Peginterferon alfa-2b and ribavirin: effective in patients with hepatitis C who failed interferon alfa/ribavirin therapy

Hungarian consensus guideline for the diagnosis and treatment of B, C, and D viral hepatitis

More than 1% of the Hungarian population is infected with hepatitis B, C, or D viruses. Since 2006 the diagnostics and therapy of these infections are carried out in treatment centers according to national guidelines – since 2010 according to financial protocols. The consensus-based guidelines for 2012 are published in this paper. The guidelines stress the importance of quick and detailed virologic evaluations, the applicability of transient elastography as an acceptable alternative of liver biopsy in this regard, as well as the relevance of appropriate consistent follow up schedule for viral response during therapy. The first choice of therapy in chronic hepatitis B infection is pegylated interferon for 48 weeks or continuous entecavir therapy. The later must be continued for at least 6 months after hepatitis B surface antigen (HBsAg) seroconversion. Tenofovir disoproxil fumarat is not yet reimbursed by the National Health Insurance Fund. Adefovir dipivoxil is recommended mainly in combination therapy. Lamivudine is no longer a first choice; patients currently taking lamivudine must switch if response is inadequate. Appropriate treatment of patients taking immunosuppressive medications is highly recommended. Pegylated interferon based therapy is recommended for the treatment of concomitant hepatitis D infection. Treatment naive chronic hepatitis C patients should initially receive pegylated interferon and ribavirin dual combination therapy. In genotype 1 infection if response is insufficient at 4 or 12 weeks one of the two new direct acting antivirals (boceprevir or telaprevir) should be added. The length of treatment is usually 48 weeks; in cases of extended early viral response shorter courses are recommended. Previous treatment failure patients with genotype 1 infection should receive a protease inhibitor backed triple combination therapy, mostly for 48 weeks. However, relapsers without cirrhosis and with extended rapid viral response, shorter telaprevir based combination therapy is sufficient. Drug-drug interactions as well as emergence of viral resistance are of particular importance. For genotype 2 or 3 HCV infections 24 weeks, for genotype 4 infections 24, 48 or 72 weeks of pegylated interferon plus ribavirin therapy is recommended in general. The guidelines published here become protocols when published as official publications of the Hungarian Health Authority. Orv. Hetil., 2012, 153, 375–394.

Dual therapy with the nonstructural protein 5A inhibitor, daclatasvir, and the nonstructural protein 3 protease inhibitor, asunaprevir, in hepatitis C virus genotype 1b-infected null responders

Patients with chronic hepatitis C virus (HCV) infection and previous null response to pegylated interferon (Peg-IFN) and ribavirin (RBV) have limited therapeutic options. HCV genotype 1 is the most common worldwide and the most difficult to treat; genotype 1b is the most common subtype of genotype 1 outside North America. The enhanced antiviral activity achieved by combining two direct-acting antiviral (DAA) agents may improve clinical outcomes. This open-label, phase IIa study included 10 patients with chronic HCV genotype 1b infection and previous null response (<2 log(10) reduction in HCV RNA after 12 weeks) to Peg-IFN and RBV. Patients received dual DAA treatment for 24 weeks with the nonstructural protein 5A replication complex inhibitor, daclatasvir (60 mg once-daily), and the nonstructural protein 3 protease inhibitor, asunaprevir (initially 600 mg twice-daily, then subsequently reduced to 200 mg twice-daily). The primary efficacy endpoint was the proportion of patients with sustained virologic response (SVR) at 12 weeks post-treatment (SVR(12) ). Nine patients completed 24 weeks of treatment; 1 patient discontinued treatment after 2 weeks. In the 9 patients who completed the full course of treatment, HCV RNA was undetectable at week 8 and remained undetectable through the end of treatment; all 9 patients achieved SVR(12) and SVR(24) . HCV RNA also remained undetectable post-treatment in the patient who discontinued after 2 weeks. There was no viral breakthrough. Diarrhea and headache, generally mild, were the most common adverse events; transaminase elevations were reported in 3 patients, but did not result in discontinuation.

CONCLUSIONS

Dual therapy with daclatasvir and asunaprevir, without Peg-IFN and RBV, can achieve high SVR rates in difficult-to-treat patients with HCV genotype 1b infection and previous null response to Peg-IFN and RBV.

UK consensus guidelines for the use of the protease inhibitors boceprevir and telaprevir in genotype 1 chronic hepatitis C infected patients

BACKGROUND

The nonstructural 3 serine protease inhibitors (PIs), boceprevir and telaprevir, represent the first in a new generation of directly acting antivirals against genotype 1 hepatitis C (HCV) infection. When used in combination with pegylated interferon and ribavirin, these drugs greatly improve sustained virological response rates in both treatment-naïve patients and patients who have had previous virological failure on treatment. However, the addition of these new agents will increase the complexity of therapeutic regimens, the rates of side-effects and costs.

AIMS

To review concisely the current evidence and to suggest current best practice, for the use of telaprevir and boceprevir in the management of chronic genotype 1 HCV infection.

METHODS

These guidelines for the use of boceprevir and telaprevir have been formulated following extensive review of the current literature, are based on the consensus opinion of a panel of national experts, and have been openly discussed and debated at a national meeting of HCV care providers.

RESULTS

We have made recommendations on a number of the key practical issues facing HCV care providers: (i) Which patients to treat?; (ii) Standards for the provision of care; (iii) Pre-treatment considerations; (iv) Which treatment regimens to use?; (v) Stopping rules; and (vi) Management of adverse effects. Finally, we have produced suggested algorithms for the assessment and treatment of these patients.

CONCLUSIONS

These UK Consensus guidelines indicate the current best practice for the use of boceprevir and telaprevir in the management of genotype 1 chronic HCV infection.

Recent trends in the treatment of chronic hepatitis C

Pegylated interferon and ribavirin combination therapy is accepted as the standard antiviral treatment for chronic hepatitis C regardless of HCV genotype. This combination therapy achieves higher response rates than previous therapy, but, nevertheless, a large proportion of patients suffer from treatment failure or adverse events. Recent clinical studies of viral kinetics during antiviral treatment have led to the introduction of response-guided therapy, the concept of 'customized therapy depending on viral response', which focuses on modulation of the treatment period depending on the viral response to create a sustained viral response without unnecessary medication and costs. New upcoming direct-acting antivirals (DAAs) maximize response rate, and triple therapy including DAAs along with pegylated interferon and ribavirin combination therapy could soon be the standard therapy. In this article, we reviewed the factors affecting treatment, response guided treatment, retreatment after failure of standard treatment, management of adverse events during treatment, and new treatment options.

Continuous interferon-α2b infusion in combination with ribavirin for chronic hepatitis C in treatment-experienced patients

BACKGROUND

Sustained virological response (SVR) rates in previous non-responders to pegylated interferon (PEG-IFN)-α and ribavirin for chronic HCV remain low (~10%). We hypothesize that continuous subcutaneous delivery of fully potent interferon (IFN)-α2b via an external pump will lead to stable blood concentrations and thereby prevent subtherapeutic trough levels associated with viral breakthrough. The aims of the study were to assess safety, tolerability and virological response in patients who were previous PEG-IFN-α/ribavirin non-responders.

METHODS

We randomized 30 HCV genotype 1 (n=24) and genotype 4 (n=6) patients to receive 6, 9 or 12 million units (MU) IFN-α2b daily by continuous subcutaneous administration using an insulin pump (MiniMed(®) 508; Medtronic Inc., Minneapolis, MN, USA) in combination with ribavirin (1,000-1,600 mg) for 48 weeks.

RESULTS

The magnitude of viral decline in the 12 MU group after 4 weeks of treatment was 2.67 log HCV RNA compared with 1.21 and 1.27 log HCV RNA in the 9 and 6 MU groups, respectively (P=0.001). In the intention-to-treat analysis, the SVR rate was 20% (6/30). The per-protocol SVR rate was 25% (6/24), of which four out of six patients in the high-dose arm achieved SVR. Adverse events appeared dose-dependent, were mostly mild-to-moderate and were typical of IFN therapy. Five patients developed irritation and/or abscesses at the injection site. Six serious adverse events were reported in five patients.

CONCLUSIONS

Continuous delivery of IFN-α2b can induce a strong dose-dependent viral suppression. This could be an effective approach in conjunction with, or as lead-in therapy prior to, treatment with a direct antiviral agent.

2011 European Association of the Study of the Liver hepatitis C virus clinical practice guidelines

Hepatitis C virus (HCV) is the leading cause of liver transplantation in Europe and is associated with an increased risk of hepatocellular carcinoma (HCC). Because of the chronic nature of the disease, estimates suggest that the burden on healthcare will increase dramatically for this entity. Clinical care of patients with HCV-related liver disease has advanced considerably in the last two decades, thanks to increasing knowledge about the mechanisms of the disease, development of diagnostic procedures, and advances in therapeutic and preventive approaches. HCV RNA testing, HCV genotyping and staging of liver disease are essential for the diagnosis and the management of HCV therapy. Furthermore, the important role of host polymorphisms of the IL28B gene on virological response to treatment with pegylated interferon (PEG-IFN) alpha and ribavirin (RBV) has recently been clearly demonstrated. In relation to treatment, although numerous drugs for HCV are in various stages of preclinical and clinical development, the current standard of care (SoC) is the combination of PEG-IFN-α and RBV for chronic hepatitis C. With SoC, a sustained viral response (SVR) is achieved in approximately 45% of patients infected with HCV genotype 1 and in approximately 80% of patients infected with HCV genotypes 2 and 3. The EASL HCV guidelines recommend treating all naïve patients with compensated disease from HCV without contraindications to treatment and strongly suggest initiating SoC promptly in patients with advanced fibrosis. Further recommendations on monitoring treatment efficacy, treatment duration, dose reduction indications and the role of co-factors are provided.

Dynamics of regulatory T cells and plasmacytoid dendritic cells as immune markers for virological response in pegylated interferon-α and ribavirin therapy for chronic hepatitis C patients

BACKGROUND

For the treatment of chronic hepatitis C, a combination of pegylated interferon-α (PEG-IFNα) and ribavirin has been widely used as a standard of care. Enhancement of immune response against hepatitis C virus (HCV) is known to be involved in the efficacy of the combination therapy. Our aim was to elucidate whether or not the frequency or function of blood cells is related to the outcome of the therapy.

METHODS

Sixty-seven chronic hepatitis C patients with high viral load of HCV genotype 1 infection who underwent 48 weeks of PEG-IFNα2b and ribavirin therapy were examined. During the treatment, frequencies of myeloid or plasmacytoid dendritic cells, Th1, Th2 cells, NK cells, and regulatory T cells were phenotypically determined.

RESULTS

Among the patients enrolled, 29 showed a sustained virological response (SVR), 18 a transient response (TR) and 17 no response (NR). The clinical and immunological markers were compared between the SVR and non-SVR patients, including TR and NR. Based on clinical, histological, immunological parameters, and cumulative dosage of PEG-IFNα2b and ribavirin, multivariate analyses revealed that higher platelet counts and higher regulatory T cell frequency at week 12 are indicative of SVR. Even in patients who attained complete early virological response at week 12, multivariate analyses disclosed that higher platelet counts and higher plasmacytoid dendritic cell frequency are indicative of SVR.

CONCLUSIONS

In PEG-IFNα and ribavirin combination therapy for chronic hepatitis C patients, the increments of regulatory T cells and plasmacytoid dendritic cell frequency are independently related to favorable virological response to the therapy.

Efficacy and safety of telaprevir, a new protease inhibitor, for difficult-to-treat patients with genotype 1 chronic hepatitis C

The aims of this phase III study were to assess the efficacy and safety of telaprevir in combination with peginterferon alfa-2b (PEG-IFN) and ribavirin (RBV) for difficult-to-treat patients who had not achieved sustained virological response (SVR) to prior regimens in Japan. The subjects were 109 relapsers (median age of 57.0 years) and 32 nonresponders (median age of 57.5 years) with hepatitis C virus genotype 1. Patients received telaprevir (750 mg every 8 h) for 12 weeks and PEG-IFN/RBV for 24 weeks. The SVR rates for relapsers and nonresponders were 88.1% (96/109) and 34.4% (11/32), respectively. Specified dose modifications of RBV that differed from that for the standard of care were introduced to alleviate anaemia. RBV dose reductions were used for 139 of the 141 patients. The SVR rates for relapsers did not depend on RBV dose reduction for 20-100% of the planned dose (SVR rates 87.5-100%, P < 0.05). Skin disorders were observed in 82.3% (116/141). Most of the skin disorders were controllable by anti-histamine and/or steroid ointments. The ratios of discontinuation of telaprevir only or of all the study drugs because of adverse events were 21.3% (30/141) and 16.3% (23/141), respectively. A frequent adverse event leading to discontinuation was anaemia. Telaprevir in combination with PEG-IFN/RBV led to a high SVR rate for relapsers and may offer a potential new therapy for nonresponders even with a shorter treatment period.

Thymosin alpha-1 with peginterferon alfa-2a/ribavirin for chronic hepatitis C not responsive to IFN/ribavirin: an adjuvant role?

This study was conducted to determine whether the adding thymosin alpha-1 to standard of care for re-treatment of nonresponding hepatitis C infections can improve sustained viral response (SVR) rates. Patients (n = 552) with hepatitis C infections not responding to the combination of Peginterferon alfa-2a or 2b with ribavirin (RBV)were randomized to receive peginterferon alfa-2a 180 mg/week with RBV 800-1200 mg/daily plus either thymosin alpha-1 1.6 mg SC twice weekly (n = 275) or placebo (n = 277) for 48 weeks. Eighty-eight per cent of patients had HCV genotype 1, 6.6% type 4, 2.2% type 2 and 3.6% type 3. SVR rates in the intention to treat population were similar between thymosin alpha-1 and placebo (12.7%vs 10.5%; P = 0.407). Among patients who completed all 48 weeks of therapy, the SVR rate was significantly higher in the thymosin alpha-1 group at 41.0% (34/83) compared with 26.3% (26/99) in the placebo group (P = 0.048). No significant difference was observed between treatment groups in the incidence of adverse events. The addition of thymosin alpha-1 to the standard of care did not increase the on-treatment HCV viral response. Thymosin alpha-1 seems to play no role in the primary therapy of the disease. This study raises the hypothesis that thymosin alpha-1 may have a secondary therapeutic role as an adjuvant in the prevention of relapses in patients achieving a virologic response during therapy.

Discovery and development of telaprevir: an NS3-4A protease inhibitor for treating genotype 1 chronic hepatitis C virus

Infection with hepatitis C virus (HCV) is a major medical problem with over 170 million people infected worldwide. Substantial morbidity and mortality are associated with hepatic manifestations (cirrhosis and hepatocellular carcinoma), which develop with increasing frequency in people infected with HCV for more than 20 years. Less well known is the burden of HCV disease associated with extrahepatic manifestations (diabetes, B-cell proliferative disorders, depression, cognitive disorders, arthritis and Sjögren's syndrome). For patients infected with genotype 1 HCV, treatment with polyethylene glycol decorated interferon (peginterferon) α and ribavirin (PR) is associated with a low (40-50%) success rate, substantial treatment-limiting side effects and a long (48-week) duration of treatment. In the past 15 years, major scientific advances have enabled the development of new classes of HCV therapy, the direct-acting antiviral agents, also known as specifically targeted antiviral therapy for hepatitis C (STAT-C). In combination with PR, the HCV NS3-4A protease inhibitor telaprevir has recently been approved for treatment of genotype 1 chronic HCV in the United States, Canada, European Union and Japan. Compared with PR, telaprevir combination therapy offers significantly improved viral cure rates and the possibility of shortened treatment duration for diverse patient populations. Developers of innovative drugs have to blaze a new path with few validated sign posts to guide the way. Indeed, telaprevir's development was once put on hold because of its performance in a standard IC(50) assay. Data from new hypotheses and novel experiments were required to justify further investment and reduce risk that the drug might fail in the clinic. In addition, the poor drug-like properties of telaprevir were a formidable hurdle, which the manufacturing and formulation teams had to overcome to make the drug. Finally, novel clinical trial designs were developed to improve efficacy and shorten treatment in parallel instead of sequentially. Lessons learned from the development of telaprevir suggest that makers of innovative medicines cannot rely solely on traditional drug discovery metrics, but must develop innovative, scientifically guided pathways for success.

Usefulness of viral kinetics for early prediction of a sustained virological response in HCV-1 non-responders re-treated with pegylated interferon and ribavirin

BACKGROUND & AIMS

Undetectable HCV RNA at 12 weeks is the stopping rule recommended in HCV patients in whom previous treatment has failed. Whether earlier virological criteria may be useful for deciding treatment discontinuation remains subject of debate. The aim of this study was to identify, in HCV-1 non-responders and relapsers to IFN or Peg-IFN and ribavirin, the earliest and most accurate predictor of failure to respond to a new treatment combining Peg-IFN and ribavirin.

METHODS

Prediction of SVR was assessed using the area under the ROC (AUROC) curve of reduction in viral load at different time points.

RESULTS

This study included 151 patients (32% with extensive fibrosis or cirrhosis). A SVR was reached in 34% (21% in non-responders and 59% in relapsers). In non-responders, 1 month was the most accurate time point for predicting SVR (AUROC: 0.787 ± 0.075, p = 0.0001). Thirty-seven percent of non-responders did not have a 1-log drop in viral load at 1 month. All these patients had detectable HCV RNA at 3 months (p < 0.0001) and only 4% attained a SVR (p = 0.004). The same high negative predictive value for SVR was found in sensitivity analysis restricted to non-responders to Peg-IFN and ribavirin. In contrast, in relapsers, undetectable HCV RNA at 3 months was the earliest criterion with high negative predictive value (92%, p < 0.0001).

CONCLUSIONS

All HCV-1 non-responders who did not have a 1-log drop in viral load at 1 month remained HCV-RNA-detectable at 3 months, and only 4% attained a SVR. This new criterion can be used early on as a first stopping rule.

Retreatment with telaprevir combination therapy in hepatitis C patients with well-characterized prior treatment response

Retreatment with peginterferon alpha and ribavirin (PR) offers a limited chance of sustained virologic response (SVR) in patients who did not achieve SVR with prior PR treatment. This study evaluated the safety and efficacy of telaprevir-based treatment in combination with PR in well-characterized patients who did not achieve SVR in the control arms of three Phase II clinical trials. Patients eligible to enroll in this open-label nonrandomized study either met on-treatment criteria for nonresponse or relapsed after 48 weeks of treatment in the control arm of the three Phase II PROVE studies. The initial protocol was a 24-week regimen: 12 weeks of telaprevir and PR followed by an additional 12 weeks of PR. During the study the protocol was amended to extend PR to 48 weeks for patients with previous null response. All other patients with undetectable hepatitis C virus (HCV) RNA at weeks 4 and 12 received 24 weeks of therapy. Those with detectable HCV RNA at weeks 4 or 12 received a total of 48 weeks of therapy. The overall SVR rate was 59% (69/117). SVR rates with T12PR were 37% (19/51) in prior null responders, 55% (16/29) in prior partial responders, 75% (6/8) in prior breakthroughs, and 97% (28/29) in prior relapsers. The overall relapse rate was 16% (13/83). Adverse events were similar to those in previous trials with telaprevir, with 9% of patients discontinuing due to an adverse event (most commonly rash and anemia).

CONCLUSION

This study demonstrated the benefit of retreatment with a telaprevir-based regimen for patients with well-characterized nonresponse (null and partial) or relapse to a prior course of PR treatment.

Role of integrins in fibrosing liver diseases

Integrins and other cell adhesion molecules regulate numerous physiological and pathological mechanisms by mediating the interaction between cells and their extracellular environment. Although the significance of integrins in the evolution and progression of certain cancers is well recognized, their involvement in nonmalignant processes, such as organ fibrosis or inflammation, is only beginning to emerge. However, accumulating evidence points to an instrumental role of integrin-mediated signaling in a variety of chronic and acute noncancerous diseases, particularly of the liver.

Retreatment of patients with chronic hepatitis C relapsers to a previous antiviral treatment

BACKGROUND

The efficacy of retreatment with pegylated interferon (PEG-IFN) plus ribavirin for patients relapsing after a previous treatment remains to be fully elucidated, although extended treatment seems to be the best option in such cases.

AIM

To evaluate the efficacy of two extended protocols in patients with genotypes 1 or 4, or those with genotypes 2 or 3.

METHODS

A total of 181 patients who had relapsed after a previous antiviral treatment with PEG-IFNα2a plus weight-based ribavirin were offered retreatment with the same dose of both PEG-IFN plus ribavirin, to be continued for 48 weeks in those with genotypes 2 or 3 (group 1), and for 72 weeks in those with genotypes 1 or 4 (group 2).

RESULTS

A total of 59 patients (32.5%) refused the retreatment, while 122 (78 men, 44 women) patients were enrolled in the study: 41 were allocated in group 1 and 81 in group 2. Cirrhosis at baseline (staging 5/6 according to Ishak's score was recorded in 11 patients, six in group 1 and five in group 2). Nine patients (7.3%) in group 2 discontinued the treatment (due to lack of response). The remaining patients completed the treatment and were followed-up for at least 12 months after the treatment. Sustained virological response (SVR) rate was 82.9% in group 1 and 50.6% in group 2.

CONCLUSION

Patients with chronic hepatitis C with 'easy genotypes' relapsers to a previous antiviral treatment have more than 80% probability of achieving a SVR with a 48-week retreatment. Patients with 'difficult genotypes' have more than 50% chance of a SVR after a 72-week extended treatment.

Efficacy of re-treatment with pegylated interferon plus ribavirin combination therapy for patients with chronic hepatitis C in Japan

BACKGROUND

It is still not known which patients with chronic hepatitis C who failed to respond to previous pegylated interferon (Peg-IFN) plus ribavirin therapy can benefit from re-treatment.

METHODS

Seventy-four patients (HCV genotype 1, n = 56, genotype 2, n = 18) were re-treated with Peg-IFN plus ribavirin.

RESULTS

On re-treatment, the sustained virologic response (SVR) rate was 41% for genotype 1 and 56% for genotype 2. With genotype 1, the factors associated with an SVR were previous treatment response and the serum hepatitis C virus (HCV) RNA level at the start of re-treatment. Patients with a ≥ 2-log decrease in HCV RNA at week 12 (partial early virologic response, p-EVR) in previous treatment had significantly higher SVR rates than those without these decreases (p < 0.001); no patient without a p-EVR in the previous treatment attained an SVR with re-treatment (0/16). All patients with <5 log(10) IU/ml of HCV RNA at the start of re-treatment attained an SVR (6/6), while only 33% (15/45) of those patients with ≥ 5 log(10) IU/ml of HCV RNA attained an SVR (p < 0.01). Among the patients with relapse in the previous treatment, those who attained an SVR on re-treatment required a longer duration of re-treatment than the duration of the previous treatment (re-treatment, 63.8 ± 13.0 weeks vs. previous treatment, 53.9 ± 13.5 weeks, p = 0.01).

CONCLUSIONS

Re-treatment of genotype 1 patients should be limited to patients with a p-EVR in the previous treatment and a low HCV RNA level at the start of re-treatment. In re-treatment with Peg-IFN plus ribavirin, longer treatment duration can contribute to increasing the anti-viral effect.

Management of the treatment-experienced patient infected with hepatitis C virus genotype 1: options and considerations

Individuals infected with hepatitis C virus (HCV) are at risk for cirrhosis and/or hepatocellular carcinoma. Treatment of HCV infection has undergone several revisions over the past 15 years and continues to evolve. The current major advance is with the protease inhibitors in addition to pegylated interferon and ribavirin. The emergence of resistance needs to be monitored carefully as newer and more potent drugs are added to the interferon and ribavirin backbone drugs. In addition, adverse events will be more frequent and some novel ones will require special attention.

The NS5A replication complex inhibitors: difference makers?

The development and approval of direct-acting antiviral agents looks set to transform the treatment of chronic hepatitis C infection. Among the agents in development are novel compounds that inhibit the function of the NS5A protein: a pleiotropic protein with a complex and essential role in viral replication. Preclinical studies have demonstrated the potency of these agents across a broad range of viral genotypes, and in early phase trials, they rapidly suppressed viral replication when administered as monotherapy or in combination with pegylated interferon-α and ribavirin. The discovery and development of NS5A replication complex inhibitors is summarized in this review.

New treatments for chronic hepatitis C virus infection

The treatment of hepatitis C virus infection (HCV) by a combination of pegylated interferon and ribavirin, according to early viral kinetics, leads to a sustained virological response (SVR) in more than 50% of patients with chronic infection. This SVR is a complete recovery of the infection but more than 50% of genotype 1-infected patients do not achieve SVR. A better understanding of the viral cycle, and the characterization of viral enzymes which are potential targets, resulted in the development of new molecules, direct acting antivirals (DAA) targeted against HCV, either specific of genotype 1 (protease inhibitors NS3/NS4A and polymerase inhibitors NS5B) or with a wider spectrum (NS5A or entry inhibitors), and non-specific antivirals (new interferons, cyclophilin inhibitors). We describe the results of phase II and III trials which clearly demonstrated a 20 to 30% increase in the SVR rate of genotype 1-infected patients, either naïve or treatment experienced. These new drugs should be approved by the end of 2011, after a temporary approval for compassionate use in cirrhotic patients with previous relapse or partial response to the combination therapy. In the future, the main limitations of triple therapy will be safety (cutaneous rash or anemia which may be controlled), cost, compliance, viral resistance, and drug interactions that must be avoided by educating patients and physicians.

High-dose pegylated interferon-α and ribavirin in nonresponder hepatitis C patients and relationship with IL-28B genotype (SYREN trial)

BACKGROUND & AIMS

In patients with chronic hepatitis C who failed to respond to standard therapy, high-dose pegylated interferon (IFN)-α and/or ribavirin could induce a stronger antiviral response and prevent treatment failure and HCV resistance when combined with direct-acting antivirals. The influence of genetic determinants in this context remains unknown.

METHODS

Eighty-three patients infected with HCV genotype 1 who were nonresponsive to standard therapy received pegylated IFN-α2a (360 μg once per week or 180 μg twice per week) with ribavirin (1.0-1.2 or 1.2-1.6 g/d) for up to 72 weeks. Virological responses were assessed at different time points, and the influence of the IL-28B genotype was studied.

RESULTS

At weeks 12 and 24, respectively, 47 (56.6%) and 50 (60.2%) patients achieved a ≥2-Log10 decrease of HCV RNA levels; 8 (9.6%) and 21 (25.3%) patients had undetectable HCV RNA after 12 and 24 weeks of treatment, respectively. Patients with a CT IL-28B genotype responded significantly better and earlier than those with a TT genotype. In multivariate analysis, the IL-28B genotype was an independent predictor of the virological responses at weeks 4, 12, and 24.

CONCLUSIONS

High-dose pegylated IFN-α with standard or high doses of ribavirin induces a potent antiviral response in a substantial number of patients who did not respond to standard therapy. The IL-28B genotype is an independent predictor of the antiviral response. High-dose pegylated IFN-α in combination with ribavirin and protease inhibitors appears as an attractive option for future study in this population.

Current therapies for chronic hepatitis C

Hepatitis C virus affects more than 180 million people worldwide and as many as 4 million people in the United States. Given that most patients are asymptomatic until late in the disease progression, diagnostic screening and evaluation should be performed in patients who display high-risk behaviors associated with acquisition of hepatitis C. Chronic hepatitis C is associated with cirrhosis, hepatic failure, and death; therefore, treatment is aimed at reducing these complications, as well as improving quality of life and minimizing adverse effects. The American Association for the Study of Liver Diseases Practice Guidelines on the Diagnosis, Management, and Treatment of Hepatitis C represent the gold standard for guidance on the management of hepatitis C. Standard treatment for hepatitis C is peginterferon alpha in combination with ribavirin. Currently, two pegylated interferon products are approved by the U.S. Food and Drug Administration for the treatment of hepatitis C. The duration of therapy with peginterferon and ribavirin is dictated by viral genotype and virologic response. Additional therapies are under investigation for treatment of chronic hepatitis C and show early promise of comparative efficacy and fewer adverse effects. Special considerations in certain populations, including patients coinfected with human immunodeficiency virus, those with end-stage renal disease, injection drug users, pregnant women, and pediatric patients, should guide treatment decisions.

Telaprevir for retreatment of HCV infection

BACKGROUND

Up to 60% of patients with hepatitis C virus (HCV) genotype 1 infection do not have a sustained virologic response to therapy with peginterferon alfa plus ribavirin.

METHODS

In this randomized, phase 3 trial, we evaluated the addition of telaprevir to peginterferon alfa-2a plus ribavirin in patients with HCV genotype 1 infection who had no response or a partial response to previous therapy or who had a relapse after an initial response. A total of 663 patients were assigned to one of three groups: the T12PR48 group, which received telaprevir for 12 weeks and peginterferon plus ribavirin for a total of 48 weeks; the lead-in T12PR48 group, which received 4 weeks of peginterferon plus ribavirin followed by 12 weeks of telaprevir and peginterferon plus ribavirin for a total of 48 weeks; and the control group (PR48), which received peginterferon plus ribavirin for 48 weeks. The primary end point was the rate of sustained virologic response, which was defined as undetectable HCV RNA 24 weeks after the last planned dose of a study drug.

RESULTS

Rates of sustained virologic response were significantly higher in the two telaprevir groups than in the control group among patients who had a previous relapse (83% in the T12PR48 group, 88% in the lead-in T12PR48 group, and 24% in the PR48 group), a partial response (59%, 54%, and 15%, respectively), and no response (29%, 33%, and 5%, respectively) (P<0.001 for all comparisons). Grade 3 adverse events (mainly anemia, neutropenia, and leukopenia) were more frequent in the telaprevir groups than in the control group (37% vs. 22%).

CONCLUSIONS

Telaprevir combined with peginterferon plus ribavirin significantly improved rates of sustained virologic response in patients with previously treated HCV infection, regardless of whether there was a lead-in phase. (Funded by Tibotec and Vertex Pharmaceuticals; REALIZE ClinicalTrials.gov number, NCT00703118.).

The sustained virologic response of nonresponder hepatitis C virus patients with retreatment

BACKGROUND

Pegylated interferon and ribavirin combination therapy remain the first-line treatment for chronic hepatitis C virus (HCV) infection. In contrast to the large number of studies in treatment-naive patients, the effectiveness of retreatment in patients who have previously failed pegylated interferon based therapy is not much reported.

OBJECTIVES

The aim of this retrospective study was to focus on the efficacy of pegylated interferon alpha and ribavirin in retreated chronic hepatitis C patients.

PATIENTS AND METHODS

All patients were treated with pegylated interferon alpha either 2a (180 μg) or 2b (1.5μg/kg) subcutaneously once weekly for a 48-week period, plus ribavirin 1000-1200 mg/day. The patient who had a negative HCV RNA at the end of 48 weeks were followed up for 24 weeks, and the patients who relapsed in the post-treatment follow-up period of 24 weeks were treated again with pegylated interferon alpha; but if the first treatment was administered with pegylated interferon alpha 2a, the second was administered with pegylated interferon alpha 2b and if pegylated interferon alpha 2b, then the second with pegylated interferon alpha 2a.

RESULTS

We evaluated the outcome of our patients with chronic HCV who achieved a viral response at the end of the therapy, but did not achieve sustained virologic response; 54% (38/70) of patients did achieve sustained virologic response, while 46% (32/70) of patients did not (eight patients did not achieve early virologic response, five patients were nonresponders at 24th week of the treatment, the remaining 19 patient had negative HCV at the end of the therapy but did not achieve sustained virologic response). We began from 19 patients to 8 patients, who had negative HCV RNA at the end of the treatment, but did not achieve sustained virologic response, interferon plus ribavirin therapy again. If the patient had interferon alpha 2a, we gave in the second tour alpha 2b; and if alpha 2b, then alpha 2a. The early virologic response of these nine patients were found to be 63% (5/8). These 5 patients who had rapid virologic response and early virologic response at the second therapy achieved sustained virologic response this time.

CONCLUSIONS

These findings suggest that the standard 48-week treatment is insufficient and that an extended course of treatment may be necessary. Relapse is a poorly understood clinical outcome in the treatment of chronic HCV patients. Retreatment can give a chance to some patients specially who have early virologic response and negative HCV RNA at the end of the first therapy.

Mechanisms of non-response to antiviral treatment in chronic hepatitis C

Treatment of chronic hepatitis C virus (HCV) infection has substantially evolved over the past decade after the Consensus Conference organized by the European Association for the Study of the Liver in 1999. Since then, the standard of care (SOC) for patients with chronic hepatitis C has been the combination of pegylated interferon (pegIFN) alpha-2a or -2b and ribavirin. In patients infected with HCV genotype 1, by far the most frequent HCV genotype worldwide, such treatment leads to a cure of infection in only 40% to 50% of cases. Several factors have been identified to play a role in the outcome of therapy, including the treatment schedule, disease characteristics, viral, and host factors. Human genetic factors have been identified by a recent landmark discovery. However, these factors only partly explain the ability of IFN and ribavirin therapy to cure HCV infection. Several studies have demonstrated that, in non-responders, interferon-stimulated genes were up-regulated prior to therapy through unclear mechanisms. These findings, together with clinical, biochemical and histological data, may help better identify responders before starting therapy. This becomes particularly important as the standard treatment is physically and economically demanding. The future treatment of patients infected with HCV genotype 1 will be based on the combination of pegIFN and ribavirin with a protease inhibitor, telaprevir or boceprevir. Promising results of this triple combination in phase III clinical trials have been recently reported at the Liver Meeting 2010. With this therapy, higher cure rates will be achieved, but specific issues will be raised, such as the emergence of resistance to the protease inhibitors. The goal of this review is to discuss mechanisms involved in the non-response to current and future standard treatments.

Ribavirin for chronic hepatitis C: and the mystery goes on

Twenty years ago, ribavirin was first used in the treatment for chronic hepatitis C. After few years, ribavirin, in combination with interferon-alpha, showed a dramatic synergistic efficacy against hepatitis C virus infection, leading to viral clearance in about 50% of patients. Recent discovery of potent inhibitors of hepatitis C virus proteases did not replace ribavirin as the mainstay of combination therapy for chronic hepatitis C. Despite this fundamental role of ribavirin, many aspects of the mechanism of action and of the optimal dose and duration of therapy remain to be discovered or settled. In the present review, the authors recall the milestones in the history of ribavirin and try to shed light on the more relevant features of ribavirin action and utilization, and on the clinical problems encountered in managing and optimizing treatment for chronic hepatitis C. Finally, some potential off-label use of this drug in most difficult-to-treat subjects is pointed out. In conclusion, even if a sort of mystery surrounds ribavirin, its efficacy against hepatitis C virus infection fortunately remains lasting and stable.

Maintenance therapy with peginterferon alfa-2b does not prevent hepatocellular carcinoma in cirrhotic patients with chronic hepatitis C

BACKGROUND & AIMS

Several studies have reported that low doses of interferon can delay the development of hepatocellular carcinoma (HCC) and progression of chronic hepatitis C. We investigated the incidence of clinical events among participants of the Evaluation of PegIntron in Control of Hepatitis C Cirrhosis (EPIC)3 program.

METHODS

Data were analyzed from an open-label randomized study of patients with chronic hepatitis C who had failed to respond to interferon alfa plus ribavirin. All patients had compensated cirrhosis with no evidence of HCC. Patients received peginterferon alfa-2b (0.5 μg/kg/week; n=311) or no treatment (controls, n=315) for a maximum period of 5 years or until 98 patients had a clinical event (hepatic decompensation, HCC, death, or liver transplantation). The primary measure of efficacy was time until the first clinical event.

RESULTS

There was no significant difference in time to first clinical event among patients who received peginterferon alfa-2b compared with controls (hazard ratio [HR], 1.452; 95% confidence interval [CI]: 0.880-2.396). There was no decrease in the development of HCC with therapy. The time to disease progression (clinical events or new or enlarged varices) was significantly longer for patients who received peginterferon alfa-2b compared with controls (HR, 1.564; 95% CI: 1.130-2.166). In a prospectively defined subanalysis of patients with baseline portal hypertension, peginterferon alfa-2b significantly increased the time to first clinical event compared with controls (P=.016). There were no new safety observations.

CONCLUSIONS

Maintenance therapy with peginterferon alfa-2b is not warranted in all patients and does not prevent HCC. However, there is a potential clinical benefit of long-term suppressive therapy in patients with preexisting portal hypertension.

Does interferon therapy prevent hepatocellular carcinoma in patients with chronic viral hepatitis?

Chronic hepatitis C and B are well-recognized and potentially preventable risk factors for hepatocellular carcinoma (HCC) development. Clinical and epidemiological studies suggest that therapy with interferon-α may reduce the overall risk of HCC development in patients with chronic hepatitis C, who achieve sustained virological response, but even in those who fail to eradicate the infection. In chronic hepatitis B, interferon therapy reduces the risk of HCC development in HBeAg-positive and cirrhotic patients who achieve persistent suppression of viral replication, while in HBeAg-negative patients the beneficial effect of interferon-α is not definitively confirmed. The preventive role of interferon-α after potentially curative treatment for HCC in both chronic hepatitis B and C is uncertain due to methodological flaws of the existing studies and prospective randomized controlled trials with pegylated interferon-α are needed to clarify this issue.

A new standard of care for the treatment of chronic HCV infection

The introduction of direct acting antiviral agents (DAAs) will markedly change treatment options for individuals who have a chronic HCV infection. Within the next few months, licensing of two HCV protease inhibitors (boceprevir and telaprevir) for the treatment of patients with chronic hepatitis C as part of a triple therapy with PEG-IFN-α and ribavirin is anticipated in the USA, Europe and many other countries. Final results of pivotal phase III clinical trials in previously untreated and treatment-experienced patients with HCV genotype 1 infection were presented at the Annual Meeting of the American Association for the Study of the Liver 2010 held in Boston, MA, USA, and at the Annual Conference of the Asian Pacific Association for the Study of the Liver 2011, held in Bangkok, Thailand. This article summarizes the results of these phase III trials in consideration of accumulating data on important baseline and on-treatment predictive factors for treatment response, such as the host IL28B genotype and the rapid virologic response; the introduction of these new therapies into clinical practice is also covered. Furthermore, preliminary data on the combination of different classes of DAAs, such as HCV protease inhibitors and HCV polymerase inhibitors, without interferon α are discussed.

Neutralizing antibodies to interferon-α and circulating interferon in patients with chronic hepatitis C non-responding to pegylated interferon plus ribavirin re-treated by pegylated interferon-α-2a and ribavirin (ANRS HC16 GAMMATRI substudy)

A lack of antiviral response in patients with chronic hepatitis C treated with pegylated (PEG)-interferon (IFN)-α-2a + ribavirin (RIBA) may be explained by neutralizing antibodies to IFN-α-2a. The aim of this study was to assess neutralizing antibodies to IFN-α-2a and IFN levels in non-responder patients who were re-treated by PEG IFN-α-2a and RIBA for 12 weeks. Non-responders to a first-line treatment of PEG IFN-α-2a + RIBA were included for treatment with PEG IFN-α-2a (180 µg/week) + RIBA (1,000 mg/day if <75 kg, 1,200 mg otherwise) for 48 weeks. HCV RNA was measured at week 12. IFN levels and neutralizing antibodies to IFN-α-2a were measured retrospectively on stored sera at baseline and weeks 4 and 12, using a quantitative sandwich ELISA for neutralizing antibodies to IFN-α-2a. Twenty-three patients were non-responders and 19 patients were responders at week 12 of the initial phase of the second-line treatment. Non-responders and responders did not differ statistically: baseline age (median age 47 vs. 50 years), HCV RNA (median 6.8 vs. 6.4 log(10) copies/ml), gender (70% vs. 73% males), genotype (genotype 1: 91% vs. 80%). The median IFN-α-2a levels (pg/ml) at weeks 0, 4, and 12 (interquartile range) did not differ between the 19 responders to initial phase of second-line treatment and the 23 non-responders: <3.3 (<3.3-371.4), 1457.3 (106.8-3284.8), and 1,652 (90.8-5,000); 84.5 (3.3-277.4), 1407.4 (120.2-2443.4), and 1620.1 (120.2-2287.1), respectively. Among non-selected consecutive non-responder patients, re-treatment with PEG IFN-α-2a + RIBA is associated with virological response regardless of the presence of antibody-mediated resistance to conventional IFN treatment.

FibroTest is an independent predictor of virologic response in chronic hepatitis C patients retreated with pegylated interferon alfa-2b and ribavirin in the EPIC³ program

BACKGROUND & AIMS

EPIC-3 is a prospective, international study that has demonstrated the efficacy of PEG-IFN alfa-2b plus weight-based ribavirin in patients with chronic hepatitis C and significant fibrosis who previously failed any interferon-alfa/ribavirin therapy. The aim of the present study was to assess FibroTest (FT), a validated non-invasive marker of fibrosis in treatment-naive patients, as a possible alternative to biopsy as the baseline predictor of subsequent early virologic (EVR) and sustained virologic response (SVR) in previously treated patients.

METHODS

Of 2312 patients enrolled, 1459 had an available baseline FT, biopsy, and complete data. Uni- (UV) and multi-variable (MV) analyses were performed using FT and biopsy.

RESULTS

Baseline characteristics were similar as in the overall population; METAVIR stage: 28% F2, 29% F3, and 43% F4, previous relapsers 29%, previous PEG-IFN regimen 41%, high baseline viral load (BVL) 64%. 506 patients (35%) had undetectable HCV-RNA at TW12 (TW12neg), with 58% achieving SVR. The accuracy of FT was similar to that in naive patients: AUROC curve for the diagnosis of F4 vs F2=0.80 (p<0.00001). Five baseline factors were associated (p<0.001) with SVR in UV and MV analyses (odds ratio: UV/MV): fibrosis stage estimated using FT (4.5/5.9) or biopsy (1.5/1.6), genotype 2/3 (4.5/5.1), BVL (1.5/1.3), prior relapse (1.6/1.6), previous treatment with non-PEG-IFN (2.6/2.0). These same factors were associated (p ≤ 0.001) with EVR. Among patients TW12neg, two independent factors remained highly predictive of SVR by MV analysis (p ≤ 0.001): genotype 2/3 (odds ratio=2.9), fibrosis estimated with FT (4.3) or by biopsy (1.5).

CONCLUSIONS

FibroTest at baseline is a possible non-invasive alternative to biopsy for the prediction of EVR at 12 weeks and SVR, in patients with previous failures and advanced fibrosis, retreated with PEG-IFN alfa-2b and ribavirin.

Peginterferon and ribavirin treatment for hepatitis C virus infection

Pegylated interferon α (IFNα) in combination with ribavirin is currently recommended as a standard-of-care treatment for chronic hepatitis C virus (HCV) infection. This combination therapy has drastically improved the rate of sustained virological response, specifically in difficult-to-treat patients. Recently, individualized treatment, such as response-guided therapy, is being developed based on host-, HCV- and treatment-related factors. Furthermore, modified regimens with currently available medications, novel modified IFNα and ribavirin or combinations with specifically targeted antiviral therapy for HCV agents, are currently being investigated. The purpose of this review is to address some issues and epoch-making topics in the treatment of chronic HCV infection, and to discuss more optimal and highly individualized therapeutic strategies for HCV-infected patients.

Intravenous silibinin as 'rescue treatment' for on-treatment non-responders to pegylated interferon/ribavirin combination therapy

BACKGROUND

Intravenous silibinin (ivSIL) is a potent antiviral agent against HCV. In vitro silibinin (SIL) inhibits viral replication, possibly by inhibiting HCV RNA polymerase. In this proof-of-concept study, ivSIL was tested in on-treatment non-responders to full-dose of pegylated interferon-α2a/ribavirin (standard of care [SOC]).

METHODS

A total of 27 treatment-naive patients with <2 log drop in viral load after 12 weeks or still detectable HCV RNA after 24 weeks of SOC treatment (mean age 54.4 ±6.8 years, male/female 19/8, HCV genotype 1 n=19, 3a n=4 and 4 n=4, liver fibrosis F4 n=14, F3 n=5 and F2 n=3, and interleukin 28B polymorphism C/C n=1, T/C n=22 and T/T n=4) received additionally 20 mg/kg/day SIL (Legalon-SIL(®); Rottapharm-Madaus, Monza, Italy) intravenously for 14 or 21 days. Thereafter, pegylated interferon/ribavirin was continued. HCV RNA was quantified by TaqMan(®) (Roche Diagnostics, Pleasanton, CA, USA).

RESULTS

At the end of ivSIL treatment, 23/27 (85.1%) patients had undetectable HCV RNA. In one of the four remaining patients HCV RNA became undetectable 8 weeks after ivSIL on SOC. Five patients relapsed after ivSIL, three of them responded to repeated administration of ivSIL, but relapsed again. The best predictor of response was a low pre-ivSIL HCV RNA level. A total of 19 patients reached one treatment end point (end of SOC treatment HCV RNA undetectable n=11 and non-response n=8); 8 patients were still on SOC (all HCV-RNA-negative). All 11 patients with end-of-treatment response completed 24 weeks of follow-up; 7 patients remained HCV-RNA-negative and 4 relapsed. Except for a slight increase in bilirubin (mean ±SD 0.98 ±0.35 to 2.12 ±0.99 mg/dl), treatment was well-tolerated.

CONCLUSIONS

ivSIL is an effective 'rescue treatment' for on-treatment non-responders to full-dose of SOC.

Current antiviral combination therapy for chronic hepatitis C patients who failed to interferon alfa-based treatment

WHAT IS KNOWN AND OBJECTIVE

Interferon-alfa-based therapy is effective in the treatment of Hepatitis C. However, some patients fail to respond and others relapse, after initially responding. Our objective was to assess the efficacy, safety and predictive factors for sustained virological response (SVR) to peginterferon plus ribavirin in chronic hepatitis C patients who failed to interferon-alfa (IFNα)-based therapy.

METHODS

Seventy-five consecutive patients who failed to IFNα-based therapy were retreated with peginterferon plus ribavirin. Of these patients, 85% were infected by genotype 1. The primary endpoint was SVR.

RESULTS AND DISCUSSION

Of 75 non-responder (n = 54) or relapser patients (n = 21), 50 were previously treated with IFNα-monotherapy and 25 with IFNα plus ribavirin. Global SVR rate was 41.3%: for patients re-treated with IFNα the response was 48% whilst for those retreated with IFNα plus ribavirin, it was 28%. For previous non-responders the SVR rate was 37% and for relapsers it was 52.4%.

WHAT IS NEW AND CONCLUSION

Retreatment with peginterferon plus ribavirin is an effective option for some chronic hepatitis C non-responder or relapser patients. Higher SVR rate was achieved in relapsers and in those patients who received IFNα monotherapy previously.

S-adenosyl-methionine and betaine improve early virological response in chronic hepatitis C patients with previous nonresponse

BACKGROUND/AIMS

Treatment of chronic hepatitis C (CHC) with pegylated interferon α (pegIFNα) and ribavirin results in a sustained response in approximately half of patients. Viral interference with IFNα signal transduction through the Jak-STAT pathway might be an important factor underlying treatment failure. S-adenosyl-L-methionine (SAMe) and betaine potentiate IFNα signaling in cultured cells that express hepatitis C virus (HCV) proteins, and enhance the inhibitory effect of IFNα on HCV replicons. We have performed a clinical study with the aim to evaluate efficacy and safety of the addition of SAMe and betaine to treatment of CHC with pegIFNα/ribavirin.

METHODS

In this open-label pilot study, 29 patients with CHC who failed previous therapy with (peg)IFNα/ribavirin were treated with SAMe, betaine, pegIFNα2b and ribavirin. Treatment duration was 6 or 12 months, depending on genotype, and the protocol comprised a stopping rule at week 12 if early virological response (EVR) was not achieved. Virological and biochemical response and safety were assessed throughout the treatment.

RESULTS

29 patients were enrolled and treated according to the study protocol. 79% of the patients were infected with genotype 1, 72% had advanced fibrosis, 76% had previously received pegIFNα/ribavirin, and only 14% achieved EVR to the previous treatment. When treated with the study medications, 17 patients (59%) showed an EVR, only 3 (10%) however achieved a sustained virological response (SVR). SAMe and betaine were found to be safe when used with pegIFNα/ribavirin.

CONCLUSION

The addition of SAMe and betaine to pegIFNα/ribavirin improves early virological response in CHC.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00310336.

Antiviral activity of narlaprevir combined with ritonavir and pegylated interferon in chronic hepatitis C patients

Narlaprevir (SCH 900518) is a potent inhibitor of the hepatitis C virus (HCV) nonstructural protein 3 serine protease that is primarily metabolized by the cytochrome P450-3A4 system. In order to explore the use of ritonavir-based pharmacokinetic enhancement of an HCV protease inhibitor, this study investigated the safety, tolerability, pharmacokinetics, and antiviral activity of narlaprevir (with or without ritonavir) administered as monotherapy and as combination therapy with pegylated interferon-α-2b (PEG-IFN-α-2b) to HCV genotype 1-infected patients. This was a randomized, placebo-controlled, two-period, blinded study in 40 HCV genotype 1-infected patients (naïve and treatment-experienced). In period 1, narlaprevir was administered for 7 days as 800 mg three times daily without ritonavir or 400 mg twice daily with 200 mg ritonavir twice daily. In period 2, after a 4-week washout, the same dose and regimen of narlaprevir was administered in combination with PEG-IFN-α-2b for 14 days. Upon completion of period 2, all patients initiated PEG-IFN-α-2b and ribavirin treatment. A rapid and persistent decline in plasma HCV-RNA was observed in both treatment-experienced and treatment-naïve patients during period 1, with a mean viral load decline of at least 4 log₁₀ in all treatment groups. A high percentage of both treatment-experienced (50%) and treatment-naïve (≥ 60%) patients had undetectable HCV-RNA (< 25 IU/mL) after period 2. Standard of care resulted in sustained virological response (SVR) rates of 38% and 81% in treatment-experienced and treatment-naïve patients, respectively. Narlaprevir (with or without ritonavir) alone or in combination with PEG-IFN-α-2b was safe and well tolerated.

CONCLUSION

Narlaprevir administration resulted in a robust HCV-RNA decline and high SVR rates when followed by standard of care in both treatment-experienced and treatment-naïve HCV genotype 1-infected patients.

Management of untreated and nonresponder patients with chronic hepatitis C

Hepatitis C infection has evolved in the past quarter century from a newly recognized entity without a known pathogen (non-A, non-B hepatitis) to one of the world's most prevalent causes of liver disease, an important source for hepatocellular carcinoma, and the major indication for liver transplantation. It is caused by a virus with a complex replication cycle that occurs in multiple genotypes, of which the four most prevalent (1, 2, 3, and 4) exhibit differences in clinical behavior and responses to therapy. Chronic hepatitis C virus (HCV) in particular has evolved from a disease with no known treatment to one with several primary treatment options, none of which is uniformly effective, and a growing list of secondary treatment options for those who have failed to respond to, or relapsed after initial therapy. As treatment is often associated with significant side effects, it is now a disease that presents clinicians with multiple important decisions: whom to treat, when and with what to treat them initially, and how to manage patients who have failed during initial therapy to achieve a sustained virological response, the gold standard of effective therapy. This review examines each of these important decisions, presenting evidence to help guide clinicians in their choices. The decisions are addressed sequentially as they arise during the initial evaluation and subsequent treatment of a typical, newly recognized patient with chronic HCV, and the considerations facing the clinician when the patient has failed to achieve an SVR.

Meta-analysis: re-treatment of genotype I hepatitis C nonresponders and relapsers after failing interferon and ribavirin combination therapy

BACKGROUND

The efficacy of re-treating genotype I hepatitis C virus (HCV) patients who failed combination therapy with interferon/pegylated interferon (PEG-IFN) and ribavirin remains unclear.

AIMS

To quantify sustained virological response (SVR) rates with different re-treatment regimens through meta-analysis of randomized controlled trials (RCTs).

METHODS

Randomized controlled trials of genotype I HCV treatment failure patients that compared currently available re-treatment regimens were selected. Two investigators independently extracted data on patient population, methods and results. The pooled relative risk of SVR for treatment regimens was computed using a random effects model.

RESULTS

Eighteen RCTs were included. In nonresponders to standard interferon/ribavirin, re-treatment with high-dose PEG-IFN combination therapy improved SVR compared with standard PEG-IFN combination therapy (RR=1.49; 95% CI: 1.09-2.04), but SVR rates did not exceed 18% in most studies. In relapsers to standard interferon/ribavirin, re-treatment with high-dose PEG-IFN or prolonged CIFN improved SVR (RR=1.57; 95% CI: 1.16-2.14) and achieved SVR rates of 43-69%.

CONCLUSIONS

In genotype I HCV treatment failure patients who received combination therapy, re-treatment with high-dose PEG-IFN combination therapy is superior to re-treatment with standard combination therapy, although SVR rates are variable for nonresponders (≤18%) and relapsers (43-69%). Re-treatment may be appropriate for select patients, especially relapsers and individuals with bridging fibrosis or compensated cirrhosis.

Hepatitis C: viral and host factors associated with non-response to pegylated interferon plus ribavirin

Treatment for chronic hepatitis C virus (HCV) infection has evolved considerably in the last years. The standard of care (SOC) for HCV infection consists in the combination of pegylated interferon (PEG-IFN) plus ribavirin. However, it only induces a sustained virological response (SVR) in half of genotype 1-infected patients. Several viral and host factors have been associated with non-response: steatosis, obesity, insulin resistance, age, male sex, ethnicity and genotypes. Many studies have demonstrated that in non-responders, some interferon-stimulated genes were upregulated before treatment. Those findings associated to clinical, biochemical and histological data may help detect responders before starting any treatment. This is a very important issue because the standard treatment is physically and economically demanding. The future of HCV treatment would probably consist in the addition of specifically targeted antiviral therapy for HCV such as protease and/or polymerase inhibitors to the SOC. In genotype 1 patients, very promising results have been reported when the protease inhibitor telaprevir or boceprevir is added to the SOC. It increases the SVR rates from approximately 50% (PEG-IFN plus ribavirin) to 70% (for patients treated with a combination of PEG-IFN plus ribavirin plus telaprevir). Different elements are associated with non-response: (i) viral factors, (ii) host factors and (iii) molecular mechanisms induced by HCV proteins to inhibit the IFN signalling pathway. The goal of this review is to present the mechanisms of non-response, to overcome it and to identify factors that can help to predict the response to anti-HCV therapy.

Perspectives on fibrosis progression in hepatitis C: an à la carte approach to risk factors and staging of fibrosis

The morbidity and mortality of chronic hepatitis C is related to progressive fibrosis and the development of cirrhosis. The development of fibrosis in patients with HCV is highly influenced by immune status, host response to the virus and associated factors, such as, age, sex, alcohol intake, diabetes, obesity and coinfection with other viruses. The rate of fibrosis progression differs depending on several factors, including the stage of fibrosis and the time since infection. Routine assessment of fibrosis through biopsy every 3-5 years has poor patient acceptance and reliability, and might result in missed opportunities to improve or modify treatment priorities. Enhanced understanding of the pathophysiology of liver fibrosis in HCV infection has led to the development of a number of non-invasive assessment modalities. The ideal test would discriminate fibrosis in the categories none/early (stages 0/1), intermediate (stage 2) and advanced fibrosis/cirrhosis (stages 3/4) and be readily available, inexpensive and accurate. Biomarker tests utilize individual or combined serum markers to determine the degree of fibrosis. Other strategies combine biomarkers with clinical variables, such as patient age or utilize liver imaging or functional assessments. Incorporation of appropriately validated non-invasive assessments of liver fibrosis will likely improve the clinical care of patients with HCV infection.

Antifibrotic therapies: will we ever get there?

Progressive hepatic fibrosis is the final common pathway for most chronic liver injuries, leading to cirrhosis with risk of liver failure and hepatocellular carcinoma. It is now recognized that fibrosis is a dynamic process, and may be reversible prior to the establishment of advanced architectural changes to the liver. The most effective antifibrotic strategy is to cure the underlying disease process before advanced fibrosis has developed. Unfortunately, this is often not possible, and specific antifibrotic therapies are needed. Advances in the understanding of the pathogenesis of liver fibrosis have identified several potential novel therapeutic targets, but unfortunately clinical development has been disappointing. One major limitation has been the often prolonged natural history of fibrosis compared to experimental models, and difficulties in accurate noninvasive fibrosis assessment, thus making clinical trial design difficult. In this review, we highlight the most promising current antifibrotic strategies.

Re-treatment of children with chronic hepatitis C who did not respond to interferon-alpha treatment

BACKGROUND

Many patients with chronic hepatitis C do not respond to antiviral treatment. In adult patients the re-treatment of these patients has been extensively investigated. Because the response to re-treatment in children is not well defined we evaluated the efficacy and safety of interferon (IFN)-alpha plus ribavirin in patients who have failed to respond to previous treatment.

PATIENTS AND METHODS

In an open-label, uncontrolled study, 18 chronically infected children were investigated. Fifteen children had been treated with IFN-alpha plus ribavirin and 3 patients with IFN-alpha alone. Fourteen patients were nonresponders; 4 experienced viral breakthrough during treatment and/or relapse after treatment. Patients received IFN-alpha 3 times per week subcutaneously plus ribavirin for 48 weeks. Sixteen patients were infected with hepatitis C virus (HCV) genotype 1, 2 with genotype 4, and 1 with genotype 3 and co-infection with hepatitis B.

RESULTS

Four patients showed early viral response to therapy and became HCV-RNA negative after 12 weeks. Sustained viral response (HCV-RNA negative 6 months after end of treatment) was documented in 2 of them. These 2 patients belonged to the group of 4 children who relapsed or experienced a viral breakthrough during previous treatment. None of the 14 patients with prior nonresponse had sustained viral response.

CONCLUSIONS

Re-treatment with IFN-alpha plus ribavirin may be useful in children who relapsed in a previous antiviral treatment but seems not to be useful in nonresponders. These results are in line with studies from adult patients and should be therefore encouraged to provide a second chance for healing in a subgroup of patients.

Retreatment of hepatitis C patients with pegylated interferon combined with ribavirin in non-responders to interferon plus ribavirin. Is it different in real life?

BACKGROUND

More than 50% of hepatitis C viruses (HCV)-infected patients do not respond to the classical Interferon (IFN)/Ribavirin (RBV) combination therapy. The aim of this study was to evaluate the efficacy of retreatment with Peg-Interferon alpha-2b (PEG-IFN alpha-2b) plus RBV, in patients with HCV, genotypes 1 or 3, who were non-responders to the previous standard treatment with IFN/RBV.

METHODS

In the period 2005-2007, a total of 238 HCV chronic patients were non-responders to previous treatment with IFN plus RBV. Of these 130 agreed to be retreated with PEG-IFN alpha-2b and participated in this evaluation (90 with genotype 1 HCV and 40 with genotype 3 HCV). Patients were retreated at assisted IFN application hubs in compliance with the country's public health system rules. They received subcutaneous PEG-IFN alpha-2b, 1.5 microg, once weekly, associated with RBV, through the oral route, with doses determined according to weight (1,000 mg if weight <or= 75 kg and 1,250 mg if > 75 kg). Patients with genotype 1 HCV were retreated for over 48 weeks and patients with genotype 3 HCV for over 24 weeks. HCV-RNA was tested by polymerase chain reaction (PCR) at baseline, at week 12, at the end of the treatment, and 6 months thereafter. The predictiveness of week 12 in the development of a sustained virologic response (SVR) was also evaluated. Patients with negative HCV-RNA at week 12 were considered as early virologic responders (EVR).

RESULTS

EVR was observed in 25% of the patients with genotype 1 HCV and in 64% of the patients genotype 3 HCV (risk = 2.075 and p-value = 0.0414). SVR was observed in 22.2% of the patients with genotype 1 HCV and in 40% with genotype 3 HCV (intention-to-treat analysis). The positive predictive value (PPV) of the HCV-RNA testing at week 12, in order to obtain the SVR, was 65% for genotype 1 and 56% for genotype 3, and the negative predictive value (NPV) was 88% for genotype 1 and 89% for genotype 3.

CONCLUSIONS

PEG-IFN alpha-2b plus weight-based ribavirin is effective in re-treating previous interferon-alpha plus RBV failure; 22.2% of the patients with genotype 1 HCV and 40% of patients with genotype 3 HCV achieved SVR.

Does chemotherapy prevent HCV-related hepatocellular carcinoma? Cons

The accuracy and the reliability of well-recognized clinical, virologic, histologic, and molecular risk factors for hepatocellular carcinoma (HCC) are still insufficient. Thus, accurate risk prediction of cancer development in individual patients with the aim of selecting high risk cohorts of patients for HCC chemoprevention programs remains an elusive goal. Future directions in chemoprevention of HCC will be in the development of molecular risk models and of new chemopreventive agents. Studies examining multiple genes and proteins (genomics and proteomics) in the same HCCs will be required to evaluate this possibility thoroughly. A strategy aiming at preventing chronic liver disease of any etiology (HCV and HBV infection, alcohol, obesity, others) may be required to prevent HCC in low and intermediate incidence areas, and hence, worldwide. In the setting of secondary chemoprevention, literature data pooling suggests a slight preventive effect of interferon (IFN) on HCC development in patients with HCV-related cirrhosis. The magnitude of this effect is low, and the observed benefit might be due to spurious associations. The preventive effect is limited to sustained virological responders to IFN. So, there is no sound evidence to support a recommendation for widespread use of IFN to prevent HCC in HCV-related cirrhosis. In the setting of tertiary chemoprevention, the risk of recurrence of HCC may be reduced by IFN treatment in selected patient populations. Further large-scale multicenter randomized controlled trials may prove useful to evaluate the benefit on overall survival.

Pegylated Interferon and Ribavirin Dosing Strategies to Enhance Sustained Virologic Response

Hepatitis C virus (HCV) affects about 170 million people worldwide and is the most common chronic blood borne infection in the United States. Since the advent of blood screening protocols in the early 1990s, injection drug use has become the leading cause of infection. Hepatitis C can have both hepatic and nonhepatic manifestations of infection. Hepatic manifestations include hepatic fibrosis, cirrhosis, liver cancer, and liver failure. The standard treatment for chronic HCV is combination therapy with pegylated interferon-α and ribavirin. Although pegylated interferon and ribavirin has been used against HCV for close to a decade, advances in therapy have centered on doses and treatment durations. There has been increasing interest in applying on-treatment response or viral kinetics to predict antiviral response rates and shape therapeutic intervention. Protease inhibitors are a promising adjuvant to combination therapy, but their efficacy and safety are still under investigation.