeutical criteria. Authors give an account of their experiences on the clinical features of patients with chronic hepatitis C and report the results of the interferon therapy. METHODS: a total of 993 patients--virtually the entire Hungarian hepatitis C patient population who had been referred for interferon treatment--were included in the program. Actually, the sustained efficacy of the therapy was evaluated in 724 cases. Treatment protocols (dose of interferon and duration of therapy) have changed with time from a weekly dose of 3x3 MU IFN for 6 months in the first period, to 3x3-5 MU for 12 months in the second period, and finally in the third period a combination therapy with ribavirin has also been introduced. RESULTS: in the first period, the end-of-treatment response (ETR) was 35%, sustained response (SR) 13%, the second phase schedule resulted in 42% ETR and 22% SR, while in the third period, ETR was 49% and SR 36%, respectively. Fibrosis in histology and baseline pretreatment HCV-RNA level appeared as predictors of response. The duration of treatment and the total dose of interferon exerted a moderate effect on therapeutic efficacy. Neither age nor gender influenced the outcome. CONCLUSIONS: our results-obtained in a Central East European country-are in accordance with findings of suboptimal efficacy of traditional interferon monotherapy for chronic hepatitis C reported in the West, and suggest the benefit of the combination treatment of interferon with ribavirin.     

Cost effectiveness of fibrosis assessment prior to treatment for chronic hepatitis C patients

Background and Aims

Chronic hepatitis C (HCV) is a liver disease affecting over 3 million Americans. Liver biopsy is the gold standard for assessing liver fibrosis and is used as a benchmark for initiating treatment, though it is expensive and carries risks of complications. FibroTest is a non-invasive biomarker assay for fibrosis, proposed as a screening alternative to biopsy.

Methods

We assessed the cost-effectiveness of FibroTest and liver biopsy used alone or sequentially for six strategies followed by treatment of eligible U.S. patients: FibroTest only; FibroTest with liver biopsy for ambiguous results; FibroTest followed by biopsy to rule in; or to rule out significant fibrosis; biopsy only (recommended practice); and treatment without screening. We developed a Markov model of chronic HCV that tracks fibrosis progression. Outcomes were expressed as expected lifetime costs (2009 USD), quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICER).

Results

Treatment of chronic HCV without fibrosis screening is preferred for both men and women. For genotype 1 patients treated with pegylated interferon and ribavirin, the ICERs are $5,400/QALY (men) and $6,300/QALY (women) compared to FibroTest only; the ICERs increase to $27,200/QALY (men) and $30,000/QALY (women) with the addition of telaprevir. For genotypes 2 and 3, treatment is more effective and less costly than all alternatives. In clinical settings where testing is required prior to treatment, FibroTest only is more effective and less costly than liver biopsy. These results are robust to multi-way and probabilistic sensitivity analyses.

Conclusions

Early treatment of chronic HCV is superior to the other fibrosis screening strategies. In clinical settings where testing is required, FibroTest screening is a cost-effective alternative to liver biopsy.     

The natural course of chronic hepatitis C

Abstract: In 1988, investigators from the Chiron Company (USA) detected the non-A, non-B agent and named it hepatitis C virus (HCV). An anti-HCV antibody assay (ELISA) and subsequently confirmation tests (immunoblot and polymerase chain reaction) were developed. HCV exposure results in a chronic infection in a majority of cases. This chronic infection is associated with slowly progressive chronic liver disease. Chronic HCV infection is, like HBV, also associated with the development of hepatocellular carcinoma. Most HCV carriers are infected by parenteral routes. Intravenous drug users have the highest risk of becoming infected. Intrafamiliar spread is seen in certain parts of the world but sexual and perinatal transmission does not play an important role in spreading the infection. Antiviral therapy (alpha-interferon) in patients with chronic hepatitis C will normalize liver function tests in about 25% of the cases.     

An IL28B genotype-based clinical prediction model for treatment of chronic hepatitis C

Background

Genetic variation in IL28B and other factors are associated with sustained virological response (SVR) after pegylated-interferon/ribavirin treatment for chronic hepatitis C (CHC). Using data from the HALT-C Trial, we developed a model to predict a patient''s probability of SVR based on IL28B genotype and clinical variables.

Methods

HALT-C enrolled patients with advanced CHC who had failed previous interferon-based treatment. Subjects were re-treated with pegylated-interferon/ribavirin during trial lead-in. We used step-wise logistic regression to calculate adjusted odds ratios (aOR) and create the predictive model. Leave-one-out cross-validation was used to predict a priori probabilities of SVR and determine area under the receiver operator characteristics curve (AUC).

Results

Among 646 HCV genotype 1-infected European American patients, 14.2% achieved SVR. IL28B rs12979860-CC genotype was the strongest predictor of SVR (aOR, 7.56; p<.0001); the model also included HCV RNA (log10 IU/ml), AST∶ALT ratio, Ishak fibrosis score and prior ribavirin treatment. For this model AUC was 78.5%, compared to 73.0% for a model restricted to the four clinical predictors and 60.0% for a model restricted to IL28B genotype (p<0.001). Subjects with a predicted probability of SVR <10% had an observed SVR rate of 3.8%; subjects with a predicted probability >10% (43.3% of subjects) had an SVR rate of 27.9% and accounted for 84.8% of subjects actually achieving SVR. To verify that consideration of both IL28B genotype and clinical variables is required for treatment decisions, we calculated AUC values from published data for the IDEAL Study.

Conclusion

A clinical prediction model based on IL28B genotype and clinical variables can yield useful individualized predictions of the probability of treatment success that could increase SVR rates and decrease the frequency of futile treatment among patients with CHC.     

Serum alpha-fetoprotein predicts treatment outcome in chronic hepatitis C patients regardless of HCV genotype

We examined the association between serum alpha-fetoprotein (AFP) level and sustained virological response (SVR) in 93 chronic hepatitis C patients. The SVR rate was much higher among patients with serum AFP levels below rather than above the median value (5.7 ng/ml) (58.7% and 19.2%, respectively; P<0.0001). Serum AFP should be added to the list of factors predictive of treatment response in chronic hepatitis C.     

Identification of treatment efficacy-related host factors in chronic hepatitis C by ProteinChip serum analysis

Recent development of proteomic array technology, including protein profiling coupling ProteinChip array with surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF/MS), provides a potentially powerful tool for discovery of new biomarkers by comparison of its profiles according to patient phenotypes. We used this approach to identify the host factors associated with treatment response in patients with chronic hepatitis C (CHC) receiving a 48-wk course of pegylated interferon (PEG-IFN) alpha 2b plus ribavirin (RBV). Protein profiles of pretreatment serum samples from 32 patients with genotype 1b and high viral load were conducted by SELDI-TOF/MS by using the three different ProteinChip arrays (CM10, Q10, IMAC30). Proteins showed significantly different peak intensities between sustained virological responders (SVRs), and non-SVRs were identified by chromatography, SDS-PAGE, TOF/MS and tandem mass spectrometry (MS/MS) assay. Eleven peak intensities were significantly different between SVRs and non-SVRs. The three SVR-increased peaks could be identified as two apolipoprotein (Apo) fragments and albumin and, among the eight non-SVR-increased proteins, four peaks identified as two iron-related and two fibrogenesis-related protein fragments, respectively. Multivariate analysis showed that the serum ferritin and three peak intensity values (Apo A1, hemopexin and transferrin) were independent variables associated with SVRs, and the area under the receiver operating characteristic (ROC) curves for SVR prediction by using the Apo A1/hemopexin and hemopexin/transferrin were 0.964 and 0.936. In conclusion, pretreatment serum protein profiling by SELDI-TOF/MS is variable for identification of response-related host factors, which are useful for treatment efficacy prediction in CHC receiving PEG-IFN plus RBV. Our data also may help us understand the mechanism for treatment resistance and development of more effective antiviral therapy targeted toward the modulation of lipogenesis or iron homeostasis in CHC patients.