Direct-acting antivirals for the treatment of chronic hepatitis C: open issues and future perspectives

The effect of different direct antivirals on hepatic steatosis in nondiabetic and naïve hepatitis C-infected Egyptian patients

Background

Hepatitis C is associated with metabolic effects and fatty liver disease. The effect of different direct antivirals on the liver steatosis, and the metabolic profile, still needs to be established. The aim of this study is to determine the effect of achieving the sustained virological response after 12 weeks (SVR-12 weeks) with different combinations of direct antiviral drugs, on the hepatic steatosis, and fibrosis presented by laboratory and transient elastography parameters. Our study population is nondiabetic, chronically infected HCV Egyptian patients and naïve to any form of HCV treatment.

Methods

This cohort study was carried on 100 nondiabetic HCV treatment-naïve patients attending the Hepatology Clinic, in the Gastroenterology and Hepatology Department, Ain Shams University, and Kobry El Koba Military Hospital. The patients were divided into four groups according to their treatment regimens as follows: group A: 25 patients who received sofosbuvir (400 mg) and daclatasvir (60 mg) daily for 12 weeks; group B: 25 patients who received sofosbuvir (400 mg) and ledipasvir (90 mg) daily for 12 weeks; group C: 25 patients who received ombitasvir (12.5 mg), paritaprevir (75 mg), and ritonavir (50 mg) daily for 12 weeks; and group D: 25 patients who received sofosbuvir (400 mg) and simeprevir (150 mg) daily for 12 weeks. All patients were subjected to the following investigations: HCV quantitative PCR before and after 12 weeks of treatment, clinical and laboratory metabolic evaluation including alfa-fetoprotein level, thyroid profile assessment, ferritin level, pelvi-abdominal ultrasound, and FibroScan examination.

Results

All patients achieved SVR after 12 weeks. FibroScan median decreased (P < 0.001) from 19.29 ± 6.97 kPa at baseline to 14.15 ± 6.48 kPa at SVR12. NAFLD score median increased from 1.88 (1.49-2.22) at baseline to 2.01 (1.61-2.33) after 12 weeks of treatment. The highest level of NAFLD score was in group C, and the lowest was in group B. The BMI mean decreased from 28.31 ± 1.53 at baseline to 28.07 ± 1.52 at SVR12. HbA1C level mean decreased from 5.73 ± 0.23 at baseline to 5.40 ± 0.24 at SVR12. In addition, liver enzymes, cholesterol, triglycerides, APRI score (AST-platelet ratio index), and HBA1C decreased after 12-week treatment with a statistically significant difference, while the mean LDL increased after 12 weeks of treatment.

Conclusions

DAAs affect the metabolic profile of the treated patients. There is a noticed improvement in the FibroScan, NAFLD score, and lipid profile after achieving the SVR-12 weeks. However, LDL is increased after viral cure, mostly due to viral-host molecular interaction.

Direct antiviral agents (DAAs) and their use in pregnant women with hepatitis C (HCV)

INTRODUCTION

Direct-Acting Antiviral Agents (DAAs) provide safer, efficacious, tolerable, and curative therapy for women with hepatitis C. Their preferred safety and efficacy profile make them potential therapies for the elimination of perinatal transmission of hepatitis C virus (HCV). However, DAAs are not currently recommended for use during pregnancy due to limited pharmacokinetic and safety data.

AREAS COVERED

This review covers the different DAA drug combinations, the available data on their pharmacodynamic and pharmacokinetic properties, how the physiology in pregnancy can potentially affect DAA drug disposition, known drug-drug interactions with DAAs, and available and planned epidemiological and pharmacokinetic studies on DAA use during pregnancy. Although no large randomized clinical trials or prospective cohort studies involving DAAs have been completed in pregnancy, the currently available studies demonstrate no significant changes in pharmacokinetics, and no major safety concerns in women with hepatitis C.

EXPERT OPINION

Initial pharmacokinetic and safety data suggest that DAAs have high efficacy and a low risk of adverse events during pregnancy. As more pharmacokinetic and epidemiologic data become available, DAAs could become a preferred option for treating HCV during pregnancy and elimination of perinatal transmission of hepatitis C virus.

Molecular docking analysis of fluoroquinolones and other natural and synthetic compounds with the HCV NS3 helicase

It is of an interest to document the molecular docking analysis of fluoroquinolones and other natural and synthetic compounds with the HCV NS3 helicase. Data shows that three fluoroquinolones interacted with the NS3 helicase in the catalytic region, targeting some of the amino acids known to play a crucial role in NS3 helicase activity. Similarly, binding energy shows that the fluoroquinolones were comparable to the thiazolpiperazinyl derivatives, while superior to several of the synthetic and natural derivatives. The results show three fluoroquinolones to be potent helicase inhibitors that can be repurposed as supplemental therapy against HCV especially in cases non-responsive to DAAAs.

The distribution of hepatitis C virus infection in Shanghai, China: a time-spatial study

BACKGROUND

Shanghai, as a pilot city of China to achieve the goal of eliminating hepatitis C, its strategy of allocating medical resources is a pressing problem to be solved. This study aims to infer the time-spatial clustering patterns of HCV-infected cases, and grasp the dynamic genotype distribution of HCV, thereby inform elimination strategies of HCV with efficacy and efficiency.

METHODS

Reported HCV cases including their demographic information in Shanghai city from 2005 to 2018 were released from the National Infectious Disease Reporting Information System, population data at community scale, geographical layers of hospitals, communities and districts were gathered from former research. Blood samples of HCV-infected individuals were collected during 2014-2018 from 24 sentinel hospitals, HCV-antibody test, qualitative nucleic acid test and NS5B/5'UTR gene amplification were performed accordingly to determine the genotypes of the specimen. Furthermore, global and local spatial self-correlation analysis of both acute and chronic HCV infections were conducted at community scale year by year, then time-spatial clusters of acute and chronic HCV infections and HCV genotype distribution of specimen collected from sentinel hospitals by districts were mapped by using Arcmap10.1.

RESULTS

A total of 2631 acute HCV cases and 15,063 chronic HCV cases were reported in Shanghai from 2005 to 2018, with a peak in 2010 and 2017, respectively. The mean age of chronic HCV patients was 49.70 ± 14.55 years, 3.34 ± 0.32 years older than the acute (t = 10.55, P-value < 0.01). The spatial distribution of acute HCV infection formed one primary cluster (Relative Risk = 2.71), and the chronic formed one primary cluster and three secondary clusters with Relative Risk ranged from 1.94 to 14.42, meanwhile, an overlap of 34 communities between acute and chronic HCV clusters were found with time period spans varied from 6 to 12 years. Genotype 1 (N = 257, 49.71%) was the most prevalent HCV genotype in Shanghai, genotype 3 infections have increased in recent years. Baoshan district presented cluster of acute HCV and the highest proportion of genotype 2, Pudong new area was the cluster of chronic HCV and occupied the highest proportion of genotype 3.

CONCLUSIONS

Despite the low prevalence of HCV infection, it is still needed to push forward the elimination process in Shanghai, as there is a certain amount of HCV infected people waiting to be treated. The time-spatial clustering patterns and the dynamic of HCV genotype distribution together indicated a changing constitution of different transmission routes of HCV infection, thus, a focused strategy may be needed for high-risk population related to genotype 3 infection like drug users, in addition to an enforcement of the existing measures of preventing the iatrogenic and hematogenic transmission of HCV.

COVID-19's toll on the elderly and those with diabetes mellitus - Is vitamin B12 deficiency an accomplice?

COVID-19 exacts a disproportionate toll on both the elderly and those with diabetes; these patients are more likely to require costly intensive care, longer hospitalisation, and die from complications. Nations would thus find it extremely difficult to either lift or sustain socially, economically, and politically damaging restrictions that keep this group of people safe. Without a vaccine, there is thus an urgent need to identify potential modifiable risk factors which can help manage overall fatality or recovery rates. Case fatality rates are highly variable between (and even within) nations; nutritional differences have been proposed to account significantly for this disparity. Indeed, vitamin B12 deficiency is a common denominator between the elderly and those with diabetes. The question on hand thus lies on whether managing B12 deficiencies will impact COVID-19 fatality outcome or recovery rates. Herein, we review the latest evidence that shows that B12 deficiency associates in multiple areas very similar to where COVID-19 exerts its damaging effects: immunologically; microbiologically; haematologically; and through endothelial cell signalling-supporting the hypothesis that B12 deficiency is a potential modifiable risk factor in our fight against COVID-19.

Impact of IL28B gene polymorphism on efficacy and safety of direct acting antivirals in hepatitis C Egyptian patients

Background Hepatitis C virus infection is one of the major causes of liver cirrhosis and hepatocellular carcinoma worldwide. IL28B gene polymorphism has a direct relation to the response of interferon-based regimens. However, the effect of IL28B gene polymorphism on efficacy of the new direct acting antivirals used in treatment of chronic hepatitis C Egyptian patients hasn't been studied yet. Objective This study aimed to investigate the frequency of IL28B genotypes and impact of its polymorphism on the efficacy and safety of two direct acting antiviral regimens. Setting Patients were recruited form faculty of Medicine Ain shams research institute, Cairo, Egypt. Methods Easy to treat chronic hepatitis C Egyptian patients were included in this prospective study. Patients were randomized into two groups, group 1 received sofosbuvir plus daclatasvir and group 2 received paritaprevir, ombitasvir and ritonavir plus ribavirin. Both treatment regimens were given for 3 months. Laboratory evaluation and IL28B rs 12979860 genotyping were performed at baseline. Follow ups were performed monthly. Fibrosis was assessed at baseline and after treatment. Main outcome measures The frequency of IL28B genotypes and their correlation with safety and efficacy of direct acting antiviral regimens. Results CT genotype was present in 52.42% of patients while CC and TT genotypes were present in 28.16% and 19.42% of patients, respectively. IL28B genotypes weren't correlated to sustained virologic response in both treatment groups. Baseline fibroscan scores didn't show any significant relations with IL28B genotypes. Aspartate aminotransferase/alanine aminotransferase ratio increased significantly at the end of treatment in group1. CC genotype had shown higher ratio values at the end of treatment in Group 2. Conclusion CT genotype is the predominant genotype in easy to treat HCV Egyptian patients. IL28B genotypes hasn't any predictive value on the efficacy or the safety of direct acting antiviral regimens.

Ages of hepatocellular carcinoma occurrence and life expectancy are associated with a UGT2B28 genomic variation

Background

Hepatocellular carcinoma (HCC) is an aggressive solid tumor. HCC occurred at younger and elder ages were considered driven by different oncogenic mechanisms, and they demonstrated distinct clinical courses.

Methods

A total of 382 HCC patients treated by surgical resections was analyzed.

Results

A univariate-multivariate analysis showed that viral etiology (chronic hepatitis B, C) and the UDP glucuronosyltransferase family 2 member B28 (UGT2B28) genomic variant rs2132039 were independently associated with the age at presentation of HCC (all adjusted P < 0.05). An extensive evaluations of clinicalpathological factors showed that the age (Odds ratio [OR], 1.016; 95% confidence interval [CI], 1.001–1.032; adjusted P = 0.037) and ascites (OR, 3.505; CI, 1.358–9.048; adjusted P = 0.010) were two independent factors associated with this genomic variant. The age was 54.1 ± 14.6 years for patients with the “TT” variant type, and 58.2 ± 13.7 years for those with the “Non-TT” variant type. The age disparity was most prominent in alcoholic patients (OR, 1.079; CI, 1.035–1.125; P < 0.001, age of “TT”, 49.6 ± 12.2; age of “non-TT”, 59.3 ± 10.7). This genomic variant was also associated with age of recurrence (P = 0.025), distant metastasis (P = 0.024) and HCC-related death (P = 0.008) in non-censored patients.

Conclusions

An UGT2B28 genomic variant was indicative of the age of HCC presentation, recurrence, distant metastasis and death.

Efficacy and Safety of Glecaprevir/Pibrentasvir in Patients Coinfected With Hepatitis C Virus and Human Immunodeficiency Virus Type 1: The EXPEDITION-2 Study

Background

Once-daily glecaprevir coformulated with pibrentasvir (glecaprevir/pibrentasvir) demonstrated high rates of sustained virologic response 12 weeks after treatment (SVR12) in patients with hepatitis C virus (HCV) genotype 1-6 infection. This phase 3 study evaluated the efficacy and safety of glecaprevir/pibrentasvir in patients with chronic HCV genotype 1-6 and human immunodeficiency virus type 1 (HIV-1) coinfection, including patients with compensated cirrhosis.

Methods

EXPEDITION-2 was a phase 3, multicenter, open-label study evaluating glecaprevir/pibrentasvir (300 mg/120 mg) in HCV genotype 1-6/HIV-1-coinfected adults without and with compensated cirrhosis for 8 and 12 weeks, respectively. Patients were either HCV treatment-naive or experienced with sofosbuvir, ribavirin, or interferon, and antiretroviral therapy (ART) naive or on a stable ART regimen. Treatment-experienced genotype 3-infected patients were excluded. The primary endpoint was the SVR12 rate.

Results

In total, 153 patients were enrolled, including 16 (10%) with cirrhosis. The SVR12 rate was 98% (n = 150/153; 95% confidence interval, 95.8-100), with no virologic failures in 137 patients treated for 8 weeks. One genotype 3-infected patient with cirrhosis had on-treatment virologic failure. Most adverse events were mild in severity; 4 patients (2.6%) had serious adverse events, all deemed unrelated to glecaprevir/pibrentasvir. Treatment discontinuation was rare (<1%). All patients treated with ART maintained HIV-1 suppression (<200 copies/mL) during treatment.

Conclusions

Glecaprevir/pibrentasvir for 8 weeks in noncirrhotic and 12 weeks in cirrhotic patients is a highly efficacious and well-tolerated treatment for HCV/HIV-1 coinfection, regardless of baseline HCV load or prior treatment with interferon or sofosbuvir.

Clinical trial registration

NCT02738138.

High SVR12 with 8-week and 12-week glecaprevir/pibrentasvir therapy: An integrated analysis of HCV genotype 1-6 patients without cirrhosis

BACKGROUND & AIMS

Glecaprevir plus pibrentasvir (G/P) is a pangenotypic, once-daily, ribavirin-free direct-acting antiviral (DAA) treatment for hepatitis C virus (HCV) infection. In nine phase II or III clinical trials, G/P therapy achieved rates of sustained virologic response 12 weeks after treatment (SVR12) of 93-100% across all six major HCV genotypes (GTs). An integrated efficacy analysis of 8- and 12-week G/P therapy in patients without cirrhosis with HCV GT 1-6 infection was performed.

METHODS

Data were pooled from nine phase II and III trials including patients with chronic HCV GT 1-6 infection without cirrhosis who received G/P (300 mg/120 mg) for either 8 or 12 weeks. Patients were treatment naïve or treatment experienced with peginterferon, ribavirin, and/or sofosbuvir; all patients infected with HCV GT 3 were treatment naïve. Efficacy was evaluated as the SVR12 rate.

RESULTS

The analysis included 2,041 patients without cirrhosis. In the intent-to-treat population, 943/965 patients (98%) achieved SVR12 when treated for eight weeks, and 1,060/1,076 patients (99%) achieved SVR12 when treated for 12 weeks; the difference in rates was not significant (p = 0.2). A subgroup analysis demonstrated SVR12 rates > 95% across baseline factors traditionally associated with lower efficacy. G/P was well tolerated, with one DAA-related serious adverse event (<0.1%); grade 3 laboratory abnormalities were rare.

CONCLUSIONS

G/P therapy for eight weeks in patients with chronic HCV GT 1-6 infection without cirrhosis achieved an overall SVR12 rate of 98% irrespective of baseline patient or viral characteristics; four additional weeks of treatment did not significantly increase the SVR12 rate, demonstrating that the optimal treatment duration in this population is eight weeks.

LAY SUMMARY

In this integrated analysis of nine clinical trials, patients with chronic HCV genotype 1-6 infection without cirrhosis were treated for either 8 or 12 weeks with the direct-acting antiviral regimen glecaprevir/pibrentasvir (G/P). The cure rate was 98% and 99% following 8 and 12 weeks of treatment, respectively; the difference in rates was not significant (p = 0.2), nor was there a significant difference in the cure rates across the two treatment durations on the basis of baseline patient or viral characteristics. These results, along with a favourable safety profile, indicate that G/P is a highly efficacious and well-tolerated pangenotypic eight-week therapy for most patients with chronic HCV infection.

Efficacy of Glecaprevir/Pibrentasvir for 8 or 12 Weeks in Patients With Hepatitis C Virus Genotype 2, 4, 5, or 6 Infection Without Cirrhosis

BACKGROUND & AIMS

Hepatitis C virus (HCV) has high genotypic diversity and global distribution. Agents that are effective against all major HCV genotypes, with shorter treatment duration, are needed to reduce disease burden. Glecaprevir (an NS3/4A protease inhibitor) and pibrentasvir (an NS5A inhibitor) have a high barrier to resistance and synergistic antiviral activity. We evaluated the safety and efficacy of 8 and 12 weeks' treatment with glecaprevir/pibrentasvir in patients with HCV genotype 2, 4, 5, or 6 infection without cirrhosis in 3 separate phase 3 trials.

METHODS

We performed 2 open label, single-arm studies (SURVEYOR-II, Part 4 and ENDURANCE-4) and a randomized, double-blind, placebo-controlled study (ENDURANCE-2). In the ENDURANCE-2 study, adult patients with untreated or previously treated HCV genotype 2 infection without cirrhosis were randomly assigned (2:1) to groups given once-daily oral glecaprevir/pibrentasvir (n = 202; 300 mg/120 mg) or placebo (n = 100) for 12 weeks. In the SURVEYOR-II, Part 4 and ENDURANCE-4 studies, adult patients with untreated or previously treated patients with HCV genotype 2, genotype 4, genotype 5, or genotype 6 infection, without cirrhosis, were given once-daily oral glecaprevir/pibrentasvir (n = 121 in ENDURANCE-4 and n = 145 in SURVEYOR-II) for 12 or 8 weeks, respectively. In all studies the primary endpoint was sustained virologic response at 12 weeks after treatment (SVR12) in the intention-to-treat population.

RESULTS

Among patients receiving glecaprevir/pibrentasvir for 8 weeks, rates of SVR12 were 98% (95% CI, 94.1-99.3) in those infected with HCV genotype 2 and 93% (95% CI, 83.6-97.3) in those infected with HCV genotypes 4, 5, or 6. Among patients receiving glecaprevir/pibrentasvir for 12 weeks, rates of SVR12 were 99.5% (95% CI, 98.5-100) in those infected with HCV genotype 2 and 99% (95% CI, 97.6-100) in those infected with HCV genotype 4, 5, or 6. No virologic failures occurred in patients with HCV genotype 4, 5, or 6 infections. The frequency and severity of adverse events in patients receiving glecaprevir/pibrentasvir were similar to those of patients who received placebo.

CONCLUSION

In 3 Phase 3 studies, 8 weeks' treatment with glecaprevir/pibrentasivr produced an SVR12 in at least 93% of patients with chronic HCV genotype 2, 4, 5, or 6 infection without cirrhosis, with virologic failure in less than 1%. The drug combination had a safety profile comparable to 12 week's treatment with glecaprevir/pibrentasvir. ClinicalTrials.gov numbers: NCT02640482 (ENDURANCE-2), NCT02636595 (ENDURANCE-4), and NCT02243293 (SURVEYOR-II).

Sofosbuvir/velpatasvir: A promising combination

Hepatitis C virus (HCV) affects 3% of the world population. It represents the main cause of chronic liver disease and is responsible for extra-hepatic complications, such as type 2 diabetes and cardiovascular diseases. HCV includes 7 genotypes differing in the nucleotide sequence variability, the geographic distribution, the rates of viral clearance, the risk of progression to liver fibrosis and to hepatocellular carcinoma, and the response to therapy. Last years have seen remarkable advances in the field of HCV infection with the approval of direct antiviral agents (DAAs) targeting key viral proteins involved in the HCV replication. Several oral regimens combining DAAs from different families have been developed and these regimens showed increased and sustained virological response rates to above 90% reducing the treatment duration to 12 wk or less. In particular, sofosbuvir, a nucleotide analogue nonstructural (NS)5B polymerase inhibitor, and velpatasvir, a NS5A inhibitor, have been tested in two phase 3 trials, the ASTRAL-2 (against HCV genotype 2) and the ASTRAL-3 (against HCV genotype 3), demonstrating to be effective, safe, and well tolerated in patients who were 18 years of age or older and had at least a 6-mo history of HCV infection with a compensated liver disease.

Naturally occurring, resistance-associated hepatitis C virus NS5A variants are linked to interleukin-28B genotype and are sensitive to interferon-based therapy

AIM

The presence of resistance-associated variants (RAV) may attenuate the efficacy of direct-acting antivirals (DAA) in combination therapy for hepatitis C. The aim of this study was to characterize the NS3 and NS5A regions of hepatitis C virus (HCV) in naturally occurring RAV.

METHODS

The NS3 and NS5A regions of HCV were amplified by nested polymerase chain reaction and their nucleotide sequences were determined by direct sequencing in 493 genotype 1b patients naive to DAA-based therapies. The effect of baseline RAV on response to pegylated interferon and ribavirin therapy was analyzed in 65 patients after stratification by interleukin (IL)-28B genotype.

RESULTS

The incidence of RAV was 7.9% in NS3 (V36I/L, 1.2%; T54S, 2.8%; Q80K/R, 3.0%; A156S, 0.2%; and D168E/T, 2.4%) and 20.2% in NS5A (L31I/M, 2.2%; and Y93H, 19.0%). The incidence in interferon experienced and naive patients was similar. The incidence of Y93H in NS5A was significantly higher in the IL-28B TT genotype (rs8099917) than non-TT (27.1% vs 9.5%, P < 0.001). The virological response to pegylated interferon plus ribavirin therapy was not affected by the presence of RAV in IL-28B TT genotype.

CONCLUSION

RAV, especially Y93H in the NS5A region, were highly prevalent in DAA naive patients with genotype 1b HCV in Japan and were linked to IL-28B TT genotype. Interferon-based therapy could be an alternative for patients with RAV because these variants did not attenuate the response to that therapy. The analysis of RAV may impact the selection of the optimal treatment strategy.

The impact of an educational program on HCV patient outcomes using boceprevir in community practices (OPTIMAL trial)

OBJECTIVES

Although effective, direct acting antiviral (DAA) therapies for genotype 1 (GT 1) hepatitis C virus (HCV) have been associated with compliance challenges. Additionally, treatment at predominantly community-based centers has been associated with low retention of patients on treatment and higher dropout rates. The OPTIMAL Phase IV interventional trial (ClinicalTrials.gov Identifier: NCT01405027) was designed to evaluate the impact of an education program for community investigator (CI) sites participating in a Chronic Liver Disease Foundation study treating chronic GT 1 HCV patients.

METHODS

This physician educational program was administered by 22 Hepatology Centers of Educational Expertise (HCEE) academic sites to 33 CI sites asked to participate from December 2011 to July 2012. The HCEE mentors from DAA-experienced academic sites educated those at CI sites on therapeutic management, practice, and patient outcomes through a series of four standardized educational sequence visits regarding the use of first generation HCV protease inhibitors and the overall treatment of HCV.

RESULTS

Treatment duration compliance rates for patients treated at CI sites versus those treated at HCEE academic sites were evaluable in 77 of 84 HCEE academic site patients, 102 of 113 patients treated at CI sites, and 179 of 197 overall patients. The treatment duration compliance rates for patients treated at HCEE academic sites, CI sites and overall were 85.4 ± 25.39%, 83.8 ± 27.37%, and 84.5 ± 26.48%, respectively, and did not differ statistically between the groups (p = 0.49). Almost half (47%) of the patients in the study achieved a sustained virological response for 24 weeks (SVR24) regardless of the type of site (p = 0.64). Safety profiles were similar at both HCEE and CI sites.

CONCLUSIONS

These results demonstrated that education of CI sites unfamiliar with DAAs resulted in patient outcomes consistent with those observed at DAA-experienced academic sites.

Patient and physician preferences for the treatment of chronic hepatitis C virus infections: does the perspective matter?

OBJECTIVES

The objectives of this study were to identify and quantify the factors driving patient and physician preferences for treatments of genotype 1 hepatitis C virus infection in the UK.

METHODS

A web survey was conducted, including 100 patients (50 treatment-naive and 50 treatment-experienced patients) and 50 physicians (gastroenterologists/ hepatologists and infectious disease specialists). A discrete-choice experiment was conducted to elicit the participants' preferences on the basis of seven attributes with four levels each: efficacy, that is probability of reaching sustained virologic response, treatment duration, treatment convenience (i.e. number of pills and/or injections), gastrointestinal problems, anaemia, dermatological problems and neuropsychological problems. The statistical analysis applied a mixed logit model to estimate preference weights and relative importance scores.

RESULTS

Results indicated that the sustained virologic response rate was the most important attribute to participants. Physicians placed an even greater weight on the efficacy of treatments with a relative importance score of 9.33 [95% confidence interval: (6.93-11.91)], as compared with 6.16 [95% confidence interval: (4.34-8.15)] for patients. Neuropsychological problems ranked second for patients and physicians, and were more important to treatment-naive patients than to treatment-experienced patients or physicians. Gastrointestinal problems, anaemia and dermatological problems were of minor importance to all participants. These findings may be explained by the improvement in the management of physical adverse reactions over the last few years, thus making treatment easier to tolerate.

CONCLUSIONS

This study is the first conjoint analysis assessing and comparing the preferences of patients and physicians in hepatitis C virus.

Daclatasvir + asunaprevir: first global approval

The combination of daclatasvir + asunaprevir [Daklinza(®) + Sunvepra(®) (Japan)], two direct-acting antiviral agents, has been developed by Bristol-Myers Squibb for the treatment of patients with chronic hepatitis C virus (HCV) genotype 1 infections, including those with compensated cirrhosis. Daclatasvir + asunaprevir has received its first global approval in this indication in Japan. Daclatasvir + asunaprevir is the first all-oral, interferon- and ribavirin-free regimen for this indication. This article summarizes the milestones in the development of daclatasvir + asunaprevir leading to this first approval for the treatment of chronic HCV genotype 1 infections.

Sofosbuvir, a Significant Paradigm Change in HCV Treatment

Nucleotide compounds like sofosbuvir, acyclovir, and tenofovir have proven to be amongst the most potent orally available antiviral treatments. These drugs exhibit high efficacy and a wide therapeutic index, with demonstrated utility in a number of chronic viral infections. The approval of Sovaldi™, brand name for sofosbuvir, by the U.S. Food and Drug Administration heralded improvements in chronic hepatitis C virus (HCV) treatment. Sofosbuvir was originally discovered by Pharmasset Corporation and named PSI-7977. It was subsequently acquired and advanced through phase 3 development by Gilead Sciences, Inc. In Sofosbuvir both a unique pharmacology and a high specificity for the HCV ribonucleic acid polymerase are present in a molecule that is well tolerated and highly efficacious. Phase 2 and 3 clinical trials have consistently demonstrated durable and high rates of sustained virologic response (SVR), curing patients in excess of 80% in all genotypes and >90% in treatment-naïve subjects being administered combination therapy with other agents. Harvoni(®) is the combination of sofosbuvir and the NS5A inhibitor ledipasvir in a fixed-dose oral tablet, and it has demonstrated high SVR rates in patients infected with HCV genotype 1, without the need for exogenous interferon and/or ribavirin. Here, we discuss the discovery, development, pharmacologic characterization, and results from the phase 3 trials of sofosbuvir. Hepatitis C is a chronic disease, for which most patients have been undiagnosed, are unwilling to start treatment, or are ineligible for treatment because of the high toxicity and low efficacy of interferon and ribavirin-based therapy. Clinical studies with sofosbuvir have demonstrated significant improvement over the prior standard of care, thus ushering in a new paradigm of HCV treatment and an update of treatment guidelines.

New era for management of chronic hepatitis C virus using direct antiviral agents: A review

The pegylated interferon regimen has long been the lone effective management of chronic hepatitis C with modest response. The first appearance of protease inhibitors included boceprevir and telaprevir. However, their efficacy was limited to genotype 1. Recently, direct antiviral agents opened the gate for a real effective management of HCV, certainly after FDA approval of some compounds that further paved the way for the appearance of enormous potent direct antiviral agents that may achieve successful eradication of HCV.

New treatments for chronic hepatitis C: an overview for paediatricians

Pegylated interferon (IFN) α-2a or 2b in combination with ribavirin for children aged 3 years and older is the standard treatment for paediatric chronic hepatitis C. This treatment regimen was developed firstly in adults. In recent years, a number of direct-acting antiviral agents (DAAs) are under development for treatment of chronic hepatitis C virus (HCV) infection. These agents block viral replication inhibiting directly one of the several steps of HCV lifecycle. DAAs are classified into several categories based on their molecular target: HCV NS3/4A protease inhibitors, HCV NS5B polymerase inhibitors and HCV NS5A inhibitors. Other promising compounds are cyclophilin A inhibitors, mi-RNA122 and IFN-λ. Several new drugs associations will be developed in the near future starting from the actual standard of care. IFN-based and IFN-free regimens are being studied in adults. In this constantly evolving scenario new drug regimens targeted and suitable for children would be possible in the next future. Especially for children, it is crucial to identify the right combination of drugs with the highest potency, barrier to resistance and the best safety profile.

Gut immune response in the presence of hepatitis C virus infection

Hepatitis C virus (HCV) is an important etiologic agent of hepatitis and a major cause of chronic liver infection that often leads to cirrhosis, fibrosis and hepatocellular carcinoma. Although, HCV is a hepatotropic virus, there is strong evidence that HCV could replicate extra-hepatic in the gastrointestinal tissue which could serve as a reservoir for HCV. The outcome of HCV infection depends mainly on the host innate and adaptive immune responses. Innate immunity against HCV includes mainly nuclear factor cells and activation of IFN-related genes. There is an immunologic link between the gut and the liver through a population of T-cells that are capable of homing to both the liver and gut via the portal circulation. However, little is known on the role of Gut immune response in HCV. In this review we discussed the immune regulation of Gut immune cells and its association with HCV pathogenesis, various outcomes of anti-HCV therapy, viral persistence and degree of liver inflammation. Additionally, we investigated the relationship between Gut immune responses to HCV and IL28B genotypes, which were identified as a strong predictor for HCV pathogenesis and treatment outcome after acute infection.

Genetic variability of the core protein in hepatitis C virus genotype 4 in Saudi Arabian patients and its implication on pegylated interferon and ribavirin therapy

Background

Hepatitis C virus (HCV) shows a remarkable genetic diversity, contributing to its high persistence and varied susceptibilities to antiviral treatment. Previous studies have reported that the substitution of amino acids in the HCV subgenotype 1b core protein in infected patients is associated with a poor response to pegylated interferon and ribavirin (PEG-IFN/RBV) combined therapy.

Objectives

Because the role of the core protein in HCV genotype 4 infections is unclear, we aimed in this study to compare the full-length core protein sequences of HCV genotype 4 between Saudi patients who responded (SVR) and did not respond (non-SVR) to PEG-IFN/RBV therapy.

Study design

Direct sequencing of the full-length core protein and bioinformatics sequence analysis were utilized.

Results

Our data revealed that there is a significant association between core protein mutations, particularly at position 70 (Arg⁷⁰Gln), and treatment outcome in HCV subgenotype 4d patients. However, HCV subgenotype 4a showed no significant association between core protein mutations and treatment outcome. In addition, amino acid residue at position 91 was well-conserved among studied patients where Cys⁹¹ is the dominant amino acid residue.

Conclusions

These findings provide a new insight into HCV genotype 4 among affected Saudi population where the knowledge of HCV core gene polymorphisms is inadequate.

Chronic hepatitis C genotype 1 virus: Who should wait for treatment?

Elucidation of the natural history of chronic hepatitis C (CHC) and the identification of risk factors for its progression to advanced liver disease have allowed many physicians to recommend deferral treatment (triple therapy) in favour of waiting for new drug availability for patients who are at low risk of progression to significant liver disease. Newer generation drugs are currently under development, and are expected to feature improved efficacy and safety profiles, as well as less complex and shorter duration delivery regimens, compared to the current standards of care. In addition, patients with cirrhosis and prior null responders have a low rate (around 15%) of achieving sustained virological response (SVR) with triple therapy, and physicians must also consider the decision to wait for new treatments in the future for these patients as well. Naïve patients are the most likely to achieve a close to 100% SVR rate; therefore, it may be advisable to recommend that patients with mild to moderate CHC should wait for the newer therapy options. In contrast, patients with advanced fibrosis and cirrhosis will be those with the greatest need for expedited therapeutic intervention. There remains a need, however, for establishing definitive clinical management guidelines to maximize the benefit of waiting for new drugs and minimize risk of side effects and non-response to the current triple therapy.

Daclatasvir: potential role in hepatitis C

Chronic hepatitis C virus (HCV) infection is responsible for the development of liver cirrhosis and hepatocellular carcinoma. It has been a tremendous burden on global health care systems. With the advent of a number of new direct-acting and host-targeting antiviral agents, current interferon-α- and ribavirin-based HCV therapy has started to move towards an interferon-sparing or even interferon-free strategy. In this regard, a recently identified NS5A inhibitor, daclatasvir, showed a great promise in clinical trials as another new class of direct-acting anti-HCV therapeutics, with a distinct mechanism of action. In this review, a variety of preclinical as well as clinical proof-of-concept studies of daclatasvir, including the studies of its discovery, mechanism of action, viral resistance, and host polymorphism profiles are reviewed. In addition, a role of daclatasvir in the future therapy for HCV patients is discussed briefly.