Optimizing treatment regimens in hepatitis C

APASL consensus statements and management algorithms for hepatitis C virus infection

The Asian Pacific Association for the Study of the Liver (APASL) convened an international working party on the "APASL Consensus Statements and Management Algorithms for Hepatitis C Virus Infection" in December, 2010, in order to revise "Asian Pacific Association for the Study of the Liver consensus statements on the diagnosis, management and treatment of hepatitis C virus infection (J Gastroenterol Hepatol 22:615-633, 2007)". The working party consisted of expert hepatologists from the Asian-Pacific region gathered at Makuhari, Chiba, Japan on 19 December 2010. New data were presented, discussed and debated to draft a revision. Participants of the consensus meeting assessed the quality of cited studies. Finalized recommendations are presented in this review.

IL28B inhibits hepatitis C virus replication through the JAK-STAT pathway

BACKGROUND & AIMS

The combination of pegylated interferon (IFN) α and ribavirin (RBV) is the standard therapy for patients with chronic HCV infection. However, it produces a sustained virologic response (SVR) in only half of the treated individuals and is associated with significant side effects. Recently, several single-nucleotide polymorphisms (SNPs) near the IL28B locus, also known as IFNλ3, were identified to be strong predictors of SVR in patients receiving PEG-IFN and RBV. We sought to determine whether IL28B was capable of inhibiting HCV replication and to determine the pathway by which IL28B exhibits anti-HCV activity.

METHODS

Using the full-length HCV replicon OR6 and the infectious HCV clones JFH1 and Jc1, we assessed the anti-HCV effect of IL28B on HCV and characterized the key steps of the JAK-STAT pathway by real time PCR, luciferase assay, and Western blot. Finally, we evaluated the anti-HCV effect of IL28B in the presence of JAK-STAT pathway inhibitors such as blocking antibodies, a pharmacological inhibitor, and siRNAs.

RESULTS

We found that IL28B inhibits HCV replication in a dose- and time-dependent manner. Like IFNα, IL28B induces the phosphorylation of STAT1 and STAT2, ISRE-driven transcription, and expression of known ISGs. The anti-HCV effects of IL28A, IL28B, and IL29 were abrogated by an IL10R2 blocking antibody, a pharmacological inhibitor of JAK1/TYK2, and by siRNA against IL28R1, STAT1, STAT2, and IRF9.

CONCLUSIONS

Our data demonstrate that IL28A, IL28B, and IL29 signal through the JAK-STAT pathway to inhibit HCV. These data suggest possible applications of new approaches in HCV treatment.

Chronic hepatitis C

The goal of antiviral therapy for patients with chronic hepatitis C virus (HCV) infection is to attain a sustained virologic response (SVR), which is defined as undetectable serum HCV-RNA levels at 6 months after the cessation of treatment. Major improvements in antiviral therapy for chronic hepatitis C have occurred in the past decade. The addition of ribavirin to interferon-alfa therapy and the introduction of pegylated interferon (PEG-IFN) have substantially improved SVR rates in patients with chronic hepatitis C. The optimization of HCV therapy with PEG-IFN and ribavirin continues to evolve. Studies are ongoing that use viral kinetics to tailor therapy to an individual's antiviral response and determine the ideal length of treatment to maximize the chance of SVR. Improved SVR can be achieved with new specific inhibitors that target the HCV NS3/4A protease and the NS5B polymerase. Several long-term follow-up studies have shown that SVR, when achieved, is associated with a very low risk of virologic relapse. Furthermore, antiviral therapy can reduce the morbidity and mortality rates associated with chronic hepatitis C by reducing fibrosis progression, the incidence of cirrhosis, and hepatocellular carcinoma.

Evaluation of medication adherence and quality of life in patients with hepatitis C virus receiving combination therapy

The purpose of this study was to identify medication adherence for patients infected with hepatitis C virus (HCV) referred to an interdisciplinary HCV education and monitoring service, evaluate changes in quality of life (QOL) and medication adherence during the first 3 months of HCV therapy, and determine relationships between adherence and QOL. Patients completed an initial survey before initiating the therapy evaluating medication adherence and QOL. They then received a structured training on HCV medications and monthly monitoring phone call from a pharmacist throughout the therapy. After 3 months of treatment, a follow-up survey was conducted to evaluate adherence, satisfaction, and QOL. Medication adherence was also assessed via patient self-report during follow-up phone calls. Patients expressed satisfaction with the care provided by the pharmacist and nurse practitioner individually and working collaboratively during their HCV therapy. Patients reported taking 99.8% of total interferon and ribavirin doses during the first 3 months of the therapy. Patients who indicated that they sometimes stopped taking medication when they felt worse had higher median aggregate physical functioning scores (p = .04) and those with no comorbidities found dosage times more inconvenient than those with at least one comorbidity (p = .046). Patients in a pharmacist-run HCV education service have high self-reported adherence rates and are satisfied with the interdisciplinary model of care. Quality of life may be associated with adherence; higher functioning, healthier patients may be more likely to stop taking HCV medications owing to side effects or inconvenience.

Early gene expression profiles of patients with chronic hepatitis C treated with pegylated interferon-alfa and ribavirin

Responsiveness to hepatitis C virus (HCV) therapy depends on viral and host factors. Our aim was to assess sustained virologic response (SVR)-associated early gene expression in patients with HCV receiving pegylated interferon-alpha2a (PEG-IFN-alpha2a) or PEG-IFN-alpha2b and ribavirin with the duration based on genotypes. Blood samples were collected into PAXgene tubes prior to treatment as well as 1, 7, 28, and 56 days after treatment. From the peripheral blood cells, total RNA was extracted, quantified, and used for one-step reverse transcription polymerase chain reaction to profile 154 messenger RNAs. Expression levels of messenger RNAs were normalized with six "housekeeping" genes and a reference RNA. Multiple regression and stepwise selection were performed to assess differences in gene expression at different time points, and predictive performance was evaluated for each model. A total of 68 patients were enrolled in the study and treated with combination therapy. The results of gene expression showed that SVR could be predicted by the gene expression of signal transducer and activator of transcription-6 (STAT-6) and suppressor of cytokine signaling-1 in the pretreatment samples. After 24 hours, SVR was predicted by the expression of interferon-dependent genes, and this dependence continued to be prominent throughout the treatment.

CONCLUSION

Early gene expression during anti-HCV therapy may elucidate important molecular pathways that may be influencing the probability of achieving virologic response.

Improved outcomes in patients with hepatitis C with difficult-to-treat characteristics: randomized study of higher doses of peginterferon alpha-2a and ribavirin

Treatment response remains suboptimal for many patients with chronic hepatitis C, particularly those with genotype 1 and high levels of viremia. The efficacy of high-dose regimens of peginterferon alfa-2a and ribavirin was compared with conventional dose regimens in patients with features predicting poor treatment responses. Eligible treatment-naïve adults with genotype 1 infection, hepatitis C virus (HCV) RNA >800,000 IU/mL and body weight >85 kg were randomized to double-blind treatment with peginterferon alfa-2a at 180 or 270 microg/week plus ribavirin at 1200 or 1600 mg/day for 48 weeks (four regimens were evaluated). The primary endpoint was viral kinetics during the first 24 weeks of therapy. Among patients receiving peginterferon alfa-2a (270 microg/week) the magnitude of HCV RNA reduction was significantly greater than for patients randomized to the conventional dose of peginterferon alfa-2a (180 microg/week) for the pairwise comparison for ribavirin at 1600 mg/day (P = 0.036) and numerically greater for the pairwise comparison for ribavirin at 1200 mg/day (P = 0.060). Patients randomized to the highest doses of peginterferon alfa-2a (270 microg/week) and ribavirin (1600 mg/day) experienced the numerically highest rates of sustained virologic response (HCV RNA < 50 IU/mL) and the lowest relapse rate (47% and 19%, respectively). The arm with the higher doses of both drugs was less well-tolerated than the other regimens.

CONCLUSION

Higher fixed doses of peginterferon alfa-2a (270 microg/week) and ribavirin (1600 mg/day) may increase sustained virologic response rates compared with lower doses of both drugs in patients with a cluster of difficult-to-treat characteristics.

Hepatitis C: current options for nonresponders to peginterferon and ribavirin

Hepatitis C virus infection remains a significant health problem worldwide. The development of interferon-based therapies has led to increased success in eradicating this viral infection; however, no recent additions to the current treatment care regimen (peginterferon and ribavirin) have been made. Nonresponders to peginterferon/ribavirin make up a diverse patient population that can be difficult to manage. Through a better understanding of treatment response and viral kinetics, clinicians are employing altered dosing schedules to minimize the burden of viral illness. Consequently, clinicians can now manage nonresponders by providing supportive care and reserving retreatment for those most likely to respond to additional antiviral therapy, particularly when correctable factors from a previous treatment course with the potential for positive intervention have been identified. The decision for further medical management is based on clinical and laboratory parameters that have been shown to predict which patients will benefit most from another attempt at therapy.

Role and support for hepatologists at liver transplant programs in the United States

Liver transplantation has evolved into a successful option for patients with end-stage liver disease. Transplant hepatologists are involved in the management of patients with end-stage liver disease both before and after liver transplantation. The goals of this study were to evaluate the roles that transplant hepatologists play at liver transplantation programs in the United States and the demand for and institutional support provided for these physicians. A web-based questionnaire was sent via e-mail to the medical directors of all 108 United Network for Organ Sharing-recognized liver transplant programs during the fall of 2006. Follow-up e-mails were sent and phone calls were made to those not completing the survey within 4 weeks. The survey was completed by 72 (67%) medical directors. The average number of liver transplants performed per center was 62, and a broad range of program sizes were represented. The number of transplant hepatologists increased in proportion to the number of transplants performed on an annual basis but lagged behind the number of surgeons and transplant coordinators. On average, 33 liver transplants were performed per year per transplant hepatologist. Transplant hepatologists were involved in all aspects of pretransplant and posttransplant care at all but 10% of these institutions; they provided virtually all pretransplant care at all of these programs and all long-term posttransplant care at 45% of these programs. Overall, 94% of liver transplant programs provided direct salary support and/or ancillary personnel for their transplant hepatologists. Despite this, over half of transplant hepatologists and 75% of those that received no direct salary support performed endoscopic procedures on a regular basis. Eighty-one percent of programs were recruiting additional transplant hepatologists. In conclusion, although the vast majority of transplant hepatologists receive institutional support, this support appears to be inadequate. The current shortage of transplant hepatologists is likely to increase if appropriate support mechanisms are not implemented.