Meta-analysis: a randomized trial of peginterferon plus ribavirin for the initial treatment of chronic hepatitis C genotype 4

Effectiveness of ravidasvir plus sofosbuvir in interferon-naïve and treated patients with chronic hepatitis C genotype-4

BACKGROUND & AIMS

Although treatment of hepatitis C virus (HCV) and HCV-genotype-4 (GT4) has become very effective, it remains very expensive, and affordable options are needed, especially in limited resource countries. The aim of this study was to assess the efficacy and safety of the combination of ravidasvir (an NS5A inhibitor) and sofosbuvir to treat patients with chronic HCV-GT4 infection.

METHODS

A total of 300 patients with HCV-GT4 infection were recruited in three groups: treatment-naïve patients with or without compensated Child-A cirrhosis (Group 1); interferon-experienced patients without cirrhosis (Group 2); and interferon-experienced patients with cirrhosis (Group 3). Groups 1 and 2 received ravidasvir 200 mg QD plus sofosbuvir 400 mg QD for 12 weeks and were randomized 1:1 to treatment with or without weight-based ribavirin. Group 3 patients received ravidasvir plus sofosbuvir with ribavirin and were randomized 1:1 to a treatment duration of 12 weeks or 16 weeks. The primary endpoint was sustained virologic response at 12 weeks post-treatment (SVR12).

RESULTS

A total of 298 patients were enrolled: 149 in Group 1, 79 in Group 2 and 70 in Group 3. SVR12 was achieved in 95.3% of all patients who started the study, including 98% of patients without cirrhosis and 91% of patients with cirrhosis, whether treatment-naïve or interferon-experienced. Ribavirin intake and history of previous interferon therapy did not affect SVR12 rates. No virologic breakthroughs were observed and the study treatment was well tolerated.

CONCLUSIONS

Treatment with ravidasvir plus sofosbuvir, with or without ribavirin, was well tolerated and associated with high sustained virologic response rate for HCV-GT4 infected patients with and without cirrhosis, regardless of previous interferon-based treatments.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Identifier: NCT02371408.

LAY SUMMARY

This study evaluated efficacy and safety of the new oral hepatitis C drug ravidasvir in combination with the approved oral drug sofosbuvir in 298 patients infected with hepatitis C type 4. Our results showed that treatment with ravidasvir plus sofosbuvir, with or without ribavirin, was well tolerated and associated with high response rate in patients with and without cirrhosis.

Viral and host factors associated with outcomes of hepatitis C virus infection (Review)

Hepatitis C virus (HCV) infection is a major health issue globally. Owing to the progress made in host genetics and HCV molecular virology, emerging data have suggested that the natural course and treatment response in patients with HCV infection are largely determined by complex host‑viral interactions. HCV genotype is the most important viral factor predicting the response to pegylated interferon‑α plus ribavirin therapy. The subtype of HCV genotype 1 is the key viral factor that predicts the efficacy of direct‑acting antiviral therapy. HCV genome heterogeneity and baseline viral load are additionally associated with the treatment response. Multiple host genetic variants localized in genes associated with the immune response have been identified as predictors of spontaneous disease course and therapy outcome in chronic HCV. However, most findings from candidate gene association studies have not been proven universal for all investigated populations and independent studies. Previous findings in independent large genome wide association studies confirmed that interferon‑λ3 gene polymorphisms are associated with spontaneous clearance and treatment responsiveness. A polymorphism of the inosine triphosphatase gene has been identified as a protective factor against ribavirin‑induced anemia and dose reductions. Another genetic variant in the patatin‑like phospholipase domain containing 3 genes is associated with hepatic steatosis and fibrosis in patients with HCV. The present review focused on the identified viral and host factors associated with outcomes of patients with HCV, and assessed the involvement of viral and host genetics in the natural history and treatment outcomes of HCV infection. This will provide novel ideas concerning personalized prevention and individualized clinical management.

Assessment of hepatocellular carcinoma risk based on peg-interferon plus ribavirin treatment experience in this new era of highly effective oral antiviral drugs

In this new era of highly effective oral antiviral drugs for chronic hepatitis C virus (HCV), indications for antiviral treatment may be extendable. This study undertaken to identify suitable candidates for peg-interferon plus ribavirin (PEG-IFN/RBV) treatment by evaluating hepatocellular carcinoma (HCC) risk in patients with chronic HCV treated or not with PEG-IFN/RBV.This large-scale retrospective study was conducted on 1176 patients with chronic HCV without a history of HCC (treatment group [n = 489] and no-treatment group [n = 687]). In the treatment group, patients treated with PEG-IFN/RBV were dichotomized based on the achievement of sustained virologic response (SVR) into SVR (+) and SVR (-) groups.Median follow-up for all study subjects was 31 months (range 6-144 months). Three-year cumulative HCC development rates in the SVR (+) (1.1%) and SVR (-) (8.6%) subgroups were significantly lower than in the no-treatment group (13.5%) (P < 0.01 and P < 0.01, respectively). In all study subjects, presence of cirrhosis (hazard ratio [HR], 9.92, P < 0.01), age (HR 1.03, P < 0.01), SVR (-) (HR 7.02, P < 0.01), and no-treatment (HR 6.76, P < 0.01) were found to be independent risk factors of HCC development. In the treatment group, age, the presence of cirrhosis, and SVR (-) were predictors of HCC development. In the no-treatment group, age, male, and the presence of cirrhosis were independent predictors for HCC development.HCC risk increased in patients with chronic HCV with older age, cirrhosis, SVR (-) after PEG-IFN/RBV treatment, and no PEG-IFN/RBV treatment. Active antiviral therapy based on highly effective oral drugs needs to be considered in these patients.

Management of hepatitis c genotype 4 in the liver transplant setting

End-stage liver disease secondary to hepatitis C virus (HCV) infection is the major indication for orthotopic liver transplantation (OLT) worldwide. The percentage of HCV patients infected with genotype 4 (G4) among recipients of OLT varies depending on geographic location. In the Middle East, including Saudi Arabia, G4 infection is the most common genotype among transplant recipients. Due to the low prevalence of HCV-G4 in Europe and the United States, this genotype has not been adequately studied in prospective trials evaluating treatment outcomes and remains the least studied variant. The aim of this review is to summarize the natural history and treatment outcome of HCV-G4 following liver transplantation, with particular attention to new HCV therapies. This review incorporates all published studies and abstracts including HCV-G4 patients.

Effects of preventive versus "on-demand" nutritional support on paid labour productivity, physical exercise and performance status during PEG-interferon-containing treatment for hepatitis C

BACKGROUND AND OBJECTIVE

Deterioration of nutritional status during PEG-interferon containing therapy for chronic hepatitis C can be ameliorated by preventive nutritional support. We aimed to explore whether such support also affects paid labour productivity, physical exercise and performance status.

METHODS

In this prospective randomized controlled trial (J Hepatol 2012;57:1069-75), 53 patients with chronic hepatitis C had been allocated to "on demand" support (n=26: nutritional intervention if weight loss>5%) or preventive support (n=27: regular dietary advice plus energy- and protein-rich evening snack) during PEG-interferon-containing therapy. Paid labour productivity, physical exercise and performance status were evaluated at baseline, after 24 and (if applicable) after 48 weeks of treatment.

RESULTS

At baseline, 46% of patients performed paid labour and 62% performed some kind of physical exercise. Furthermore, most patients were able to carry out normal activity with only minor symptoms of disease (mean Karnofsky performance score: 94). Decreases of paid labour productivity (-21% vs. -70%, P=0.003), physical exercise activity (-43% vs. -87%, P=0.005) and Karnofsky performance scores (-12% vs. -24%, P<0.001) were less in the preventive than in "on demand" group after 24 weeks of treatment. Effects of preventive nutritional support were even more pronounced after 48 weeks.

CONCLUSIONS

Preventive nutritional support markedly ameliorates decreases of paid labour productivity, physical exercise and performance status during PEG-interferon-containing treatment for chronic hepatitis C.

Secreted Phosphoprotein 1 Promoter Genetic Variants Are Associated with the Response to Pegylated Interferon α Plus Ribavirin Combination Therapy in Egyptian Patients with Chronic Hepatitis C Virus Infection

Background/Aims

The T-helper 1 (TH1) immune reaction is essential for the eradication of hepatitis C virus (HCV) during pegylated interferon α (PEG-IFN-α)- and ribavirin (RBV)-based therapy in chronic HCV patients. Secreted phosphoprotein 1 (SPP1) was shown to be a crucial cytokine for the initiation of a TH1 immune response. We aimed to investigate whether SPP1 single nucleotide polymorphisms (SNPs) may influence sustained virological response (SVR) rates.

Methods

Two SNPs in the promoter region of SPP1 at the −443 C>T and −1748 G>A loci were genotyped in 100 patients with chronic HCV genotype 4 infection using a TaqMan SNP genotyping assay.

Results

Sixty-seven patients achieved a SVR, and 33 patients showed no SVR. Patients carrying the T/T genotype at the −443 locus showed a significantly higher SVR rate than those carrying the C/T or C/C genotype (83.67% vs 50.98%, p<0.001). At the −1748 locus, the SVR rate was significantly higher in patients with the G/G genotype than in those with the A/A genotype (88.89% vs 52.63%, p=0.028) and in patients with the G/A genotype than in those with the A/A genotype (85.29% vs 52.63%, p=0.001).

Conclusions

SPP1 SNPs at −443 C>T and −1748 G>A loci may be useful markers for predicting the response to PEG-IFN-α-2b plus RBV therapy in Egyptian patients with chronic HCV genotype 4 infection.

Cost-effectiveness and budget impact of hepatitis C virus treatment with sofosbuvir and ledipasvir in the United States

BACKGROUND

Sofosbuvir and ledipasvir, which have recently been approved for treatment of chronic hepatitis C virus (HCV) infection, are more efficacious and safer than the old standard of care (oSOC) but are substantially more expensive. Whether and in which patients their improved efficacy justifies their increased cost is unclear.

OBJECTIVE

To evaluate the cost-effectiveness and budget impact of sofosbuvir and ledipasvir.

DESIGN

Microsimulation model of the natural history of HCV infection.

DATA SOURCES

Published literature.

TARGET POPULATION

Treatment-naive and treatment-experienced HCV population defined on the basis of HCV genotype, age, and fibrosis distribution in the United States.

TIME HORIZON

Lifetime.

PERSPECTIVE

Third-party payer.

INTERVENTION

Simulation of sofosbuvir-ledipasvir compared with the oSOC (interferon-based therapies).

OUTCOME MEASURES

Quality-adjusted life-years (QALYs), incremental cost-effectiveness ratios (ICERs), and 5-year spending on antiviral drugs.

RESULTS OF BASE-CASE ANALYSIS

Sofosbuvir-based therapies added 0.56 QALY relative to the oSOC at an ICER of $55 400 per additional QALY. The ICERs ranged from $9700 to $284 300 per QALY depending on the patient's status with respect to treatment history, HCV genotype, and presence of cirrhosis. At a willingness-to-pay threshold of $100 000 per QALY, sofosbuvir-based therapies were cost-effective in 83% of treatment-naive and 81% of treatment-experienced patients. Compared with the oSOC, treating eligible HCV-infected persons in the United States with the new drugs would cost an additional $65 billion in the next 5 years, whereas the resulting cost offsets would be $16 billion.

RESULTS OF SENSITIVITY ANALYSIS

Results were sensitive to drug price, drug efficacy, and quality of life after successful treatment.

LIMITATION

Data on real-world effectiveness of new antivirals are lacking.

CONCLUSION

Treatment of HCV is cost-effective in most patients, but additional resources and value-based patient prioritization are needed to manage patients with HCV.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Current status and emerging challenges in the treatment of hepatitis C virus genotypes 4 to 6

Hepatitis C virus (HCV) genotypes 4, 5 and 6 are mainly present in Africa, the Middle East and Asia and they have been less extensively studied with respect to epidemiology, natural disease history and therapeutic endpoints. Response rates to a 48-wk combined peginterferon/ribavirin treatment range to 40%-69% for HCV 4, 55%-60% for HCV 5 and 60%-90% for HCV 6. Response-guided schedules are recommended to optimize the outcomes of peginterferon/ribavirin treatment in HCV 4 and, in form of preliminary data, for HCV 6, but no data are yet available to support such an individualization of therapy for HCV 5. Recently, the direct-acting antivirals (DAAs) with pan-genotypic activities simeprevir, sofosbuvir and daclatasvir have been recommended in triple regimens with peginterferon/ribavirin for the treatment of HCV genotypes 4 to 6 infections. In the future, DAA-based interferon-free therapies are awaited to drastically improve treatment outcomes in HCV. However, efforts to improve treatment outcomes with peginterferon/ribavirin should continue, as the HCV 4-6 infected population is mainly based in resource-limited settings with restricted access to the costly DAAs.

Protein kinase expression as a predictive factor for interferon response in chronic hepatitis C patients

Egypt has the highest prevalence of hepatitis C virus (HCV) worldwide. Currently, combined pegylated interferon and ribavirin therapy are the standard treatment. The biological activity of interferon (IFN) is mediated by the induction of intracellular antiviral proteins, such as 2'-5' oligoadenylate synthetase, and dsRNA-activated protein kinase. IFN-inducible double-stranded RNA-activated protein kinase (PKR) is thought to play a key antiviral role against HCV. Some studies observed that PKR expression was higher in sustained viral responders compared with the non-responders. The PKR is considered as antiviral toward HCV and responsible for IFN's effect against HCV while others have showed that, there were kinetic results indicate that HCV infection is not altered by reduced levels of PKR, indicating that HCV is resistant to the translational inhibitory effects of the phosphorylated forms of PKR. This study was conducted on 50 consecutive patients with chronic HCV infection (CHC) and 20 healthy controls. All the patients were subjected to clinical and laboratory assessment, abdominal ultrasound, and liver biopsy. Determination of PKR gene quantity by using a real time PCR was done at the baseline and at the end of treatment for all patients and controls. Pre-treatment levels of protein kinase gene were significantly higher in responders in comparison with non-responders (P < 0.001). It was found that 97.06% of patients who were responding to treatment had the expression of protein kinase gene greater than 2(6) cycle threshold.

Viral hepatitis C therapy: pharmacokinetic and pharmacodynamic considerations

Chronic hepatitis C is a global health problem. To prevent or reduce complications, the hepatitis C virus (HCV) infection needs to be eradicated. There have been several developments in treating these patients since the discovery of the virus. As of 1 January 2014, the drugs that are approved for treatment of chronic HCV infection are peginterferon-α, ribavirin, boceprevir, telaprevir, simeprevir and sofosbuvir. In this review we provide an overview of the clinical pharmacokinetic characteristics of these agents by describing their absorption, distribution, metabolism and excretion. In the pharmacodynamic part we summarize what is known about the relationships between the pharmacokinetics of each drug and efficacy or toxicity. We briefly discuss the pharmacokinetics and pharmacodynamics of chronic hepatitis C treatment in special patient populations, such as patients with liver cirrhosis, renal insufficiency or HCV/HIV coinfection, and children. With this knowledge, physicians, pharmacists, nurse practitioners, etc. should be educated to safely and effectively treat HCV-infected patients.

Meta-analysis: influence of host and viral factors in patients with chronic hepatitis C genotype 4 treated with pegylated interferon and ribavirin

The burden of hepatitis C virus genotype 4 (HCV-4) is high in Africa and East Mediterranean countries. Previous reports estimate sustained virologic response (SVR) rates in HCV-4 to be ∼20-70%. However, many of these studies are limited by different study designs and small sample sizes. Our aim was to evaluate treatment outcome and host/viral factors on SVR in HCV-4 patients treated with pegylated interferon and ribavirin (PEG IFN+RBV) in a systematic and quantitative manner. A comprehensive literature search in MEDLINE and EMBASE for 'genotype 4' was conducted in November 2013. Abstracts from American Association for the Study of Liver Diseases, Asian Pacific Study of the Liver, Digestive Disease Week, and European Association for the Study of the Liver in 2012/2013 were reviewed. Inclusion criteria were original studies with at least 25 treatment-naive HCV-4 patients treated with PEG IFN+RBV. Exclusion criteria were coinfection with HIV, hepatitis B virus, or other genotypes. Effect sizes were calculated using random-effects models. Heterogeneity was determined by Cochrane Q-test (P<0.05) and I statistic (>50%). We included 51 studies (11 102 HCV-4 patients) in the primary analysis. Pooled SVR was 53% [95% confidence interval (CI): 50-55%] (Q-statistic=269.20, P<0.05; I=81.43). On subgroup analyses, SVR was significantly associated with lower viral load, odds ratio (OR) 3.05 (CI: 1.80-5.17, P<0.001); mild fibrosis, OR 3.17 (CI: 2.19-4.59, P<0.001); and favorable IL28B polymorphisms, rs12979860 CC versus CT/TT, OR 4.70 (CI: 2.87-7.69, P<0.001), and rs8099917 TT versus GT/GG, OR 5.21 (CI: 2.31-11.73, P<0.001). HCV-4 patients treated with PEG IFN+RBV may expect SVR rates of ∼50%. Lower viral load, mild fibrosis, and favorable IL28B (rs12979860 CC and rs8099917 TT) are positively associated with SVR.

Pegylated interferon alfa-2b plus ribavirin for treatment of chronic hepatitis C

AIM: To study the safety and efficacy of pegylated interferon alfa-2b, indigenously developed in India, plus ribavirin in treatment of hepatitis C virus (HCV).

METHODS: One-hundred HCV patients were enrolled in an open-label, multicenter trial. Patients were treated with pegylated interferon alfa-2b 1.5 μg/kg per week subcutaneously plus oral ribavirin 800 mg/d for patients with genotypes 2 and 3 for 24 wk. The same dose of peginterferon plus weight-based ribavirin (800 mg/d for ≤ 65 kg; 1000 mg/d for > 65-85 kg; 1200 mg/d for > 85-105 kg; 1400 mg/d for > 105 kg body weight) was administered for 48 wk for patients with genotypes 1 and 4. Serological and biochemical responses of patients were assessed.

RESULTS: Eighty-two patients (35 in genotypes 1 and 4 and 47 in 2 and 3), completed the study. In genotype 1, 25.9% of patients achieved rapid virologic response (RVR): while the figures were 74.1% for early virologic response (EVR) and 44.4% for sustained virologic response (SVR). For genotypes 2 and 3, all patients bar one belonged to genotype 3, and of those, 71.4%, 87.5%, and 64.3% achieved RVR, EVR, and SVR, respectively. In genotype 4, 58.8%, 88.2%, and 52.9% of patients achieved RVR, EVR, and SVR, respectively. The majority of patients attained normal levels of alanine aminotransferase by 4-12 wk of therapy. Most patients showed a good tolerance for the treatment, although mild-to-moderate adverse events were exhibited; only two patients discontinued the study medication due to serious adverse events (SAEs). Eleven SAEs were observed in nine patients; however, only four SAEs were related to study medication.

CONCLUSION: Peginterferon alfa-2b, which was developed in India, in combination with ribavirin, is a safe and effective drug in the treatment of HCV.

The efficacy of a Hansenula-derived 20 kDa pegylated interferon alpha-2a in the treatment of genotype 4 chronic hepatitis C

Pending the emergence and approval of an effective interferon-free regimen, pegylated interferon will remain an integral part of the treatment of genotype 4 hepatitis C virus (HCV). A new 20 kDa pegylated interferon has been developed in a cost-saving fungal-based system and is commercialized in Egypt at a quarter to a third of the price of conventional pegylated interferon. We hereby test the efficacy and safety of this novel cost-saving interferon. One hundred ninety-three consecutive treatment-naive patients with genotype 4 HCV were treated using the following regimen: subcutaneous 20 kDa pegylated interferon 160 μg once weekly plus oral ribavirin 1,000 or 1,200 mg daily (based on body weight <75 kg or ≥75 kg, respectively) for 48 weeks. A sustained virological response (SVR) of 51% was achieved. Interim responses included rapid virological response (RVR): 54%, early virological response (EVR): 78% (complete EVR: 71%, partial EVR: 7%), and end of treatment response: 63%. The most common adverse events were flu-like symptoms, dyspepsia, anorexia, and pruritus. Treatment-related serious adverse events were encountered in only 2 patients (1%). Discontinuation of treatment due to adverse events occurred in only 13 patients (7%). Multiple logistic regression analyses revealed the following factors as predictors of SVR: RVR (P<0.001), alpha-fetoprotein<upper limit of normal (ULN) (P=0.007), and early biochemical response (alanine aminotransferase <ULN at week 12, P=0.018). Hansenula-derived 20 kDa pegylated interferon alpha-2a is an effective and safe treatment for genotype 4 chronic HCV. These results highlight the presence of a less costly treatment for chronic HCV, pending the emergence of an effective inexpensive interferon-free regimen. A direct comparison with 40 kDa interferon remains essential to adequately compare the efficacy and safety.

Optimizing outcome of recurrent hepatitis C virus genotype 4 after living donor liver transplantation: moving forward by looking back

PURPOSE

Recurrence of HCV after LDLT is almost universal. Different factors affect response to treatment. Few data are available regarding outcome of recurrent HCV genotype 4. The purpose of this study is to improve outcome of recurrent HCV genotype 4 after LDLT.

METHODS

An IRB approved chart review of 243 patients transplanted for ESLD, HCV genotype 4 over 4 years were reviewed. Protocol liver biopsies were taken 6 months after transplant. Patients received pegylated interferon and ribavirin in case of histological recurrence. Five patients had FCH were excluded.

RESULTS

Thirty-seven patients were included. Sustained Virological Response (SVR) was achieved in 29 (78.3%). Patients with Metavir fibrosis stage (F0) and (F1) had SVR in 5/5 (100%) and 20/24 (83.3%). Two patients with F1 had to stop treatment because of thrombocytopenia and 2 were non responders. Three out of 6 patients (50%) with (F2) had SVR, 2 were non responders and one had to discontinue treatment because of severe depression. One of 2 patients (50%) with F3 had SVR and the other patient decompensated within 4 months before treatment and died.

CONCLUSION

Protocol biopsies allow early detection of inflammatory changes in the graft before fibrosis occurs. Early treatment of recurrent HCV genotype 4 after LDLT results in better response.

Peginterferon plus ribavirin versus interferon plus ribavirin for chronic hepatitis C

BACKGROUND

Pegylated interferon (peginterferon) plus ribavirin is the recommended treatment for patients with chronic hepatitis C, but systematic assessment of the effect of this treatment compared with interferon plus ribavirin is needed.

OBJECTIVES

To systematically evaluate the benefits and harms of peginterferon plus ribavirin versus interferon plus ribavirin for patients with chronic hepatitis C.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Science Citation Index-Expanded, and LILACS. We also searched conference abstracts, journals, and grey literature. The last searches were conducted in September 2013.

SELECTION CRITERIA

We included randomised clinical trials comparing peginterferon plus ribavirin versus interferon plus ribavirin with or without co-intervention(s) (e.g., other antiviral drugs) for chronic hepatitis C. Quasi-randomised and observational studies retrieved through the searches for randomised clinical trials were also considered for reports of harms. Our primary outcomes were liver-related morbidity, all-cause mortality, serious adverse events, adverse events leading to treatment discontinuation, other adverse events, and quality of life. Our secondary outcome was sustained virological response in serum, that is, undetectable hepatitis C virus RNA in serum by sensitive tests six months after the end of treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently used a standardised data collection form. We meta-analysed data with both fixed-effect and random-effects models. For each outcome, we calculated the odds ratio (OR) (for liver-related morbidity or all-cause mortality) or the risk ratio (RR) along with 95% confidence interval (CI) based on intention-to-treat analysis. We used domains of the trials to assess the risk of systematic errors (bias) and trial sequential analyses to assess the risk of random errors (play of chance).For each outcome, we calculated the RR with 95% CI based on intention-to-treat analysis. Effects of interventions on outcomes were assessed according to GRADE.

MAIN RESULTS

We included 27 randomised trials with 5938 participants. All trials had high risk of bias. We considered that the risk of bias did not impact on the quality of evidence for liver-related mortality and adverse event outcomes, but it did for virological response. All trials compared peginterferon alpha-2a or peginterferon alpha-2b plus ribavirin versus interferon plus ribavirin for participants with chronic hepatitis C. Three trials administered co-interventions (amantadine hydrochloride 200 mg daily to both intervention groups), and 24 trials were conducted without co-interventions. The effect observed between the two intervention groups regarding liver-related morbidity plus all-cause mortality (5/907 (0.55%) versus 4/882 (0.45%) was imprecise: OR 1.14 ( 95% CI 0.38 to 3.42; five trials; low quality of evidence), as was the risk of adverse events leading to treatment discontinuation (332/2692 (12.3%) versus 409/2176 (18.8%); RR 0.86, 95% CI 0.68 to 1.09; 15 trials; low quality of evidence) or regarding adverse events leading to treatment discontinuation (332/2692 (12.3%) versus 409/2176 (18.8%); RR 0.86, 95% CI 0.66 to 1.12; 17 trials; low quality of evidence). However, peginterferon plus ribavirin versus interferon plus ribavirin significantly increased the risk of neutropenia (332/2202 (15.1%) versus 117/1653 (7.1%); RR 2.15, 95% CI 1.76 to 2.61; 13 trials), thrombocytopenia (65/1113 (5.8%) versus 23/1082 (2.1%); RR 2.63, 95% CI 1.68 to 4.11; 10 trials), arthralgia (517/1740 (29.7%) versus 282/1194 (23.6%); RR 1.19, 95% CI 1.05 to 1.35; four trials), injection site reaction (627/1168 (53.7%) versus 186/649 (28.7%); RR 1.71, 95% CI 1.50 to 1.93; four trials), and nausea (606/1784 (34.0%) versus 354/1239 (28.6%); RR 1.13, 95% CI 1.01 to 1.26; four trials). The most frequent adverse event was fatigue, which occurred in 57% of participants (2024/3608). No significant difference was noted between peginterferon plus ribavirin versus interferon plus ribavirin in terms of fatigue (1177/2062 (57.1%) versus 847/1546 (54.8%); RR 1.01, 95% CI 0.96 to 1.07; 12 trials). No significant differences were reported between the two treatment groups regarding anaemia, headache, rigours, myalgia, pyrexia, weight loss, asthenia, depression, insomnia, irritability, alopecia, pruritus, skin rash, thyroid malfunction, decreased appetite, or diarrhoea. We were unable to identify any data on quality of life. Peginterferon plus ribavirin versus interferon plus ribavirin seemed to significantly increase the number of participants achieving sustained virological response (1673/3300 participants (50.7%) versus 1081/2804 patients (36.7%); RR 1.39, 95% CI 1.25 to 1.56; I2 = 64%; 27 trials; very low quality of evidence). However, the risk of bias in the 13/27 (48.1%) trials reporting on this outcome was high and was considered only 'lower' in the remainder. Because the conventional meta-analysis did not reach its required information size (n = 14,486 participants), we used trial sequential analysis to control for risks of random errors. Again, in this analysis, the estimated effect was statistically significant in favour of peginterferon. Subgroup analyses according to risk of bias, viral genotype, baseline viral load, past treatment history, and type of intervention yielded similarly significant results favouring peginterferon over interferon on the outcome of sustained virological response.

AUTHORS' CONCLUSIONS

Peginterferon plus ribavirin versus interferon plus ribavirin seems to significantly increase the proportion of patients with sustained virological response, as well as the risk of certain adverse events. However, we have insufficient evidence to recommend or reject peginterferon plus ribavirin for liver-related morbidity plus all-cause mortality compared with interferon plus ribavirin. The clinical consequences of achieved sustained virological response are unknown, as sustained virological response is still an unvalidated surrogate outcome. We found no evidence of the potential benefits on quality of life in patients with achieved sustained virological response. Further high-quality research is likely to have an important impact on our confidence in the estimate of patient-relevant outcomes and is likely to change our estimates.There is very low quality evidence that peginterferon plus ribavirin increases the proportion of patients with sustained virological response in comparison with interferon plus ribavirin. There is evidence that it also increases the risk of certain adverse events.

Measuring ribavirin concentrations during the earliest stages of antiviral therapy for hepatitis C: potential relevance for treatment outcome

BACKGROUND

Correlations between ribavirin (RBV) concentrations and sustained virological response (SVR) to hepatitis C virus treatment have been demonstrated previously. As steady state is reached after several weeks of RBV treatment, dose modifications based on steady-state levels can only be applied relatively late in treatment, possibly too late to influence SVR rates. The authors aimed to determine whether measurement of early concentrations is useful to predict optimal steady-state RBV concentrations.

METHODS

In 61 treatment-naive genotype 1/4 patients RBV concentrations were determined in samples collected after 1, 2, 4, 8, 12, and 24 weeks of therapy. RBV concentrations were compared between responders and nonresponders; Receiver Operating Characteristic analyses were conducted to find optimal cut-off values to predict week 8 concentrations from earlier measurements.

RESULTS

Median week 8 RBV concentrations were significantly higher in patients with SVR compared with those without: 3.4 (interquartile range 2.4-3.9) versus 2.6 (interquartile range 2.0-3.5) mg/L (P < 0.05). RBV concentration at week 8 was an independent predictor of SVR [adjusted odds ratio 2.3 (95% confidence interval: 1.1-4.9; P = 0.03)]. The optimal cut-off value of week 8 RBV concentration to predict SVR was 2.20 mg/L [sensitivity 87%, specificity 40%, positive predictive value 64%, negative predictive value 71%]. Optimal cut-off values at weeks 1, 2, or 4 to predict an RBV concentration ≥2.20 mg/L at week 8 were 0.92, 1.29, and 1.67 mg/L, respectively, with positive predictive values and negative predictive values ranging from 88% to 91% and 71% to 86%, respectively.

CONCLUSIONS

RBV concentrations in the earliest stages of antiviral therapy predict therapeutic steady-state concentrations, allowing timely dose adjustments with potential implications for treatment outcome.

Prevention of hepatitis C virus infection and liver cancer

Hepatocellular carcinoma (HCC) is the fifth most prevalent cancer and the third leading cause of cancer-related death, and its incidence is increasing. The majority of HCC cases are associated with chronic viral hepatitis. With over 170 million individuals chronically infected with hepatitis C virus (HCV) worldwide, HCV is currently a serious global health concern, leading to chronic hepatitis, cirrhosis and HCC, thereby causing significant morbidity and mortality. With the incidence of HCV infection increasing, the problem of HCV-associated HCC is expected to worsen as well, with the majority of HCCs developing in the setting of cirrhosis. Thus, it is imperative to provide antiviral therapy to infected individuals prior to the development of established cirrhosis in order to reduce the risk of subsequent HCC. Indeed, the successful eradication of HCV is associated with clinical and histological improvement as well as a greatly reduced risk of subsequent HCC development. Even after the development of cirrhosis, successful viral clearance is still associated with reduced HCC risk. Current standard of care antiviral treatment consists of pegylated interferon-α and ribavirin, but viral clearance rates are suboptimal with this regimen, especially in difficult to treat cohorts. However, there is a myriad of different classes of HCV-specific direct-acting antiviral agents currently in development, which can be used in combination with one another or with standard of care treatment to improve HCV cure rates. Preventative and therapeutic vaccines against HCV remain an area of ongoing research with good progress towards developing an effective vaccine in the future.

Pegylated versus standard interferon plus ribavirin in chronic hepatitis C genotype 4: A systematic review and meta-analysis

AIM

Treatment of hepatitis C genotype 4 (HCV-G4) with pegylated interferon (PEG IFN) has not been adequately studied and is considered to be challenging. The aim of this meta-analysis is to systematically review and evaluate the effectiveness of 48 weeks of combined PEG IFN plus ribavirin (RBV) compared to standard interferon (IFN) plus RBV. The outcome of interest is sustained virological response (SVR).

METHODS

We searched for eligible randomized controlled trials (RCT) through May 2012. Random effects meta-analysis was used to pool the risk ratio (RR) of achieving SVR across trials.

RESULTS

Five RCT enrolling 386 patients were included. The PEG IFN/RBV group had increased likelihood of achieving SVR (RR = 1.51, 95% confidence interval [CI] = 1.08-2.10). SVR was significantly higher in PEG IFN-α-2a compared to the -α-2b group (P = 0.02). There was no statistically significant effect of ribavirin dosage on SVR (P = 0.55). The quality of evidence was moderate overall and limited by heterogeneity.

CONCLUSION

In treatment-naive patients with HCV-G4, treatment with PEG IFN plus RBV achieves higher SVR rate than treatment with IFN plus RBV.

Peginterferon plus Chinese herbal therapy is associated with a higher virological response than only peginterferon therapy in chronic hepatitis C

Traditional Chinese herbal therapies are widely used for the treatment of chronic hepatitis C (CHC) in China and several Asian countries. The aim of this study was to perform a meta-analysis of randomized controlled trials (RCTs) comparing peginterferon therapy with peginterferon plus Chinese herbal therapy for the treatment of CHC. The Cochrane Central Register of Controlled Trials, Medline, Science Citation Index, EMBASE, China National Knowledge Infrastructure, Wanfang Database, and China Biomedical Database were searched to identify RCTs that evaluated the virological response of CHC patients to peginterferon therapy and peginterferon plus Chinese herbal therapy. We statistically combined data using a fixed-effects meta-analysis according to the intention-to-treat principle. The literature search yielded 905 studies and nine RCTs composed of 858 patients matched the selection criteria. Overall, sustained virological response (SVR) was significantly higher in patients treated with peginterferon plus Chinese herbs than in patients treated with peginterferon alone (81 % vs. 64 %, respectively; odds ratio, 2.60; 95 % confidence interval: 1.32–5.14; p < 0.05). A combined therapy of peginterferon plus Chinese herbs was also superior to peginterferon therapy in achieving an early viral response (EVR, 80 % vs. 70 %, respectively), a viral response at week 24 of treatment (82 % vs. 73 %, respectively), and end-of-treatment viral response (ETVR, 73 % vs. 62 %, respectively). The combined therapy resulted in fewer relapses, fewer adverse events, and more rapid alanine transaminase normalization; however, both treatments yielded a similar rapid viral response (RVR, 53 % vs. 57 %, respectively). The current evidence suggests that combined therapy of peginterferon plus Chinese herbs yields a higher viral response and results in fewer relapses and fewer adverse events than peginterferon therapy alone.

Relationship of interferon-γ-inducible protein-10 kDa with viral response in patients with various heterogeneities of hepatitis C virus genotype-4

INTRODUCTION

The role of serum interferon-γ-inducible protein-10 kDa (IP-10) level in the treatment of chronic hepatitis C genotype-4 (HCV-4) and its various subtypes remains unknown. We aimed to study the impact of pretreatment IP-10 levels on the sustained viral response (SVR) in HCV-4 patients (n=64) undergoing peginterferon α-2a/ribavirin therapy.

PATIENTS AND METHODS

Pretreatment IP-10 levels and HCV-4 subtypes (4a=48.4%, 4d=39%, others=12.5%) were measured and correlated with treatment responses. Variables significantly associated with SVR on univariate analysis were included in a multivariate logistic regression model.

RESULTS

Patients with SVR had lower pretreatment IP-10 levels (462.4±282.7 vs. 840.1±490.6 pg/ml; P=0.002), but the levels were not significantly different in those with a rapid (P=0.245) or an early viral response (P=0.221). IP-10 levels were similar across all subtypes. The pretreatment level was significantly lower in subtype 4d patients with SVR (465.9±349.1) compared with non-SVR patients (904.9±532.1; P<0.001), but not when compared with genotype 4a patients (564.7±288.9 vs. 658.6±374.9, respectively; P=0.330). IP-10 levels [odds ratio (OR), 0.998; 95% confidence interval (CI): 0.996-0.999; P=0.006], low viremia (OR, 8.852; 95% CI: 1.244-63.03; P=0.029), and early viral response (OR, 4.162; 95% CI: 1.023-16.94; P=0.046) were independent predictors of SVR. Receiver operating characteristic curve analysis identified a threshold IP-10 level of 359 pg/ml (area under receiver operating characteristic curve, 0.737; sensitivity, 81.8%; specificity, 45.2; positive predictive value, 43.9%; negative predictive value, 82.6%) for SVR.

CONCLUSION

Pretreatment serum IP-10 level is a predictor for SVR in HCV-4-infected patients. The baseline IP-10 level is significantly lower in responders among HCV genotype-4d patients as compared with 4a patients.

Natural killer cell activity and function in chronic HCV-infected patients during peg interferon and ribavirin: early effects of active substance use

In Western countries, chronic hepatitis C virus (HCV)-infection mostly affects former and active substance users. The effect of active substance use on interferon (IFN)-responsiveness and therapy efficacy is not well understood. In this study, we compared natural killer (NK) cell activity and function in healthy controls and chronic HCV-infected patients with and without active substance use, as well as the early effects of antiviral therapy with peg-IFN and ribavirin. No differences were observed between chronic HCV patients and healthy individuals in the number and frequencies of CD56(dim) and CD56(bright) NK cells. Also, IL-12/18-induced IFN-gamma production by NK cells was comparable between all groups, whereas the cytotoxic ability of NK cells (granzyme and CD107a levels) was more potent in HCV-infected patients as compared to healthy controls, and highest in non-substance users. Moreover, at baseline, the activation of NK cells was significantly lower in HCV-infected patients who used substances, when compared to healthy individuals. Therapy-induced viral load reduction assessed early at day 7 showed a similar decline in substance users and non-substance use HCV patients, with 25% substance users and 17% non-substance users testing HCV-RNA negative at day 7. Furthermore, early during IFN-based therapy, NK cells from HCV patients remained responsive to IFN, and only a minor decline in the degree of STAT-1 phosphorylation was observed irrespective of substance use. These findings were further supported by comparable in vitro p-STAT-1 induction in all three experimental groups. Despite subtle differences at baseline between healthy individuals and chronic HCV patients, we observed that active substance use in chronic HCV-infected patients did not affect the immune responsiveness to IFN early after start of treatment, and thus, we found no evidence - from an immunological point of view - that antiviral therapy of our cohort of HCV-infected patients with active substance use is less efficient.

Predictors of sustained virological response in Greek and Egyptian patients with hepatitis C genotype 4: does ethnicity matter?

Hepatitis C virus genotype 4 (HCV-4) is spreading beyond Africa and the Middle East but data regarding treatment with pegylated interferon alpha and ribavirin of European populations infected with HCV-4 remains limited. Interestingly, European (vs. Egyptian) origin has been associated with lower sustained virological response rates. Hence the aim of this study was to investigate the treatment outcomes of Greek (vs. Egyptian), treatment-naïve patients infected with HCV-4 (subtype a) and to identify factors influencing response rates. One hundred seventy-seven consecutive patients (mean age: 44.6 ± 10.2, males: 143/177; 80.8%, Egyptians: 76/177; 42.9%) treated over a 7-year period at the Hepatology clinics of three tertiary care hospitals in Greece were retrospectively evaluated. Overall, sustained virological response was achieved in 75/177 (42.4%) of the cohort without a significant difference between the two ethnic groups [Greek: 44/101 (43.6%); Egyptian 31/76 (40.8%), P = 0.7598]. In multivariate analysis, it was found that ethnicity was not associated with an impaired response but age ≥45 years [odds ratio (OR): 0.4225, 95% confidence interval (CI): 0.2135-0.8133; P = 0.0134], diabetes (OR: 0.2346, 95% CI: 0.0816-0.0674; P = 0.0071), advanced liver fibrosis (OR: 0.3964, 95% CI: 0.1933-0.8133; P = 0.0116), and treatment suspension (OR: 0.1738, 95% CI: 0.0482-0.6262; P = 0.0075) showed an independent negative association with response to antiviral treatment. In contrast to previous European data suggesting Egyptian ethnicity to be a positive predictor for a sustained virological response, there was no influence of Greek versus Egyptian ethnicity on treatment outcomes. Higher age, advanced liver fibrosis, and diabetes have been shown to reduce significantly response rates in patients infected with HCV-4.

Extended peginterferon plus ribavirin treatment for 72 weeks versus standard peginterferon plus ribavirin treatment for 48 weeks in chronic hepatitis C genotype 1 infected slow-responder adult patients

BACKGROUND

The standard length of peginterferon plus ribavirin treatment for chronic hepatitis C virus (HCV) genotype 1 infected patients is 48 weeks. However, the number of patients demonstrating a sustained virological response is not high. In order to improve sustained virological response, extending the length of the treatment period has been suggested.

OBJECTIVES

To study the benefits and harms of extended 72-week treatment in comparison with 48-week treatment with peginterferon plus ribavirin in patients with chronic HCV genotype 1 infection who have shown a slow antiviral response.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and LILACS until November 2011. We identified further trials by reviewing reference lists and contacting principal authors.

SELECTION CRITERIA

Trials were eligible for this review if they included patients infected with hepatitis C virus genotype 1 who had a slow antiviral response, and if those patients were randomised to completing 72 weeks versus 48 weeks of treatment with pegylated interferon and ribavirin.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the trials for risk of bias, and extracted the data. The primary outcomes were overall mortality, liver-related mortality, and liver-related morbidity. We extracted data separately according to two definitions of slow responders: 1) patients with ≥ 2 log viral reduction but still detectable HCV RNA after 12 weeks of treatment and undetectable HCV RNA after 24 weeks of treatment; 2) patients with detectable HCV RNA after four weeks of treatment. We calculated risk ratios from individual trials as well as in the meta-analyses of trials.

MAIN RESULTS

We included seven trials with 1369 participants. All trials had high risk of bias. Five trials used our first definition of slow responders, and three other trials (including one that used both definitions) used the second definition. None of the included trials mentioned our primary outcomes. However, regarding the secondary outcomes, extension of the treatment period to 72 weeks increased the sustained virological response according to both definitions (71/217 (32.7%) versus 52/194 (26.8%); risk ratio (RR) 1.43, 95% confidence interval (CI) 1.07 to 1.92, P = 0.02, I(2) = 8%; and 265/499 (53.1%) versus 207/496 (41.7%); RR 1.27, 95% CI 1.07 to 1.50, P = 0.006, I(2) = 38%), with a risk difference of 0.11 and calculated number needed to treat of nine. The end of treatment response was not significantly different between the two treatment groups. The number of participants who relapsed virologically was found to be lower in the groups that had been treated for 72 weeks using both definitions (27/84 (32.1%) versus 46/91 (50.5%); RR 0.59, 95% CI 0.40 to 0.86, P = 0.007, I(2) = 18%, 3 trials; and 85/350 (24.3%) versus 146/353 (41.4%); RR 0.59, 95% CI 0.47, 0.73, P < 0.000001, I(2) = 0%, 3 trials). The length of treatment did not significantly affect the adherence (247/279 (88.5%) versus 252/274 (92.0%); RR 0.95, 95% CI 0.84 to 1.07, P = 0.42, I(2) = 69%, 3 trials). In the single trial that reported adverse events, no significant difference was seen between the two treatment groups.

AUTHORS' CONCLUSIONS

This review demonstrates higher a proportion of sustained virological response after extension of treatment from 48 weeks to 72 weeks in HCV genotype 1 infected patients in whom HCV RNA was still detectable but decreased by ≥ 2 log after 12 weeks and became negative after 24 weeks of treatment, and in patients with detectable HCV RNA after four weeks of treatment with peginterferon plus ribavirin. The observed intervention effects can be caused by both systematic error (bias) and random errors (play of chance). There was no reporting on mortality and the reporting of clinical outcomes and adverse events was insufficient. More data are needed in order to recommend or reject the policy of extending the treatment period for slow responders.

Telaprevir: a hepatitis C NS3/4A protease inhibitor

BACKGROUND

Telaprevir is a hepatitis C NS3/4A protease inhibitor approved by the US Food and Drug Administration as part of combination therapy for the management of chronic hepatitis C virus (HCV) genotype 1 infection.

OBJECTIVE

The article reviews published literature on telaprevir, including its chemistry, mechanism of action, resistance, pharmacodynamic and pharmacokinetic properties, drug interactions, therapeutic efficacy, HIV/HCV coinfection, pharmacogenomics, adverse events, pharmacoeconomics, and dosing and administration.

METHODS

English-language literature was included. Searches of MEDLINE and BIOSIS databases from 1975 through January 2012 were performed. Emphasis was placed on reference citations involving clinical trials, randomized controlled trials, and research in humans. Additional publications were found by searching the reference lists of identified articles and reviewing abstracts from recent scientific meetings. Search terms included, but were not limited to, telaprevir, VX-950, hepatitis C virus genotype 1, resistance, pharmacology, pharmacokinetics, pharmacodynamics, drug interactions, pharmacogenomics, adverse events, and therapeutic use.

RESULTS

Review of the databases revealed 471 publications/abstracts on this subject. Of these, 85 were chosen based on the review criteria. Two Phase III studies investigated the efficacy and tolerability of telaprevir administered for 12 weeks (T12) when used with peginterferon alfa and ribavirin (PR) in treatment-naive subjects. The ADVANCE study reported that patients who had an extended rapid virologic response (eRVR; an undetectable HCV RNA level at both 4 and 12 weeks of treatment) with triple therapy could be treated with PR for a total of 24 weeks (T12PR24 group) versus standard PR treatment for 48 weeks (PR48 group [control]). The proportions of patients who achieved sustained virologic response (SVR; undetectable HCV RNA concentration at 24 weeks after the completion of therapy) in the T12PR24 and PR48 groups were 89% and 44%, respectively. The ILLUMINATE study reported T12PR24 was noninferior to T12PR48 in patients with an eRVR to combination therapy. In the REALIZE study, patients with a history of relapse responded well to T12PR48 compared with PR48 (SVR, 83% vs 24%). Telaprevir is a substrate/inhibitor of cytochrome P450 (CYP3A4) and a substrate/inhibitor of P-glycoprotein and poses an important risk for drug interactions. Adverse drug events (ADEs) reported most commonly with triple therapy compared with the T or PR regimen alone were rash, pruritus, nausea, diarrhea, and anemia. The serious AEs most commonly reported during T + PR therapy were anemia, rash, and pruritus. Two reports concluded that T combined with PR was not cost-effective due to the high cost of telaprevir. One study reported that the combination of T + PR would be cost-effective if the treatment rate of HCV genotype 1 infected patients reached 50%.

CONCLUSION

Including telaprevir as part of triple therapy for the management of chronic HCV genotype 1 infection significantly increases the likelihood of achieving an SVR over standard dual drug therapy (PR) in both treatment-naive and -experienced patients. However, due to the high cost, the use of triple therapy with telaprevir will likely be limited to patient groups known to respond poorly to dual therapy.

Antiviral activity of TMC435 monotherapy in patients infected with HCV genotypes 2-6: TMC435-C202, a phase IIa, open-label study

BACKGROUND & AIMS

TMC435 is an investigational, once-daily, oral NS3/4A protease inhibitor currently in phase III development for the treatment of hepatitis C virus (HCV) infection. Phase I and II studies in patients infected with HCV genotype 1 have demonstrated that TMC435 is generally well tolerated, has a pharmacokinetic profile that supports once daily dosing, and demonstrates potent antiviral activity. This phase IIa study (TMC435-C202; NCT00812331) was conducted to investigate the antiviral activity, safety, tolerability, and pharmacokinetics of TMC435 in treatment-naїve patients infected with HCV genotypes 2-6.

METHODS

The study consisted of 7 days of monotherapy with TMC435 (200mg once daily). Patients could begin treatment with pegylated interferon/ribavirin from day 8 with a follow-up period up to days 37-42.

RESULTS

Thirty-seven patients were enrolled in Germany, Belgium and Thailand. For the primary end point at day 8, the mean (± standard error) change in plasma HCV ribonucleic acid (log(10)IU/ml) from baseline was the greatest for genotypes 6 (-4.35 ± 0.29) and 4 (-3.52 ± 0.43), followed by genotypes 2 (-2.73 ± 0.71) and 5 (-2.19 ± 0.39). No antiviral activity was evident for genotype 3. Viral breakthrough occurred in six patients during the monotherapy phase and in six additional patients during PegIFN/RBV-only period. All adverse events were mild or moderate and there were no discontinuations during the TMC435 monotherapy period.

CONCLUSIONS

The results of this phase IIa proof-of-concept trial provide evidence that TMC435 has a spectrum of activity against multiple HCV genotypes, except for genotype 3. In this study, TMC435 was generally safe and well tolerated.

Pharmacokinetics and antiviral activity of PHX1766, a novel HCV protease inhibitor, using an accelerated Phase I study design

BACKGROUND

PHX1766 is a novel HCV NS3/4 protease inhibitor with robust potency and high selectivity in replicon studies (50% maximal effective concentration 8 nM). Two clinical trials investigated the safety, tolerability, pharmacokinetics and antiviral activity of PHX1766 in healthy volunteers (HV) and chronic hepatitis C patients, by use of a dose-adaptive overlapping clinical trial design.

METHODS

Two randomized, double-blind, placebo-controlled clinical trials were conducted. Single doses of PHX1766 or placebo were administered to 25 HV and six HCV genotype 1-infected patients (50 mg once daily -1,000 mg once daily, 250 mg twice daily and 100 mg of a new formulation of PHX1766 once daily). Multiple doses of PHX1766 or placebo were administered to 32 HV and seven HCV genotype 1-infected patients (50 mg once daily -800 mg twice daily).

RESULTS

Oral administration of PHX1766 was safe and well tolerated at all dose levels with rapid absorption (time at which concentration maximum is reached of 1-4 h) and with mean terminal half-lives of 4-23 h. Multiple doses of PHX1766 800 mg twice daily in HCV patients produced an area under the plasma concentration-time curve from time of drug administration to the last time point with a measurable concentration after dosing accumulation ratio of 2.3. The mean maximal observed HCV RNA decline was 0.6 log(10) IU/ml in the first 24 h in the single-dose protocol and 1.5 log(10) IU/ml after 6 days of PHX1766 dosing.

CONCLUSIONS

An overlapping, dose-adaptive single-dose and multiple-dose escalating design in HV and HCV-infected patients proved to be highly efficient in identifying a therapeutic dose. Although in vitro replicon studies indicated a robust HCV RNA viral decline of PHX1766, the study in HCV patients demonstrated only modest viral load reduction.

Management of hepatitis C virus genotype 4: recommendations of an international expert panel

HCV has been classified into no fewer than six major genotypes and a series of subtypes. Each HCV genotype is unique with respect to its nucleotide sequence, geographic distribution, and response to therapy. Genotypes 1, 2, and 3 are common throughout North America and Europe. HCV genotype 4 (HCV-4) is common in the Middle East and in Africa, where it is responsible for more than 80% of HCV infections. It has recently spread to several European countries. HCV-4 is considered a major cause of chronic hepatitis, cirrhosis, hepatocellular carcinoma, and liver transplantation in these regions. Although HCV-4 is the cause of approximately 20% of the 170 million cases of chronic hepatitis C in the world, it has not been the subject of widespread research. Therefore, this document, drafted by a panel of international experts, aimed to review current knowledge on the epidemiology, natural history, clinical, histological features, and treatment of HCV-4 infections.

Efficacy and safety of a novel pegylated interferon alpha-2a in Egyptian patients with genotype 4 chronic hepatitis C

BACKGROUND

Hepatitis C virus (HCV) genotype 4 is a common infection in Egypt and is the leading cause of liver disease.

OBJECTIVE

To study the efficacy and safety of a novel 20 kD pegylated interferon alpha-2a derived from Hansenula polymorpha in combination with ribavirin for the treatment of Egyptian patients with genotype 4 chronic hepatitis C (CHC).

METHODS

One hundred seven patients with genotype 4 CHC were involved in the present study. Liver biopsy was performed in all patients. All patients received a fixed weekly dose of 160 µg of a novel pegylated interferon in combination with ribavirin in standard and adjusted doses. Serum HCV RNA levels were assessed by a real-time sensitive polymerase chain reaction assay at four, 12, 48 and 72 weeks after the start of therapy. Patients demonstrating an early virological response (EVR) completed a 48-week course of treatment.

RESULTS

The overall sustained virological response (SVR) was 60.7%. The SVR in patients with a rapid virological response was significantly higher (91.7%) than in patients with complete EVR (67.74%) (P=0.033) and partial EVR (56.14%) (P=0.003). SVR was also significantly higher in patients with a low degree of liver fibrosis according to Metavir score (F1 and F2) (67.57%) compared with those with a high degree of liver fibrosis (F3 and F4) (45.45%) (P=0.017). The baseline viral load had no impact on SVR in the present series nor were any serious adverse events reported.

CONCLUSION

The novel pegylated interferon alpha-2a assessed in the present study was effective for the treatment of patients with genotype 4 CHC, and was safe and well tolerated.

Treatment with peginterferon versus interferon in Chinese patients with chronic hepatitis C

Higher sustained virological response (SVR) rates after treating with peginterferon than after treating with interferon have been obtained in some randomized clinical trials (RCTs) in Chinese patients with chronic hepatitis C (CHC). However, the numbers of patients included in these clinical trials were too small to draw a clear conclusion. Therefore, a new meta-analysis including a large number of patients was needed to compare peginterferon with interferon in the treatment of Chinese CHC patients. A search of Medline, the China National Knowledge Infrastructure, the Wanfang Database, and the China Biomedical Database for relevant articles published between 1966 and 2009 was performed. RCTs comparing the use of peginterferon and interferon for the treatment of Chinese patients with CHC were assessed. Of the 236 studies screened, 18 RCTs including 1,148 patients (659 treated with peginterferon therapy and 489 treated with interferon therapy) were analyzed. The total SVR rates obtained in patients treated with peginterferon were significantly higher than those obtained in patients treated with interferon (64% vs. 40%; relative risk, 1.56; 95% confidence interval: 1.28-1.91; p < 0.01), but the difference between the peginterferon α-2b and interferon α-2b treatments was not significant. Withdrawal rates were similar between patients treated with peginterferon and interferon. Chinese patients with CHC have a greater likelihood of achieving an SVR with peginterferon α-2a.

Thymalfasin in the treatment of hepatitis B and C

Thymalfasin exhibited an immunomodulatory and a direct antiviral mechanism of action. The low rate of sustained response of chronic hepatitis with current therapies, underscores the need for new therapeutic options. It has been suggested that thymalfasin may have efficacy in the treatment of chronic hepatitis B and C. Pilots studies in patients with chronic hepatitis B treated with thymalfasin in combination with interferon or nucleoside analogue, showed a 70% complete sustained response rate. Studies in chronic hepatitis C patients, would indicate that thymalfasin in combination with standard or pegylated interferon with ribavirin may improve response rate in hepatitis C virus (HCV) naïve and nonresponder patients. However, a large phase-III randomized study conducted in Europe in HCV patients nonresponder to Peg-interferon with ribavirin, demonstrated that thymalfasin did not improve the rate of sustained virologic responses, but, in patients who completed therapy, thymalfasin significantly diminished the relapse rate. In conclusion, thymalfasin, in combination with the standard of care, may be helpful as an adjuvant in the treatment of patients with chronic hepatitis B and C.

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.

The neglected hepatitis C virus genotypes 4, 5 and 6: an international consensus report

Abstract Hepatitis C virus (HCV) genotypes 4, 5 and 6 represent >20% of all HCV cases worldwide. HCV-4 is mainly seen in Egypt, where it represents 90% of all HCV cases. Antischistosomal therapy was the main cause of contamination there, followed by procedures performed by informal providers and traditional healers such as dental care, wound treatment, circumcision, deliveries, excision and scarification. It is also highly prevalent in sub-Saharan Africa and in the Middle East. In Europe, its prevalence has recently increased particularly among intravenous drug users and in immigrants. HCV-5 is mainly found in South Africa, where it represents 40% of all HCV genotypes, but four pockets of HCV-5 were found in France, Spain, Syria and Belgium and sporadic cases were found elsewhere. The mode of transmission is mainly iatrogenic and transfusion. HCV-6 is found in Hong Kong, Vietnam, Thailand and Myanmar and also in American and Australian from Asian origin. The response to treatment in HCV-4 is intermediate between HCV-1 and HCV-2 and HCV-3. A sustained viral response is achieved in 43-70% with pegylated interferon and ribavirin. It is higher in Egyptians than Europeans and Africans and is negatively related to insulin resistance and to the severity of fibrosis. It increases to >80% with 24 weeks of therapy only if a rapid virological response is achieved. In HCV-5, a sustained virological response is achieved in >60% with 48 weeks of therapy. HCV-6 is also considered an easy-to-treat genotype, leading to a response in 60-85% of cases.

Current challenges in viral hepatitis, antimicrobial resistance and the influenza pandemic

The 3rd Ditan International Conference on Infectious Diseases was held from 29 July to 2 August 2009 at the Beijing International Conference Center, Beijing, China. Over 1000 participants from 27 countries attended the 4-day conference, titled 'World Dialogue on Infectious Diseases'. A broad range of topics were covered this year, including TB, methicillin-resistant Staphylococcus aureus, HIV, influenza and gastrointestinal infections. In addition, there was a particularly strong focus on two contrasting topics of viral hepatitis and antibiotic resistance, which is the focus of this meeting report.

Impact of obesity, steatosis and insulin resistance on progression and response to therapy of hepatitis C

Clinical progression of chronic hepatitis C depends on several cofactors, which also have a negative affect on the rate of response to interferon-alpha-based therapy. Given the current worldwide prevalence of the metabolic syndrome, the impact of obesity and insulin resistance, and of their histopathological correlate, hepatic steatosis, on the natural history and management of chronic hepatitis C is undoubtedly very important. We will review some of the current knowledge on the clinical consequences of overweight/obesity, steatosis and insulin resistance on chronic hepatitis C, and discuss how this issue may be dealt with in clinical practice.

Response to pegylated interferon alfa-2a and ribavirin in chronic hepatitis C genotype 4

The safety and efficacy of pegylated interferon (PEG-IFN) alfa-2a and ribavirin were studied among patients treated for genotype 4 chronic hepatitis C. Ninety-five patients with chronic hepatitis C genotype 4 were treated with PEG-IFN alfa-2a (180 microg/week) plus ribavirin (> or =11 mg/kg/day) for 48 weeks. The primary end point was sustained virological response, defined as non-detectable levels of HCV RNA at the end of follow up (week 72). The proportion with sustained virological response was 58/95 = 61.1% (95% CI = 50.5-70.9%). Side effects were generally mild, well managed by dose reductions (in 62% of patients); in only two patients were side effects sufficiently severe to require treatment interruption. Ninety percent of patients adhered to treatment up to week 12, and their sustained virological response rate was higher compared to non-adherent (65% vs. 22%, respectively, P = 0.012). None of the patients who failed to achieve 1 log reduction of viral load by week 8 (n = 15), or 2 log reduction by week 12 (n = 17), had a sustained virological response. In conclusion, sustained virological response in genotype 4 Egyptian patients treated with PEG-IFN alfa-2a and ribavirin was estimated around 60%, intermediate between sustained virological response observed in genotype 1 and genotype 2-3 patients in Western countries. The early virological response (week 4 or week 8) should be investigated as a criterion to decide whether the patient may benefit from a shorter duration of therapy.

Sustained virological response in a predominantly hepatitis C virus genotype 4 infected population

AIM: To assess sustained virological response (SVR) rates in a predominantly hepatitis C virus (HCV) genotype 4 infected population.

METHODS: Between 2003-2007, 240 patients who were treated for chronic hepatitis C infection at our center were included. Epidemiological data, viral genotypes, and treatment outcomes were evaluated in all treated patients. Patients with chronic renal failure, previous non-responders, and those who relapsed after previous treatment were excluded from the study. Among all patients, 57% were treated with PEG-interferon (IFN) α-2a and 43% patients were treated with PEG-IFN α-2b; both groups received a standard dose of ribavirin.

RESULTS: 89.6% of patients completed the treatment with an overall SVR rate of 58%. The SVR rate was 54% in genotype 1, 44% in genotype 2, 73% in genotype 3, and 59% in genotype 4 patients. There was no statistical difference in the SVR rate between patients treated with PEG-IFN α-2a and PEG-IFN α-2b (61.5% vs 53%). Patients younger than 40 years had higher SVR rates than older patients (75% vs 51%, P = 0.001). SVR was also statistically significantly higher when the HCV RNA load (pretreatment) was below 800.000 (64% vs 50%, P = 0.023), in patients with a body mass index (BMI) less than 28 (65% vs 49%, P = 0.01), and in patients who completed the treatment duration (64% vs 8%, P ≤ 0.00001).

CONCLUSION: The SVR rate in our study is higher than in previous studies. Compliance with the standard duration of treatment, higher ribavirin dose, younger age, lower BMI, and low pretreatment RNA levels were associated with a higher virological response.

Predicting the probable outcome of treatment in HCV patients

Hepatitis C virus (HCV) is a major cause of chronic liver disease infecting more than 170 million people worldwide. HCV produces a wide gamut of manifestations varying from mild self-limiting disease to cirrhosis and hepatocellular carcinoma. A variety of viral, environmental and host genetic factors contribute to the clinical spectrum of patients infected with HCV and influence response to interferon (IFN) therapy. Predicting the probable outcome of treatment in patients with HCV infection has always been a challenging task. Treatment of HCV by pegylated interferon (peg-IFN) plus ribavirin eradicates the virus in approximately 60% of patients - HCV genotype 1 (42-51% response rates) and genotypes 2 and 3 (76-84% response rates); however, a significant number of patients do not respond to therapy or relapse following discontinuation of treatment or have significant side effects that preclude further treatment. Accurately predicting the patients who will respond to therapy is becoming increasingly important, both from the point of patient care and also with respect to the healthcare cost as clinicians need to continue treatment in patients who will respond and stop treatment in patients who are unlikely to respond. Viral RNA measurements and genotyping are used to optimize treatment as a low viral load and nongenotype 1 is more likely to be associated with sustained virological response (SVR). Rapid virological response (RVR) defined by undetectable HCV RNA at 4 weeks of treatment is increasingly being recognized as a powerful tool for predicting treatment response. A variety of host factors including single nuclear polymorphisms (SNPs) of IFN response genes, insulin resistance, obesity, ethnicity, human leukocyte antigens and difference in T-cell immune response has been found to modulate the response to antiviral treatment. The presence of severe fibrosis/cirrhosis on pretreatment liver biopsy predicts a poor response to treatment. Recent studies on gene expression profiling and characterization of the liver and serum proteome provide options to accurately predict the outcome of patients infected with HCV in the future. Future studies on the factors that predict treatment response and tailoring treatment based on this is required if we are to conquer this disease.

Long-term outcomes after treatment with interferon and ribavirin in HCV patients

Hepatitis C is a leading indication for transplantation and a common cause of liver-related death worldwide. Treatment for hepatitis C has evolved from interferon therapy alone, which yielded relatively poor response rates compared with the currently recommended and more effective combination of pegylated interferon and ribavirin. Factors such as hepatitis C viral genotype, pretreatment viral load, race, renal function, degree of hepatic fibrosis, and comorbid conditions such as HIV coinfection have clinical importance in that they influence viral kinetics, which play a large role in determining a sustained response to therapy or virologic "cure." However, the goal of therapy is to reduce liver-related morbidity and mortality by decreasing rates of progression or improvement of fibrosis, reducing risk of hepatocellular carcinoma, improving posttransplant graft and patient survival, and resolving or improving some of the extrahepatic manifestations of hepatitis C. Studies generally infer long-term success from the more tangible goal of sustained viral suppression; however, increasing data suggest that effective therapy does result in decreased morbidity and mortality. Given the heterogeneity of patients who are infected with hepatitis C, treatment decisions should be specifically tailored to each individual patient on the basis of their predisposing conditions and anticipated clinical outcomes.

Predictors of sustained virological response to a 48-week course of pegylated interferon alfa-2a and ribavirin in patients infected with hepatitis C virus genotype 4

BACKGROUND AND OBJECTIVES

Knowledge of the predictors of sustained viral response (SVR) to pegylated interferon (PEG-INF) alfa-2a and ribavirin (RBV) therapy in patients with hepatitis C genotype-4 (HCV-4) is crucial for selecting patients who would benefit most from therapy. We assessed the predictors of SVR to this combination therapy in Saudi patients with chronic HCV-4 infection.

PATIENTS AND METHODS

This retrospective study included 148 patients with HCV-4 infection who underwent clinical, biochemical and virological assessments before treatment and at 12, 24, 48 and 72 weeks post-treatment.

RESULTS

Of the 148 patients, 90 (60.8%) were males. Mean (SD) for age was 48.5 (12.7) years and BMI was 27.9 (7.5) kg/m(2). Seventy-nine of 148 (60.1%) patients were treatment naïve and 110 (74.3%) underwent pre-treatment liver biopsy. Eighteen (12.2%) patients did not complete therapy because of side effects or they were lost to follow up. Early virological response was achieved in 84 of 91 (92.3%) patients. In the 130 (87.8%) patients who completed therapy, 34 (26.2%) were non-responders and 96 (63.8%) achieved end-of-treatment virological response (ETVR). SVR and virological relapse (24 weeks after ETVR) occurred in 66/130 (50.7%) and 30/130 (31.2%) patients, respectively. Compared to relapsers, sustained responders were significantly younger (P=.005), non-diabetic (P=.005), had higher serum albumin (P=.028), lower alpha-fetoprotein level (P=.026), lower aspartate aminotransferase (AST) (P=.04) levels, and were treatment-naïve (P=.008). In a multivariate regression analysis, the independent predictors of SVR were younger age (P=.016), lower serum AST (P=.012), and being treatment naïve (P=.021).

CONCLUSION

Approximately half of HCV-4 patients who complete the course of combination therapy achieve an SVR, especially if they are young, treatment naA ve and have lower AST levels.

Hepatitis C genotype 4 therapy: increasing options and improving outcomes

Hepatitis C virus genotype 4 (HCV-G4) is prevalent in the Middle East and Africa and has spread to several regions in Europe. HCV-G4 represents a major health problem in Egypt, with a prevalence rate of 13%. Recently, HCV-G4 has been spreading in Europe particularly among intravenous drug users (IDU) populations, who represent the main reservoir for HCV in Europe. This article reviews the current therapeutic strategies for HCV-G4 infections in different populations. HCV-G4 has been considered a difficult-to-treat genotype because of the poor sustained virological response (SVR) rates reported with a conventional interferon (IFN)-based regimen. Pegylated IFN and ribavirin combination therapy was associated with significant improvements in SVR rates that currently exceed 60%, particularly with individualized therapy. Lower response rates have been reported in specific situations, namely chronic HCV-G4 infection in IDUs and patients co-infected with human immunodeficiency virus (HIV). Rapid and early virological responses have been useful tools for determination of the duration of therapy.

IN CONCLUSION

therapy of HCV-G4 has shown significant improvements, with higher sustained response rates and possibilities for a shorter duration. More research is required to optimize therapy in special populations such as IDUs and HIV-co-infected patients.

Treatment predictors of a sustained virologic response in hepatitis B and C

Treatment predictors are important tools for the management of therapy in patients with chronic hepatitis B and C virus (HBV, HCV) infection. In chronic hepatitis B, several pretreatment parameters have been identified for prediction of virologic response to interferon alfa-based antiviral therapies or treatment with polymerase inhibitors. In interferon alfa and pegylated interferon alfa-treated patients, low baseline HBV DNA concentrations, HBV genotype A (B), and high baseline ALT levels are significantly associated with treatment response. In patients treated with nucleos(t)ide analogues, low baseline HBV DNA but not viral genotype is positively associated with virologic response. During treatment the best predictor of response is HBV DNA kinetics. Early viral suppression is associated with favourable virologic response and reduced risk for subsequent resistance mutations. For the current standard treatment with pegylated interferon alfa and ribavirin in patients with chronic hepatitis C, infection with HCV genotypes 2 and 3, baseline viral load below 400,000-800,000 IU/ml, Asian and Caucasian ethnicity, younger age, low GGT levels, absence of advanced fibrosis/cirrhosis, and absence of steatosis in the liver have been identified as independent pretreatment predictors of a sustained virologic response. After initiation of treatment, initial viral decline with undetectable HCV-RNA at week 4 of therapy (RVR) is the best predictor of sustained virologic response independent of HCV genotype.