The role of ribavirin in direct acting antiviral drug regimens for chronic hepatitis C

Therapeutic effect of intravenous acyclovir in children with infectious mononucleosis and immune function

OBJECTIVE

To explore the application value of intravenous acyclovir in children with infectious mononucleosis (IM) and its effects on immune function.

METHODS

The data of 136 children with IM treated in Anhui Provincial Children's Hospital from March 2019 to March 2022 were retrospectively analyzed. According to the inclusion and exclusion criteria, 98 children were selected. Among them, 45 children treated with routine ribavirin were assigned to the control group, and the other 53 children treated with intravenous acyclovir were enrolled into the observation group. The two groups were compared in terms of efficacy, incidence of adverse reactions, recovery time of clinical symptoms, and immune function indexes, IgG, IgA, IgM, white blood cell (WBC) count and lymphocyte proportion, before and 10 days after the treatment. Independent risk factors affecting efficacy were analyzed by multivariate logistic regression analysis.

RESULTS

The observation group showed a significantly higher overall response rate than the control group (P=0.025). The control group experienced significantly longer recovery time of body temperature returning to normal, cure time of isthmitis, time for lymph node reduction, and alleviation time of hepatomegaly than the observation group (P<0.05). Additionally, the control group presented with a significantly higher incidence of adverse reactions than the observation group (P=0.028). After treatment, the observation group showed significantly lower levels of IgG, IgA, IgM, WBC count and lymphocyte proportion than the control group (all P<0.010). Longer average course of disease (OR: 1.449, 95% CI: 1.095-1.918), higher admission temperature (OR: 6.996, 95% CI: 1.350-36.257), higher admission IgA level (OR: 4.735, 95% CI: 1.357-16.520) and higher admission IgG level (OR: 1.470, 95% CI: 1.012-2.134) were independent risk factors for ineffective efficacy, while acyclovir (OR: 0.058, 95% CI: 0.005-0.729) was an independent protective factor.

CONCLUSION

In the treatment of IM, intravenous acyclovir can substantially improve the overall clinical response rate for patients, with less adverse reactions, and can greatly alleviate various clinical symptoms and signs including fever, isthmitis, cervical lymph node enlargement, and hepatosplenomegaly, with obvious regulating effects on the immune function, so it is worth popularizing and applying in clinical practice.

Identification of ribavirin-responsive cis-elements for GPAM suppression in the GPAM genome

Glycerol-3-phosphate acyltransferase, mitochondrial (GPAM) is a rate-limiting enzyme catalyzing triglyceride synthesis. Recently, we demonstrated that the anti-viral drug ribavirin (RBV) reduces GPAM expression by downregulating CCAAT/enhancer-binding protein α (C/EBPα). However, the precise mechanisms of GPAM suppression have remained unclear. Here, we found that RBV suppressed GPAM expression by downregulating not only C/EBPα, but also sterol regulatory element-binding protein-1c (SREBP-1c). We also found that cis-elements regulated by C/EBPα and SREBP-1c functioned as distal and proximal enhancers, respectively, to express hepatocyte- and adipocytes-specific GPAM variants. These results imply that RBV disrupts formation of the enhancer machineries on the GPAM genome by downregulating both transcription factors. Our findings may contribute to the development of treatments for fatty liver diseases caused by aberrant triglyceride synthesis.

Decrease in Chitinase 3-Like Protein 1 Levels Reflects Improvement in Liver Fibrosis after HCV Eradication

Aim

The success of direct-acting antivirals (DAAs) against hepatitis C virus is a major breakthrough in hepatology. Previous studies have shown that chitinase 3-like protein 1 (CHI3L1) was a marker for staging of liver fibrosis caused by HCV. In this investigation, we used CHI3L1 as a surrogate marker to compare dynamic hepatic fibrosis variations following the elimination of HCV among cases receiving sofosbuvir (SOF)-based regimens and pegylated interferon/ribavirin (PR) treatments.

Methods

The study enrolled 105 patients, including 46 SOF-based regimens treated patients, 34 PR-experienced patients, and 25 untreated patients. Serum samples and clinical data were obtained at the baseline, the end of treatment, and at weeks 24 and 48 after treatments.

Results

First, we found that serum level of CHI3L1 correlated moderately but significantly with LSM (r = 0.615, P < 0.001) at the baseline, and diagnosed liver cirrhosis at baseline with high accuracy (AUC = 0.939) by ROC analysis. So we explored CHI3L1 as a sensitive biomarker to monitor the regression of liver fibrosis after HCV eradication. We found that the serum CHI3L1 level of CHC cases receiving SOF-based regimen treatments was markedly reduced immediately after treatment compared with that at the baseline (123.79 (118.55) vs. 118.20 (103.68), P = 0.001). For cases undergoing PR treatment, the serum CHI3L1 decreased significantly at week 24 posttreatment compared with that at the baseline (69.98 (51.44) vs 89.15 (110.59), P = 0.016). For the untreated cirrhotic patients, CHI3L1 levels increased at week 96 follow-up compared with that at the baseline (194.73 (172.46) vs. 89.50 (242.97), P = 0.048), reflecting continued worsening of liver fibrosis.

Conclusion

CHI3L1 is suggested to be the sensitive marker to monitor fibrosis variations in weeks during treatments and after achieving SVR. It has the potential to allow the identification of early treatment failure for a timely switch to alternative treatment and to allow monitoring progression of fibrosis as a risk factor for liver cirrhosis.

Association between hepatitis C antiviral treatment and diabetes mellitus: A case series

The hepatitis C virus (HCV) infects 185 million people worldwide, and diabetes mellitus (DM) affects 415 million. There has long been a possible association between DM and liver outcomes for patients with HCV infection. We present two cases of worsening glucose resistance and one case of emergent type 1 DM after completion of HCV. The complex interactions between HCV infection and both type 1 and type 2 DM have not yet been elucidated. In addition, consequences and side effects of treatment options for HCV have not been fully studied in the diabetic population. Our case series illustrates a potential complication of HCV treatment, which may warrant additional consideration prior to initiation of therapy as well as monitoring and surveillance post-cure.

Dynamic changes in innate immune responses during direct-acting antiviral therapy for HCV infection

The role of the endogenous interferon (IFN) system has been well characterized during IFN-based therapy for chronic hepatitis C virus (HCV) infection; less is known for direct-acting antivirals (DAAs). In this phase 3b open-label study, we assessed changes in IFN-stimulated genes (ISGs) in non-cirrhotic treatment-naïve or pegIFN/RBV-experienced HCV-GT1a-infected patients receiving paritaprevir/ritonavir/ombitasvir + dasabuvir + ribavirin (PrOD + R) for 12 weeks. ISG expression was quantified from peripheral blood mononuclear cells at baseline, treatment weeks (TW)2, TW4, TW8, end of treatment (EOT) and at post-treatment week 12. Paired sera were used to assess IFN-α/IFN-related chemokines/cytokines. Twenty-five patients were enrolled. Overall sustained virologic response (SVR)12 was 92% (no virologic failure [VF]) and 100% for those completing the study protocol. Two patients were excluded from the ISG analysis due to lack of post-treatment samples. The majority of ISGs were downregulated at TW2-TW4 (nadir TW4); however, a relative increase was observed at TW8-EOT, although levels were lower than baseline. This downregulation was accompanied by increases in IFN-α/IFN-related chemokines, a finding not observed with T_H 1/2-related cytokines. Following SVR, ISG expression returned to TW2 levels. In conclusion, PrOD + R for 12 weeks was well-tolerated with no VF. Our data demonstrate dynamic alterations in innate immune profiles during highly potent IFN-free DAA therapy. The downregulation of ISG post-therapy suggests reversal of the "exhausted" ISG phenotype following SVR, and the rise in ISGs and IFN-α/IFN-responsive chemokines late during therapy suggests resetting of IFN responsiveness that may be relevant in determining duration of or immunological sequelae from DAA therapy, including HBV reactivation.

Safety and efficacy of sofosbuvir and ribavirin for genotype 2 hepatitis C Japanese patients with renal dysfunction

AIM

The safety and efficacy of sofosbuvir (SOF) and ribavirin (RBV) have not been well clarified in patients with renal dysfunction because clinical trials have not included such patients. We evaluated the safety and efficacy of SOF and RBV for genotype 2 hepatitis C virus (HCV)-infected patients with renal dysfunction.

METHODS

The study included genotype 2 HCV-infected patients who received SOF and RBV between July 2014 and May 2017. The sustained virologic response (SVR) after the treatment and safety during the therapy were evaluated according to renal function.

RESULTS

A total of 231 patients were included in this study. The median age was 62 years old, and 45.9% (106/231) were men. Of the 231 patients, 191 (82.8%) and 40 (17.2%) were classified as having chronic kidney disease (CKD) stages G1/2 and G3, respectively. The overall SVR rate was 97% (224/231). The SVR rates in patients with CKD stages G1, 2, G3a, and G3b were 98.1%, 98.6%, 87.9%, and 100%, respectively, and this therapy was tolerated. Multivariate analysis indicated that renal dysfunction was significantly associated with a non-SVR (odds ratio, 6.963; 95% confidence interval, 1.494-32.41; P = 0.013). The patients with renal dysfunction were older, had advanced liver fibrosis, lower baseline platelet and hemoglobin levels, and a higher rate of RBV dose reduction.

CONCLUSIONS

Sofosbuvir and RBV therapy is highly effective and safe for genotype 2 HCV-infected Japanese patients. However, attention should be paid to baseline renal function when SOF- and RBV-containing regimens are used for patients with renal dysfunction.

Interferon-free direct-acting antiviral therapy for acute hepatitis C virus infection in HIV-infected individuals: A literature review

Dramatic rises in hepatitis C virus (HCV) coinfection rates in human immunodeficiency virus (HIV)-infected individuals have been observed recently, largely attributable to increasing recreational drug use combined with increased testing for HCV. In the era of direct-acting antiviral (DAA) therapy, treatment of acute HCV infection in HIV-infected individuals with short durations of these drugs may potentially reduce the disease and economic burden associated with HCV infection as well as reducing the likelihood of onward HCV transmission. We performed an extensive literature search of PubMed, Embase and Google Scholar up to 05 September 2017 for clinical trials of acute HCV infection in HIV-infected individuals. In the studies identified, rates of sustained virologic response at 12 weeks post-treatment (SVR12) ranged from 21% with 6 weeks of therapy up to 92% with 12 weeks of therapy with sofosbuvir and ribavirin. Ledipasvir/sofosbuvir for 6 weeks achieved an SVR of 77%. No HIV-related events occurred regardless of whether patients were receiving antiretroviral therapy (ART) and DAAs were well tolerated. Data is currently limited with regards to optimal regimens and durations of therapy, which need to be tailored based on potential interactions with concurrent ART and consideration for the fact that patients with higher baseline HCV RNA levels may require an extended duration of treatment.

Efficacy and safety of sofosbuvir plus simeprevir therapy in Egyptian patients with chronic hepatitis C: a real-world experience

BACKGROUND

Simeprevir plus sofosbuvir (SIM/SOF) regimen was recommended by professional guidelines for certain patients with HCV genotype 1 infection and there is lack of data about this regimen in patients with genotype 4 infection.

AIM

To evaluate the efficacy and safety of this regimen in Egyptian patients with chronic HCV genotype 4 infection in the real world.

METHODS

Multicentre observational study included 583 patients with HCV genotype 4 infection who began 12 weeks of treatment with SIM plus SOF. Demographic, clinical and virological data as well as adverse outcomes were collected. Treatment naïve patients were 342 (59%) of all included patients, 45% of patients had severe fibrosis (F3 and F4) while 55% had mild fibrosis (F1 and F2) and the primary outcome was sustained virological response (SVR).

RESULTS

The overall SVR rate was 95.7% (558 out of 583 patients). In total, SVR12 in naïve patients with mild fibrosis score (F1 and F2) was achieved in 98.9% (94/95) for F1 and 98.1% (105/107) for F2, while naïve patients with severe fibrosis (F3 and F4) achieved SVR of 97.7% (86/88) for F3 and (42/52) 80.8% for F4. SVR in patients with previous interferon treatment achieved in 100% (45/45) for patients with F1 and 98.7% (74/75) for F2. While 94.7% (72/76) in experienced patients with F3; and 88.9% (40/45) for F4 achieved SVR12. Notable side effects included rash in 21 patients, photosensitivity in 18 patients, pruritus in 44 patients and hyperbilirubinemia in 42 patients.

CONCLUSIONS

A 12-week regimen of simeprevir/sofosbuvir was efficacious and well tolerated by treatment-naïve and treatment-experienced patients with chronic HCV genotype 4.

Direct-acting antivirals for chronic hepatitis C

BACKGROUND

Millions of people worldwide suffer from hepatitis C, which can lead to severe liver disease, liver cancer, and death. Direct-acting antivirals (DAAs), e.g. sofosbuvir, are relatively new and expensive interventions for chronic hepatitis C, and preliminary results suggest that DAAs may eradicate hepatitis C virus (HCV) from the blood (sustained virological response). Sustained virological response (SVR) is used by investigators and regulatory agencies as a surrogate outcome for morbidity and mortality, based solely on observational evidence. However, there have been no randomised trials that have validated that usage.

OBJECTIVES

To assess the benefits and harms of DAAs in people with chronic HCV.

SEARCH METHODS

We searched for all published and unpublished trials in The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, LILACS, and BIOSIS; the Chinese Biomedical Literature Database (CBM), China Network Knowledge Information (CNKI), the Chinese Science Journal Database (VIP), Google Scholar, The Turning Research into Practice (TRIP) Database, ClinicalTrials.gov, European Medicines Agency (EMA) (www.ema.europa.eu/ema/), WHO International Clinical Trials Registry Platform (www.who.int/ictrp), the Food and Drug Administration (FDA) (www.fda.gov), and pharmaceutical company sources for ongoing or unpublished trials. Searches were last run in October 2016.

SELECTION CRITERIA

Randomised clinical trials comparing DAAs versus no intervention or placebo, alone or with co-interventions, in adults with chronic HCV. We included trials irrespective of publication type, publication status, and language.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were hepatitis C-related morbidity, serious adverse events, and health-related quality of life. Our secondary outcomes were all-cause mortality, ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, hepatocellular carcinoma, non-serious adverse events (each reported separately), and SVR. We systematically assessed risks of bias, performed Trial Sequential Analysis, and followed an eight-step procedure to assess thresholds for statistical and clinical significance. We evaluated the overall quality of the evidence, using GRADE.

MAIN RESULTS

We included a total of 138 trials randomising a total of 25,232 participants. The trials were generally short-term trials and designed primarily to assess the effect of treatment on SVR. The trials evaluated 51 different DAAs. Of these, 128 trials employed matching placebo in the control group. All included trials were at high risk of bias. Eighty-four trials involved DAAs on the market or under development (13,466 participants). Fifty-seven trials administered DAAs that were discontinued or withdrawn from the market. Study populations were treatment-naive in 95 trials, had been exposed to treatment in 17 trials, and comprised both treatment-naive and treatment-experienced individuals in 24 trials. The HCV genotypes were genotype 1 (119 trials), genotype 2 (eight trials), genotype 3 (six trials), genotype 4 (nine trials), and genotype 6 (one trial). We identified two ongoing trials.We could not reliably determine the effect of DAAs on the market or under development on our primary outcome of hepatitis C-related morbidity or all-cause mortality. There were no data on hepatitis C-related morbidity and only limited data on mortality from 11 trials (DAA 15/2377 (0.63%) versus control 1/617 (0.16%); OR 3.72, 95% CI 0.53 to 26.18, very low-quality evidence). We did not perform Trial Sequential Analysis on this outcome.There is very low quality evidence that DAAs on the market or under development do not influence serious adverse events (DAA 5.2% versus control 5.6%; OR 0.93, 95% CI 0.75 to 1.15 , 15,817 participants, 43 trials). The Trial Sequential Analysis showed that there was sufficient information to rule out that DAAs reduce the relative risk of a serious adverse event by 20% when compared with placebo. The only DAA that showed a lower risk of serious adverse events when meta-analysed separately was simeprevir (OR 0.62, 95% CI 0.45 to 0.86). However, Trial Sequential Analysis showed that there was not enough information to confirm or reject a relative risk reduction of 20%, and when one trial with an extreme result was excluded, the meta-analysis result showed no evidence of a difference.DAAs on the market or under development may reduce the risk of no SVR from 54.1% in untreated people to 23.8% in people treated with DAA (RR 0.44, 95% CI 0.37 to 0.52, 6886 participants, 32 trials, low quality evidence). Trial Sequential Analysis confirmed this meta-analysis result.Only 1/84 trials on the market or under development assessed the effects of DAAs on health-related quality of life (SF-36 mental score and SF-36 physical score).There was insufficient evidence from trials on withdrawn or discontinued DAAs to determine their effect on hepatitis C-related morbidity and all-cause mortality (OR 0.64, 95% CI 0.23 to 1.79; 5 trials, very low-quality evidence). However, these DAAs seemed to increase the risk of serious adverse events (OR 1.45, 95% CI 1.22 to 1.73; 29 trials, very low-quality evidence). Trial Sequential Analysis confirmed this meta-analysis result.None of the 138 trials provided useful data to assess the effects of DAAs on the remaining secondary outcomes (ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, and hepatocellular carcinoma).

AUTHORS' CONCLUSIONS

The evidence for our main outcomes of interest come from short-term trials, and we are unable to determine the effect of long-term treatment with DAAs. The rates of hepatitis C morbidity and mortality observed in the trials are relatively low and we are uncertain as to how DAAs affect this outcome. Overall, there is very low quality evidence that DAAs on the market or under development do not influence serious adverse events. There is insufficient evidence to judge if DAAs have beneficial or harmful effects on other clinical outcomes for chronic HCV. Simeprevir may have beneficial effects on risk of serious adverse event. In all remaining analyses, we could neither confirm nor reject that DAAs had any clinical effects. DAAs may reduce the number of people with detectable virus in their blood, but we do not have sufficient evidence from randomised trials that enables us to understand how SVR affects long-term clinical outcomes. SVR is still an outcome that needs proper validation in randomised clinical trials.

Direct-acting antivirals for chronic hepatitis C

BACKGROUND

Millions of people worldwide suffer from hepatitis C, which can lead to severe liver disease, liver cancer, and death. Direct-acting antivirals (DAAs) are relatively new and expensive interventions for chronic hepatitis C, and preliminary results suggest that DAAs may eradicate hepatitis C virus (HCV) from the blood (sustained virological response). However, it is still questionable if eradication of hepatitis C virus in the blood eliminates hepatitis C in the body, and improves survival and leads to fewer complications.

OBJECTIVES

To assess the benefits and harms of DAAs in people with chronic HCV.

SEARCH METHODS

We searched for all published and unpublished trials in The Cochrane Hepato-Biliary Group Controlled Trials Register, CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, LILACS, and BIOSIS; the Chinese Biomedical Literature Database (CBM), China Network Knowledge Information (CNKI), the Chinese Science Journal Database (VIP), Google Scholar, The Turning Research into Practice (TRIP) Database, ClinicalTrials.gov, European Medicines Agency (EMA) (www.ema.europa.eu/ema/), WHO International Clinical Trials Registry Platform (www.who.int/ictrp), the Food and Drug Administration (FDA) (www.fda.gov), and pharmaceutical company sources for ongoing or unpublished trials. Searches were last run in October 2016.

SELECTION CRITERIA

Randomised clinical trials comparing DAAs versus no intervention or placebo, alone or with co-interventions, in adults with chronic HCV. We included trials irrespective of publication type, publication status, and language.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were hepatitis C-related morbidity, serious adverse events, and quality of life. Our secondary outcomes were all-cause mortality, ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, hepatocellular carcinoma, non-serious adverse events (each reported separately), and sustained virological response. We systematically assessed risks of bias, performed Trial Sequential Analysis, and followed an eight-step procedure to assess thresholds for statistical and clinical significance. The overall quality of the evidence was evaluated using GRADE.

MAIN RESULTS

We included a total of 138 trials randomising a total of 25,232 participants. The 138 trials assessed the effects of 51 different DAAs. Of these, 128 trials employed matching placebo in the control group. All included trials were at high risk of bias. Eighty-four trials involved DAAs on the market or under development (13,466 participants). Fifty-seven trials administered withdrawn or discontinued DAAs. Trial participants were treatment-naive (95 trials), treatment-experienced (17 trials), or both treatment-naive and treatment-experienced (24 trials). The HCV genotypes were genotype 1 (119 trials), genotype 2 (eight trials), genotype 3 (six trials), genotype 4 (nine trials), and genotype 6 (one trial). We identified two ongoing trials.Meta-analysis of the effects of all DAAs on the market or under development showed no evidence of a difference when assessing hepatitis C-related morbidity or all-cause mortality (OR 3.72, 95% CI 0.53 to 26.18, P = 0.19, I² = 0%, 2,996 participants, 11 trials, very low-quality evidence). As there were no data on hepatitis C-related morbidity and very few data on mortality (DAA 15/2377 (0.63%) versus control 1/617 (0.16%)), it was not possible to perform Trial Sequential Analysis on hepatitis C-related morbidity or all-cause mortality.Meta-analysis of all DAAs on the market or under development showed no evidence of a difference when assessing serious adverse events (OR 0.93, 95% CI 0.75 to 1.15, P = 0.52, I² = 0%, 15,817 participants, 43 trials, very low-quality evidence). The Trial Sequential Analysis showed that the cumulative Z-score crossed the trial sequential boundary for futility, showing that there was sufficient information to rule out that DAAs compared with placebo reduced the relative risk of a serious adverse event by 20%. The only DAA that showed a significant difference on risk of serious adverse events when meta-analysed separately was simeprevir (OR 0.62, 95% CI 0.45 to 0.86). However, Trial Sequential Analysis showed that there was not enough information to confirm or reject a relative risk reduction of 20%, and when one trial with an extreme result was excluded, then the meta-analysis result showed no evidence of a difference.DAAs on the market or under development seemed to reduce the risk of no sustained virological response (RR 0.44, 95% CI 0.37 to 0.52, P < 0.00001, I² = 77%, 6886 participants, 32 trials, very low-quality evidence) and Trial Sequential Analysis confirmed this meta-analysis result.Only 1/84 trials on the market or under development assessed the effects of DAAs on health-related quality of life (SF-36 mental score and SF-36 physical score).Withdrawn or discontinued DAAs had no evidence of a difference when assessing hepatitis C-related morbidity and all-cause mortality (OR 0.64, 95% CI 0.23 to 1.79, P = 0.40, I² = 0%; 5 trials, very low-quality evidence). However, withdrawn DAAs seemed to increase the risk of serious adverse events (OR 1.45, 95% CI 1.22 to 1.73, P = 0.001, I² = 0%, 29 trials, very low-quality evidence), and Trial Sequential Analysis confirmed this meta-analysis result.Most of all outcome results were short-term results; therefore, we could neither confirm nor reject any long-term effects of DAAs. None of the 138 trials provided useful data to assess the effects of DAAs on the remaining secondary outcomes (ascites, variceal bleeding, hepato-renal syndrome, hepatic encephalopathy, and hepatocellular carcinoma).

AUTHORS' CONCLUSIONS

Overall, DAAs on the market or under development do not seem to have any effects on risk of serious adverse events. Simeprevir may have beneficial effects on risk of serious adverse event. In all remaining analyses, we could neither confirm nor reject that DAAs had any clinical effects. DAAs seemed to reduce the risk of no sustained virological response. The clinical relevance of the effects of DAAs on no sustained virological response is questionable, as it is a non-validated surrogate outcome. All trials and outcome results were at high risk of bias, so our results presumably overestimate benefit and underestimate harm. The quality of the evidence was very low.

IL-10 and IL-28B gene variants as predictors of sustained response to peginterferon and ribavirin therapy in chronic HCV infection

OBJECTIVES

Interleukin-10 (IL-10) plays an important role in the immunity to hepatitis C virus (HCV). Insofar as IL-10 variants are associated with altered levels of IL-10, previous studies that examined the association of IL-10 polymorphisms with the susceptibility to and progression of chronic HCV, and response to anti-viral treatment were inconsistent. We investigated the association between common IL-10 variants in the intron and the promotor region with HCV and associated features.

METHODS

Study subjects comprised 120 patients infected with HCV-1b, and treated with Peg-IFN/RBV. Genotyping of six IL-10 promoter variants in the intron region (rs1878672, rs1554286, rs1518111) and promotor region (rs1800872, rs1800871, rs1800896) were done by real-time PCR.

RESULTS

Compared to G/G, carriage of IL-10 rs1800896 (-1082A/G) A/A genotype was more frequent in patients with sustained virological response (SVR). The decline in viral load over the first 12weeks of treatment was more pronounced in rs1800896 A/A genotype carriers, compared to G/G genotype carriers, and was irrespective of the treatment dosage. Carriage of rs1800896 A/A genotype was positively associated with improvement in viral load decline, which was simultaneous, with and without carriage of the common favourable IL-28B variant. Carriage of both IL-10 rs1800896 G/G and IL-28B non-favourable genotype was associated with twice the risk of getting slow decline of viral load during treatment. Haploview analysis identified ACGCTA and CCGCTG haplotypes to be linked with excellent PegIFN/RBV cure rate, and complete HCV eradication. On the other hand, ACGCTG and CCGCTA haplotypes were associated with resistance to PegIFN/RBV treatment.

CONCLUSION

IL-10 rs1800896 variant markedly influences the clinical outcome of HCV infection, and is a determinant of the response to HCV treatment.

2015 Philip S. Portoghese Medicinal Chemistry Lectureship. Curing Hepatitis C Virus Infection with Direct-Acting Antiviral Agents: The Arc of a Medicinal Chemistry Triumph

The development of direct-acting antiviral agents that can cure a chronic hepatitis C virus (HCV) infection after 8-12 weeks of daily, well-tolerated therapy has revolutionized the treatment of this insidious disease. In this article, three of Bristol-Myers Squibb's HCV programs are summarized, each of which produced a clinical candidate: the NS3 protease inhibitor asunaprevir (64), marketed as Sunvepra, the NS5A replication complex inhibitor daclatasvir (117), marketed as Daklinza, and the allosteric NS5B polymerase inhibitor beclabuvir (142), which is in late stage clinical studies. A clinical study with 64 and 117 established for the first time that a chronic HCV infection could be cured by treatment with direct-acting antiviral agents alone in the absence of interferon. The development of small molecule HCV therapeutics, designed by medicinal chemists, has been hailed as "the arc of a medical triumph" but may equally well be described as "the arc of a medicinal chemistry triumph".

The impact of ribavirin on real-world adherence rates in hepatitis C patients treated with sofosbuvir plus simeprevir

Background

Combination therapy with sofosbuvir (SOF) and simeprevir (SIM) is used to treat patients with hepatitis C virus infection. It is currently unknown whether adding ribavirin (RBV) to SOF + SIM, which raises the pill count from two up to eight pills a day, impacts adherence. The aim of this study is to examine the impact of pill count on real-world adherence rates in patients treated with SOF + SIM with and without RBV.

Methods

This retrospective study assessed composite adherence to SOF and SIM over 12 weeks of treatment for two cohorts of hepatitis C patients: one initiating SOF + SIM therapy, and the other initiating SOF + SIM + RBV therapy. Analyses were conducted using MarketScan^® and Optum US commercial pharmacy claims and enrollment data. Adherence was adjusted by treatment regimen, age, sex, co-pay, presence/absence of cirrhosis, treatment history, and Charlson Comorbidity Index.

Results

There was a significant difference in composite unadjusted and adjusted adherence rates for SOF and SIM for the SOF + SIM vs SOF + SIM + RBV cohorts based on MarketScan data (unadjusted, 92.6% and 89.7%, respectively; P=0.0423; adjusted, 92.2% and 88.7%, respectively; P=0.0176), but not based on Optum data (unadjusted, 94.8% and 95.6%, respectively; P=0.5618; adjusted, 94.8% and 95.1%, respectively; P=0.8589). In the MarketScan and Optum databases, there were no statistical differences in unadjusted and adjusted adherence rates for SOF. Unadjusted and adjusted adherence rates for SIM were mixed, as they were for composite adherence.

Conclusion

The impact of the addition of RBV to SOF + SIM therapy was mixed. The impact of RBV on SOF adherence was not significant in either database.

The role of IL-28, IFN-γ, and TNF-α in predicting response to pegylated interferon/ribavirin in chronic HCV patients

The primary goal of HCV therapy is to achieve a sustained virological response (SVR). Many host and viral factors influence the treatment response. Cytokines play an important role in the defense against viral infections, where successful treatment of hepatitis C depends on a complex balance between pro- and anti-inflammatory responses. In the present study, we investigated the relationship between the presence and percentage of some cytokines (IL-28, IFN-γ, and TNF-α) regarding different clinicopathological parameters including response to therapy in chronic HCV patients using immunohistochemical technique. This study was carried out on 64 chronic HCV patients (34 responders and 30 non-responders). Of cases, 54% showed IL-28 expression, which was associated with low AST (p = 0.002) and low HAI score (p = 0.006). Of cases, 67 and 45% showed IFN-γ and TNF-α expression, respectively, where the median percentage of TNF-α expression was higher in grade II spotty necrosis compared to grade I. Some inflammatory cytokines expressed by intrahepatic inflammatory cells in chronic HCV patients promote inflammation and injury (pro-inflammatory) such as TNF-α. Other cytokines aid in resolving inflammation and injury (anti-inflammatory) such as IL-28. The balance between these cytokines will determine the degree of inflammatory state. None of the investigated cytokines proved its clear cut role in affecting response to therapy, however, their levels varied between responders and non-responders for further investigations to clarify.

Persistent hepatitis C virus infection impairs ribavirin antiviral activity through clathrin-mediated trafficking of equilibrative nucleoside transporter 1

Ribavirin (RBV) continues to be an important component of interferon-free hepatitis C treatment regimens, as RBV alone does not inhibit hepatitis C virus (HCV) replication effectively; the reason for this ineffectiveness has not been established. In this study, we investigated the RBV resistance mechanism using a persistently HCV-infected cell culture system. The antiviral activity of RBV against HCV was progressively impaired in the persistently infected culture, whereas interferon lambda 1 (IFN-λ1), a type III IFN, showed a strong antiviral response and induced viral clearance. We found that HCV replication in persistently infected cultures induces an autophagy response that impairs RBV uptake by preventing the expression of equilibrative nucleoside transporter 1 (ENT1). The Huh-7.5 cell line treated with an autophagy inducer, Torin 1, downregulated membrane expression of ENT1 and terminated RBV uptake. In contrast, the autophagy inhibitors hydroxychloroquine (HCQ), 3-methyladenine (3-MA), and bafilomycin A1 (BafA1) prevented ENT1 degradation and enhanced RBV antiviral activity. The HCV-induced autophagy response, as well as treatment with Torin 1, degrades clathrin heavy chain expression in a hepatoma cell line. Reduced expression of the clathrin heavy chain by HCV prevents ENT1 recycling to the plasma membrane and forces ENT1 to the lysosome for degradation. This study provides a potential mechanism for the impairment of RBV antiviral activity in persistently HCV-infected cell cultures and suggests that inhibition of the HCV-induced autophagy response could be used as a strategy for improving RBV antiviral activity against HCV infection.

IMPORTANCE

The results from this work will allow a review of the competing theories of antiviral therapy development in the field of HCV virology. Ribavirin (RBV) remains an important component of interferon-free hepatitis C treatment regimens. The reason why RBV alone does not inhibit HCV replication effectively has not been established. This study provides a potential mechanism for why RBV antiviral activity is impaired in persistently HCV-infected cell cultures and suggests that inhibition of the HCV-induced autophagy response could be used as a strategy to increase RBV antiviral activity against HCV infection. Therefore, it is anticipated that this work would generate a great deal of interest, not only among virologists but also among the general public.

A pill for HCV - myth or foreseeable future?

Weekly injections with pegylated-IFNa (PegIFN) combined with daily ribavirin (RBV) are still the standard of care for chronic hepatitis C in most of the world. Sustained virological response (SVR) of 40-50% for patients infected with HCV genotypes (GT) 1 or 4 and 70-90% for genotypes 2-3 are achieved with this regimen. Triple therapy, registered in both the EU and USA, utilizing the first-generation direct protease inhibitors is able to increase the SVR rates to 75%, but its use is restricted to patients infected with HCV GT1. Additional limitations include challenging dosing schedules, complex treatment algorithms, limited efficacy in patients with previous null response to PegIFN/RBV therapy and additional side effects. There is also an important need for more effective antiviral therapy for difficult-to-treat populations with PEG-IFN intolerance, particularly those with cirrhosis and non-responders to previous therapies. All-oral, IFN-free therapies are an evolutionary step for future anti-HCV therapies. Initial results of clinical studies conducted during the last year give hope for 'a pill for HCV' at least in selected CHC populations. In 2013 several clinical trials of all-oral anti-HCV therapies had been completed, first all-oral combination submitted for registration and some conclusions could be drawn. However, there is not yet a clear direction for IFN-free therapies in treatment naïve patients or more complex non-responders.

Comparison of dengue virus and HCV: from impact on global health to their RNA-dependent RNA polymerases

ABSTRACT: 

Upon the discovery of HCV, dengue virus (DENV) and other flaviviruses have served as models to unravel the biology and mechanisms at play during HCV replication. HCV research has rapidly become a well-established field. Recently, several specific anti-HCV antiviral drugs have been discovered and approved for use in the clinic. Now, the strong emergence of DENV in the world and the associated increasing burden is casting light back to dengue virology and anti-dengue drug discovery. HCV polymerase (NS5B) is a prime target in antiviral therapies, and the analogous DENV polymerase (NS5) is also becoming one. Although both enzymes share common fold and function to some extent, a significant amount of unique structural and functional features have to be clearly delineated to efficiently translate drug design potential between these two essential enzymes.

Increased baseline proinflammatory cytokine production in chronic hepatitis C patients with rapid virological response to peginterferon plus ribavirin

Background

Chronic hepatitis C (CHC) patients achieving rapid virological response (RVR) on PEG-IFN/ribavirin (P/R) therapy have high chance of sustained virological response (SVR). To analyze host immunological factors associated with RVR, viral kinetics, phenotype distribution and Th1/Th2 cytokine production by peripheral blood mononuclear cells (PBMC) were studied prior to and during P/R therapy.

Methods

TNF-α, IFN-γ, IL-2, IL-6, IL-4 and IL-10 production by PBMC were measured after Toll-like receptor 4 (TLR-4) or phorbol myristate acetate/Ionomycin stimulation in 20 healthy controls and in 50 CHC patients before receiving and during P/R therapy. RVR was achieved by 14, complete early virological response (cEVR) by 19 patients and 17 patients were null-responders (NR).

Results

Patients with RVR showed an increased baseline TNF-α and IL-6 production by TLR-4 activated monocytes and increased IFN-γ, decreased IL-4 and IL-10 production by lymphocytes compared to non-RVR patients. SVR was also associated with increased baseline TNF-α production and decreased IL-10 levels compared to patients who did not achieve SVR. Baseline IL-2 production was higher in cEVR compared to NR patients. Antiviral treatment increased TNF-α, IL-6 production by monocytes and IFN-γ secretion by lymphocytes and decreased IL-4 and IL-10 production by lymphocytes in cEVR compared to NR patients.

Conclusion

RVR was associated with increased baseline proinflammatory cytokine production by TLR-4 stimulated monocytes and by activated lymphocytes. In null-responders and in patients who did not achieve SVR both TLR-4 sensing function and proinflammatory cytokine production were impaired, suggesting that modulation of TLR activity and controlled induction of inflammatory cytokine production may provide further therapeutic strategy for CHC patients non-responding to P/R treatment.

The application and mechanism of action of ribavirin in therapy of hepatitis C

Ribavirin has been used as an antiviral agent for several decades. Although it has activity against numerous viruses, its major use clinically has been in the treatment of respiratory syncytial virus in paediatric patients and chronic HCV infection in both children and adults. This review highlights the clinical application and mechanism of action of ribavirin and discusses the future role of ribavirin in treatment of HCV where there are intense research efforts to improve therapy.

Roles of ITPA and IL28B genotypes in chronic hepatitis C patients treated with peginterferon plus ribavirin

It has been reported that inosine triphosphatase (ITPA) gene variants protect against ribavirin-induced anemia in patients treated for chronic hepatitis C. IL28B variants also influence the treatment response of peginterferon plus ribavirin treatment in these patients. In the present study, we examined how ITPA and IL28B genotypes have clinical impacts on treatment-induced hematotoxicities and treatment response in HCV-infected patients treated with peginterferon plus ribavirin. ITPA genotypes (rs1127354 and rs6051702) and IL28B genotype (rs8099917) were determined by TaqMan SNP assay. We compared clinical background, treatment course and treatment response in terms of these genotypes. Only IL28B rs8099917 major type could predict sustained virological response. ITPA rs1127354 major type leads to significantly greater ribavirin-induced anemia than ITPA rs1127354 minor type between days 0 and 84. We noticed that IL28B rs8099917 minor genotype was associated with higher reduction of neutrophils and platelets. ITPA rs1127354 is useful for the prediction of ribavirin-induced anemia in the early phase after the commencement of peginterferon plus ribavirin treatment and IL28B rs8099917 is useful for the prediction of sustained virological response. Use of the combination of these two genotypes could lead to safe and effective treatment of chronic hepatitis C patients.

Ribavirin exerts differential effects on functions of Cd4+ Th1, Th2, and regulatory T cell clones in hepatitis C

Ribavirin improves outcomes of therapy in chronic hepatitis C but its mode of action has still remained unclear. Since ribavirin has been proposed to modulate the host’s T cell responses, we studied its direct effects on CD4⁺ T cell clones with diverse functional polarization which had been generated from patients with chronic hepatitis C. We analysed in vitro proliferation ([³H] thymidine uptake) and cytokine responses (IL-10, IFN-gamma) at varying concentrations of ribavirin (0–10µg/ml) in 8, 9 and 7 CD4⁺ TH1, TH2 and regulatory T cell (Treg) clones, respectively. In co-culture experiments, we further determined effects of ribarivin on inhibition of TH1 and TH2 effector cells by Treg clones. All clones had been generated from peripheral blood of patients with chronic hepatitis C in the presence of HCV core protein. Ribavirin enhanced proliferation of T effector cells and increased production of IFN-gamma in TH1 clones, but had only little effect on IL-10 secretion in TH2 clones. However, ribavirin markedly inhibited IL-10 release in Treg clones in a dose dependent fashion. These Treg clones suppressed proliferation of T effector clones by their IL-10 secretion, and in co-culture assays ribavirin reversed Treg-mediated suppression of T effector cells. Our in vitro data suggest that - in addition to its immunostimulatory effects on TH1 cells - ribavirin can inhibit functions of HCV-specific Tregs and thus reverses Treg-mediated suppression of T effector cells in chronic hepatitis C.