Effects of host and virus related factors on interferon-α+ribavirin and pegylated-interferon+ribavirin treatment outcomes in chronic Hepatitis C patients

Sequence variability of HCV 3a isolates based on core gene in patients from Lahore, Pakistan

Aim: To investigate the HCV 3a core sequence variation and amino acid substitutions of patients from Lahore, Pakistan. Materials & methods: Blood samples from HCV positive patients (n = 232) were collected for viral genotypes. Moreover, the nucleotide sequencing was performed for core gene of 20 samples. Results: Viral genotyping showed that 69.82% (n = 162) belonged to 3a genotype, 9.05% (1a; n = 21), 2.15% (3b; n = 5) and 18.98% were untypable (n = 44). Phylogenetic analyses suggest majority of our isolates clustered with previously reported reference isolates from Pakistan. The remaining isolates clustered with HCV-core sequences reported from Vietnam, Japan, Thailand, Iran, USA, Bangladesh, Malaysia and Morocco. Conclusion: We report HCV-core substitutions (G60E, R70Q, C91A, A94Q and Q63E/D) that could be associated with treatment response in Pakistani patients.

A case of a patient infected with a hepatitis C virus genotype 3a multidrug resistant variant in Pakistan

BACKGROUND

Approximately 10 million people in Pakistan are infected with the hepatitis C virus (HCV). Most patients develop chronic hepatitis, with rare cases of spontaneous clearance. However, little is known about multidrug resistant viral variants in Pakistan.

FINDINGS

This case study describes a 47-year-old male diagnosed with chronic HCV genotype 3a infection in 2003. After an initial diagnosis of viral infection, the patient remained treatment naïve for 5 years. He received two therapy cycles of interferon (IFN) plus ribavirin (RBV) in 2007 and 2010, however, he was non-responsive to the therapy. The patient then received an additional two treatment cycles of pegylated IFN α-2b plus RBV (in 2011 and 2013); he was still non-responsive. In 2016, the patient underwent sofosbuvir plus RBV combination therapy, however, the sustained virological response was still not achieved. The host genetic factor was found to be heterozygous guanine and thymine (GT) and cytosine and thymine (CT) genotypes of rs8099917 and rs12979860 polymorphism of IL28B, respectively. Phylogenetic analysis suggests that the resistant variant belong to an out-group and may require triple therapy.

CONCLUSIONS

This is the first case that reports on a HCV-infected individual who was a non-responder to multiple IFN therapies in Pakistan. Further studies are needed to understand multidrug-resistant HCV variants in the Pakistani population.

A systematic review of treatment response rates in Pakistani hepatitis C virus patients; current prospects and future challenges

BACKGROUND

The estimated hepatitis C virus (HCV) carriers are approximately 10 million in Pakistan which usually progresses to chronic hepatitis, with rare cases of spontaneous viral eradication. The present article reviews the treatment status of HCV infection in Pakistani population and various factors associated with the treatment response rates.

METHODS

Literature on anti-HCV therapy was searched in PubMed, Google Scholar and PakMediNet. Thirty three different studies representing different geographic regions of Pakistan published from 2002 to 2016 were included in the present review. Weighted mean, standard error estimates (SE) and standard deviation (SD) were determined for each population group.

RESULTS

Mean value for sustained virological response (SVR) for standard IFN plus ribavirin (RBV) combination therapy was 68.38% ± 14.13% (range 33.8%-87.10%; SE 3.08) and pegylated-IFN plus RBV combination therapy 64.38% ± 8.68% (range 55.0%-76.00%; SE 3.88). The lowest value for SVR has been reported to be 24.3% (for genotype 1; administering INF-α 2b 3MU 3 times/week and RBV 1000-1200 mg/day for 48 weeks) while highest of 87.5% (genotype 3a; INF-α 2a 3MU 3 times/week and RBV 1000-1200 mg/day for 24 weeks). The mean value for rapid virological response (RVR) was found to be 48.18% ± 29.20% (SE 9.73). As PEG-interferon and direct acting antivirals (DAAs) are relatively expensive, interferon-alfa (IFN-α) and RBV combination therapy have been used widely to treat HCV infected patients in Pakistan for the last one and half decade. On average, 2.45% of the patients discontinued treatment due to severe side effects.

CONCLUSION

We encourage further studies on understanding host and viral factors associated with specific focus on harder to treat viral variants (relapsers and nonresponders). These variants are currently rising in the country.

Effect of Gender on the Response to Hepatitis C Treatment in an Inner-City Population

INTRODUCTION

Hepatitis C virus (HCV) is the leading cause of cirrhosis, hepatocellular carcinoma, and liver transplantation in the United States. Response to treatment has improved with the addition of direct acting protease inhibitors. However, there are limited real-world data on the role of gender in achieving a sustained virologic response (SVR).

METHODS

We conducted a cross-sectional study in 70 patients treated for HCV, genotype 1 infection with pegylated alpha interferon, ribavirin, and either telaprevir or boceprevir at our inner-city liver clinic.

RESULTS

The SVR was significantly lower in women than in men (24% vs. 59%; p < .01). Statistical significance persisted after adjusting for age, race, genotype, prior treatment status, duration of therapy, and stage of fibrosis. The adjusted odds ratio for achieving SVR was significantly lower in women than in men (odds ratio [OR], 0.13; 95% CI, 0.03-0.58; p = .01). Relapse after completing treatment was more likely to occur in women (p = .02). Thirty-four patients (48%) did not complete therapy. Discontinuation because of loss to follow-up was more likely in women, whereas discontinuation owing to therapy limiting adverse drug events were more common in men. Discontinuation rates owing to failure of therapy were similar in men and women.

CONCLUSIONS

There was a significant difference in SVR between men and women. Both biological and nonbiological factors, the latter including access to care, adherence to therapy, and attitudes of and toward health care providers all could play a role in contributing to the observed disparity between sexes in treatment response.

The influence of host factors and sequence variability of the p7 region on the response to pegylated interferon/ribavirin therapy for chronic hepatitis C genotype 1b in patients from Serbia

The goal of this study was to identify host and viral factors affecting the response to pegylated interferon/ribavirin (PEG-IFN/RBV) treatment in patients with chronic hepatitis C genotype 1b. Baseline characteristics of the patients and sequences within the p7 region were analyzed in pre-treatment serum samples from 53 individuals with chronic hepatitis C genotype 1b and related to the outcome of therapy. We found a significant correlation between age and response to therapy (p < 0.001). Furthermore, the pre-treatment viral load was closely associated with the stage of liver fibrosis (p < 0.001). The presence of fewer than 4 mutations and age above 40 were significantly associated with non-response (NR) (p < 0.001). Our findings may be useful for estimating the likelihood of achieving a sustained virologic response (SVR) in patients who are chronically infected with hepatitis C virus genotype 1b.

The genotype CC of IL-28B SNP rs12979860 is significantly associated with a sustained virological response in chronic HCV-infected Pakistani patients

OBJECTIVE

To evaluate the association of genetic variation in interleukin 28B (IL-28B) gene and viral factors with treatment outcome in chronic hepatitis C virus (HCV)-infected patients in Pakistan.

METHODS

Patients with chronic HCV infection who received interferon plus ribavirin combination therapy were enrolled in the study. The viral loads were checked at the third and sixth month of treatment and 6 months after the completion of the treatment. Genotyping of single-nucleotide polymorphism (SNP) rs12979860 of IL-28B gene was performed by the restriction fragment length polymorphism method and direct sequence analysis.

RESULTS

A total of 111 patients successfully completed antiviral therapy and the follow-up period. Early virological response (EVR) and a sustained virological response (SVR) were achieved in 92 and 91 patients, respectively. Patients infected with HCV genotype 3a had a higher SVR rate compared with other HCV genotypes. A higher C allele frequency (81.9%) was observed in patients with SVR than those with non-SVR (P = 0.00001). The odds ratio of achieving SVR was more than 10-fold greater for the CC genotype than the CT/TT genotypes of SNP rs12979860 (OR 10.351, 95% CI 1.925-55.653, P = 0.006). Other positive predictors observed for SVR were female gender and EVR.

CONCLUSION

The CC genotype of IL-28B SNP rs12979860 is an independent predictive factor for SVR in chronic HCV-infected patients in Pakistan.

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.

Effect of interferon plus ribavirin therapy on hepatitis C virus genotype 3 patients from Pakistan: Treatment response, side effects and future prospective

More than 10 million people are suffering from hepatitis C virus (HCV) in Pakistan. The available treatment option is a combination of interferon and ribavirin. Treatment response is linked with several factors and also induces a number of side effects. We searched in Pubmed, Pak Medi Net and Google Scholar for the articles presenting the effect of interferon plus ribavirin therapy on HCV patients from Pakistan, their side effects and future prospects. The major prevalent HCV genotype in Pakistan is 3. Conventional interferon alpha plus ribavirin showed sustained virological response of 54%-64% while pegylated interferon alpha plus ribavirin showed sustained virological response of 58%-75%. IL-28B CC genotype is linked with better sustained virological response. Studies on patients with HCV genotype 3 infections showed no correlation between treatment response and interferon sensitivity determining region mutations. Interferon therapy is linked with a number of side effects like thyroid dysfuncton, haematological disorders, weight loss, gastrointestinal tract side effects and neuropsychiatric side effects. Unusual side effects of clubbing of fingers and seizures were also observed in a couple of patients. Interferon alpha plus ribavirin therapy showed better response rate in HCV genotype 3 patients from Pakistan with number of side effects. A couple of interferon free therapies are light of hope for the patients living with HCV.

Sex hormones and HCV: an unresolved mystery

The biological differences between males and females advocate the ultimate need for gender-specific medicine. The variation in response to viral infection as well as therapy among different genders makes it very intriguing to reveal the responsible factors for causing this discrepancy. HCV is one of the most noxious infectious diseases, however the impact of gender on the response to HCV has received negligible attention in the literature. The controversial studies concerning the effect of gender on the outcome of interferon-based therapy urge a need to judge the gender discrepancy in host factors responsible for both interferon release and action. The main aim of this review is to disentangle the interplay between sex hormones and several viral and host factors responsible for viral clearance in an attempt to clarify the role of gender in modulating the response to HCV as well as interferon-based therapy.

Analysis of variables and interactions among variables associated with a sustained virological response to pegylated interferon alfa-2a plus ribavirin in hepatitis C virus genotype 3-infected patients

BACKGROUND

The recommended standard therapeutic regimen for chronic hepatitis patients with hepatitis C virus (HCV) genotype 3 is pegylated interferon plus ribavirin for 24 weeks. The aim of the present study was to evaluate treatment efficacy and variables predictive of treatment success, interactions among variables contributing to a response to therapy, and the utility of the rapid virological response (RVR; week 4 virological response) to predict treatment outcomes in HCV genotype 3-infected patients in routine clinical practice.

METHODS

We prospectively studied baseline and during-treatment factors associated with a sustained virological response (SVR) in HCV genotype 3-infected patients who received pegylated interferon alfa-2a (PEG-IFN α2a) 180 μg/week plus ribavirin 800 mg daily for 24 weeks and who were followed for 24 weeks after the completion of treatment.

RESULTS

Four hundred and twenty-six treated patients were included in the analysis; 320 (75.1%) showed an SVR. The following factors were assessed for their ability to predict SVR by means of univariable and multivariable logistic regression analysis: patient age, sex, pre-treatment viral load, pre-treatment alanine aminotransferase (ALT), body mass index (BMI), and RVR. Four factors - age, pre-treatment viral load, pre-treatment ALT, and RVR - were statistically significant predictors of SVR (p<0.05) in the univariable analysis. Factors showing a significant association with SVR were assessed by multivariable logistic regression analysis. In the multivariable analysis, independent factors associated with SVR were the attainment of RVR (odds ratio (OR) 11, 95% confidence interval (CI) 6.15-20.69; p<0.0001), patient age ≤40 years (OR 4.2, 95% CI 2.30-7.96, p<0.0001), and a low pre-treatment viral load (≤8 × 10(5) IU/ml; OR 3.4, 95% CI 1.87-6.25; p<0.0001). The effect of RVR in patients aged >40 years was more pronounced than in those aged ≤40 years: 81.1% of patients aged >40 years who achieved an RVR had an SVR, whereas only 7.5% of patients aged >40 years who did not achieve an RVR had an SVR (p<0.05).

CONCLUSIONS

RVR is an independent variable that is predictive of SVR. Moreover older patients (>40 years) who achieve an RVR are likely to have an SVR, while patients who do not achieve an RVR and who have a high pre-treatment viral load (>8 × 10(5) IU/ml) are unlikely to have an SVR.

Prediction of response to pegylated-interferon-α and ribavirin therapy in Chinese patients infected with different hepatitis C virus genotype

BACKGROUND

The standard treatment for patients with chronic hepatitis C (CHC), pegylated interferon-α (PEG-IFN) plus ribavirin (RBV) does not provide a sustained virological response (SVR) in all patients. Genetic variations at the interleukin 28B (IL-28B) locus are important in predicting outcome following therapy in CHC patients.

RESULTS

We investigated the role of IL28B variations (rs8099917) in response to PEG-IFN-α/RBV treatment and evaluated its association with the risk of the null virological response (NVR) and relapse (REL) in different viral genotypes. We found that the overall distributions of the genotype among the SVR, NVR, and REL groups were significantly different (P < 0.001). Patients with the TG genotype had an increased risk of NVR and REL (OR = 6.45 95% CI = 2.88-14.47, P < 0.001 for NVR; OR = 2.51, 95% CI = 1.29-4.86, P = 0.006 for REL, respectively), and patients with the GG genotype had a further increased risk of NVR and REL (OR = 12.04, 95% CI = 3.21-45.13, P < 0.001 for NVR; ,OR = 4.30, 95% CI = 1.21-15.13, P = 0.017 for REL, respectively). G variant genotypes (TG+GG) also had an increased risk of NVR and REL, and there was a significant trend for a dose-effect of G allele on the risk of NVR and REL (P < 0.05). The SVR rate in TT higher than in TG+GG was more pronounced in those patients infected with non-G1 compared to the patients infected with G1. The treatment response did differ based on the rs8099917 genotype in patients with different viral genotypes, compared with patients infected with the non-G1, the G1 infected patients had an increased risk of NVR and REL (OR = 2.03 95% CI = 1.03-4.01, P = 0.04 for NVR and OR = 2.58, 95% CI = 1.35-4.94, P = 0.004 for REL, respectively). Moreover, multivariate regression analysis show that the rs8099917 G allele was the only independent factor significantly associated with a NVR and REL.

CONCLUSION

This study suggests that host genetic polymorphisms rs8099917 in the vicinity of IL-28B is the most important predictor of treatment response of PEG-IFN-α/RBV for HCV patients in China.

Chronic hepatitis C treatment outcomes in low- and middle-income countries: a systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness of treatment for hepatitis C virus (HCV) infection in low- and middle-income countries and identify factors associated with successful outcomes.

METHODS

We performed a systematic review and meta-analysis of studies of HCV treatment programmes in low- and middle-income countries. The primary outcome was a sustained virological response (SVR). Factors associated with treatment outcomes were identified by random-effects meta-regression analysis.

FINDINGS

The analysis involved data on 12 213 patients included in 93 studies from 17 countries. The overall SVR rate was 52% (95% confidence interval, CI: 48-56). For studies in which patients were predominantly infected with genotype 1 or 4 HCV, the pooled SVR rate was 49% (95% CI: 43-55). This was significantly lower than the rate of 59% (95% CI: 54-64) found in studies in which patients were predominantly infected with other genotypes (P = 0.012). Factors associated with successful outcomes included treatment with pegylated interferon and ribavirin, infection with an HCV genotype other than genotype 1 or 4 and the absence of liver damage or human immunodeficiency virus infection at baseline. No significant difference in the SVR rate was observed between weight-adjusted and fixed-dose ribavirin treatment. Overall, 17% (95% CI: 13-23) of adverse events resulted in treatment interruption or dose modification, but only 4% (95% CI: 3-5) resulted in treatment discontinuation.

CONCLUSION

The outcomes of treatment for HCV infection in low- and middle-income countries were similar to those reported in high-income countries.