Identifying hepatitis C virus genotype 2/3 patients who can receive a 16-week abbreviated course of peginterferon alfa-2a (40KD) plus ribavirin

Clinical Utility of a New Automated Hepatitis C Virus Core Antigen Assay for Prediction of Treatment Response in Patients with Chronic Hepatitis C

Hepatitis C virus core antigen (HCV Ag) is a recently developed marker of hepatitis C virus (HCV) infection. We investigated the clinical utility of the new HCV Ag assay for prediction of treatment response in HCV infection. We analyzed serum from 92 patients with HCV infection who had been treated with pegylated interferon and ribavirin. HCV Ag levels were determined at baseline in all enrolled patients and at week 4 in 15 patients. Baseline HCV Ag levels showed good correlations with HCV RNA (r = 0.79, P < 0.001). Mean HCV Ag levels at baseline were significantly lower in patients with a sustained virologic response (SVR) than in those with a non SVR (relapse plus non responder) based on HCV RNA analysis (2.8 log₁₀fmol/L vs. 3.27 log₁₀fmol/L, P = 0.023). Monitoring of the viral kinetics by determination of HCV RNA and HCV Ag levels resulted in similarly shaped curves. Patients with undetectable HCV Ag levels at week 4 had a 92.3% probability of achieving SVR based on HCV RNA assay results. The HCV Ag assay may be used as a supplement for predicting treatment response in HCV infection, but not as an alternative to the HCV RNA assay.

A Predictive Model for Selecting Patients with HCV Genotype 3 Chronic Infection with a High Probability of Sustained Virological Response to Peginterferon Alfa-2a/Ribavirin

Background

Access to direct-acting antiviral agents (DAAs) is restricted in some settings; thus, the European Association for the Study of the Liver recommends dual peginterferon/ribavirin (PegIFN/RBV) therapy wherever DAAs are unavailable. HCV genotype (GT) 3 infection is now the most difficult genotype to eradicate and PegIFN/RBV remains an effective option. The goal of this study was to devise a simple predictive score to identify GT3 patients with a high probability of achieving a sustained virologic response (SVR) with PegIFN alfa-2a/RBV therapy.

Methods

Relationships between baseline characteristics and SVR were explored by multiple logistic regression models and used to develop a simple scoring system to predict SVR using data from 1239 treatment-naive GT3 patients who received PegIFN alfa-2a/RBV for 24 weeks in two large observational cohort studies.

Results

The score was validated using a database of 473 patients. Scores were assigned for six factors as follows: age (years) (≤40: 2 points; >40 but ≤55: 1); bodyweight (kg) (<70: 2; ≥70 but <90: 1); no cirrhosis/transition to cirrhosis (2); ALT ≤2.5 x ULN (1); platelets (10⁹/L) (>200: 2; ≥100 but <200: 1); HCV RNA (<400,000 IU/mL: 1). The points are summed to arrive at a score ranging from 0‒10 where higher scores indicate higher chances of SVR; 141, 123, 203, 249, 232, and 218 patients had total scores of 0‒4, 5, 6, 7, 8, and 9–10, respectively, among whom SVR rates were 45%, 62%, 72%, 76%, 84%, and 89%. Among 622 patients who had scores of 6‒10 and HCV RNA <50 IU/mL by treatment week 4 the SVR rate was 86% (532/622).

Conclusions

A simple baseline scoring system involving age, bodyweight, cirrhosis status, ALT level, platelet count and HCV RNA level can be used to identify treatment-naive Caucasian patients with HCV GT3 infection with a high probability of SVR with PegIFN alfa-2a/RBV therapy.

The Usefulness of Defining Rapid Virological Response by a Very Sensitive Assay (TMA) during Treatment of HCV Genotype 2/3 Infection

The aim of this study was to determine in patients with HCV genotype 2 or 3 the performance at week 4 of two assays with different sensitivities for HCV RNA detection, for the prediction of SVR and stratification for treatment duration (14 and 24 weeks). Recruitment was from two trials comparing 14 and 24 weeks treatment to patients with rapid virological response (RVR) (n = 550). RVR was originally defined as HCV RNA <50 IU/ml at week 4. Patients with an available frozen plasma sample drawn at week 4 and with follow-up data week 24 post-treatment were included (n = 429). HCV-RNA was prospectively measured with COBAS Amplicor V2, Roche (CA) (lower detection limit 50 IU/ml) and retrospectively assessed with VERSANT HCV-RNA Qualitative Assay, Siemens (TMA) (lower limit detection 10 IU/ml). Genotype 3 was present in 80% and genotype 2 in 20%. A SVR was achieved in 82%. At week 4 HCV-RNA was undetectable in 74.8% and 63% of serum samples tested with CA and TMA, respectively. CA undetectable/TMA positive was observed in 61/341 (18%) of the samples. In genotype 3 patients a relapse was seen in 9% of the patients with both CA and TMA undetectable and in 25% of the patients who were CA undetectable/TMA positive (p = 0.006). In patients allocated to 14 weeks treatment a relapse was observed in 11% of TMA undetectable patients and 26% of TMA positive (p = 0.031). In genotype 2 patients treated for 14 weeks relapse was observed in 6% of the patients with both CA and TMA undetectable week 4. Assays with high sensitivity for HCV RNA identifies patients at week 4 with high risk of virological relapse. We recommend that patients with genotype 3 and detectable HCV RNA at levels below 50 IU/ml do not receive truncated therapy with pegIFN and ribavirin.

Biomarkers in HCV Infection

Liver-related biomarkers have been developed and validated mainly in patients with chronic hepatitis C for the prediction of liver fibrosis or cirrhosis, which is a final pathway of chronic liver injury. They are noninvasive, traceable, and easy-to-use. Biomarkers provide implications related to screening, diagnosis, treatment, and prognosis of chronic hepatitis. For the improvement of performance and coverage, biomarker panels, imaging biomarkers, and even genetic biomarkers have been developed. With the advancement of genomics and proteomics, earlier and more precise prediction is expected in the near future. In this review, multiple biomarker panels for the estimation of the degree of fibrosis in chronic hepatitis C, biomarkers for the screening and diagnosis of hepatitis C, biomarkers for the treatment of hepatitis C, biomarkers for the prediction of complications related to the chronic hepatitis C, and future perspectives will be summarized.

Evidence-based consensus on the diagnosis, prevention and management of hepatitis C virus disease

Hepatitis C virus (HCV) is a potent human pathogen and is one of the main causes of chronic hepatitis round the world. The present review describes the evidence-based consensus on the diagnosis, prevention and management of HCV disease. Various techniques, for the detection of anti-HCV immunoglobulin G immunoassays, detection of HCV RNA by identifying virus-specific molecules nucleic acid testings, recognition of core antigen for diagnosis of HCV, quantitative antigen assay, have been used to detect HCV RNA and core antigen. Advanced technologies such as nanoparticle-based diagnostic assays, loop-mediated isothermal amplification and aptamers and Ortho trak-C assay have also come to the front that provides best detection results with greater ease and specificity for detection of HCV. It is of immense importance to prevent this infection especially among the sexual partners, injecting drug users, mother-to-infant transmission of HCV, household contact, healthcare workers and people who get tattoos and piercing on their skin. Management of this infection is intended to eradicate it out of the body of patients. Management includes examining the treatment (efficacy and protection), assessment of hepatic condition before commencing therapy, controlling the parameters upon which dual and triple therapies work, monitoring the body after treatment and adjusting the co-factors. Examining the treatment in some special groups of people (HIV/HCV co-infected, hemodialysis patients, renal transplanted patients).

Hepatitis C virus genotype 3: a genotype that is not 'easy-to-treat'

The efficacy of antiviral treatment depends on which of the seven genotypes (G1-G7) of hepatitis C virus (HCV) has infected the patient. Conventionally, clinicians regarded G2 and G3 infections as 'easy-to-treat': dual therapy with pegylated interferon and ribavirin produces a sustained virologic response in approximately 40-50% of patients with G1 infection, compared with 80% when analyses report combined data for G2 and G3 patients, which is standard practice in many clinical studies. However, sustained virologic response rates appear to be lower in certain subgroups of people infected with G3 compared with those with G2 or the general HCV-infected population. This review examines the growing evidence that factors related to the virus (e.g., baseline viral load and a rapid virologic response) and host characteristics (e.g., steatosis and fibrosis, metabolic syndrome, host polymorphisms and ethnicity) contribute to variations in therapeutic success in G3 HCV.

OPERA: responses to peginterferon and ribavirin therapy in a subgroup of interferon-naïve patients with HIV/HCV genotype 2/3 co-infection in Italy

BACKGROUND & AIMS

Hepatitis C virus (HCV) genotype 3 (G3) is common among HIV/HCV co-infected individuals and associated with moderate sustained virological response (SVR) rates with pegylated interferon (PEG-IFN) plus ribavirin (RBV) therapy, while G2 is less frequent and associated with higher SVR. To determine SVR and other response rates, identify SVR predictors and analyse differences between G2 and G3 with PEG-IFN/RBV in a large HIV/HCV G2/3 patient population.

METHODS

This subgroup analysis of the prospective, observational OPERA (Optimized Pegylated interferon Efficacy and anti-Retroviral Approach) study was conducted between 2005 and 2011 in Italy in PEG-IFN/RBV-naïve HIV/HCV patients. The primary efficacy endpoint was SVR rate (HCV RNA <50 IU/ml or undetectable 24 weeks after end-of-treatment).

RESULTS

Five hundred and fifty-six HCV G2/3 patients (G2 n = 60; G3 n = 496) were treated with PEG-IFN alfa-2a 180 μg/week or PEG-IFN alfa-2b 1.5 μg/kg, + RBV 13.6 ± 2.3 (mean ± SD) mg/kg/day for median 47 (26-54) weeks. SVR rates were 57.7%, 68.3% and 56.5% for G2/3, G2 and G3 respectively) and RVR rates were 53.2%, 57.1% and 45.8% respectively. Independent SVR predictors were undetectable baseline HIV RNA [adjusted odds ratio (AOR), 2.64; 95% CI: 1.523-4.565, P = 0.0005], age (AOR 0.95 per year; 95% CI: 0.908-0.994, P = 0.0258) and anti-HCV treatment duration (AOR 1.034 per week; 95% CI: 1.013-1.057, P = 0.0019).

CONCLUSIONS

Undetectable HIV RNA, longer anti-HCV treatment adherence and younger age were independent SVR predictors in treatment-naïve HIV/HCV G2/3 patients receiving PEG-IFN/RBV. Suppressing HIV RNA replication before anti-HCV therapy and increasing adherence to PEG-IFN/RBV treatment SVR rates may improve SVR.

Optimal therapy of genotype-2 chronic hepatitis C: what's new?

The standard of care (SOC) for the treatment of HCV genotype 2 (HCV-2) was pegylated interferon alpha plus ribavirin (PEG-IFN/RBV) at weight-based doses for a response-guided duration. The launches of sofosbuvir and daclatasvir in 2014 have resulted in new, better tolerated and shorter treatment. The combination of sofosbuvir and RBV for 12 weeks appears to be the new SOC in both European and American guidelines. The cost and therefore the access to this treatment remains a problem in many countries because of major economic constraints. For the few more difficult-to-treat patients, a combination of direct acting antivirals may be suitable and is being studied in ongoing trials. Because of rapidly changing treatment recommendations, the decision to treat HCV-2 patients with currently approved drugs or to wait until a better option is available in the future, must be made according to the stage of fibrosis.

In routine clinical practice, few physicians use early viral kinetics to guide HCV dual therapy treatment decisions

BACKGROUND & AIMS

PROPHESYS is a large, multinational, non-interventional prospective cohort study of chronic hepatitis C patients treated with peginterferon alfa/ribavirin. This subanalysis assesses rates of premature treatment discontinuation stratified by on-treatment virological response (VR).

METHODS

This PROPHESYS subanalysis is restricted to treatment-naive, hepatitis C virus (HCV) genotype (G)1/2/3 mono-infected patients who received peginterferon alfa-2a (40KD)/ribavirin with intended treatment duration of 48 (G1) or 24 weeks (G2/3). Early virological responses were classified into four mutually exclusive categories [rapid VR (RVR), complete early VR (cEVR), partial EVR (pEVR), no RVR/EVR], using standard criteria.

RESULTS

The likelihood for shortening treatment owing to good efficacy was highest among patients with an RVR and HCV RNA≤400 000 IU/ml (G1 10.0%; G2/3 5.8%) whereas for poor efficacy, it was highest in G1 non-RVR/EVR patients with HCV RNA>400 000 IU/ml (56.6%). Factors significantly associated with early treatment discontinuation as a result of good efficacy in G1 patients included RVR vs. no RVR/EVR and, at baseline, lower HCV RNA, lower FIB-4 score, HCV infection via injection drug use. For G2/3 patients, factors included lower baseline HCV RNA and G2 vs. G3 infection. Most patients started with the recommended peginterferon alfa-2a dose, but a high proportion received a higher-than-recommended ribavirin dose.

CONCLUSIONS

Despite international guidelines, few physicians used early viral kinetics to abbreviate treatment. Therefore, relatively few patients with an RVR and low baseline HCV RNA abbreviated treatment. In addition, there were deviations in ribavirin starting doses, suggesting that physicians tailor treatment according to local guidelines or previous experience.

Treatment of chronic hepatitis C with pegylated interferon plus ribavirin in treatment-naïve 'real-life' patients in India

PURPOSE/AIM

Results of treatment of chronic hepatitis C (CHC) with pegylated interferon plus ribavirin (PEG-RBV) are mainly available from well-designed clinical trials, and only few 'real-life' studies which give a true picture of success of therapy are available. Such data in Indian patients is scarce. This prospective study aimed to evaluate the efficacy, safety, and factors associated with sustained virological response (SVR) in Indian CHC patients treated with PEG-RBV in 'real-life' setting.

MATERIAL AND METHODS

All treatment-naïve patients with CHC/compensated cirrhosis treated with PEG-RBV between January 2004 and December 2010 were included.

RESULTS

Of 592 patients started on treatment, 524 (88.5 %) completed therapy (mean ± SD age-42.0 ± 12.1 years; 74.3 % males). Genotype 3 (73.6 %) was the commonest, followed by genotype 1 (19.3 %). In intention to treat analysis, SVR rates for 'all' patients, genotype 1 and genotype 3 patients were 72.3 % (428/592), 57 % (65/114), and 78.2 % (341/436), respectively (in per-protocol analysis-81.7 %, 69.1 %, and 85.3 %, respectively). Noncirrhotics had better SVR rates compared to cirrhotics treated for the same duration. About 20 % patients had both low viral load and achieved rapid virological response (RVR). Factors significantly associated with SVR were age <40 years, absence of cirrhosis, RVR, and no reduction in interferon dose.

CONCLUSION

SVR rates in CHC patients treated in 'real-life' setting in India were better than those reported in western population. Therapy should be prolonged for patients with cirrhosis, while one-fifth of patients may qualify for abbreviated therapy. Factors significantly associated with SVR were age <40 years, absence of cirrhosis, RVR, and no reduction in interferon dose.

Immunotherapy of hepatocellular carcinoma with small double-stranded RNA

Background

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with limited therapeutic options. Since HCC has been shown to be immunogenic, immunotherapy is considered a promising therapeutic approach. Small interfering RNAs (siRNAs), depending on their structure and sequence, can trigger the innate immune system, which can potentially enhance the adaptive anticancer immune response in the tumor-bearing subjects. Immunostimulatory properties of nucleic acids can be applied to develop adjuvants for HCC treatment.

Methods

The transplantable HCC G-29 tumor in male CBA/LacSto (CBA) mice was used to study the effects of immunostimulatory RNA on tumor growth. Tumor size, metastases area in different organs of mice and mouse survival rate were analyzed. Furthermore the mouse serum IFN-α levels were measured using ELISA.

Results

In the present study, we found that a 19-bp RNA duplex (ImmunoStimulattory RNA or isRNA) with 3-nt overhangs at the 3′-ends of specific sequence displays immunostimulatory, antitumor, and antimetastatic activities in mice bearing HCC G-29. Our results demonstrate that isRNA strongly increases the level of interferon-α (IFN-α) by up to 25-fold relative to the level in mice injected with Lipofectamine alone (Mock), and to a lesser extent increases the level of proinflammatory cytokine interleukin-6 (IL-6) (by up to 5.5-fold relative to the Mock level), in mice blood serum. We showed that isRNA reliably (P < 0.05) inhibits primary tumor growth in mice compared to the mock group. Furthermore, injections of isRNA significantly enhanced necrotic processes in the center of the primary tumor, and decreased by twofold the width of the undifferentiated peripheral zone and the number of mitotic cells in this zone. The results showed that isRNA efficiently reduces the area of metastases in the liver, kidneys, and heart of CBA/LacSto mice with HCC.

Conclusions

The obtained results clearly demonstrate immunostimulatory and antimetastatic properties of the isRNAs in mice with HCC. Consequently, this short double-stranded RNA can be considered as a potential adjuvant for the therapy of HCC.

Review article: HCV genotype 3 – the new treatment challenge

BACKGROUND

Over the past several years, hepatitis C therapy has been pegylated interferon and ribavirin based. Although protease inhibitor-based therapy has enhanced response rates in genotype 1, the recent advances in therapy have demonstrated a challenge in genotype 3, a highly prevalent infection globally.

AIM

To provide a comprehensive summary of the literature evaluating the unique characteristics and evolving therapies in genotype 3.

METHODS

A structured search in PubMed, the Cochrane Library and EMBASE was performed using defined key words, including only full text papers and abstracts in English.

RESULTS

HCV genotype 3 is more prevalent in Asia and among intra-venous drug users. Furthermore, it interferes with lipid and glucose metabolism, and the natural history involves a more rapid progression of liver disease and a higher incidence of hepatocellular carcinoma (HCC). New therapies with protease inhibitors have focused on genotype 1 largely and have demonstrated enhanced responses, but have limited activity against genotype 3. Thus far, in clinical trials, NS5B and NS5A inhibitors have performed more poorly in genotype 3, while a cyclophilin inhibitor, alisporivir, has shown promise.

CONCLUSIONS

As treatments for HCV have evolved, genotype 3 has become the most difficult to treat. Furthermore, genotype 3 has special characteristics, such as insulin resistance and alterations in lipid metabolism, which may partly explain the lower treatment responses. A great deal of emphasis on advancing therapy is needed in this population that appears to have a more rapid progression of liver disease and a higher incidence of HCC.

Prediction of efficacy to pegylated interferon-α-2b plus ribavirin in patients with genotype 2 hepatitis C virus using viral response within 2 weeks

AIM

Rapid virological response (RVR), defined as serum hepatitis C virus (HCV) RNA negativity at 4 weeks, is the most useful predictor of sustained virological response (SVR) to standard pegylated interferon (PEG IFN) plus ribavirin therapy for patients infected with genotype 2 HCV. The aim of the present study was to predict SVR using viral response within 2 weeks of therapy initiation.

METHODS

Of 64 HCV genotype 2 patients with a high viral load treated with standard PEG IFN-α-2b plus weight-based ribavirin for 24 weeks, 58 patients whose adherence was more than 67% were analyzed. RNA and core antigen levels were measured at four time points: the day of therapy initiation, the following day, and at 1 and 2 weeks.

RESULTS

SVR was achieved in 73% (47/64) of patients. Univariate analysis of SVR contributing factors showed significant differences with age, bodyweight, white blood cell count, platelet count, fibrosis marker levels, baseline core antigen level and viral response. The area under the receiver-operator curve (AUC) of the core antigen level at 1 week (AUC, 0.940) was the highest among the significant SVR predicting factors. Setting 100 fmol/L as the cut-off value for core antigen level at 1 week, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy for predicting SVR were 100%, 86%, 96%, 100% and 97%, respectively, and for predicting RVR were 66%, 93%, 97%, 46% and 72%, respectively.

CONCLUSION

The HCV core antigen level at 1 week after therapy initiation is the most useful predictor for SVR.

Is 3 the new 1: perspectives on virology, natural history and treatment for hepatitis C genotype 3

Affecting 2-3% of the world's population, hepatitis C is a common viral infection which is a significant cause of morbidity and mortality. Hepatitis C genotype 1 is the dominant viral genotype among Western patients. For the last 20 years, in the era of interferon-based therapy, it was far more difficult to treat relative to genotypes 2 and 3. Accordingly, a significant focus of research was on new antiviral agents for the dominant genotype 1 patient. Now, as promising specific treatments are being introduced for genotype 1, the attention of clinicians and researchers has turned back to the 50-70 million patients infected with a nongenotype 1 hepatitis C. Furthermore, after recent, larger randomized trials, we have realized that genotype 2 is truly interferon sensitive while genotype 3 patients are far less successful with therapy. In this fundamentally altered landscape, genotype 3 is now potentially the most difficult to treat genotype and an area of intense research for new drug development. Herein we review the virology, natural history and the treatment of genotype 3 hepatitis C.

Therapy of chronic hepatitis C virus infection in the era of direct-acting and host-targeting antiviral agents

OBJECTIVES

Chronic hepatitis C virus (HCV) infection represents a leading worldwide medical and social problem. The expanding knowledge of HCV lifecycle has led to the development of novel antiviral agents that: a) specifically target a viral function (direct-acting antivirals), or b) specifically inhibit viral replication. The present review describes the novel anti-HCV drugs that have been better studied at the time of this writing and the current two types of treatment, namely interferon-based and interferon-free regimens. In addition, predictive factors, virological responses, side-effects, and resistance mechanisms of the novel agents are summarized.

CONCLUSIONS

The introduction of novel antiviral agents is remarkably changing the therapeutic combinations aimed at improving virological responses both for easy-to-cure and difficult-to-treat patients. Since additional, effective drugs are under advanced development, it seems reasonable to expect that further therapeutic and prognostic improvements will be achieved in the near future.

Treatment of hepatitis C: how will we use viral kinetics, response-guided therapy?

Hepatitis C virus (HCV) RNA level monitoring is currently used to guide the duration of interferon-containing treatment regimens. Nowadays, HCV RNA level quantification is based on real-time polymerase chain reaction assays that are both sensitive and accurate. Assessing the virological response to therapy is used to shorten treatment duration in early responders, in order to reduce the cost and burden of adverse events of therapy without impacting the chance of success. Whether response-guided therapy will still be useful in the era of all-oral, interferon-free regimens remains uncertain.

A new era in the treatment of chronic hepatitis C infection

Treatment of chronic hepatitis C virus (HCV) infection has evolved over the past three decades. At the start, treatment involved interferon monotherapy followed by combination therapy using interferon and ribavirin, and subsequently evolved to pegylated interferon (Peg-IFN) and ribavirin. In genotype 1 infection, rates of sustained virological response (SVR) are approximately 45 % with Peg-IFN and ribavirin, whereas SVR rates in genotypes 2 and 3 infections are as high as 70 % to 80 %. Side effects and cost related to these drugs are important concerns, particularly in countries like India where patients have to bear their health expenses. In the recent past, there has been a significant change in course with the on-going search and the development of more effective drugs in the management of HCV infection. Telaprevir and Boceprevir are two new potent protease inhibitors (direct acting antiviral or DAA agents) which, when administered with Peg-IFN and ribavirin, have shown to result significantly higher SVR rates in phase 3 studies in patients with genotype 1 infection, both in treatment naïve patients (up to 75 %) and those with previously failed therapy. Several other new antiviral agents some in combination with Peg-IFN and ribavirin and some in combination without Peg-IFN (IFN-free regimens) are currently being tested in patients with genotype 1, 2 and 3 infections and are expected to dramatically change the armamentarium of HCV therapy in the coming years.

Update on the treatment of patients with non-genotype 1 hepatitis C virus infection

Current treatment for patients with non-genotype 1 hepatitis C virus infection consists of pegylated interferon plus ribavirin for 24 weeks, which leads to sustained virologic response (SVR) rates of 65%-80%. In the United States, the ribavirin dose for genotypes 2 and 3 is 800 mg/day. However, the use of weight-based ribavirin allows for the potential to shorten the duration of treatment from 24 to 12-14 weeks without reducing SVR rates in individuals who have undetectable viral loads at treatment week 4 and do not have severe liver disease. For patients who are still viremic at week 4, treatment durations even longer than 24 weeks are advised in Europe. In addition, accumulating evidence shows that for patients with unfavorable baseline characteristics, using weight-based ribavirin may increase SVR. In patients who do not achieve SVR with ribavirin 800 mg/day for 24 weeks, retreatment with weight-based ribavirin should be considered. The impact of new molecules in development will be discussed.

Effectiveness of alpha interferon (+ ribavirin) in the treatment of chronic viral hepatitis C genotypes 2 and 3 in a Brazilian sample

CONTEXT

Pharmacovigilance studies aim to detect, assess, understand and prevent risks of adverse effects of medications or any other possible drug related problem. Alpha interferon is being produced by Bio-Manguinhos/Fiocruz, Rio de Janeiro, RJ, Brazil and used in the treatment of chronic hepatitis C at Brazilian National Health System.

OBJECTIVE

To study the safety profile and effectiveness of alpha interferon in a sample of Brazilian patients with chronic hepatitis C genotypes 2 and 3, in Porto Alegre, RS, Brazil.

METHOD

We followed a cohort of chronic hepatitis C genotypes 2 and 3 patients treated with alpha interferon plus ribavirin in a specialized outpatient clinic in southern Brazil. Adverse events were collected and classified according to severity in monthly structured interviews. To measure effectiveness, hepatitis C viral load was evaluated before, at the end and 24 weeks after the treatment.

RESULTS

We followed 141 patients during the study period, of which 52.5% were female with mean age of 52 years. The most frequent adverse events were fatigue (84%), headache (79%) and myalgia (75%). There were 13 treatment interruptions due to adverse events, 9 of those considered serious adverse events. Virological response at end of treatment was 54.6% and after 24 weeks 39.7%, considering all patients who started treatment.

CONCLUSION

The product produced by Bio-Manguinhos has similar efficacy and adverse event and sustained virological response profiles comparable to those found in the literature. This is the first study of pharmacovigilance performed with the Brazilian product. These data will be useful for planning and management of this disease in Brazil.

Virology of hepatitis C virus infection

The multiple steps of the HCV lifecycle have been recently unravelled, thanks to the development of a number of cell-free or cell culture-based model systems. The HCV lifecycle offers a very large number of potential targets of intervention for specific anti-HCV drugs, including direct-acting antiviral drugs and host-targeted agents. HCV virological tools include enzyme immunoassays (EIAs) that detect anti-HCV antibodies and detect/quantify HCV core antigen, and molecular biology-based assays that are used to detect and quantify HCV RNA and to determine the HCV genotype. Recently, point-of-care tests and alternatives to laboratory tests that require whole-blood samples have been developed to improve access to screening, diagnosis and care. Virological tools are used in clinical practice to diagnose acute and chronic HCV infection, to decide who should be treated, to select the optimal therapy and to monitor treatment responses in order to tailor treatment duration.

Steatosis is the predictor of relapse in HCV genotype 3- but not 2-infected patients treated with 12 weeks of pegylated interferon-α-2a plus ribavirin and RVR

HCV genotypes 2- or 3-infected patients with a rapid virological response (RVR) to therapy with pegylated interferon and ribavirins who have a low viral load, noncirrhotic and nonobese may be considered for a shorter course of treatment. However, no studies have assessed host-viral factors associated with relapse in genotype 2 and 3 separately. Accordingly, we assessed whether 12 weeks of pegylated interferon and ribavirin was an optimized regimen for treatment of HCV genotype 2 and 3 with positive predictors of response. Power and sample size were a priori calculated and 96 consecutive chronic hepatitis C patients (53, genotype 2 and 43, genotype 3) without cirrhosis who were not obese and who achieved a RVR to therapy with peg-IFN-α-2a and ribavirin were enrolled. Fibrosis, steatosis, homeostatic model assessment-insulin resistance and HCV RNA were predefined variables to be evaluated in relapse. An intention-to-treat analysis was performed. SVR rates were 98% and 84% for genotype 2 and 3, respectively. Analysis of genotype 3 patients who had relapse showed a negative correlation with steatosis (P < 0.0001) and HCV RNA (P < 0.015). Multivariate analysis showed that steatosis was the independent predictor of relapse (OR, 0.988; 95% CI, 0.981-0.993; P < 0.001). Genotype 3 patients with steatosis had a relapse rate of 36.4% and 15.8% in those with high and low viral load, respectively, whereas there was no relapse in those without steatosis. In conclusion, a 12-week course of therapy is sufficient for patients without cirrhosis, not obese and infected with HCV genotype 2 achieve a RVR. This is not the case for genotype 3. Steatosis is the independent predictor of relapse. New therapeutic strategies are necessary for this subgroup of HCV genotype 3.

Boceprevir: a novel nonstructural 3 (NS3) protease inhibitor for the treatment of chronic hepatitis C infection

Chronic hepatitis C infection is a leading cause of morbidity and mortality worldwide, with hepatitis C related cirrhosis being the most common indication for transplant and a major cause for the increase in hepatocellular carcinoma worldwide. Treatment for hepatitis C has consisted of nonspecific immunomodulatory therapies that stimulate the immune system and inhibit hepatitis C replication. Pegylated (peg-)interferon and ribavirin have been the standard of care with an overall sustained response rate of 40-50% in patients with genotype 1 infection, and 80% in genotype 2 or 3. Recently, direct-acting antiviral agents, including boceprevir, have demonstrated improved sustained response rates in patients with genotype 1 infection when given in combination with interferon and ribavirin. Boceprevir is a structurally novel hepatitis C virus (HCV) nonstructural 3 (NS3) protease inhibitor that has demonstrated robust antiviral activity in HCV replicons. Clinically, in phase II and III trials, boceprevir 800 mg three times daily with peginterferon and ribavirin has led to improved sustained response rates in genotype 1 infection treatment-naive patients, relapsers, partial responders, and null responders. Phase II data have demonstrated that ribavirin is essential for optimal boceprevir response. Moreover, phase II data have suggested that a 4-week peginterferon or ribavirin lead-in strategy may reduce relapse rates and provide crucial on-treatment data for treatment response with boceprevir addition. Side effects of boceprevir when added to peginterferon and ribavirin are similar to peginterferon and ribavirin, though higher rates of anemia have been noted, with an incremental increase in erythropoietin use. The addition of boceprevir represents a major advance in patients with genotype 1 infection who are treatment naïve.

The COBAS ® TaqMan ® hepatitis C virus assays: automated systems for accurate and sensitive viral load quantification

In recent years, the real time-based TaqMan(®) technology has allowed the development of highly sensitive hepatitis viral load tests with broad dynamic ranges. The increasing applications of these tests in clinical diagnostics have shown the utility of viral load as a predictive marker of treatment response and proven its key role in invidualized antiviral therapies. Future refinement in viral load assays, including higher sensitivity, genotype inclusivity, standardization and automation, will further foster the concept of personalized healthcare in the clinical management of chronic hepatitis C.

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.

What's new in HCV genotype 2 treatment

Genotype 2 (HCV-2) accounts for 8% of the patients with chronic hepatitis C virus in Europe. Because of the favourable response to interferon (IFN)-based treatment, this group is considered an 'easy-to-treat' genotype along with HCV-3. However, experimental and clinical data suggest possible differences between HCV-2 and -3. Recently, subtle differences in treatment efficacy have also been shown in response-guided treatment studies. In these studies, the duration of pegylated interferon (PEG-IFN) and ribavirin (RBV) treatment was tailored according to treatment response. Although SVR rates were similar between HCV-2 and HCV-3 patients after a rapid virological response (RVR), in the absence of RVR, the rates were lower in HCV-3 than in HCV-2. The triple combination treatment, including direct-acting antivirals (DAA) that will be commercialized in the coming months might increase SVR rates in this particular subgroup of patients. According to existing results, telaprevir might be beneficial in HCV-2 but not in HCV-3 patients. A nucleotide analogue polymerase inhibitor, PSI-7977 by Pharmasett has been shown to be active against both. The role of the IL28B polymorphism as a predictor of response to the current standard of care (SoC), PEG-IFN and RBV treatment is the subject of debate, but this mainly seems to be because of the small size of the samples in the studies performed so far. Existing results suggest that the genetic evaluation of IL28B may be useful in patients with HCV-2 for predicting response in patients without RVR.

Response to peginterferon-alfa 2b and ribavirin in Japanese patients with chronic hepatitis C genotype 2

BACKGROUND

The current standard treatment for patients infected with hepatitis C virus (HCV) of genotype 2 is the combination of peginterferon (PEG-IFN) plus ribavirin (RBV) for 24 weeks.

AIMS

We assessed the sustained virological response (SVR) rates in HCV genotype 2-infected Japanese patients in relation to the duration of treatment.

METHODS

Between 2006 and 2009, among 147 patients with HCV genotype 2-infection in Chiba Prefecture, 138 consecutive patients were finally enrolled. Twenty-one, 97 and 20 patients were treated with PEG-IFN-alfa 2b plus RBV for 16, 24 and 48 weeks, respectively. Epidemiological data and treatment outcomes were retrospectively evaluated. HCV RNA was measured with COBAS AMPLICOR HCV Monitor Test v. 2.0.

RESULTS

The overall SVR rate was 82.6% (114 of 138): treatment-naïve patients, 86.4% (89 of 103); patients with history of previous treatment, 71.4% (25 of 35). Patients treated for 16, 24 and 48 weeks obtained SVR rates of 66.6% (14 of 21), 86.5% (84 of 97) and 80.0 (16 of 20), respectively.

CONCLUSIONS

The SVR rates of PEG-IFN-alfa 2b plus RBV in Japanese patients were similar to those in previous studies. Combination treatment for 24 weeks for some patients infected with HCV genotype 2 may be superior to that for 16 weeks. More precise patient selection will be needed to shorten the combination treatment.

Response-guided peg-interferon plus ribavirin treatment duration in chronic hepatitis C: meta-analyses of randomized, controlled trials and implications for the future

Response-guided pegylated interferon (peg-IFN) plus ribavirin (P/R) therapy trials on genotype (G)1 and G2/G3 hepatitis C virus-infected patients provide contradictory results. We conducted meta-analyses of randomized, controlled trials to address (1) the benefit of a 72-week extended-duration therapy in G1-slow responders and (2) adequate shortened duration therapy in G1 and G2/G3-rapid responders. Seventeen trials were selected, including 624 G1 rapid responders, 570 G1 slow responders, and 2,062 G2/G3 rapid responders. Virologic outcomes and treatment discontinuation data were collected from published articles and by asking investigators. Pooled estimates of sustained virologic response (SVR), relapse, and dropouts were calculated using the random effects model, considering the variability of shortened duration, ribavirin dose, genotype, and baseline viral load. In G1 slow responders, a 72-week extended duration increased SVR (+10.7%; 95% CI [confidence interval]: +4.4% to + 17.1%), decreased relapse (-12.3%; 95% CI: -25.4% to 0%), and did not significantly increase drop-out rates (+4.5%; 95% CI: -0.6% to + 9.6%). The benefit of extended duration was lower when using a weight-based ribavirin regimen (+8.7%; 95% CI: +1.7% to + 15.8%). In G1 rapid responders, a 24-week shortened duration decreased SVR (-12.5%; 95% CI: -19.2% to -5.8%) and increased relapse rates (+8.8%; 95% CI: +2.9% to + 14.8%). Such differences were not significant in patients with baseline viral load <400,000 UL/mL (-4.4%; 95% CI: -9.8% to + 1%). In G2/G3 rapid responders, SVR was more common for standard 24-week duration than for shortened durations (+4.1%; 95% CI: +0.1% to + 8.5), but this benefit was not significant when ribavirin was weight-adjusted and the short duration was 16 weeks (-1.7%; 95% CI: -6.1% to + 2.7%) and for G2 patients (+1.6%; 95% CI: -0.2% to + 5.5%).

CONCLUSION

Long durations of P/R therapy improve SVR, regardless of genotype. This effect is nonetheless negligible in rapid responders, with the most favorable conditions for SVR (G2, G1 with low viral load, and G3 with weight-adjusted ribavirin regimen).

Telaprevir alone or with peginterferon and ribavirin reduces HCV RNA in patients with chronic genotype 2 but not genotype 3 infections

BACKGROUND & AIMS

We evaluated antiviral activity of 2 weeks therapy with telaprevir alone, peginterferon alfa-2a and ribavirin (PR), or all 3 drugs (TPR) in treatment-naïve patients with chronic hepatitis C virus (HCV) genotype 2 or 3 infections.

METHODS

We performed a randomized, multicenter, partially blinded study of patients (23 with HCV genotype 2, 26 with genotype 3) who received telaprevir (750 mg every 8 h), placebo plus PR (peginterferon, 180 μg, once weekly and ribavirin, 400 mg, twice daily), or TPR for 15 days, followed by PR for 22 or 24 weeks. Plasma levels of HCV RNA were quantified.

RESULTS

Levels of HCV RNA decreased in all patients with HCV genotype 2, including those who received telaprevir monotherapy. The decrease was more rapid among patients who received telaprevir. By day 15, 0% (telaprevir), 40% (TPR), and 22% (PR) of patients with HCV genotype 2 had undetectable levels of HCV RNA; rates of sustained virologic response were 56%, 100%, and 89%, respectively. Overall, 6 of 9 HCV genotype 2 patients that received only telaprevir had viral breakthrough within 15 days after an initial response. HCV RNA levels decreased slightly among patients with HCV genotype 3 who received telaprevir and decreased rapidly among patients given PR or TPR (telaprevir had no synergistic effects with PR). Sustained virologic response rates were 50%, 67%, and 44% among patients given telaprevir, TPR, or PR respectively; 7 patients with HCV genotype 3 relapsed after therapy (2 given telaprevir, 3 given TPR, and 2 given PR) and 3 patients with HCV genotype 3 had viral breakthrough during telaprevir monotherapy. The incidence of adverse events was similar among groups.

CONCLUSIONS

Telaprevir monotherapy for 2 weeks reduces levels of HCV RNA in patients with chronic HCV genotype 2 infections, but has limited activity in patients with HCV genotype 3.

Individualizing treatment duration in hepatitis C virus genotype 2/3-infected patients

The drugs currently licensed for the treatment of hepatitis C are Peg-Interferon (PEG-IFN) and ribavirin. In recent years, the recommendation to treat hepatitis C virus genotype 2- and 3-infected patients with a fixed 800 mg/day dose of ribavirin in combination with PEG-IFN and for just 24 weeks has been challenged by the concept of tailoring the length of therapy according to on-treatment viral response. Therefore, the objective of the present review was to highlight the different designs of the studies on short treatment duration and the role of wk4-R as a predictor of sustained virological response after an abbreviated course of treatment. The secondary aim was to verify whether we had enough evidence to support the implementation of a short treatment course in subsets of patients with genotype 2 and 3 infection. We will also focus on how drug dosing may have influenced the outcome of treatment. To clarify reasons for discrepant results in the studies so far published, the recently discovered genetic variant near the interleukin 28B gene will be presented and its predictive role will be discussed. Finally, we will face the debated issue of whether the subset of patients with genotype 2 or 3 requires an extended treatment duration.

Optimal therapy in hepatitis C virus genotypes 2 and 3 patients

Current guidelines recommend that patients with genotype 2 (G2) and 3 (G3) chronic hepatitis C be treated with pegylated interferon (PEG-IFN) plus low doses of ribavirin (800 mg/day) for 24 weeks, resulting in a sustained virological response (SVR) rate of approximately 80%. Considering these high response rates, several recent randomized trials have assessed whether shorter treatment (12-16 weeks) could be cost-effective in these patients. The results of these studies vary but suggest better responsiveness in G2 patients, and overall, do not strongly support reducing treatment to <24 weeks in all patients. On the other hand, the presence of a rapid virological response (RVR) (defined as an undetectable hepatitis C virus-RNA at 4 weeks of treatment) was always reported to be the best positive predictor of achieving SVR in both G2 and G3 patients. These results suggest that in a subgroup of subjects with RVR (G2>G3, viral load <400,000 IU, low fibrosis, no metabolic cofactors), shorter treatment is as effective as standard regimens, and that it can be proposed mainly if problems of poor tolerance or adherence are foreseen. It is possible that the SVR rate in non-RVR patients and non-responder patients could also be improved by prolonging therapy, but this must be specifically investigated in other studies along with the role of IL28B polymorphisms.

How to use virological tools for the optimal management of chronic hepatitis C

Approximately 180 million individuals are chronically infected with hepatitis C, which is strongly associated with the development of cirrhosis, end-stage liver disease and hepatocellular carcinoma. Several virological tools (anti-HCV antibody assays, measurement of HCV-RNA, HCV-genotyping) are useful in management of hepatitis C infected patients. The primary goal of antiviral therapy in chronic hepatitis C is a sustained virological response (SVR). The HCV genotype should be determined in every patient considered for antiviral therapy because the currently recommended treatment duration and ribavirin doses differ among HCV genotypes. Exact subtyping might gain increased importance for future therapies with direct-acting antiviral agents (DAA) because of differences of antiviral activities and barriers to resistance among HCV subtypes. Monitoring HCV RNA by a highly sensitive assay (LOD ≤ 15 IU/ml) is the basis for management of response guided therapy of chronic hepatitis C with pegylated IFN plus ribavirin. Rules for early discontinuation of antiviral therapy in non-responders and determination of optimal treatment durations in virologic responders have been developed for application of individualized treatment strategies.

Virological tools to diagnose and monitor hepatitis C virus infection

Approximately 200 million people are chronically infected with hepatitis C virus (HCV). Infection with HCV is curable by therapy, with the current standard treatment based on the combination of pegylated interferon-α and ribavirin. Viral eradication is achieved in approximately half of treated patients. In 2011 a new antiviral treatment based on a triple combination with a protease inhibitor will become available. Virological tools are essential to diagnose HCV infection but they have found their principal application in guiding treatment decisions and assessing the virological responses to therapy. These include the anti-HCV antibody assay, measurements of HCV core antigen and HCV viral load and HCV genotyping. The HCV RNA can be ideally assayed by a real-time assay with a limit of detection of 10-15 IU/mL. Monitoring of viral kinetics during the early phases of antiviral treatment is crucial in making treatment decisions such as early stopping rules and also in optimizing the treatment duration. The HCV genotype should be assessed before the start of treatment because it determines the treatment length and ribavirin dose and also offers prognostic information on treatment outcomes as certain genotypes respond more favourably to treatment.

Evolution of interferon-based therapy for chronic hepatitis C

Since 1986, interferon-alfa (IFN-α) monotherapy has been administered for patients with chronic hepatitis C (CHC). However, sustained response rate is only about 8% to 9%. Subsequent introduction of ribavirin in combination with IFN-α was a major breakthrough in the treatment of CHC. Sustained virological responses (SVRs) rate is about 30% in hepatitis C virus genotype 1 (HCV-1) patients, and is about 65% in HCV-2 or -3 patients. After 2000, pegylated interferon (PegIFN) much improved the rates of SVR. Presently, PegIFN-α-ribavirin combination therapy has been current standard of care for patients infected with HCV. In patients with HCV-1, treatment for 48 weeks is optimal, but 24 weeks of treatment is sufficient in HCV-2 or -3 infected patients. Clinical factors have been identified as predictors for the efficacy of the IFN-based therapy. The baseline factor most strongly predictive of an SVR is the presence of HCV-2 or -3 infections. Rapid virological response (RVR) is the single best predictor of an SVR to PegIFN-ribavirin therapy. If patients can't achieve a RVR but achieve a complete early virological response (cEVR), treatment with current standard of care can provide more than 90% SVR rate. HCV-1 patients who do not achieve an EVR should discontinue the therapy. Recent advances of protease inhibitor may contribute the development of a novel triple combination therapy.

Cost effectiveness and quality of life considerations in the treatment of hepatitis C infection

Chronic hepatitis C1 is a common cause of liver disease worldwide. It is a slow and progressive condition which can lead to decompensated cirrhosis and hepatocellular carcinoma. Hepatitis C virus1 impairs quality of life (QOL) even in the absence of chronic liver disease, but its relative silent nature can lead to a delay in diagnosis. The current standard of care of treatment is pegylated interferon and ribavarin. This achieves a sustained virological response (SVR), which is a cure of infection, in up to 80% of patients depending on viral genotype. The attainment of SVR improves survival, avoids long-term complications, and improves QOL. But treatment is not only expensive; there are issues of tolerability and adverse effects. This has led to a multitude of cost effective analysis and health technology assessment on HCV treatment. This overview discusses the natural history of the virus infection and its effect on the patients’ QOL. It focuses on the treatment options available, their efficacy, and cost effectiveness. It reviews the evaluations that suggest combination therapy is cost effective and explores the assumptions and limitations of these studies in real world treatment arenas.

Individualisation of antiviral therapy for chronic hepatitis C

The combination of pegylated-interferon (PEG-IFN)/ribavirin is currently the standard of care antiviral treatment for chronic hepatitis C (CHC), but optimal results require an individual approach. Key issues are to deliver doses that confer optimal antiviral efficacy against hepatitis C virus (HCV) for a time sufficient to minimise relapse. Viral monitoring during therapy guides the subsequent treatment course, particularly HCV RNA results at 4 weeks (rapid viral response [RVR]) and 12 weeks (complete early viral response [cEVR]). There is strong evidence that for most patients with genotypes 2 or 3 HCV infection, RVR allows truncation of treatment to 16 weeks, provided ribavirin dose is weight-based. However, those patients with cirrhosis, insulin resistance/diabetes or older than 50 years need 6-12 months treatment. For "difficult-to-treat" CHC (genotypes 1 and 4), RVR is infrequent (approximately 15% in European studies), but allows treatment to be truncated from 48 to 24 weeks. Without RVR, there is some evidence that longer treatment (72 weeks) improves sustained viral response (SVR). However, "induction dosing" first 12 weeks of PEG-IFN clearly does not improve SVR. To prevent dose reductions and complete therapy, it is critical to detect and treat depression and other disabling side-effects, including judicious use of growth factors for severe anemia or neutropenia and possibly, thrombocytopenia. Another potentially important aspect may be attempts to counter central obesity and insulin resistance, which confer suboptimal antiviral response with any HCV genotype. Treatment partnerships with specialist nurses, psychological therapists and other healthcare workers are also essential for optimal individual management of patients with CHC.

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.

Definition of rapid virologic response with a highly sensitive real-time PCR-based HCV RNA assay in peginterferon alfa-2a plus ribavirin response-guided therapy

BACKGROUND & AIMS

Assessing hepatitis C virus (HCV)-RNA levels is integral to response-guided therapy. Rules for early discontinuation and determination of treatment duration were mainly established with HCV-RNA assays with a detection limit of 50IU/ml (COBAS Amplicor HCV [CA]). The currently used real-time PCR-based COBAS Ampliprep/COBAS-TaqMan HCV (CAP-CTM) test has a detection limit of approximately 10IU/ml. It is unknown whether shortening of treatment duration to 16/24 weeks in patients with rapid virological response at week 4 (RVR) and viral loads between 10 and 50IU/ml is possible.

METHODS

We reanalysed stored serum from two large, multinational, randomized trials in which patients were treated with peginterferon alfa-2a/ribavirin (n=962). Results of CAP-CTM with truly undetectable HCV RNA and those <15IU/ml, which includes patients with residual viraemia (<15), were compared with the originally obtained results using the CA assay.

RESULTS

RVR rates were comparable for CA (<50) and CAP-CTM (<15) with 32% and 32% for genotype (gt) 1 and 50% and 49% for gt2/3 patients, respectively. A significantly smaller number of samples really had truly undetectable HCV RNA by the CAP-CTM assay (24% for gt1, 37% for gt2/3). However, sustained virological response rates after shortened treatment (16/24weeks) were not significantly different in patients with a RVR <50, a RVR <15 and RVR undetectable (82%, 83%, 83% for 24weeks gt1 and 95%, 95%, 94% for 16weeks gt2/3).

CONCLUSIONS

Shortening the treatment duration to 16/24weeks can be performed on the basis of a RVR with HCV-RNA concentrations <15IU/ml by the CAP-CTM assay.