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

Simple predictors of nonresponse to direct-acting antivirals in chronic hepatitis C patients

OBJECTIVES

The introduction of direct acting antivirals (DAAs) has resulted in very high sustained virological response rates (SVR) in patients with chronic hepatitis-C (CHC). There are still a minority who fails to achieve SVR. This study aims to identify simple factors associated with nonresponse to DAAs using routine pretreatment workup.

METHODS

A retrospective study included 10 655 CHC patients who were candidates for anti-viral therapy. Pretreatment demographics, laboratory results, ultrasonography and FIB-4were obtained.

RESULTS

At post-treatment week 4, 10 495 patients (98.5%) were responders and 160 (1.5%) were non-responders. About 50.6% of non-responders were males and 61.3% were cirrhotic. Non-responders had significantly higher baseline BMI, liver enzymes, AFP and a significantly lower albumin, platelet count by univariate analysis ((P < 0.001). Sex, previous treatment, BMI, liver cirrhosis, AST, Albumin and platelet counts were the independent predictors of non-response. At post-treatment week 12, HCV-PCR results were available only for 7259 patients and 210 (2.9%) were non-responders. 54.8% of non-responders were cirrhotic and 51.4% were males. Non-responders had significantly higher AST, AFP and INR and a significantly lower albumin level, platelet count by univariate analysis (P < 0.05). Sex, previous treatment, AST, Albumin, WBC and platelet counts were the independent predictors of non-response. SVR-4 among treatment naive patients was 98.6% while among treatment experienced was 96.8%. SVR-12 among treatment naive patients was 97.9% while among treatment experienced was 87.9%.Cirrhotics had SVR-4 rate 97.7% and SVR-12 rate 96.21%.

CONCLUSION

Routine pre-treatment work up for HCV G4 patients receiving DAAs can help in prediction of non-response.

Factors Affecting the Virological Response Among Chronic Hepatitis C Virus Patients in Yemen

Hepatitis C virus (HCV) infection is increasingly seen as a major public health problem, threat, and concern worldwide. In Yemen about 1.7% of the population is infected with chronic hepatitis C. This study aimed to detect the predictors for response to pegylated interferon and ribavirin (Peg-IFN/RBV) in chronic HCV Yemeni patients. The study was conducted on 100 patients with chronic HCV who received Peg-IFN/RBV in the 48th Military Hospital in Sana'a Yemen, from 2011 to 2013. All patients were subjected to complete history taking, thorough clinical examinations, routine laboratory investigation, and abdominal ultrasonography. The HCV RNA was assessed at week 72 of treatment to detect whether the patient achieved sustained virological response (SVR). The SVR was achieved in 64% of the samples. Age above 40, Khat chewing, and obesity were the sociodemographic factors that predict good response for Peg-IFN/RBV combined therapy. Platelet count, alpha feto-protein (AFP), aspartate transaminase (AST), and alanine transaminase (ALT) levels were the basic laboratory investigations that gave favorable response. Significant predictors of sustained response included: older than 40 years (OR = 0.136, P = 0.042), Khat chewer (OR = 0.016, P = 0.008), body mass index (BMI) (OR = 0.055, P = 0.029) and increase in fasting blood glucose (OR = 0.925, P = 0.004), alkaline phosphatase (OR = 0.969, P = 0.001), total and bilirubin (OR = 0.058, P = 0.017), AST (OR = 1.033, P = 0.002), and albumin (OR = 6.490, P = 0.021). Studying the independent variables of response, we revealed that male gender, BMI, ALT >40, AFP >10, viremia >600, and hemoglobin and thyroid stimulating hormone (TSH) levels are variables associated with failure of end of treatment response (ETR) and SVR.

The role of hepatic progenitor cells in predicting response to therapy in Egyptian patients with chronic hepatitis C, genotype 4

Background

Interferon therapy is used as a line of treatment of chronic hepatitis C virus (HCV) in several areas of the world including Egypt.

Objective

Our aim was to investigate the value of hepatic progenitor cells (HPCs) in predicting response of patients with chronic HCV, genotype 4 to pegylated interferon (PEGIFN) plus ribavirin (RBV) therapy.

Methods

Pre-treatment liver biopsies obtained from 110 patients with chronic HCV, genotype 4 were examined immunohistochemically for HPCs using cytokeratin19. The mean number of HPCs as ductular reaction (DR) and as isolated progenitor cells (IPCs) was counted in each case. The patients were classified into: those with sustained virological response (SVR) and those who did not achieve SVR. The results were compared between the two groups. Also, the relationships between HPCs and other clinico-pathologic variables were estimated using multivariate analysis.

Results

The mean number of HPCs was the only independent predictor of therapeutic response, being significantly higher in non-responders (P = 0 for DR and P = 0.03 for IPCs). On the other hand, fibrosis stage and steatosis were the only independent factors which showed a significant direct association with the mean number of HPCs in the form of DR and IPCs (P = 0 for each).

Conclusion

The number of HPCs provides prognostic information in chronic HCV since it is significantly associated with stage of fibrosis. More importantly, it can be used as a marker to predict response of patients with chronic HCV to PEGIFN plus RBV therapy.

IL-21 as a Predictor of Sustained Virologic Response in Patients with Chronic Hepatitis C Virus Infection

Hepatitis C virus (HCV) infection is a significant public health problem. The crucial role of interleukin (IL)-21 in HCV has been established. Thus, we aimed to investigate the association of serum IL-21 levels with the virological response to interferon (IFN)-based therapy in a group of Egyptian patients with chronic hepatitis C (CHC). Clinical data were collected from 58 HCV-positive Egyptian patients treated with IFN/ribavirin therapy and 10 non-HCV-infected healthy subjects. Liver and renal function tests, complete blood count, viral markers, and pretreatment IL-21 levels were determined in all patients and healthy controls. Patients who achieved sustained virologic response (SVR) had higher pretreatment median serum IL-21 levels than those who did not. Thus, this study concluded that higher pretreatment serum IL-21 may be useful in predicting SVR in CHC patients.

Osteopontin as a marker for response to pegylated interferon Alpha-2b treatment in Chronic HCV Saudi patients

BACKGROUND

Many recent studies support the idea that osteopontin (OPN) can be used to predict the success of pegylated interferon (PEG IFN) alpha-2b/ribavirin therapy in chronic HCV patients.

OBJECTIVE

Our aim was to investigate the role of plasma OPN and its gene polymorphism at nt - 443 in response to PEG IFN in Saudi patients with chronic HCV.

METHODS

Blood was collected from 87 patients with chronic hepatitis C before treatment, then patients received PEG IFN α2b plus ribavirin combination therapy. Another 25 healthy subjects, matched for age and sex to patients, were enrolled as controls. Single nucleotide polymorphism (SNP) in OPN at nt - 443 and its blood level were analyzed.

RESULTS

The frequency of patients who reached sustained virological response (SVR) was increased in patients with T/T at nt - 443 than in those with C/C or C/T. Also the frequency of T allele was increased in responders than in non-responders. However, this increase was not statistically significant. The blood level of OPN was significantly increased in non-responders (Mean±SD=37.21±3.9) in comparison to responders (Mean±SD=33.22±4.1).

CONCLUSION

Osteopontin blood level can be considered as a reliable predictor to PEG IFN α2b plus ribavirin therapy in chronic HCV Saudi Patients.

Tracing the epidemic history of hepatitis C virus genotypes in Saudi Arabia

HCV genotype 4 is highly prevalent in many Middle Eastern countries, yet little is known about the genotype's epidemic history at the subtype-level in this region. To address the dearth of data from Saudi Arabia (SA) we genotyped 230 HCV isolates in the core/E- and NS5B-region and analyzed using Bayesian phylogenetic approaches. HCV genotype 4 (HCV/4) was positive in 61.7% (142/230) of isolates belonging to 7 different subtypes with the predominance of 4d (73/142; 51.4%) followed by 4a (51/142; 35.9%). Phylogenetic analysis also revealed a distinct epidemiological cluster of HCV/4d for Saudi Arabia. HCV/1 appeared as the second most prevalent genotype positive in 31.3% (72/230) of isolates with the predominance of 1b (53/72; 73.6%) followed by 1a (16/72; 22.2%), and 1g (3/72; 4.1%). A small proportion of isolates belonged to HCV/3a (12/230; 5.2%), and HCV/2a (4/230; 1.7%). We estimate that the genotype 4 common ancestor existed around 1935 (1850-1985). Genotype 4 originated plausibly in Central Africa and multiple subtypes disseminated across African borders since ~1970, including subtype 4d which dominates current HCV infections in Saudi Arabia. The Bayesian skyline plot (BSP) analysis showed that genotype 4d entered the Saudi population in 1900. The effective number of HCV infections grew gradually until the second half of the 1950s and more rapidly until the early-80s through the use of imported blood units and blood products. Subsequently, the rate of HCV infection in the Saudi Arabian population was stabilized through effective screening of blood and infection control measures.

Magnitude and causes of loss to follow-up among patients with viral hepatitis at a tertiary care hospital in Saudi Arabia

BACKGROUND

Non-adherence with recommended follow-up visits is a major barrier for completing treatment of viral hepatitis and is consequently associated with unfavorable outcomes of health services.

OBJECTIVES

To estimate the magnitude and identify perceived reasons and patient characteristics associated with loss to follow-up in a tertiary care setting.

METHODS

A two-step cross-sectional study design was used, including a chart review (2011) followed by phone survey (2012). Loss to follow-up was recorded among those who were diagnosed with hepatitis B (HBV) or C (HCV) during 2009-2010 but never returned for recommended/scheduled follow-up appointment(s).

RESULTS

A total of 328 patients (202 HBV and 126 HCV) were included in the current analysis. The average age was 49.6±17.9years, and 57% were males. Out of 328, 131 (40%) were not advised to do follow-up, and 98 (30%) were not doing follow-up. Perceived reasons for loss to follow-up were as follows: unaware that a follow-up appointment was scheduled (69%), never informed of need for follow-up by healthcare provider (15%), personal belief that follow-up was not necessary (9%), logistical reasons (3%) and other reasons (5%). Loss to follow-up was higher among those who had been diagnosed with HBV, referred by non-liver-related specialty, never advised to follow-up, unaware of their diagnosis, incorrectly identified their type of hepatitis, lacking hepatitis complications, having full medical coverage, pregnant, and those with low knowledge or negative attitude towards hepatitis.

CONCLUSIONS

Loss to follow-up is a significant problem among patients with hepatitis in a tertiary care center, with several patient and system failures being implicated.

Investigation of NS3 Protease Resistance-Associated Variants and Phenotypes for the Prediction of Treatment Response to HCV Triple Therapy

Triple therapy of chronic hepatitis C virus (HCV) infection with boceprevir (BOC) or telaprevir (TVR) leads to virologic failure in many patients which is often associated with the selection of resistance-associated variants (RAVs). These resistance profiles are of importance for the selection of potential rescue treatment options. In this study, we sequenced baseline NS3 RAVs population-based and investigated the sensitivity of NS3 phenotypes in an HCV replicon assay together with clinical factors for a prediction of treatment response in a cohort of 165 German and Swiss patients treated with a BOC or TVR-based triple therapy. Overall, the prevalence of baseline RAVs was low, although the frequency of RAVs was higher in patients with virologic failure compared to those who achieved a sustained virologic response (SVR) (7% versus 1%, P = 0.06). The occurrence of RAVs was associated with a resistant NS3 quasispecies phenotype (P<0.001), but the sensitivity of phenotypes was not associated with treatment outcome (P = 0.2). The majority of single viral and host predictors of SVR was only weakly associated with treatment response. In multivariate analyses, low AST levels, female sex and an IFNL4 CC genotype were independently associated with SVR. However, a combined analysis of negative predictors revealed a significantly lower overall number of negative predictors in patients with SVR in comparison to individuals with virologic failure (P<0.0001) and the presence of 2 or less negative predictors was indicative for SVR. These results demonstrate that most single baseline viral and host parameters have a weak influence on the response to triple therapy, whereas the overall number of negative predictors has a high predictive value for SVR.

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.

Re-treatment of patients with chronic hepatitis C virus genotype 4 infection with pegylated interferon and ribavirin: a meta-analysis

BACKGROUND

An estimated 170 million people worldwide are infected with hepatitis C virus (HCV). HCV genotype 4 (HCV-4)-the most prevalent hepatitis C strain in the Middle East and Africa-is difficult to treat, with an estimated sustained virological response (SVR) of 53% when using pegylated interferon and ribavirin (P/R) in treatment-naïve patients with HCV-4 infection. In regions where access to direct-acting antivirals is limited, re-treatment of patients who failed therapy with another course of P/R may be an option if the success rate is acceptable.

OBJECTIVES

We aimed to determine the SVR from retreatment with P/R in treatment-experienced patients with HCV-4 infection.

METHODS

We performed a meta-analysis using MEDLINE and EMBASE searches, and by reviewing article bibliographies and abstracts from recent Liver Society Meetings. Original studies featuring at least 10 adult, treatment-experienced patients with HCV-4 infection failing prior interferon-based therapy and receiving subsequent re-treatment with P/R were included.

RESULTS

3 studies were included. Overall pooled SVR was 32.7%, or 41/126 patients. No significant heterogeneity existed among the studies. One study reported higher SVR of 50% in previous relapsers, compared with 23% in previous non-responders.

CONCLUSIONS

As expected, treatment-experienced patients achieved lower rate of SVR compared with previously reported SVR for treatment-naïve patients with HCV-4 infection. The abysmal rate of success from re-treatment with P/R supports the use of direct-acting antivirals whenever re-treatment is considered, even in resource-limited regions.

Assessment of interleukin 28B genotype as a predictor of response to combined therapy with pegylated interferon plus ribavirin in HCV infected Egyptian patients

BACKGROUND AND AIM

Single nucleotide polymorphisms (SNPs) of interleukin 28B (IL28B) gene is associated with spontaneous clearance and variable response to combined therapy with pegylated interferon (PEG-IFN) and ribavirin (RBV) in chronic hepatitis C virus (HCV) infected patients. This study aimed at assessing the value of IL28B rs8099917 gene polymorphism in predicting sustained virological response (SVR) among HCV infected Egyptian patients treated with PEG-IFN and RBV.

METHODS

Our study was conducted on 153 chronic HCV infected patients treated with PEG-IFN and RBV. Genotyping of rs8099917 near the IL-28B gene was performed by Real Time PCR using Taq-Man probe assay.

RESULTS

The overall SVR was achieved in 49.6% of patients. Patients with TT genotype showed significantly higher SVR rate than minor allele (TG/GG) carriers (74% vs. 26%, P=0.004). Logistic regression analysis revealed that TT carriers had 2.8 higher chance for SVR achievement than G allele carriers TG/GG (OR=2.8, 95% CI=1.4-5.6, P=0.004). Younger age, male sex and low activity grading were significant predictors of SVR (P=0.003, P=<0.001 and P<0.001 respectively). High pretreatment AST levels and advanced liver fibrosis were negative predictors of SVR (P=0.04 and P<0.001 respectively).

CONCLUSION

IL28B genotype is a significant pre-treatment predictor of response to PEG-IFN/RBV in HCV infected Egyptian patients.

Relation of ALT and AST levels to the histopathological changes in liver biopsies of patients with chronic hepatitis C genotype 4

BACKGROUND AND STUDY AIMS

Worldwide, Egypt has a high prevalence of adult hepatitis C virus (HCV) infection. Serum alanine aminotransferase (ALT) activity is most commonly measured to assess hepatic disease. The revision of the definition of the normal limits for the ALT level is advisable. The aim of this work was to compare the histopathological changes in the liver tissue biopsies of HCV-infected patients, clinically presenting with ALT levels below normal, based on the conventional, previously used upper limit of normal (ULN) of ALT (40U/L for men and 30U/L for women) with the proposed new ULN (30U/L for men, and 19U/L for women).

PATIENTS AND METHODS

This is a retrospective cross-sectional study. A total of 668 cases of chronic hepatitis C genotype 4 were included. Patients were classified according to grades of histological activity and fibrosis stages (by the Metavir scoring system). They were also classified into normal and high groups according to the old and new cutoffs of both aspartate transaminase (AST) and ALT levels.

RESULTS

The results of our study showed that the serum AST level in our study showed a better correlation with the histopathological changes in liver biopsy rather than ALT, especially when using the old cutoff of the ULN for AST. The serum ALT level in our study (both the old and the new cutoffs) did not show a significant correlation with the histopathological status in the liver biopsies of our patients.

CONCLUSION

This study concluded that the old cutoff of the ULN AST is a better predictor of fibrosis.

Sustained virological response and its treatment predictors in hepatitis C virus genotype 4 compared to genotypes 1, 2, and 3: a meta-analysis

BACKGROUND

Pegylated interferon and ribavirin (PEG-IFN+RBV) may be more cost-effective than direct-acting antivirals in resource-limited settings. Current literature suggests sustained virological response (SVR) in hepatitis C virus genotype 4 (HCV-4) is similar to genotype 1 (HCV-1), but worse than 2 and 3 (HCV-2/3). However, few studies have compared treatment response between these groups and these have been limited by small sample sizes with heterogeneous designs. We performed a meta-analysis of SVR predictors in HCV-4 versus HCV-1, 2, and 3 patients treated with PEG-IFN+RBV.

METHODS

In November 2013, we searched for 'genotype 4' in MEDLINE/EMBASE databases and scientific conferences. We included original articles with ≥25 treatment-naïve HCV-4 and comparisons to HCV-1, 2, and/or 3 patients treated with PEG-IFN+RBV. Random effects modelling was used with heterogeneity defined by Cochrane Q-test (p value<0.10) and I(2) statistic (>50%).

RESULTS

Five studies with 20 014 patients (899 HCV-4; 12 033 HCV-1; and 7082 HCV-2/3 patients) were included. SVR was 53% (CI 43% to 62%) for HCV-4, 44% (CI 40% to 47%) for HCV-1; and 73% (CI 58% to 84%) for HCV-2/3. SVR with EVR (early virological response) was 75% (CI 61% to 86%) in HCV-4; 64% (CI 46% to 79%) in HCV-1; and 85% (CI 71% to 93%) in HCV-2/3. SVR without EVR was 10% (CI 6% to 17%) for HCV-4; 13% (CI 12% to 15%) for HCV-1; and 23% (CI 16% to 33%) for HCV-2/3.

CONCLUSIONS

SVR rates are similar in HCV-4 (∼50%) and HCV-1 (∼40%). Lack of EVR is a good stopping rule for HCV-4 and HCV-1 since only 10% subsequently achieve SVR. In HCV-4 patients with EVR, three-quarters can expect to achieve SVR with PEG-IFN+RBV.

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.

Predicting the outcomes of combination therapy in patients with chronic hepatitis C using artificial neural network

BACKGROUND

Treatment with Peginterferon Alpha-2b plus Ribavirin is the current standard therapy for chronic hepatitis C (CHC). However, many host related and viral parameters are associated with different outcomes of combination therapy.

OBJECTIVES

The aim of this study was to develop an artificial neural network (ANN) model to predetermine individual responses to therapy based on patient's demographics and laboratory data.

PATIENTS AND METHODS

This case-control study was conducted in Tehran, Iran, on 139 patients divided into sustained virologic response (SVR) (n = 50), relapse (n = 50) and non-response (n = 39) groups according to their response to combination therapy for 48 weeks. The ANN was trained 300 times (epochs) using clinical data. To test the ANN performance, the part of data that was selected randomly and not used in training process was entered to the ANN and the outputs were compared with real data.

RESULTS

Hemoglobin (P < 0.001), cholesterol (P = 0.001) and IL-28b genotype (P = 0.002) values had significant differences between the three groups. Significant predictive factor(s) for each group were hemoglobin for SVR (OR: 1.517; 95% CI: 1.233-1.868; P < 0.001), IL-28b genotype for relapse (OR: 0.577; 95% CI: 0.339-0.981; P = 0.041) and hemoglobin (OR: 0.824; 95% CI: 0.693-0.980; P = 0.017) and IL-28b genotype (OR: 2.584; 95% CI: 1.430-4.668;P = 0.001) for non-response. The accuracy of ANN to predict SVR, relapse and non-response were 93%, 90%, and 90%, respectively.

CONCLUSIONS

Using baseline laboratory data and host characteristics, ANN has been shown as an accurate model to predict treatment outcome, which can lead to appropriate decision making and decrease the frequency of ineffective treatment in patients with chronic hepatitis C virus (HCV) infection.

Hepatic fibrosis and serum alpha-fetoprotein (AFP) as predictors of response to HCV treatment and factors associated with serum AFP normalisation after treatment

BACKGROUND AND STUDY AIM

Elevated levels of alpha-fetoprotein (AFP) can be seen in patients with chronic hepatitis C (CHC) and liver cirrhosis without hepatocellular carcinoma and were negatively associated with treatment response. However, factors associated with its changes are not identified. We aimed in this study to verify a cut-off value for AFP as a predictor of response to standard of care (SOC) antiviral therapy in Egyptian chronic hepatitis C virus (HCV)-infected patients and identify factors associated with its changes post treatment.

PATIENTS AND METHODS

A total of 175 chronic non-cirrhotic HCV-infected patients were evaluated for baseline serum AFP and liver biopsy were classified according to Ishak scoring system of hepatic fibrosis. All patients were scheduled to receive SOC antiviral therapy for 48weeks and had been followed up to week 72. Reassessment of AFP and repeated liver biopsy at week 72 were feasible only in 79 patients.

RESULTS

High baseline AFP levels were observed in non-respondents (non-sustained virological respondents (non-SVRs)) (P<0.01); the AFP level decreased in all patients post treatment (P=0.01), especially in the SVRs (P<0.01). In multivariate analysis, hepatic fibrosis was a predictor of response to treatment (P=0.02), while body mass index (BMI) (25-30kgm(-2)), hepatic activity (A2), hepatic fibrosis stage (F2-F4) and fibrosis improvement were predictors of AFP difference (P=0.007, 0.01, 0.012, <0.001, 0.030, and 0.018), respectively. The diagnostic performance to predict the HCV treatment response was best by adding both AFP and hepatic fibrosis stage factors; the best cut-off value for AFP was 3.57ngdl(-1) with 50% sensitivity and 68% specificity with area under the curve (AUC) of 0.55 and for hepatic fibrosis stage was 3, with a sensitivity of 88%, a specificity of 30% with an AUC of 0.58.

CONCLUSION

In chronic HCV-infected patients, serum AFP below 3.57ngdl(-1) and hepatic fibrosis ⩽stage 3 are expected to have good response to treatment; BMI (25-30kgm(-1)), A2, fibrosis >2 and fibrosis improvement predict AFP change post treatment.

The impact of interleukin 28b gene polymorphism on the virological response to combined pegylated interferon and ribavirin therapy in chronic HCV genotype 4 infected egyptian patients using data mining analysis

BACKGROUND

Chronic HCV represents one of the common causes of chronic liver disease worldwide with Egypt having the highest prevalence, namely genotype 4. Interleukin IL-28B gene polymorphism has been shown to relate to HCV treatment response, mainly in genotype1.

OBJECTIVES

We aim to evaluate the predictive power of the rs12979860 IL28B SNP and its protein for treatment response in genotype 4 Egyptian patients by regression analysis and decision tree analysis.

PATIENTS AND METHODS

The study included 263 chronic HCV Egyptian patients receiving peg-interferon and ribavirin therapy. Patients were classified into 3 groups; non responders (83patients), relapsers (76patients) and sustained virological responders (104 patients). Serum IL 28 B was performed, DNA was extracted and analyzed by direct sequencing of the SNP rs 12979860 of IL28B gene.

RESULTS

CT, CC and TT represented 56 %, 25 % and 19% of the patients, respectively. Absence of C allele (TT genotype) was significantly correlated with the early failure of response while CC was associated with sustained virological response. The decision tree showed that baseline alpha fetoprotein (AFP ≤ 2.68 ng/ml) was the variable of initial split (the strongest predictor of response) confirmed by regression analysis. Patients with TT genotype had the highest probability of failure of response.

CONCLUSIONS

Absence of the C allele was significantly associated with failure of response. The presence of C allele was associated with a favorable outcome. AFP is a strong baseline predictor of HCV treatment response. A decision tree model is useful for predicting the probability of response to therapy.

The natural history and long-term outcomes in patients with chronic hepatitis C genotype 4 after interferon-based therapy

BACKGROUND & AIMS

Hepatitis C virus (HCV) genotype 4 (G4) infection is common in the Middle East. Post-treatment long-term outcomes have not been reported in these patients. This study evaluates these outcomes in patients after interferon-based therapy.

PATIENTS AND METHODS

A total of 157 patients were followed from June 2001 to February 2012. Descriptive and analytical statistics, cumulative outcomes and the independent predictors of disease progression were calculated.

RESULTS

The overall age was 48.0 ± 11.8 years, 75 (47.8%) were males and 53 (70.7%) of 75 who were genotyped had G4. The follow-up period was 63.8 ± 32.8 months. Sustained virological response (SVR) was achieved in 62 (39.5%) and 24 (45.3%) patients in the whole group and the G4 subgroup respectively. Among the whole cohort and the G4 subgroup, disease progressed in 59 (37.6%) and 21 (39.6%), respectively, with less progression in the SVR groups; 15/62 (24.2%) and 3/24 (12.5%) compared with non-responders; 44 (46.3%) and 18 (62.1%) with P = 0.01 and 0.001 respectively. Multivariate logistic regression analysis showed that having diabetes mellitus (P = 0.03), higher baseline APRI score (P = 0.00) and non-SVR (P = 0.00) were independent predictors of disease progression. G4 patients showed similar results, but 'non-SVR' (P = 0.00) was the only independent predictor of progression. Eight patients died and four developed HCC all among the non-SVR group only.

CONCLUSIONS

This study describes, for the first time, the natural history and demonstrates the beneficial long-term effects of interferon-based therapy in HCV G4 patients.

Prediction of sustained virologic responses to combination therapy of pegylated interferon-α and ribavirin in patients with chronic hepatitis C infection

BACKGROUND AND AIM

Hepatitis C virus (HCV) infection is a major health problem worldwide. Genotype-4 is the most common genotype in Saudi Arabia. The response to treatment with pegylated interferon-α combined with ribavirin in chronic HCV infection varies. This study aimed at investigating the pre- and on-treatment predictors of sustained virologic response (SVR) in patients with chronic hepatitis C (CHC) infection.

PATIENTS AND METHODS

Clinical data of 48 patients with CHC treated with standard HCV antiviral combination therapy, between January 2005 and December 2010, at a Saudi University hospital, were retrospectively reviewed for age, sex, body mass index, liver enzymes, HCV-RNA viral load, liver biopsy, and response to treatment. The primary end point was SVR defined as undetectable HCV-RNA by polymerase chain reaction (PCR) 24 weeks after the end of treatment. Univariable logistic regression was used to explore the association between the different variables and SVR. These independent predictors of SVR were then analyzed with multivariable logistic regression analysis.

RESULTS

Of the 48 treated patients, 25 (52%) were females and 27 (56%) were Saudi. The mean age was 43 years (43 ± 10 years). Twenty-four (50%) had genotype-4, and 26 (54%) had liver biopsy. The overall SVR rate was 75% (36/48) and was 83.3% (20/24) among genotype-4 patients. Baseline factors associated with SVR identified by univariate logistic regression were genotype-4 and early viral response (EVR), defined as a drop of ≥2 log in serum HCV viral load after 12 weeks of initiation of combination therapy (P = 0.001). However, in stepwise regression analysis, the independent factor associated with the effect of antiviral therapy was genotype-4. When on-treatment variables were included, EVR (P = 0.003) and low baseline viral load (P = 0.048) were highly predictive of SVR.

CONCLUSIONS

Of our HCV-treated patients, 75% had SVR. HCV genotype-4, EVR, and low baseline viral load were predictive of SVR.

Prediction of sustained virologic responses to combination therapy of pegylated interferon-α and ribavirin in patients with chronic hepatitis C infection

BACKGROUND AND AIM

Hepatitis C virus (HCV) infection is a major health problem worldwide. Genotype-4 is the most common genotype in Saudi Arabia. The response to treatment with pegylated interferon-α combined with ribavirin in chronic HCV infection varies. This study aimed at investigating the pre- and on-treatment predictors of sustained virologic response (SVR) in patients with chronic hepatitis C (CHC) infection.

PATIENTS AND METHODS

Clinical data of 48 patients with CHC treated with standard HCV antiviral combination therapy, between January 2005 and December 2010, at a Saudi University hospital, were retrospectively reviewed for age, sex, body mass index, liver enzymes, HCV-RNA viral load, liver biopsy, and response to treatment. The primary end point was SVR defined as undetectable HCV-RNA by polymerase chain reaction (PCR) 24 weeks after the end of treatment. Univariable logistic regression was used to explore the association between the different variables and SVR. These independent predictors of SVR were then analyzed with multivariable logistic regression analysis.

RESULTS

Of the 48 treated patients, 25 (52%) were females and 27 (56%) were Saudi. The mean age was 43 years (43 ± 10 years). Twenty-four (50%) had genotype-4, and 26 (54%) had liver biopsy. The overall SVR rate was 75% (36/48) and was 83.3% (20/24) among genotype-4 patients. Baseline factors associated with SVR identified by univariate logistic regression were genotype-4 and early viral response (EVR), defined as a drop of ≥2 log in serum HCV viral load after 12 weeks of initiation of combination therapy (P = 0.001). However, in stepwise regression analysis, the independent factor associated with the effect of antiviral therapy was genotype-4. When on-treatment variables were included, EVR (P = 0.003) and low baseline viral load (P = 0.048) were highly predictive of SVR.

CONCLUSIONS

Of our HCV-treated patients, 75% had SVR. HCV genotype-4, EVR, and low baseline viral load were predictive of SVR.

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.

Hepatitis C genotype 4: genotypic diversity, epidemiological profile, and clinical relevance of subtypes in Saudi Arabia

BACKGROUND/AIM

Hepatitis C virus genotypes 4 (HCV-4) is the most prevalent genotype in Saudi Arabia, although it's various subtypes, mode and route of transmission remains unknown. The aim of this study was to analyze (i) the variability of the HCV-4 subtypes, the route and source of HCV transmission and (ii) the influence of HCV-4 subtypes on their therapeutic response.

PATIENTS AND METHODS

Sixty-four HCV-4 patients were analyzed retrospectively for the prevalence of various sub-genotypes and the possible mode of transmission, and it was correlated with their treatment response to pegylated interferon (PEG-IFN) α-2a and ribavirin therapy.

RESULTS

Positive history of blood or blood products transfusion was noted in 22 patients (34%), hemodialysis in 10 patients (15.6%), surgery in 7 patients (11%), and unknown etiology in 25 patients (39%). Prevalence of HCV-4 subtypes was 4a = 48.4% (31/64), 4d = 39% (25/64), 4n = 6.25% (4/64), and remaining combined (4m, 4l, 4r, 4o) 6.25% (4/64). No significant correlation between subtypes and the source of transmission was recognized ( P = 0.62). Sustained virological response in all HCV-4 patients was 64% (41/64), while in each subtypes separately it was 4a 77.4% (24/31), 4d 52% (13/25), and combined (4n, 4m, 4l, 4r, 4o) 62.5% (5/8) ( P = 0.046).

CONCLUSION

No obvious cause for the mode of HCV transmission was noted in majority of the patients. No significant correlation was observed between HCV-4 subtypes and the source of HCV infection. 4a and 4d subtypes were the most common in Saudi Arabia, and patients infected with 4a subtype responded significantly better to combination therapy than to 4d subtype.

Evaluated outcomes in patients with Chronic Hepatitis C

AIM

The objective of this study was to evaluate the real outcomes of chronic hepatitis C patients, who treated with interferon plus ribavirin (INF-RBV) and peg-interferon plus ribavirin (PEG-RBV).

BACKGROUND

Despite the PEG-RBV has become a standard treatment of hepatitis C virus (HCV) around the world; and in Iran too, but in developing countries like as Iran, INF-RBV is still used among some patients for treating HCV, due to the high costs of treatment with PEG-RBV.

PATIENTS AND METHODS

The present cross-sectional study was conducted on 77 naïve patients referred to a private gastroenterology clinic between years 2007 through 2009 in Tehran. Patients had participated in this study taking two types of combination therapies, based on standard protocol of the Iranian Ministry of Health. At the end of the treatment, sustain virological response (SVR) rate was evaluated.

RESULTS

The outcomes showed in INF-RBV treatment; 11.6%, 16.3% and 34.9% patients were suffered from relapse, lost follow-up their treatment and non-responder, respectively, and finally 37.2% of the patients reached SVR. In PEG-RBV treatment outcomes were as follows; 2.9%, 14.7% and 14.7% patients were non-responder, lost follow-up their treatment and suffered from a relapse, respectively, and 67.6% of the patients reached SVR. The multivariate-adjusted odds ratios of outcomes showed that treated with PEG-RIB and also genotype 3a than the others genotypes in this treated had more chance to achieved SVR.

CONCLUSION

The findings of the present study showed that the rate of SVR in patients who treated with PEG-RBV significantly was higher than patients who treated with INF-RBV. Also in PEG-RBV the chance of achieving SVR is higher among the patients with genotype 3a than among those with other genotypes.

Non-invasive prediction of hepatic fibrosis in patients with chronic HCV based on the routine pre-treatment workup

BACKGROUND

Hepatic fibrosis is an inclusion indicator for treatment and a major independent predictor of treatment response in patients with chronic hepatitis C. Liver biopsy, considered as the "gold standard" for evaluating liver fibrosis, has carried some drawbacks. Currently used noninvasive predictors of fibrosis are considered less accurate than liver biopsy.

OBJECTIVES

Our aim was to assess noninvasive predictors of fibrosis in patients with chronic hepatitis C using the routine laboratory pre-treatment workup.

PATIENTS AND METHODS

Cross sectional study including 4289 Egyptian patients with chronic hepatitis C were assessed for the need to interferon and ribavirin therapy. Routine pre-treatment workup and reference needle liver biopsy were performed. FIB-4 index, APRI and modified APRI scores were validated. Patients were divided into two groups, first with no or minimal fibrosis, and second with moderate and marked fibrosis using the Metavir score.

RESULTS

Multivariate logistic regression analysis showed that age, body mass index, aspartate aminotransferase, alpha fetoprotein, platelets count, FIB-4 index, APRI and modified APRI score were significant independent predictors of fibrosis. Age > 43 years, aspartate aminotransferase > 47U/L, platelets < 205×103/mm(3), and alpha fetoprotein > 2.6 ng/ml had the highest cutoff points in receiver operator characteristic curves. Taking into account the four variables together; the presence of ≥ 2 variables is associated with moderate and advanced fibrosis with a sensitivity of 0.81, specificity of 0.5, positive predictive value of 0.53 and negative predictive value of 0.79. FIB-4 index represented the best performing receiver operator characteristic curve for diagnosing moderate and marked fibrosis among other independent factors with a sensitivity of 0.74, specificity of 0.6, positive predictive value of 0.56 and negative predictive value of 0.76.

CONCLUSIONS

Chronic HCV pre-treatment routine work up and composite fibrosis scores are good noninvasive predictor of liver fibrosis and can be used as an alternative method to invasive liver biopsy without adding more financial expenses to the treatment.

Real response to therapy in chronic hepatitis C virus patients: a study from iran

BACKGROUND

Despite significant advances in the treatment of chronic hepatitis C in the past decades, factors which can affect response rates to combination therapy; peginterferon and ribavirin, are still under study and reaching sustained virological response (SVR) is affected by several different factors.

OBJECTIVES

To investigate predictor factors contributing to SVR in Iranian patients.

PATIENTS AND METHODS

The present non-randomized, clinical trial was conducted on 100 patients referred to the Tehran Hepatitis Center in 2009-2011. The patients were administered combined peginterferon α-2a-ribavirin treatment, based on the standard protocol of the Iranian Ministry of Health. At the end of the treatment, the SVR rate and predictors were evaluated.

RESULTS

The mean age of the patients was 42 and 78% were male. Genotype 1a was the most common (70%) and 55% of patients were treatment naïve. The outcomes showed that 12%, 16% and 22% patients were; non-responders, breakthroughs and relapsers, respectively, while 50% of the patients reached SVR. Patients reaching SVR were aged 40 years or lower, they were less likely to have been a non-responder in prior treatments, more likely to have a non-1a genotype and a higher number had an HCV RNA of less than 600 000 IU/ml. The multivariate analysis showed that an age of 40 or lower (OR = 3.74, CI95% = 1.52-9.22), a non-1a genotype (OR = 3.71, CI 95% = 1.40-9.81) and an HCV RNA less than 600 000 IU/ml (OR = 2.52, CI 95% = 1.03-6.15) may be useful SVR predictors.

CONCLUSIONS

The findings of the present study showed that half of the patients reached SVR through combined peginterferon α-2a and ribavirin treatment, the majority of whom had genotype 3a and a minority had genotype 1a. In addition, an age of 40 or lower, non-1a genotype and a viral load less than 600 000 IU/ml were strong SVR predictors.

Low dose ribavirin for treatment of hepatitis C virus infected thalassemia major patients; new indications for combination therapy

BACKGROUND

Treatment guidelines contraindicate ribavirin for treatment of hepatitis C virus (HCV) infection in thalassemia major patients. Nevertheless, the current evidence suggests that ribavirin might be tolerated by these patients.

OBJECTIVES

Despite this evidence, low dose ribavirin combination therapy has not been compared with peginterferon monotherapy in these patients so far.

PATIENTS AND METHODS

Two hundred eighty thalassemia patients with detectable HCV-RNA PCR (≥ 50 IU/mL) and liver histology consistent with chronic HCV infection were self-assigned to receive peginterferon alfa-2a (n = 81) monotherapy or its combination therapy with ribavirin, 600-800 mg QD, according to hemoglobin levels (n = 199). Treatment experienced patients were eligible for this study.

RESULTS

Sustained virological response (SVR) was significantly higher in patients who received ribavirin (51 % vs. 38 % P = 0.02). In multivariate regression, OR of ribavirin for prediction of SVR was 2.2 (95 % CI 1.24-3.91). The SVR was significantly higher in the ribavirin group in subgroups of patients with more than 24 years of age, elevated ALT, ferritin < 2006 ng/mL, previous treatment failure, genotype 1, positive history of splenectomy, fibrosis score of 0-4 HAI and viral load < 600,000 IU/mL. Treatment discontinuations due to the safety concerns were comparable between the treatment groups (6.5 and 8 %). Furthermore, transfusion intervals were almost halved in patients who received low dose ribavirin.

CONCLUSIONS

According to the present study, adult thalassemia patients with HCV infection can be treated successfully with low dose ribavirin. Hence, we strongly advise combination therapy in thalassemia patients with aforementioned clinical characteristics. Moreover, ribavirin does not seem to be beneficial in thalassemia patients below 18 years of age.

Insulin resistance, steatosis, and fibrosis in Egyptian patients with chronic Hepatitis C virus infection

BACKGROUND/AIM

Both nonalcoholic fatty liver disease (NAFLD) and chronic hepatitis C virus (HCV) infection are common in Egypt, and their coexistence is expected. There is controversy regarding the influence of NAFLD on chronic HCV disease progression. This study evaluates the effect of NAFLD on the severity of chronic hepatitis C (CHC) (necroinflammation and fibrosis) and assesses the relative contribution of insulin resistance syndrome to the occurrence of NAFLD in patients with chronic HCV infection.

PATIENTS AND METHODS

Untreated consecutive adults with chronic HCV infection admitted for liver biopsy were included in this study. Before liver biopsy, a questionnaire for risk factors was completed prospectively, and a blood sample was obtained for laboratory analysis.

RESULTS

Our study included 92 male patients. Their mean ± SD age and aspartate aminotransferase (AST) level were 42 ± 7.7 years (range 20-56) and 68 ± 41.7 U/L (range 16-214), respectively. The mean insulin level and insulin resistance index were 15.6 ± 18.3 mIU/mL (range 5.1-137.4) and 5.9 ± 15.2 (range 0.9-136.2), respectively. Fifty four percent of patients had steatosis and 65% had fibrosis. In multivariate analyses, steatosis was associated with insulin resistance and fibrosis was associated with high AST level, age ≥40 years, and steatosis.

CONCLUSIONS

Steatosis is a histopathologic feature in >50% of patients with chronic HCV infection. Insulin resistance has an important role in the pathogenesis of steatosis, which represents a significant determinant of fibrosis together with high serum AST level and older age.

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Peginterferon alpha-2a and ribavirin treatment of patients with haemophilia and hepatitis C virus infection: a single-centre study of 367 cases

BACKGROUND/AIMS

Chronic hepatitis C virus infection (HCV) is a major comorbidity in patients with haemophilia. Peginterferon alpha and ribavirin is current standard anti-HCV therapy but there is little information about safety and efficacy of peginterferon alpha-2a and ribavirin combination therapy in these patients.

MATERIAL AND METHODS

In an open-label single-treatment arm cohort study, 367 haemophilia patients seronegative for hepatitis B and human immunodeficiency virus markers and chronically infected with HCV (HCV RNA>50 IU/ml for at least 6 months) received 180 microg of Pegasys and 800-1200 mg of ribavirin according to body weight. Genotypes 1 and 4, mixed and untypable infections were treated for 48 weeks, while genotypes 2 and 3 were treated for 24 weeks. The efficacy of therapy was expressed as sustained virological response (SVR).

RESULTS

Two hundred and twenty-five subjects [61%, 95% confidence interval (CI) 56-66] achieved SVR, 66 patients relapsed and 30 subjects did not respond and nine patients developed breakthrough during treatment. In a multivariate logistic regression model, age<24 odds ratio (OR)=1.8 (95% CI 1.1-3.1), genotype non-1 OR=1.8 (95% CI 1.1-3.2), BMI<25 OR=2.1 (95% CI 1.3-3.3) and HCV RNA<600 000 IU/ml OR=1.7 (95% CI 1.1-3.2) were independent predictors of SVR. Eight patients discontinued the treatment because of persistent neutropaenia and 22 subjects were dropped out because of intractable side effects. Furthermore, two patients died during treatment and five were lost to follow-up after treatment cessation.

CONCLUSIONS

Peginterferon alpha-2a in combination with weight-based ribavirin has SVR rate of 51% for genotype 1 and 71% for genotype non-1 infections in haemophilia patients. Age<24, BMI<25, viral load<600 000 IU/ml and genotype non-1 are the major determinants of SVR achievement in these patients.

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.

Silibinin and related compounds are direct inhibitors of hepatitis C virus RNA-dependent RNA polymerase

BACKGROUND & AIMS

Silymarin is a mixture of flavonolignans extracted from the milk thistle. Silymarin contains several molecules, including silibinin A, silibinin B, isosilibinin A, isosilibinin B, silicristin, and silidianin. Intravenous infusion of silibinin induces dose-dependent reduction of hepatitis C virus (HCV) RNA levels. The aim of this study was to test the principal isomers contained in silymarin preparations for their ability to inhibit HCV enzymatic functions and replication in different models.

METHODS

The inhibitory activity of silymarin components was tested in HCV RNA-dependent RNA polymerase and NS3/4A protease enzyme assays. Their ability to inhibit replication of an HCV genotype 1b replicon model and the JFH1 infectious HCV model in cell culture was also studied.

RESULTS

Silibinin A, silibinin B, their water-soluble dihydrogen succinate forms and Legalon SIL, a commercially available intravenous preparation of silibinin, inhibited HCV RNA-dependent RNA polymerase function, with inhibitory concentrations 50% of the order of 75-100 microM. Silibinin A and silibinin B also inhibited HCV genotype 1b replicon replication and HCV genotype 2a strain JFH1 replication in cell culture. None of these compounds inhibited HCV protease function.

CONCLUSIONS

Silibinin A and silibinin B, as well as Legalon SIL, inhibit HCV replicon and JFH1 replication in cell culture. This effect is at least partly explained by the ability of these compounds to inhibit HCV RNA-dependent RNA polymerase activity. Our results provide a basis for the optimization and subsequent development of members of the Flavonoid family as specific HCV antivirals.