Daclatasvir plus peginterferon alfa and ribavirin for treatment-naive chronic hepatitis C genotype 1 or 4 infection: a randomised study

Recent advances in managing chronic HCV infection: focus on therapy in patients with severe liver disease

Chronic hepatitis C virus (HCV) infection still represents a major public health problem, as it is thought to be responsible for more than 350,000 deaths around the globe on a yearly basis. Fortunately, successful eradication of the virus has been associated with improved clinical outcome and reduced mortality rates. In the past few years, treatment has improved considerably by the implementation of direct-acting antivirals (DAAs). From 2014 onwards, sofosbuvir, simeprevir, daclatasvir, ledipasvir, paritaprevir, ombitasvir, and dasabuvir have been approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA). Regimens with various combinations of these new drugs, without the use of interferon (IFN), proved to be very effective and well tolerated, even among patients with advanced liver disease. Moreover, treatment duration could be shortened to 12 weeks in the majority of patients. The high costs of these DAAs, however, limit the availability of IFN-free therapy worldwide. Even in wealthy countries, it is deemed necessary to prioritize DAA treatment in order to limit the immediate impact on the health budget. As patients with advanced liver disease are in most need of HCV clearance, many countries decided to treat those patients first. In the current review, we focus on the currently available IFN-free treatment options for patients with cirrhosis. We discuss the virological efficacy as well as the clinical relevance of these regimens among this specific patient population.

The cost-effectiveness of daclatasvir-based regimens for the treatment of hepatitis C virus genotypes 1 and 4 in the UK

OBJECTIVE

This study aimed to determine the cost-effectiveness of daclatasvir in combination with other medicinal products for the treatment of patients with hepatitis C virus genotypes 1 and 4 and advanced liver disease in the UK.

METHODS

A published and validated Markov model designed to simulate the natural history of chronic hepatitis C was used to compare daclatasvir with relevant treatment options for patients with hepatitis C virus genotypes 1 and 4 and a METAVIR score of F3-F4. Patients were defined according to their treatment status; that is, naive, experienced or interferon ineligible/intolerant. Data inputs for the analysis were derived from published sources, UK-specific where possible. A lifetime horizon was used, with costs and benefits discounted at 3.5%.

RESULTS

Daclatasvir-based regimens are estimated to be cost-effective versus no treatment and established standard-of-care regimens, including telaprevir in combination with pegylated interferon-α+ribavirin (PR), boceprevir in combination with PR and PR alone (incremental cost-effectiveness ratio range: £3715-£15,408). The cost-effectiveness of daclatasvir-based regimens versus emerging regimens (sofosbuvir or simeprevir based) is less consistent, but was dominant or cost-effective (incremental cost-effectiveness ratio range: £1394-£28,393) in all except two scenarios.

CONCLUSION

Daclatasvir-based regimens are expected to be highly cost-effective for the majority patients with advanced disease versus relevant comparator regimens, including newer direct-acting antiviral regimens.

Recent Advances in Antiviral Therapy for Chronic Hepatitis C

Hepatitis C virus (HCV) infection is a major worldwide health problem. Chronic infection induces continuous inflammation in the liver, progression of hepatic fibrosis, eventual cirrhosis, and possible hepatocellular carcinoma. Eradication of the virus is one of the most important treatment aims. A number of promising new direct-acting antivirals (DAAs) have been developed over the past 10 years. Due to their increased efficacy, safety, and tolerability, interferon-free oral therapies with DAAs have been approved for patients with HCV, including those with cirrhosis. This review introduces the characteristics and results of recent clinical trials of several DAAs: NS3/4A protease inhibitors, NS5A inhibitors, and NS5B inhibitors. DAA treatment failure and prognosis after DAA therapy are also discussed.

Advances in hepatitis C therapy: What is the current state - what come's next?

Chronic hepatitis C virus (HCV) infection affects 80-160 million people worldwide and is one of the leading causes of chronic liver disease. It is only a few years ago that standard treatment regimes were based on pegylated interferon alpha and ribavirin. However, treatment of HCV has undergone a revolutionary change in recent years. The admission of the nucleotide polymerase inhibitor Sofosbuvir enabled an interferon-free regimen with direct antiviral agents (DAA). Meanwhile seven DAAs are available and can be applied in several combinations for 8 to 24 wk depending on HCV genotype and patient characteristics such as cirrhosis and chronic renal failure. High rates of sustained virological response (SVR) rates can be achieved with these novel drugs. Even in difficult to treat populations such as patients with liver cirrhosis, HCV-human immunodeficiency virus co-infections, after liver transplantion, or with chronic kidney disease comparable high rates of SVR can be achieved. The anticipated 2(nd) generation DAAs are strikingly effective in patients so far classified as difficult to treat including decompensated liver cirrhosis or post-transplant patients. These 2(nd) generations DAAs will have higher resistance barriers, higher antiviral effects and a pan-genotypic spectrum. This review highlights the current state of the art of antiviral treatment in hepatitis C and gives an outlook for upcoming therapies.

In Vitro Antiviral Activity and Resistance Profile Characterization of the Hepatitis C Virus NS5A Inhibitor Ledipasvir

Ledipasvir (LDV; GS-5885), a component of Harvoni (a fixed-dose combination of LDV with sofosbuvir [SOF]), is approved to treat chronic hepatitis C virus (HCV) infection. Here, we report key preclinical antiviral properties of LDV, including in vitro potency, in vitro resistance profile, and activity in combination with other anti-HCV agents. LDV has picomolar antiviral activity against genotype 1a and genotype 1b replicons with 50% effective concentration (EC50) values of 0.031 nM and 0.004 nM, respectively. LDV is also active against HCV genotypes 4a, 4d, 5a, and 6a with EC50 values of 0.11 to 1.1 nM. LDV has relatively less in vitro antiviral activity against genotypes 2a, 2b, 3a, and 6e, with EC50 values of 16 to 530 nM. In vitro resistance selection with LDV identified the single Y93H and Q30E resistance-associated variants (RAVs) in the NS5A gene; these RAVs were also observed in patients after a 3-day monotherapy treatment. In vitro antiviral combination studies indicate that LDV has additive to moderately synergistic antiviral activity when combined with other classes of HCV direct-acting antiviral (DAA) agents, including NS3/4A protease inhibitors and the nucleotide NS5B polymerase inhibitor SOF. Furthermore, LDV is active against known NS3 protease and NS5B polymerase inhibitor RAVs with EC50 values equivalent to those for the wild type.

Interferon lambda 4 genotypes and resistance-associated variants in patients infected with hepatitis C virus genotypes 1 and 3

Single-nucleotide polymorphisms (SNPs) in the interferon lambda 4 (IFNL4) gene are predictors for treatment success in patients with hepatitis C virus (HCV) infection. For direct-acting antiviral combinations only weak association with IFNL4 SNPs was observed. Little is known about potential selections of resistance-associated variants (RAVs) by the IFNL4 genotype. This study analyzed the prevalence of RAVs to currently approved direct-acting antivirals in a large European population in correlation to SNPs in IFNL4. Samples of 633 patients chronically infected with HCV genotypes 1a (n = 259), 1b (n = 323), and 3 (n = 51) were genotyped for rs12979860 (formerly known as IL28B) and rs368234815. RAVs in NS3, NS5A, and NS5B were detected by population-based sequencing. In addition, IFNL4 SNPs and NS5A RAVs were analyzed including deep sequencing (n = 109) in an independent replication cohort of HCV genotype 1-infected patients (n = 201). No significant correlation was found between IFNL4 SNPs and rare and common RAVs within NS3 and NS5B. In contrast, the NS5A RAV Y93H was detected frequently in HCV genotype 1b (14%) and significantly associated with the beneficial IFNL4 SNPs (P < 0.001 and P = 0.002, respectively). Moreover, the presence of Y93H in HCV genotype 1b patients was significantly associated with the second site variant T83M (P < 0.001). Independent factors significantly associated with the presence of Y93H were IFNL4 genotype and high baseline viral load.

CONCLUSION

The NS5A RAV Y93H is significantly associated with the presence of beneficial IFNL4 SNPs and a high baseline viral load in HCV genotype 1-infected patients, which may explain a lack of correlation or even an inverse correlation of treatment response with IFNL4 genotype in some NS5A inhibitor containing IFN-free regimens.

Efficacy of Second Generation Direct-Acting Antiviral Agents for Treatment Naïve Hepatitis C Genotype 1: A Systematic Review and Network Meta-Analysis

BACKGROUND

The treatment of hepatitis C (HCV) infections has significantly changed in the past few years due to the introduction of direct-acting antiviral agents (DAAs). DAAs could improve the sustained virological response compared to pegylated interferon with ribavirin (PR). However, there has been no evidence from randomized controlled trials (RCTs) that directly compare the efficacy among the different regimens of DAAs.

AIM

Therefore, we performed a systematic review and network meta-analysis aiming to compare the treatment efficacy between different DAA regimens for treatment naïve HCV genotype 1.

METHODS

Medline and Scopus were searched up to 25th May 2015. RCTs investigating the efficacy of second generation DAA regimens for treatment naïve HCV genotype 1 were eligible for the review. Due to the lower efficacy and more side effects of first generation DAAs, this review included only second generation DAAs approved by the US or EU Food and Drug Administration, that comprised of simeprevir (SMV), sofosbuvir (SOF), daclatasvir (DCV), ledipasvir (LDV), and paritaprevir/ritonavir/ombitasvir plus dasabuvir (PrOD). Primary outcomes were sustained virological response at weeks 12 (SVR12) and 24 (SVR24) after the end of treatment and adverse drug events (i.e. serious adverse events, anemia, and fatigue). Efficacy of all treatment regimens were compared by applying a multivariate random effect meta-analysis. Incidence rates of SVR12 and SVR24, and adverse drug events of each treatment regimen were pooled using 'pmeta' command in STATA program.

RESULTS

Overall, 869 studies were reviewed and 16 studies were eligible for this study. Compared with the PR regimen, SOF plus PR, SMV plus PR, and DVC plus PR regimens yielded significantly higher probability of having SVR24 with pooled risk ratios (RR) of 1.98 (95% CI 1.24, 3.14), 1.46 (95% CI: 1.22, 1.75), and 1.68 (95% CI: 1.14, 2.46), respectively. Pooled incidence rates of SVR12 and SVR24 in all treatment regimens without PR, i.e. SOF plus LDV with/without ribavirin, SOF plus SMV with/without ribavirin, SOF plus DCV with/without ribavirin, and PrOD with/without ribavirin, (pooled incidence of SVR12 ranging from 93% to 100%, and pooled incidence of SVR24 ranging from 89% to 96%) were much higher than the pooled incidence rates of SVR12 (51%) and SVR24 (48%) in PR alone. In comparing SOF plus LDV with ribavirin and SOF plus LDV without ribavirin, the chance of having SVR12 was not significantly different between these two regimens, with the pooled RR of 0.99 (95% CI: 0.97, 1.01). Regarding adverse drug events, risk of serious adverse drug events, anemia and fatigue were relatively higher in treatment regimens with PR than the treatment regimens without PR. The main limitation of our study is that a subgroup analysis according to dosages and duration of treatment could not be performed. Therefore, the dose and duration of recommended treatment have been suggested in range and not in definite value.

CONCLUSIONS

Both DAA plus PR and dual DAA regimens should be included in the first line drug for treatment naïve HCV genotype 1 because of the significant clinical benefits over PR alone. However, due to high drug costs, an economic evaluation should be conducted in order to assess the value of the investment when making coverage decisions.

Management of HCV in cirrhosis-a rapidly evolving landscape

Despite the rapid progress in treatment, chronic hepatitis C virus (HCV) infection remains a growing cause of liver-related mortality globally. Patients who have been infected for decades are now presenting with advanced liver disease with the complications of cirrhosis and liver cancer. Early attempts at treatment with peginterferon and ribavirin were limited by toxicity, long treatment duration, and limited efficacy. This was especially relevant for patients with cirrhosis, where exposure to peginterferon-based therapy was relatively ineffective and led to high rates of toxicity. However, the recent development of multiple novel direct-acting antivirals (DAAs) has revolutionized the treatment of HCV. The majority of patients can now be cured with short courses of extremely well-tolerated all-oral regimens. However, the real test of these regimens comes in patients with more advanced liver disease, both in terms of safety and efficacy. Patients with cirrhosis have the greatest need for therapy and have traditionally been the most difficult to cure. The new therapies are rapidly changing this paradigm. Accumulating data suggest that high cure rates are achievable in patients with compensated cirrhosis and may even be possible in patients with signs of liver failure. This review will focus on the treatment of HCV in patients with cirrhosis, with an emphasis on the challenges that remain and strategies to deal with this important population.

Hepatitis C genotype 4: The past, present, and future

Hepatitis C virus (HCV) genotype (GT) 4 represents 12%-15% (15-18 million) of total global HCV infection. It is prevalent in Northern and Equatorial Africa and the Middle East, and is also present in some countries in Europe. GT-4 (and subtype 4a in particular) dominates the HCV epidemic in Egypt. In underdeveloped countries, risk factors associated with HCV infection may be due to unsafe medical practices or other factors such as familial transmission, mother’s HCV status, or illiteracy. HCV prevention and control programs should include health education, increased community awareness towards the disease, controlling infection distribution in health-care centers, proper sterilization of medical and dental instruments, and ensuring safe supply of blood and blood-products. Response rates to a 48-wk combined pegylated-interferon (PEG-IFN) and ribavirin (RBV) treatment range from 40%-69%, and HCV-GT-4 has been considered better than GT-1 but worse than GT-2 and GT-3 in treatment with PEG-IFN/RBV. However, with the introduction of the HCV-GT-1 effective protease inhibitors boceprevir and telaprevir in 2011, HCV-GT-4 became the “most difficult (GT) to treat”. Recently, the direct-acting antivirals (DAAs) with pan- genotypic activities simeprevir, sofosbuvir, and daclatasvir have been recommended in triple regimens with PEG-IFN/RBV for the treatment of HCV-GT-4. An IFN-free regimen will be available for treatment of all genotypes of HCV in the near future. To date, several DAAs have been developed and are currently being evaluated in various combinations in clinical trials. As new regimens and new agents are being approved by the Food and Drug Administration, we can expect the guidelines for HCV treatment to be changed. The availability of shorter, simpler, and more tolerable treatment regimens can reduce the morbidity and mortality associated with HCV infection. With such a large number of therapeutic agents available, we can end up with a range of choices that we can select from to treat patients.

Low Efficacy of Pegylated Interferon plus Ribavirin plus Nitazoxanide for HCV Genotype 4 and HIV Coinfection

Background

Nitazoxanide (NTZ) plus pegylated interferon and ribavirin (Peg-IFN/RBV) improved the sustained virological response (SVR) achieved with Peg-IFN/RBV in hepatitis C virus genotype 4 (HCV-4)-monoinfected patients. There are no data currently on the efficacy of Peg-IFN/RBV plus NTZ for human immunodeficiency virus (HIV)/HCV-4 coinfection. Therefore, the objectives of this clinical trial were to assess the efficacy and to evaluate the safety of Peg-IFN/RBV plus NTZ in HIV/HCV-4-coinfected patients.

Patients and Methods

This was an open-label, single arm, multicenter phase II pilot clinical trial (NCT01529073) enrolling HIV-infected individuals with HCV-4 chronic infection, naïve to HCV therapy. Patients were treated with NTZ 500 mg bid for 4 weeks, followed by NTZ 500 mg bid plus Peg-IFN alpha-2b 1.5 μg/kg/week plus weight-adjusted RBV during 48 weeks. Analyses were done by intention-to-treat (ITT, missing = failure). A historical cohort of HIV/HCV-4-infected patients treated with Peg-IFN alpha-2b and RBV at the same area was used as control.

Results

Two (9.5%) of 21 patients included in the trial compared with 5 (21.7%) of 23 patients included in the historical cohort achieved SVR (SVR risk difference, -12.2%; 95% confidence interval, -33.2% to 8.8%; p = 0.416). Virological failure was due to lack of response in 13 (62%) individuals recruited in the trial. Two (9.5%) patients included in the trial and two (9.5%) individuals from the historical cohort discontinued permanently due to adverse events.

Conclusions

No increase in SVR was observed among HIV/HCV-4-coinfected patients receiving Peg-IFN/RBV plus NTZ compared with a historical cohort treated with Peg-IFN/RBV. Interruptions due to adverse events of Peg-IFN/RBV plus NTZ were similar to those of dual therapy.

Trial Registration

ClinicalTrials.gov NCT01529073

Hepatitis C Virus: Current and Evolving Treatments for Genotype 4

Hepatitis C virus (HCV) is a major cause of chronic liver disease, with more than 170 million infected individuals worldwide. Genotype 4 is the most frequent cause of chronic hepatitis C in the Middle East and sub-Saharan Africa. It has recently spread to southern Europe. The introduction of all-oral, interferon-free regimens that combine direct-acting antivirals (DAAs) has significantly advanced HCV treatment. High efficacy rates, short treatment duration, and favorable adverse event profiles have been demonstrated with multiple regimens, both with and without ribavirin. This review discusses management of patients with HCV genotype 4 chronic hepatitis, in the era of DAAs.

Hepatitis C virus treatment in the real world: optimising treatment and access to therapies

Chronic HCV infections represent a major worldwide public health problem and are responsible for a large proportion of liver related deaths, mostly because of HCV-associated hepatocellular carcinoma and cirrhosis. The treatment of HCV has undergone a rapid and spectacular revolution. In the past 5 years, the launch of direct acting antiviral drugs has seen sustained virological response rates reach 90% and above for many patient groups. The new treatments are effective, well tolerated, allow for shorter treatment regimens and offer new opportunities for previously excluded groups. This therapeutic revolution has changed the rules for treatment of HCV, moving the field towards an interferon-free era and raising the prospect of HCV eradication. This manuscript addresses the new challenges regarding treatment optimisation in the real world, improvement of antiviral efficacy in 'hard-to-treat' groups, the management of patients whose direct acting antiviral drug treatment was unsuccessful, and access to diagnosis and treatment in different parts of the world.

The new era of hepatitis C virus therapy

The hepatitis C virus (HCV) has a significant medical and economic impact on societies around the world, and it has been estimated that 130-180 million people are infected with HCV. Therapies for HCV are currently undergoing a revolution. In recent years, several new treatments have been approved by the United States Food and Drug Administration, and many other treatments are in phase II or III clinical trials, including direct antiviral agents (DAAs). Due to recent major advances in the field of HCV therapy, a summary of findings on new HCV therapies are provided in this review article, including reports on new DAAs.

Daclatasvir: A NS5A Replication Complex Inhibitor for Hepatitis C Infection

OBJECTIVES

To review the pharmacology, efficacy, and safety of daclatasvir in the treatment of patients with chronic hepatitis C virus (HCV) infection.

DATA SOURCES

A literature search through EMBASE and PubMed was conducted (January 1966 to August 2015) using the terms BMS-790052, daclatasvir, and hepatitis C. References from retrieved articles were reviewed for any additional material. Additionally, the new drug application and prescribing information were retrieved.

STUDY SELECTION/DATA EXTRACTION

The literature search was limited to human studies published in English. Phase 1, 2, and 3 studies describing the pharmacology, pharmacokinetics, efficacy, and safety of daclatasvir for HCV were identified.

DATA SYNTHESIS

Daclatasvir, a nonstructural 5A protein inhibitor, combined with sofosbuvir, is indicated for adult patients with chronic HCV genotype 3 regardless of treatment or cirrhosis status. The phase III ALLY-3 trial (n = 152) demonstrated that daclatasvir taken once daily with sofosbuvir for 12 weeks was effective at achieving sustained virological response (SVR) rates in treatment-naïve (97%) and treatment-experienced (94%) patients without cirrhosis. Patients with cirrhosis had significantly lower SVR rates (58 and 69%, respectively). The most common adverse drug events associated with daclatasvir and sofosbuvir in ALLY-3 were headache (20%), fatigue (19%), and nausea (12%).

CONCLUSIONS

Daclatasvir, when combined with sofosbuvir, is an effective agent to treat HCV genotype 3, with SVR rates above 90% for patients without cirrhosis who are treatment naïve or experienced. SVR rates for treatment-naïve or -experienced patients with cirrhosis are not as robust (58%-69%).

Impact of hepatitis C status on 20-year mortality of patients with substance use disorders

Background

The magnitude of the effect of hepatitis C viral infection on survival is still not fully understood. The objective of this study was to determine whether the presence of hepatitis C viral antibodies in 1991 was associated with increased mortality 20 years later within a cohort of patients with substance use disorders. Secondary objectives were to determine other factors that were associated with increased mortality in the cohort.

Methods

A subset of a 1991 study cohort of patients who had presented for detoxification was reexamined 20 years later. The Social Security Death Index was queried to identify which of the original patients had died. Attributes of survivors and non-survivors were compared, with special attention to their hepatitis C status in 1991. The original study and this analysis were conducted in the chemical detoxification unit at Johns Hopkins Bayview (previously Francis Scott Key Hospital), an academic urban hospital. All participants met the criteria for alcohol or opioid dependence at the time of admission in 1991. The primary study outcome was 20-year mortality after initial admission in 1991, with a planned analysis of hepatitis C status.

Results

Twenty years after admission, 362 patients survived and 82 had died. Of the 284 patients who were hepatitis C positive, 228 survived (80 %). Of the 160 patients who were hepatitis C negative, 134 survived (84 %). This absolute risk increase of 4 % was not statistically significant (p = 0.37). Factors associated with increased mortality included male sex, white race, older age, and reported use of alcohol, cocaine, and illicit methadone. Binary logistic regression including hepatitis C status and these other variables yielded an adjusted odds ratio of 0.87 (95 % CI 0.49–1.55); (p = 0.64) for hepatitis C positive 20-year survival.

Conclusions

Hepatitis C positivity was not associated with a statistically significant difference in 20-year survival. The effect of the virus on mortality, if present, is small, relative to the effect of substance use disorders alone.

Potential genetic markers for prediction of treatment response in Egyptian children infected with HCV genotype 4

BACKGROUND

Egypt has a high prevalence of hepatitis C virus (HCV) infection. Limitations of the current HCV treatment in children are low rate of sustained virological response, significant side effects and high expenses, making prediction of treatment response crucial.

AIM

This study aimed to investigate association of single nucleotide polymorphisms (SNPs) in interleukins (IL) 10, 28 and 29 genes in predicting the response to therapy in HCV infected children.

METHODS

Sixty-six Egyptian children infected with HCV genotype 4, receiving pegylated interferon alpha 2b and ribavirin, were included. Genotyping of six SNPs in interleukin 10, 28B and 29 gene as well as HCV genotype were analyzed by real-time polymerase chain reaction.

RESULTS

The CC genotype in IL28B; rs12979860 had 8.547 folds higher chance to develop sustained virological response than CT and TT genotypes (P=0.014). Genotype distribution of rs8099917 in IL28B gene (TG and GG genotypes) was found to be 3.348 more likely not to respond to treatment than the TT genotype (P=0.018). In multivariate analysis, interleukin 28 gene single nucleotide polymorphisms rs 12979860, interleukin 10 single nucleotide polymorphisms -592A > C and basal viral load were independent variables that significantly improved prediction of response to HCV therapy.

CONCLUSION

This association can be translated into clinical decision making for HCV treatment.

Therapy for hepatitis C genotype 3: moving forward

Until recently, the standard of care for hepatitis C virus genotype 3 infection was response-guided therapy with pegylated interferon plus ribavirin for 16 to 48 or 72 weeks. The introduction of sofosbuvir plus ribavirin has revolutionized hepatitis C virus therapy. Nowadays, the recommend treatment regimen is a combination of sofosbuvir and a weight-based ribavirin dose for 24 weeks. For easy to treat patients (e.g. naïve or previously treated patients without cirrhosis), this combination achieves high sustained virologic response rates and is well tolerated. However, in treatment-experienced patients with cirrhosis, sustained virologic response is lower due to unknown reasons. The combination of two direct-acting antiviral agents, sofosbuvir and daclatasvir, for 12 weeks is also associated with low sustained virologic response rates in this special population, for whom new drugs and different strategies are now under evaluation. Currently, the high cost of all these drugs limits access to treatment in many countries.

Efficacy and safety of sofosbuvir-based triple therapy in hepatitis C genotype 4 infection

BACKGROUND

There are only limited data on sofosbuvir-based treatment regimens in hepatitis C virus (HCV) genotype 4-infected patients.

AIMS

To evaluate safety and efficacy of sofosbuvir-based triple-therapy in HCV genotype 4 infection.

METHODS

All HCV genotype 4-infected patients who started sofosbuvir-based triple-therapy at our two centres between January and June 2014 were prospectively included (N=24) and compared to genotype 4 patients treated with peginterferon/ribavirin between January 2001 and December 2012 (N=63).

RESULTS

The demographics in the sofosbuvir group and the controls were comparable (males 87.5% and 82.5%; mean age 46.7±9.0 years and 42.0±9.8 years, respectively). Sustained virological response was achieved in 83.3% in the sofosbuvir group and in 47.6% of controls (P=0.003). Fatigue (P=0.007), flu-like (P=0.015), gastrointestinal (P<0.001), dermatologic (P<0.001) and psychiatric symptoms (P=0.022) were more common in the control group.

CONCLUSIONS

In our real-life cohort, sofosbuvir-based triple therapy confirmed its high efficacy and safety for chronic genotype 4 hepatitis C.

Randomized controlled trial of the NS5A inhibitor daclatasvir plus pegylated interferon and ribavirin for HCV genotype-4 (COMMAND-4)

BACKGROUND

Treatment options for HCV genotype-4 (GT4) are limited. This Phase III study (COMMAND-4; AI444-042) evaluated the efficacy and safety of daclatasvir (DCV), a pan-genotypic HCV NS5A inhibitor, with pegylated interferon-α2a/ribavirin (PEG-IFN/RBV) in treatment-naive patients with HCV GT4 infection.

METHODS

Patients were randomly assigned (2:1; blinded) to treatment with DCV 60 mg (n=82) or placebo (n=42) once daily plus PEG-IFN 180 µg weekly and RBV 1,000-1,200 mg/day (weight-based) twice daily. DCV-treated patients with undetectable HCV RNA at weeks 4 and 12 (eRVR) received 24 weeks of DCV plus PEG-IFN/RBV; those without eRVR received an additional 24 weeks of PEG-IFN/RBV. All placebo-treated patients received 48 weeks of PEG-IFN/RBV. The primary end point was sustained virological response (SVR) at post-treatment week 12 (SVR12).

RESULTS

Patients were 75% IL28B non-CC and 11% had cirrhosis. SVR rates (HCV RNA < lower limit of quantitation [LLOQ]) at post-treatment week 12 or later (imputed to include patients missing SVR12 assessments but had SVR after post-treatment week 12) were 82% (67/82) with DCV plus PEG-IFN/RBV versus 43% (18/42) with PEG-IFN/RBV (P<0.0001). In DCV recipients, SVR12 rates were comparable across subgroups. The safety and tolerability profile of DCV plus PEG-IFN/RBV was comparable to that of PEG-IFN/RBV. Discontinuations due to adverse events occurred in 4.9% of patients receiving DCV plus PEG-IFN/RBV and 7.1% of patients receiving PEG-IFN/RBV.

CONCLUSIONS

In treatment-naive patients with HCV GT4 infection, DCV plus PEG-IFN/RBV achieved higher SVR12 rates than PEG-IFN/RBV alone. These data support DCV-based regimens for treatment of HCV GT4 infection, including all-oral combinations with other direct-acting antivirals (AI444-042; ClinicalTrials.gov NCT01448044).

Hepatitis C virus genotype 4 resistance and subtype demographic characterization of patients treated with ombitasvir plus paritaprevir/ritonavir

Hepatitis C virus (HCV) genotype 4 (GT4) is genetically diverse, with 17 confirmed subtypes, and comprises approximately 13% of infections worldwide. In this study, we identified GT4 subtypes by phylogenetic analysis, assessed differences in patient demographics across GT4 subtypes, examined baseline sequence variability among subtypes and the potential impact on treatment outcome, and analyzed the development of viral resistance in patients who received a regimen of ombitasvir (nonstructural protein 5A [NS5A] inhibitor) plus ritonavir-boosted paritaprevir (NS3/4A inhibitor) with or without ribavirin (RBV) for the treatment of HCV GT4 infection. Phylogenetic analysis of HCV NS3/4A, NS5A, and NS5B nucleotide sequences identified 7 subtypes (4a, 4b, 4c, 4d, 4f, 4g/4k, and 4o) among 132 patient samples. Subtype prevalence varied by country, and the distributions of patient birth cohort and race were significantly different across GT4 subtypes 4a, 4d, and non-4a/4d. Baseline amino acid variability was detected in NS5A across GT4 subtypes but had no impact on treatment outcome. Three patients experienced virologic failure and were infected with subtype 4d, and the predominant resistance-associated variants at the time of failure were D168V in NS3 and L28V in NS5A. Overall, high response rates were observed among patients infected with 7 HCV GT4 subtypes, with no impact of baseline variants on treatment outcome. GT4 subtype distribution in this study differed based on patient demographics and geography.

Review article: the efficacy and safety of daclatasvir in the treatment of chronic hepatitis C virus infection

BACKGROUND

The treatment of hepatitis C virus (HCV) has evolved dramatically after the introduction of direct acting anti-virals. NS5A protein plays an important role in HCV replication and is an attractive target for drug development.

AIM

To review clinical studies on the efficacy and safety of direct-acting anti-virals regimens containing daclastavir, an NS5A inhibitor, in the treatment of chronic hepatitis C.

METHODS

A Medline search was undertaken to identify relevant literature using search terms including 'daclatasvir', 'HCV treatment' and 'NS5A inhibitors'. Furthermore, we scanned abstracts presented at the recent international meetings in liver disease, viral hepatitis and infectious disease, as well as the reference lists of the review articles to identify publications not retrieved by electronic searches.

RESULTS

Daclatasvir is the first-in-class HCV NS5A inhibitor that has been demonstrated in Phase I-III trials to have a potent anti-viral effect and clinical efficacy across multiple HCV genotypes (GT). Daclastavir is generally safe and well tolerated, with a low barrier to resistance and low potential for drug-drug interaction. When Daclastavir is added to PEG-IFN/RBV platform, sustained virological response (SVR) rates are increased significantly compared with PEG-IFN/RBV alone. The all-oral combination of Daclastavir/asunaprevir (ASV; protease inhibitor) has high SVR rates against GT1b, but less activity against GT1a. Dual combination of Daclastavir/Sofosbuvir (SOF; nucleotide polymerase inhibitor) and triple combination of Daclastavir/ASV/beclabuvir (BCV; non-nucleoside polymerase inhibitor) have demonstrated >90% SVR rates in both treatment naïve and treatment-experienced patients with GT1. Furthermore, Daclastavir/SOF combination has also demonstrated up to 90% SVR rates in patients with GT3, and in those with human immunodeficiency virus coinfection, cirrhosis and post-transplant HCV recurrence with any GT. Daclastavir/ASV/BCV has primarily demonstrated near 100% SVR rates in patients with GT4.

CONCLUSION

Daclastavir-containing regimens, with or without PEG-IFN, have shown promising results in clinical trials, and present an excellent treatment option for those with chronic HCV and for multiple genotypes.

Advances in hepatitis C therapies

INTRODUCTION

The recent development of new direct acting antivirals constitutes a clinical revolution in the field of hepatitis C therapy. Different drugs with direct antiviral effects and very high potency have been developed, changing the current scenario and prognosis of hepatitis C-related liver disease. This review aims to clarify the current stage of the different antiviral strategies in patients with chronic hepatitis C infection by analyzing the specific efficacy of each combination.

AREAS COVERED

Data have been extracted from the most important published clinical trials, cumulative real-world experience reports and data from the most relevant studies presented in the last international meetings (European and American International Liver Congresses). In addition, data from the recently updated international guidelines have also been included.

EXPERT OPINION

Although there are many differences in health-care budgets among countries in the world which will surely compromise drug availability and treatment decisions, this review aims to give a general and brief recommendation to help treating physicians to choose the best option to treat hepatitis C.

Daclatasvir: a review of its use in adult patients with chronic hepatitis C virus infection

Daclatasvir (Daklinza®) is an inhibitor of hepatitis C virus (HCV) NS5A protein. It is a new, oral, direct-acting antiviral with potent pangenotypic activity. This article provides a narrative review of the efficacy and tolerability of daclatasvir in combination with other agents in the treatment of patients with chronic HCV infection and summarizes its pharmacological properties. Since daclatasvir has a different mechanism of action to other current direct-acting antivirals, it provides additive or synergistic antiviral activity when used in combination. It produces high sustained virological response rates when used in combination with peginterferon-α plus ribavirin in patients chronically infected with HCV genotypes 1-4, and provides even higher response rates when used in an interferon-free, all-oral combination with sofosbuvir, with or without ribavirin. Daclatasvir has a moderately high genetic barrier to resistance, is effective during short-term treatment over 12 weeks and has a tolerability profile similar to that of placebo. In conclusion, daclatasvir is a highly effective and well tolerated, oral, once-daily, direct-acting antiviral for use in combination therapy in adult patients chronically infected with HCV.

NS5A Sequence Heterogeneity and Mechanisms of Daclatasvir Resistance in Hepatitis C Virus Genotype 4 Infection

Background. Daclatasvir is an NS5A inhibitor approved for treatment of infection due to hepatitis C virus (HCV) genotypes (GTs) 1–4. To support daclatasvir use in HCV genotype 4 infection, we examined a diverse genotype 4–infected population for HCV genotype 4 subtype prevalence, NS5A polymorphisms at residues associated with daclatasvir resistance (positions 28, 30, 31, or 93), and their effects on daclatasvir activity in vitro and clinically.

Methods. We performed phylogenetic analysis of genotype 4 NS5A sequences from 186 clinical trial patients and 43 sequences from the European HCV database, and susceptibility analyses of NS5A polymorphisms and patient-derived NS5A sequences by using genotype 4 NS5A hybrid genotype 2a replicons.

Results. The clinical trial patients represented 14 genotype 4 subtypes; most prevalent were genotype 4a (55%) and genotype 4d (27%). Daclatasvir 50% effective concentrations for 10 patient-derived NS5A sequences representing diverse phylogenetic clusters were ≤0.080 nM. Most baseline sequences had ≥1 NS5A polymorphism at residues associated with daclatasvir resistance; however, only 3 patients (1.6%) had polymorphisms conferring ≥1000-fold daclatasvir resistance in vitro. Among 46 patients enrolled in daclatasvir trials, all 20 with baseline resistance polymorphisms achieved a sustained virologic response.

Conclusions. Circulating genotype 4 subtypes are genetically diverse. Polymorphisms conferring high-level daclatasvir resistance in vitro are uncommon before therapy, and clinical data suggest that genotype 4 subtype and baseline polymorphisms have minimal impact on responses to daclatasvir-containing regimens.

Hepatitis C treatment in the elderly: New possibilities and controversies towards interferon-free regimens

Due to the progressive aging of the hepatitis C virus (HCV) population which have acquired the infection during its maximum spread after the Second World War, the management of the elderly HCV-infected patient is emerging as a hot topic. Unfortunately, although it is recognized that the progression of HCV-related liver disease gets faster with aging, and that even extra-hepatic manifestations of HCV infection are probably worse in the elderly, till now, treatment attempts in this population have been significantly limited by the well-known contraindications and side effects of interferon (IFN). The arrival of several new anti-HCV drugs, and the possibility to combine them in safe and effective anti-viral regimens, is relighting the hope of a cure for many elderly patients who had been cut out of IFN-based treatments. However, although these new regimens will be certainly more manageable, it should be underscored that IFN-free doesn’t mean free from any contraindication or side-effect. Moreover, one issue which promises to become central is that of the possible interactions between antiviral therapy and the multiple drugs frequently assumed by elderly patients because of comorbidities. In this review, we will revise the epidemiology pointing to HCV as an infection of the elderly, the evidences that HCV harms the health of the aged patient more than that of the young one, and the available experiences of HCV treatment in the elderly with the “old” IFN-based regimens and with the newer drugs. We will conclude that the availability of IFN-free regimens should prompt us to change our mind and consider a significantly larger number of possible candidates among elderly patients, who would take significant advantage from viral eradication. Rather than the anagraphic age, drug-drug interactions and, mainly in case of economic restrictions, an evaluation of life expectancy dependent on liver disease with respect to that dependent on comorbidities, are likely to be the key issues guiding treatment indication in the next future. The sooner we will change our mind with respect to an a priori obstacle for anti-HCV treatment in the elderly, the sooner we will begin to spare many aged HCV patients from avoidable liver-related complications.

Predictive factors associated with hepatitis C antiviral therapy response

Hepatitis C virus (HCV) infection may lead to significant liver injury, and viral, environmental, host, immunologic and genetic factors may contribute to the differences in the disease expression and treatment response. In the early 2000s, dual therapy using a combination of pegylated interferon plus ribavirin (PR) became the standard of care for HCV treatment. In this PR era, predictive factors of therapy response related to virus and host have been identified. In 2010/2011, therapeutic regimens for HCV genotype 1 patients were modified, and the addition of NS3/4a protease inhibitors (boceprevir or telaprevir) to dual therapy increased the effectiveness and chances of sustained virologic response (SVR). Nevertheless, the first-generation triple therapy is associated with many adverse events, some of which are serious and associated with death, particularly in cirrhotic patients. This led to the need to identify viral and host predictive factors that might influence the SVR rate to triple therapy and avoid unnecessary exposure to these drugs. Over the past four years, hepatitis C treatment has been rapidly changing with the development of new therapies and other developments. Currently, with the more recent generations of pangenotipic antiviral therapies, there have been higher sustained virologic rates, and prognostic factors may not have the same importance and strength as before. Nonetheless, some variables may still be consistent with the low rates of non-response with regimens that include sofosbuvir, daclatasvir and ledipasvir. In this manuscript, we review the predictive factors of therapy response across the different treatment regimens over the last decade including the new antiviral drugs.

High Cure Rate With 24 Weeks of Daclatasvir-Based Quadruple Therapy in Treatment-Experienced, Null-Responder Patients With HIV/Hepatitis C Virus Genotype 1/4 Coinfection: The ANRS HC30 QUADRIH Study

BACKGROUND

Few direct anti-hepatitis C virus (HCV) agents have been studied in difficult-to-treat null responder and cirrhotic human immunodeficiency virus (HIV)-coinfected patients. Daclatasvir and asunaprevir combined with pegylated interferon/ribavirin (peg-IFN/RBV) have shown promising results in HCV-monoinfected patients.

METHODS

An open-label, single-arm, phase 2 study was conducted in HIV/HCV genotype 1/4-coinfected patients who were null responders to prior peg-IFN/RBV standard therapy and on a raltegravir-based regimen with HIV RNA <400 copies/mL. They received a 4-week lead-in phase with peg-IFN/RBV, followed by 24 weeks of asunaprevir (100 mg twice daily), daclatasvir (60 mg once daily), and peg-IFN/RBV. The primary endpoint was sustained virologic response 12 weeks after the end of treatment (SVR12) using intent-to-treat analysis.

RESULTS

Seventy-five patients were included, of whom 27 (36%) had cirrhosis. The median baseline CD4 count was 748 (interquartile range, 481-930) cells/µL. The global SVR12 rate was 96.0% (95% confidence interval [CI], 88.8%-99.2%; n = 72/75), 92.6% (95% CI, 75.7%-99.1%; n = 25/27) in cirrhotic patients, 94.6% (95% CI, 81.8%-99.3%; n = 35/37) in genotype 1 patients, and 97.4% (95% CI, 86.2%-99.9%; n = 37/38) in genotype 4 patients. Six patients (8%) stopped HCV therapy prematurely: 2 due to HCV breakthrough, 4 to adverse events (1 lung cancer, 3 infections). One patient with cirrhosis (with baseline platelet count <150 000 platelets/µL and albuminemia <35 g/L) died from multiorgan failure. Overall, 36 serious adverse events occurred in 21 (28%) patients. No HIV breakthrough was observed.

CONCLUSIONS

In HIV/HCV genotype 1/4-coinfected null responders, a 24-week regimen combining daclatasvir, asunaprevir, and peg-IFN/RBV was associated with a very high cure rate. The safety profile was acceptable, even though cirrhotic patients with low albuminemia and platelets should be monitored closely. This combination is a new option in this difficult-to-treat population.

CLINICAL TRIALS REGISTRATION

NCT01725542.

From non-A, non-B hepatitis to hepatitis C virus cure

The hepatitis C virus (HCV) was discovered in the late 1980s. Interferon (IFN)-α was proposed as an antiviral treatment for chronic hepatitis C at about the same time. Successive improvements in IFN-α-based therapy (dose finding, pegylation, addition of ribavirin) increased the rates of sustained virologic response, i.e. the rates of curing HCV infection. These rates were further improved by adding the first available direct-acting antiviral (DAA) drugs to the combination of pegylated IFN-α and ribavirin. An IFN-free era finally started in 2014, yielding rates of sustained virologic response over 90% in patients treated for 8 to 24 weeks with all-oral regimens. Major challenges however remain in implementation of these new treatment strategies, not only in low- to middle-income countries, but also in high-income countries where the price of these therapies is still prohibitive. Elimination of HCV infection through treatment in certain areas is possible but raises major public health issues.

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

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

How to optimize current therapy in hepatitis C virus genotype 1 patients. Predictors of response to interferon-based therapy with second wave direct acting antivirals

Second wave direct acting antivirals such as sofosbuvir, simeprevir and daclatasvir can be combined with pegylated interferon alpha and ribavirin (PEG-IFN/RBV) as triple therapy in patients with hepatitis C virus (HCV) infection. In patients with HCV genotype 1 (HCV-1), a PEG-IFN/RBV-based regimen with sofosbuvir is highly effective but the presence of cirrhosis and the non-CC IFNL3 genotype have been associated with a poorer response. A PEG-IFN/RBV-based regimen with simeprevir or daclatasvir is based on response-guided therapy and its efficacy depends on predictors of response to IFN. HCV-1 subtype is also a major predictor of response. In HCV-1a infected patients, the K80Q mutation in NS3 or the presence of NS5A variants at baseline are associated with poor response with simeprevir- or daclatasvir-containing regimens respectively. Thus, these regimens should be only used in HCV-1b patients with good predictors of response to IFN.

Optimal therapy in genotype 4 chronic hepatitis C: finally cured?

Optimal therapy for patients with hepatitis C virus (HCV) genotype 4 (HCV-4) infection is changing rapidly, and the possibility of a total cure is near. The standard of care has been combination pegylated interferon (PEG-IFN)-ribavirin (RBV), with modest response rates and considerable adverse events. Since the introduction of sofosbuvir (SOF), simeprevir (SIM), and daclatasvir (DCV), the duration of treatment has been significantly shortened and response rates have increased. The recommended treatment for IFN-eligible patients is PEG-IFN/RBV plus SOF, SIM or DCV. In IFN ineligible patients, the optimal regimen is a 24-week course of SOF/RBV, or a 12-week course of SOF-SIM or SOF-DCV with or without RBV. The pipeline for patients with chronic HCV is highly active. IFN-free combinations with paritaprevir-ombitasvir, SOF-ledipasvir, or DCV-asunaprevir (ASV)-beclabuvir (BMS-791325) for 12 weeks or less with close to 100% cure rates will soon become the optimal therapy.