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

Breakthroughs in hepatitis C research: from discovery to cure

In the 1970s, an unknown virus was suspected for documented cases of transfusion-associated hepatitis, a phenomenon called non-A, non-B hepatitis. In 1989, the infectious transmissible agent was identified and named hepatitis C virus (HCV) and, soon enough, the first diagnostic HCV antibody test was developed, which led to a dramatic decrease in new infections. Today, HCV infection remains a global health burden and a major cause of liver cirrhosis, hepatocellular carcinoma and liver transplantation. However, tremendous advances have been made over the decades, and HCV became the first curable, chronic viral infection. The introduction of direct antiviral agents revolutionized antiviral treatment, leading to viral eradication in more than 98% of all patients infected with HCV. This Perspective discusses the history of HCV research, which reads like a role model for successful translational research: starting from a clinical observation, specific therapeutic agents were developed, which finally were implemented in national and global elimination programmes.

Sofosbuvir-/Daclatasvir-based therapy for chronic HCV and HCV/hepatitis B virus coinfected patients in Egypt

BACKGROUND

Dramatic advances in hepatitis C virus (HCV) treatment were witnessed with the introduction of direct-acting antivirals (DAAs). Generic DAAs with remarkable efficacy and good safety profiles are currently manufactured by local pharmaceutical companies in Egypt.

METHODS

In the real-world setting, of a total of 367 patients chronically infected with HCV, 289 (277 treatment-naïve and 12 treatment-experienced) patients were enrolled. Approximately 15% of the patients were coinfected with hepatitis B virus (HBV). Patients were treated with sofosbuvir+daclatasvir with or without ribavirin for 12 or 24 wk as the standard of care. HBV DNA levels were monitored throughout the study.

RESULTS

A sustained virologic response at 12 wk (SVR12) was achieved in 98.3% of the patients. All non-responders were treatment-naïve and the response rate among treatment-experienced patients was 100.0%. Elevated α-fetoprotein and treatment with sofosbuvir+daclatasvir+ribavirin for 6 mo were predictors of non-response (OR [95% CI] = 1.06 [1.02 to 1.1] and 15.9 [1.8 to 136.2]; p<0.05, respectively). No HBV reactivation was noticed throughout the treatment and follow-up periods in HCV/HBV coinfected patients.

CONCLUSION

The present real-world findings add to the evidence for the efficacy of generic DAAs for the treatment of patients infected with HCV. HBV reactivation is unlikely to occur in those coinfected with HBV. Although liver cirrhosis affected the outcome, pretreatment liver chemistry did not seem to correlate with the results of treatment.

Treatment of hepatitis C virus infection with direct-acting antivirals plus ribavirin eliminates viral RNA from peripheral blood mononuclear cells and reduces virologic relapse in diverse hepatic parenchymal changes

Elimination of hepatitis C virus (HCV) may fail, leading to a non-response outcome because of inappropriate testing for viral RNA in peripheral blood mononuclear cells (PBMCs). Sequelae of HCV genotype 4 therapy with sofosbuvir and daclatasvir ± ribavirin were assessed in our study at the 12^th week after end of treatment (EOT) by screening for viral genomic RNA in serum and PBMCs with correlation to hepatic parenchymal changes. We recruited 102 out of 2165 patients who had received sofosbuvir/daclatasvir, either alone (n = 1573) or together with ribavirin (n = 592). Subjects were classified into three groups based on testing by single-step reverse transcription PCR: group I, HCV negative in both serum and PBMCs (n = 25); group II, HCV positive in PBMCs only (n = 52); and group III, HCV positive in both serum and PBMCs (n = 25). Groups I and II (n = 77) were selected out of 2102 (every 27^th subject), while group III (n = 25) were selected from every second or third serologic relapse (n = 63). The pre-sampling population (n = 2165) showed sustained virologic response (SVR) in 33.21%; serologic relapse in 2.91%; HCV RNA only in PBMCs (66.79%) compared to serologic relapses and potential cure (P < 0.0001); higher serologic (38 out of 63, P = 0.03210) and cellular (36 out of 52, P = 0.0002) relapses in dual therapy than in triple therapy. The post-sampling population (n = 102) showed more HCV relapses in dual (50 out of 60) than in triple (27 out of 42) therapy (P = 0.0351); increased HCV antisense RNA strand in relapses compared to positive-sense strands alone (P < 0.001); and significant SVR events in undetectable (15 out of 31) compared to early (10 out of 55, P = 0.0058) and cirrhotic liver tissue changes (0 out of 16, P = 0.0006). In summary, HCV treatment with sofosbuvir/daclatasvir is followed by higher rates of serologic and intracellular viral RNA relapse than treatment with sofosbuvir/daclatasvir plus ribavirin. Cellular and serum viral RNA relapses are accompanied by HCV-induced hepatic pathology. An increased SVR with no detectable liver tissue changes was observed after triple therapy due to elimination of HCV RNA from PBMCs.

Sofosbuvir and daclatasvir compared with standard of care in the treatment of patients admitted to hospital with moderate or severe coronavirus infection (COVID-19): a randomized controlled trial

Background

Currently no effective antiviral therapy has been found to treat COVID-19. The aim of this trial was to assess if the addition of sofosbuvir and daclatasvir improved clinical outcomes in patients with moderate or severe COVID-19.

Methods

This was an open-label, multicentre, randomized controlled clinical trial in adults with moderate or severe COVID-19 admitted to four university hospitals in Iran. Patients were randomized into a treatment arm receiving sofosbuvir and daclatasvir plus standard care, or a control arm receiving standard care alone. The primary endpoint was clinical recovery within 14 days of treatment. The study is registered with IRCT.ir under registration number IRCT20200128046294N2.

Results

Between 26 March and 26 April 2020, 66 patients were recruited and allocated to either the treatment arm (n = 33) or the control arm (n = 33). Clinical recovery within 14 days was achieved by 29/33 (88%) in the treatment arm and 22/33 (67%) in the control arm (P = 0.076). The treatment arm had a significantly shorter median duration of hospitalization [6 days (IQR 4–8)] than the control group [8 days (IQR 5–13)]; P = 0.029. Cumulative incidence of hospital discharge was significantly higher in the treatment arm versus the control (Gray’s P = 0.041). Three patients died in the treatment arm and five in the control arm. No serious adverse events were reported.

Conclusions

The addition of sofosbuvir and daclatasvir to standard care significantly reduced the duration of hospital stay compared with standard care alone. Although fewer deaths were observed in the treatment arm, this was not statistically significant. Conducting larger scale trials seems prudent.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Efficacy and Safety of 12-week Interferon-based Danoprevir Regimen in Patients with Genotype 1 Chronic Hepatitis C

Background and Aims: Genotype (GT) 1 remains the predominant hepatitis c virus (HCV) GT in Chinese patients. Over 80% of those Chinese patients harbor the interferon-sensitive CC allele of IFNL4rs12979860, which is favorable for interferon-based treatment regimens. This phase III clinical trial aimed to evaluate the efficacy and safety of the ritonavir-boosted danoprevir plus pegylated-interferon α-2a and ribavirin regimen for 12 weeks in treatment-naïve mainland Chinese patients infected with HCV GT1 without cirrhosis. Methods: One hundred and forty-one treatment-naïve, non-cirrhotic HCV GT1 Chinese patients (age ≥18 years) were enrolled for this single-arm, multicenter, phase III MANASA study (NCT03020082). Patients received a combination of ritonavir-boosted danoprevir (100 mg/100 mg) twice a day plus subcutaneous injection of weekly pegylated-interferon α-2a (180 μg) and oral ribavirin (1000/1200 mg/day body weight <75/≥75 kg) for 12 weeks. The primary end-point was sustained virologic response rate at 12 weeks after the end of treatment. The secondary end-points were safety outcomes, tolerability, virologic response over time and relapse rate. Results: All enrolled patients were HCV GT1-infected, and most among them (97.9%, 123/141) had the HCV GT1b subtype. Single-nucleotide polymorphism test showed that the majority of patients were of the IFNL4 rs12979860 CC genotype (87.2%, 123/141). Overall, 140 patients completed the 12-week treatment, and 97.1% (136/140) patients achieved sustained virologic response at 12 weeks (per protocol population group, 95% confidence interval: 92.9-99.2%). Only drug-related serious adverse event occurred. Most of the adverse events were grade 1 and grade 2 alanine aminotransferase elevation or liver dysfunction. One patient discontinued treatment because of severe head injury in a car accident. Conclusions: The triple regimen of ritonavir-boosted danoprevir plus pegylated-interferon α-2a and ribavirin produced a sustained virologic response rate of 97.1% after 12 weeks treatment in noncirrhotic HCV GT1-infected Chinese patients, and was safe and well tolerated. Trial Registration Clinical-Trials.gov Identifier: NCT03020082.

Deep-sequencing study of HCV G4a resistance-associated substitutions in Egyptian patients failing DAA treatment

PURPOSE

 To study resistance-associated substitutions using next-generation sequencing in Egyptian hepatitis C virus-infected patients failing direct-acting antiviral treatment.

METHODS

 The current study describes three cases of treatment failure in patients referred to Zagazig Viral Hepatitis Treatment Center (ZVHTC), Sharkia Governorate, Egypt. RAS were identified and characterized using deep sequencing. The first patient had breakthrough while receiving a daclatasvir (DCV)+sofosbuvir (SOF) regimen, patient 2 relapsed after treatment with DCV+SOF+ribavirin (RBV), and patient 3 relapsed after DCV+SOF therapy. A serum sample was collected from each patient at failure and sent to Vall d'Hebron Research Institute at Hospital Universitari Vall d'Hebron in Barcelona (Spain) for deep-sequencing study to identify and characterize the RAS present in the samples.

RESULTS

 The following were identified: L28M, L30S and L28M+L30S in patient 1, L30R in patient 2, and R155C, D168E, L28M, L30H, L30S, L28M+L30H, and L28M+L30S in patient 3.

CONCLUSION

To the best of our knowledge, this is the first report from Egypt of patients failing DAA-based therapy, describing the associated RAS. This information will be of help to understand the natural history of HCV in Egyptian patients and guide the proper choice of retreatment protocols.

New Direct-Acting Antivirals for the Treatment of Patients With Hepatitis C Virus Infection: A Systematic Review of Randomized Controlled Trials

BACKGROUND

New direct-acting antiviral agents (DAAs) approved for the treatment of patients infected by Hepatitis C virus (HCV) are well tolerated and increase sustained virological response (SVR) rate. We summarize current evidence on the efficacy and safety from comparative randomized controlled trials (RCTs) of DAAs.

METHODS

We systematically searched MEDLINE, Embase, Scopus, CENTRAL, and Lilacs as well as a list of reference literature. We included RCTs comparing DAAs with placebo or active control and reporting response rates and adverse events according to antiviral regimens. Risk ratios (RRs) were pooled as appropriate. We assessed the risk of bias of included studies and graded the quality of evidence according to the GRADE method.

RESULTS

We included 28 RCTs, enrolling more than 7000 patients. The quality of evidence was generally low. Twelve-week treatment with DAAs in naïve patients significantly increased SVR12 and SVR24 compared with placebo (RR 1.4, 95% CI 1.3-1.6; RR 1.5, 95% CI 1.4-1.6, respectively). This means that for every 1000 patients, 240 or 260 more patients experienced SVR12 or SVR24 if treated with any DAAs. We could not find RCTs assessing progression of liver disease or development of hepatocellular carcinoma. DAAs were not associated with higher incidence of serious adverse events or discontinuation due to adverse events.

CONCLUSIONS

This systematic review confirms that new DAAs are more effective in inducing SVR than placebo. Outside clinical trials, in real word, HCV cure with DAA regimens occurs in less than 90% of patients, so further comparative evaluations are needed to establish their long-term effects.

Evolution of efficacious pangenotypic hepatitis C virus therapies

Hepatitis C compromises the quality of life of more than 350 million individuals worldwide. Over the last decade, therapeutic regimens for treating hepatitis C virus (HCV) infections have undergone rapid advancements. Initially, structure-based drug design was used to develop molecules that inhibit viral enzymes. Subsequently, establishment of cell-based replicon systems enabled investigations into various stages of HCV life cycle including its entry, replication, translation, and assembly, as well as role of host proteins. Collectively, these approaches have facilitated identification of important molecules that are deemed essential for HCV life cycle. The expanded set of putative virus and host-encoded targets has brought us one step closer to developing robust strategies for efficacious, pangenotypic, and well-tolerated medicines against HCV. Herein, we provide an overview of the development of various classes of virus and host-directed therapies that are currently in use along with others that are undergoing clinical evaluation.

Characterization of demographics and NS5A genetic diversity for hepatitis C virus genotype 4-infected patients with or without cirrhosis treated with ombitasvir/paritaprevir/ritonavir

Hepatitis C virus (HCV) genotype 4 (GT4) is genetically diverse with 17 confirmed and 4 provisional subtypes. In this report, HCV GT4-infected patient samples from Phase 2/3 clinical studies were analysed to characterize global demographics and genetic diversity of GT4 infection among patients treated with ombitasvir (OBV, NS5A inhibitor) plus paritaprevir/r (NS3/4A inhibitor codosed with ritonavir). Among 17 subtypes isolated from GT4-infected patients in the PEARL-I and AGATE-I studies, subtype prevalence by country of enrolment and country of origin suggested that subtypes 4a and 4d were likely circulating in Europe, while heterogeneous GT4 subtypes and a portion of GT4a detected in European and North American countries were likely due to immigration of HCV-infected patients from Africa. The distributions of birth cohort and race were also significantly different across GT4 subtypes 4a, 4d, and non-4a/4d. In addition, phylogenetic analyses of NS5A sequences revealed clustering within subtype 4a which segregated by the patient-reported country of origin and the presence of the L30R/S polymorphism. HCV NS5A sequences derived from GT4a-infected patients who originated from Europe and the United States clustered separately from sequences derived from patients who originated from Egypt, suggesting that genetically distinct strains of subtype 4a may be circulating globally. Finally, NS5A baseline polymorphisms were frequently detected at amino acid positions of interest for the inhibitor-class and OBV retained activity against 37 of 39 NS5A GT4 clinical isolates, with no impact on treatment outcome in the PEARL-I and AGATE-I studies.

Long-term follow-up of clinical trial patients treated for chronic HCV infection with daclatasvir-based regimens

BACKGROUND & AIMS

Daclatasvir has achieved high sustained virologic response (SVR) rates in diverse hepatitis C virus (HCV) populations. This study evaluated the long-term efficacy and safety of daclatasvir-based regimens administered during clinical studies.

METHODS

Patients enrolled within 6 months of parent study completion or protocol availability at the study sites. The primary objective was durability of SVR at follow-up Week 12 (SVR12). Secondary objectives included analysing HCV sequences in non-responders or responders who relapsed, and characterization of liver disease progression.

RESULTS

Between 24 February 2012 and 17 July 2015, this study enrolled and began following 1503 recipients of daclatasvir-based regimens (follow-up cut-off, 13 October 2015); 60% were male, 18% aged ≥65 years, 87% had genotype-1a (42%) or -1b (45%) infection, and 18% had cirrhosis. Median follow-up from parent study follow-up Week 12 was 111 (range, 11-246) weeks. 1329/1489 evaluable patients were SVR12 responders; 1316/1329 maintained SVR until their latest visit. Twelve responders relapsed by (n = 9) or after (n = 3) parent study follow-up Week 24; one was reinfected. Relapse occurred in 3/842 (0.4%) and 9/487 (2%) responders treated with interferon-free or interferon-containing regimens, respectively. Hepatic disease progression and new hepatocellular carcinoma were diagnosed in 15 and 23 patients, respectively. Among non-responders, emergent non-structural protein-5A (NS5A) and -3 (NS3) substitutions were replaced by wild-type sequences in 27/157 (17%) and 35/47 (74%) patients, respectively.

CONCLUSIONS

SVR12 was durable in 99% of recipients of daclatasvir-based regimens. Hepatic disease progression and new hepatocellular carcinoma were infrequent. Emergent NS5A substitutions persisted longer than NS3 substitutions among non-responders.

Eliminating hepatitis C within low-income countries - The need to cure genotypes 4, 5, 6

Around 70 to 100 million people are chronically infected with HCV worldwide. HCV antiviral drug development has revolutionised the treatment of HCV, with several direct-acting antiviral agents offering patients the chance of cure after only 8-12 weeks of treatment. Drug development was initially focussed on HCV genotype 1 (GT1) infection, since this was the most prevalent worldwide, although clinical trials included all genotypes prevalent in the US and Europe. Because the earliest in vitro assays utilised the GT1b and 2 replicons, the initial classes of direct-acting antivirals (protease inhibitors, non-nucleotide polymerase inhibitors) were GT1-specific, albeit they had an effect on other less prevalent genotypes. Epidemiological data has shown the regional importance of other HCV genotypes. More than 50% of all HCV infections around the globe are not with GT1. The prevalence of HCV genotype 4 (GT4), 5 (GT5), and 6 (GT6) is increasing in North America and Europe due to migration from the Middle East, Africa and South-East Asia. With the successful development of the multi and pan-genotypic non-structural protein 5A inhibitors, second generation protease inhibitors and nucleotide non-structural protein 5B inhibitors comes a unique opportunity to achieve global HCV elimination. The goal of this review is to summarise the available information pertaining to GT4, GT5 and GT6, with a specific focus on direct-acting antiviral agents.

Protease inhibitor therapy for hepatitis C virus-infection

INTRODUCTION

The hepatitis C virus (HCV) has affected an estimated of 80 million individuals worldwide and is a strain on public health. Around 25-30% of patients in Europe and the US who are infected with HIV are coinfected with HCV. Prior to 2013, treatment modalities containing an NS3/4A protease inhibitor in combination with pegylated interferon and ribavirin improved sustained virological response (SVR) rates. However, rates of severe side effects were high. Nowadays, oral direct-acting antiviral (DAA) combination therapy offers excellent treatment efficacy, safety and tolerability.

AREAS COVERED

This review focuses on the current literature and clinical evidence and their impact regarding NS3/4A protease inhibitors. The pitfalls encountered in treating HIV- and HBV-coinfected patients are also discussed.

EXPERT OPINION

In the era of DAA treatment, third-generation pan-genotypic NS3/4A protease inhibitors (mainly glecaprevir and voxilaprevir) show high antiviral activity and a genetic resistance barrier with cure rates of over 95% when combined with an NS5A inhibitor, irrespective of baseline resistance associated variants (RASs) being present. These new key components of DAA combination therapy are impressive options to eradicate HCV in the so-called difficult-to-treat population (e.g. compensated cirrhosis, end-stage renal disease and patients who failed previous DAA treatment).

Efficacy of daclatasvir-based quadruple therapy in nonresponder patients infected by hepatitis C virus genotype 4: the ANRS HC32 QUATTRO study

BACKGROUND

A few direct antiviral agents have been studied in difficult-to-treat patients infected by hepatitis C virus (HCV) genotype 4 (GT4). The efficacy of daclatasvir (DCV), asunaprevir (ASV), pegylated interferon and ribavirin (Peg-IFN/RBV) association was investigated in these patients.

PATIENTS AND METHODS

This open-label, single-arm, phase 2 study was conducted in HCV GT4 patients who were null or partial responders to Peg-IFN/RBV. Patients received 24 weeks of DCV (60 mg, once daily), ASV (100 mg, twice daily) and Peg-IFN/RBV. The primary endpoint was sustained virologic response at post-treatment week 12 [sustained virologic response (SVR)12].

RESULTS

Sixty patients were included; 45 (75%) were previous null responders and 27 (45%) had cirrhosis. The most frequent subtypes were GT4a (48%) and GT4d (27%) with 25% of the patients being infected with other subtypes such as 4c, 4r, 4f, 4k, 4j and 4q. The global SVR12 was 95% (90% confidence interval: 90.4-99.6) and 96.3% (90% confidence interval: 87.5-99.5) in cirrhotic patients. All patients achieving SVR12 also achieved SVR24. Previous Peg-IFN/RBV response, IL28b genotype, cirrhosis status or GT4 subtypes did not influence SVR12 rates. Serious adverse events occurred in 13% of the patients, four being cirrhotic and four noncirrhotic. Three (5%) patients stopped HCV therapy prematurely: one because of virologic breakthrough and two because of serious adverse events. Grade 3/4 laboratory abnormalities included leukopenia (33%), neutropenia (27%), thrombocytopenia (4%) and transaminases increase (2%).

CONCLUSION

Association of DCV plus ASV and peg-IFN/RBV for 24 weeks demonstrated a high rate of SVR12 in HCV GT4-infected prior nonresponders, independently of the cirrhotic status or the GT4 subtype. The safety profile was acceptable, even in cirrhotic patients.

Generic daclatasvir plus sofosbuvir, with or without ribavirin, in treatment of chronic hepatitis C: real-world results from 18 378 patients in Egypt

BACKGROUND

Treatment of chronic hepatitis C using combination of sofosbuvir (SOF) and daclatasvir (DCV) was used in several clinical trials and multicentre studies, which were somewhat limited to genotypes 1-3. The national program in Egypt is using SOF-DCV combination for large scale treatment.

AIM

To assess the efficacy and safety of combined SOF-DCV in treating patients with HCV-G4 in a real-world setting.

METHODS

Data and outcome of chronic HCV patients who were treated for 12 weeks with generic medications: DCV 60 mg plus SOF 400 mg ± ribavirin (RBV) within the national hepatitis C treatment program in Egypt are presented. Treatment-naïve patients without cirrhosis were treated without RBV, and those who had cirrhosis or were treatment-experienced (interferon experienced or SOF experienced) received RBV. Efficacy and safety were assessed, and baseline factors associated with sustained virological response at post-treatment week 12 (SVR12) were explored.

RESULTS

During the first 2 months of the programme, 18 378 patients with HCV-G4 started treatment with SOF-DCV with or without RBV. Overall, 95.1% achieved SVR12 (95.4% among patients treated without RBV and 94.7% for patients treated with RBV, P = .32). Treatment was prematurely discontinued in only 1.5% of patients. The most common events leading to discontinuation were patient withdrawal (n = 76) and pregnancy (n = 5). Five deaths occurred within this group.

CONCLUSIONS

Real-world experience of generic SOF-DCV in patients with chronic HCV-G4 proved to be safe and associated with a high SVR12 rate, in patients with different stages of fibrosis.

Pegylated interferon alpha 2a for the treatment of hepatitis C virus infection

INTRODUCTION

Treatments for hepatitis C virus (HCV) infection have advanced rapidly in the last decade. Pegylated interferon alpha 2a (PEG-IFN alpha 2a) alone, in combination with ribavirin and with or without direct acting antivirals (DAAs) is modestly effective in the treatment of chronic HCV infection. Areas covered: The review describes the chemistry, pharmacokinetic and pharmacodynamic properties, clinical efficacy, safety and drug-drug interaction profiles of PEG-IFN alpha 2a. Expert opinion: Despite the availability of DAAs and its formidable toxicity profile, PEG-IFN alpha 2a retains a role for the treatment of acute HCV and chronic HCV infection in resource limited settings and for end-stage renal disease patients and others who cannot access DAAs or are DAA-ineligible. Knowledge of pharmacogenetic profiles which favor successful treatment outcomes with IFN-based therapies may allow for selection of best candidates for the regimen.

Protease inhibitors for the treatment of hepatitis C virus infection

The hepatitis C virus (HCV) has affected an estimate of 80 million individuals worldwide and is a strain of public health. Around 25-30% of patients in Europe and the US infected with HIV are coinfected with HCV. Despite treatment modalities containing a NS3/4A protease inhibitor in combination with pegylated interferon and ribavirin prior to 2013 improved SVR rates, the amount of severe side effects was high. Nowadays, oral direct-acting antivirals (DAAs) combination therapy offers excellent treatment efficacy, safety and tolerability. This review focuses on current literature and clinical evidence and their impact regarding NS3/4A protease inhibitors. In addition, pitfalls in treatment from HIV- and HBV-coinfected patients will also be discussed. In the era of DAA treatment, the third-generation pan-genotypic NS3/4A protease inhibitors (mainly grazoprevir, glecaprevir and voxilaprevir) show a high antiviral activity and genetic resistance barrier with cure rates of over 95% when combined with an NS5A inhibitor, irrespectively of baseline resistance associated variants (RASs) being present. These new key components of DAA combination therapy are impressive options to eradicate HCV in the so called difficult-to-treat population (e.g. compensated cirrhosis, end-stage renal disease and patients who failed previous DAA treatment).

Prevalence of hepatitis C virus-resistant association substitutions to direct-acting antiviral agents in treatment-naïve hepatitis C genotype 1b-infected patients in western China

Background

Direct-acting antivirals (DAAs) against hepatitis C virus (HCV) are potent and highly efficacious. However, resistance-associated substitutions (RASs) relevant to DAAs can impair treatment effectiveness even at baseline. Moreover, the prevalence of baseline RASs in HCV genotype 1b-infected patients in western China is still unclear.

Materials and methods

Direct sequencing of the HCV NS3, NS5A, and NS5B regions was performed in baseline serum samples of 70 DAAs treatment-naïve HCV 1b-infected patients in western China. The sequences were analyzed with MEGA version 5.05 software. Evolutionary patterns of RASs and amino-acid covariance patterns in the NS3, NS5A, and NS5B genes were analyzed by MEGA and Cytoscape (version 3.2.1), respectively.

Results

The presence of at least one RAS in the NS3 region (C16S, T54S, Q80R/L, A87T, R117H, S122G, V132I, V170I) was observed in 85.48% (53 of 62) of patients, RASs in the NS5A region (L28M, R30Q, Q54H, P58S/T, Q62H/R, Y93H) were observed in 42.42% (28 of 66) of patients, and RASs in the NS5B region (N142S, A300T, C316N, A338V, S365A, L392I, M414L, I424V, A442T, V499A, S556G) were observed in 100% (44 of 44) of patients. Evolutionary patterns of RASs and amino-acid covariance patterns for the NS3, NS5A, and NS5B genes are reported.

Conclusion

The prevalence of RASs relevant to DAAs detected in the NS3, NS5A, and NS5B regions of HCV 1b from DAA treatment-naïve patients is high. Therefore, more attention should be paid to RASs associated with DAAs in the upcoming DAA-treatment era in China.

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.

Hepatitis C treatment from "response-guided" to "resource-guided" therapy in the transition era from interferon-containing to interferon-free regimens

Peginterferon/ribavirin has been the standard-of-care for chronic hepatitis C virus (HCV) infections: 48 weeks for genotype 1 or 4 (HCV-1/4) and 24 weeks for HCV-2/3. Response-guided therapy recommended shorter 24- and 16-week regimens for HCV-1 with lower baseline viral loads (< 400 000-800 000 IU/mL) and rapid virological response (RVR, undetectable HCV RNA at week 4) and HCV-2/3 with RVR, respectively; and extending to 72 and 48 weeks for HCV-1 slower responders and HCV-2 non-RVR patients, respectively, to improve the efficacy. The progress of directly acting antivirals (DAA), moving from interferon-containing regimens in 2011 to interferon-free regimens in 2013, has greatly improved the treatment success. Interferon-containing regimens include boceprevir or telaprevir or simeprevir or daclatasvir plus peginterferon/ribavirin, 24-48 weeks, for HCV-1 or 4. However, adding these DAA has no benefit for HCV-1 with lower baseline viral loads/RVR. Instead, 12-week sofosbuvir plus peginterferon/ribavirin attained sustained virological response rates of > 90% for HCV-1/3-6. Interferon-free regimens include two main categories: NS5B nucleotide inhibitor (sofosbuvir)-based regimens and NS3/4A inhibitor/NS5A inhibitor-based regimens (daclatasvir/asunaprevir, paritaprevir/r/ombitasvir/dasabuvir and grazoprevir/elbasvir). About 8-24 weeks interferon-free regimens could achieve sustained virological response rates of 82-99% for corresponding HCV genotypes. Although the newly DAA interferon-free regimens have high efficacy and safety, the huge budget impact increases the treatment barriers. The current recommendation should, therefore, base on the availability, indication, and cost-effectiveness in the transition era of DAA. Based on the concept of "resource-guided therapy," peginterferon/ribavirin might be applied for easy-to-treat interferon-eligible patients in resource-constrained areas. Prioritizing patients for interferon-free regimens according to "time-degenerative factors" (age and fibrosis) is justified before the regimens becoming available and affordable.

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.

Safety and efficacy of direct-acting antivirals for the treatment of chronic hepatitis C in a real-world population aged 65 years and older

The availability of direct-acting antiviral agents (DAA) regimens has expanded the pool of patients eligible for treatment. However, data on the virologic response and tolerability of DAAs in elderly patients are lacking. We evaluated the efficacy and safety of DAAs in patients with advanced fibrosis/cirrhosis in real-life practice with the focus on those aged ≥65 years. Between January and December 2015, all consecutive patients with HCV-related advanced fibrosis/cirrhosis treated with DAA at eleven tertiary referral centres in Emilia Romagna (Italy) were enrolled. Regimen choice was based on viral genotype and stage of disease, according to guidelines. The primary end point was sustained virologic response 12 weeks after the end of treatment (SVR12). Overall, 282 of 556 (50.7%) patients evaluated were elderly, most of them with cirrhosis. Antiviral therapy was stopped prematurely in four (1.4%) patients. Two patients, both with cirrhosis, died during treatment due to worsening of liver/renal function. SVR12 was achieved by 94.7% and was comparable to that obtained in patients aged <65 (P=.074). Similar data were also reported in subgroup of patients aged ≥75 years. All patients with advanced fibrosis achieved virologic response. SVR12 was 80.8% in Child-Pugh-Turcotte (CTP)-B cirrhosis and 95.4% in CTP-A (P=.013). According to genotype, the SVR12 was achieved in 172 of 181 (95%) with genotype 1b cirrhosis and in 44 of 48 (91.7%) with genotype 2 cirrhosis. In conclusions, in a real-world setting, DAAs are safe and effective in elderly patients with HCV-related advanced fibrosis/cirrhosis, but SVR12 is lower with worsening CTP class.

Real-world challenges for hepatitis C virus medications: a critical overview

From 2010, the landscape of hepatitis C therapeutics has been changed rapidly, and today we are standing at a cusp of a pharmacological revolution where highly effective and interferon (IFN)-free direct acting antivirals (DAAs) are already on the market. Such treatment paradigms attain 90-95% sustained virologic response (SVR; undetectable viral load at week 12 or 24 at the end of therapy) rates in treated individuals compared to 50-70% with treatment completion of dual-therapy-pegylated interferon (PEG-IFN) and ribavirin (RBV). As the major goal now for the hepatologists, clinicians, physicians, and health care workers is likely to eradicate hepatitis C infection in parallel to treatment, the demand is for a one-size-fits-all pill that could be prescribed beyond the limitations of hepatitis C genotype, viral load, previous treatment history, advanced hepatic manifestations (fibrosis, cirrhosis) and antiviral drug resistance. Although the new treatment strategies have shown high cure rates in clinical trials, such treatment paradigms are posing dilemmas too in real-world clinical practice. Therapy cost, treatment access to low and middle-income countries, treatment-emergent adverse events, lack of effective viral screening and disease progression simulation models are potential challenges in this prospect. This review article deeply overviews the challenges encountered while surmounting the burden of hepatitis C around the world.

Hepatitis C Virus-Genotype 3: Update on Current and Emergent Therapeutic Interventions

PURPOSE OF REVIEW

Direct-acting antiviral agents (DAAs) have markedly improved the prognosis of hepatitis C virus (HCV)-genotype 3 (GT3), a highly prevalent infection worldwide. However, in patients with hepatic fibrosis, cirrhosis, or hepatocellular carcinoma (HCC), GT3 infection presents a treatment challenge compared with other genotypes. The dependence of the HCV life cycle on host lipid metabolism suggests the possible utility of targeting host cellular factors for combination anti-HCV therapy. We discuss current and emergent DAA regimens for HCV-GT3 treatment. We then summarize recent research findings on the reliance of HCV entry, replication, and virion assembly on host lipid metabolism.

RECENT FINDINGS

Current HCV treatment guidelines recommend the use of daclatasvir plus sofosbuvir (DCV/SOF) or sofosbuvir plus velpatasvir (SOF/VEL) for the management of GT3 based upon clinical efficacy [≥88% overall sustained virological response (SVR)] and tolerability. Potential future DAA options, such as SOF/VEL co-formulated with GS-9857, also look promising in treating cirrhotic GT3 patients. However, HCV resistance to DAAs will likely continue to impact the therapeutic efficacy of interferon-free treatment regimens. Disruption of HCV entry by targeting required host cellular receptors shows potential in minimizing HCV resistance and broadening therapeutic options for certain subpopulations of GT3 patients. The use of cholesterol biosynthesis and transport inhibitors may also improve health outcomes for GT3 patients when used synergistically with DAAs. Due to the morbidity and mortality associated with HCV-GT3 infection compared to other genotypes, efforts should be made to address current limitations in the therapeutic prevention and management of HCV-GT3 infection.

Real life Egyptian experience of efficacy and safety of Simeprevir/Sofosbuvir therapy in 6211 chronic HCV genotype IV infected patients

BACKGROUND & AIMS

Major changes have emerged during the last few years in the therapy of chronic HCV. Several direct acting antiviral agents have been developed showing potent activity with higher rates of sustained virological response, even in difficult-to-treat patients. This study explores real life experience concerning efficacy, safety and possible predictors of response for the first cohort of Egyptian patients with chronic HCV genotype IV treated with Sofosbuvir/Simprevir combination therapy.

METHODS

This real life study recruited the first (6211) chronic HCV genotype IV Egyptian patients, who received antiviral therapy in viral hepatitis specialized treatment centres affiliated to the National committee for control of viral hepatitis. All enrolled patients received 12 weeks course of daily combination of sofosbuvir (400 mg) and simeprevir (150 mg). Patients were closely monitored for treatment safety and efficacy.

RESULTS

Overall sustained virological response 12 rate was 94.0% while the end of treatment response rate was 97.6%. sustained virological response 12 rates in easy and difficult-to-treat groups were 96% and 93% respectively. Univariate and multivariate logistic regression analysis revealed significant association of low albumin (<3.5), cirrhosis and Fib-4 score (>3.25) with treatment failure. Fatal adverse events occurred in 23/6211 cases (0.37%) due to liver cell failure adverse events or SAEs leading to treatment discontinuation occurred in 97 patients (1.6%).

CONCLUSION

Sofosbuvir/Simeprevir combination is an effective and well tolerated regimen for patients with chronic HCV genotype IV.

Hepatitis C treatment: where are we now?

Chronic hepatitis C infection affects millions of people worldwide and confers significant morbidity and mortality. Effective treatment is needed to prevent disease progression and associated complications. Previous treatment options were limited to interferon and ribavirin (RBV) regimens, which gave low cure rates and were associated with unpleasant side effects. The era of direct-acting antiviral (DAA) therapies began with the development of first-generation NS3/4A protease inhibitors in 2011. They vastly improved outcomes for patients, particularly those with genotype 1 infection, the most prevalent genotype globally. Since then, a multitude of DAAs have been licensed for use, and outcomes for patients have improved further, with fewer side effects and cure rates approaching 100%. Recent regimens are interferon-free, and in many cases, RBV-free, and involve a combination of DAA agents. This review summarizes the treatment options currently available and discusses potential barriers that may delay the global eradication of hepatitis C.

Efficacy and safety of daclatasvir plus pegylated-interferon alfa 2a and ribavirin in previously untreated HCV subjects coinfected with HIV and HCV genotype-1: a Phase III, open-label study

BACKGROUND

Daclatasvir (DCV) is a potent, pangenotypic, hepatitis C virus (HCV) non-structural protein 5A inhibitor with low potential for drug interactions with antiretroviral therapy (ART). We evaluated the safety and efficacy of DCV plus peginterferon alfa-2a/ribavirin (PegIFN/RBV) in HIV-1/HCV genotype-1-coinfected patients.

METHODS

AI444043 (NCT01471574), an open-label, Phase III, single-arm, response-guided treatment (RGT) study included 301 patients. They received DCV doses of 30, 60 or 90 mg once daily (depending on concomitant ART), plus weight-based RBV (<75 kg, 1000 mg/day; or ≥75 kg, 1200 mg/day), and once-weekly PegIFN 180 μg, for 24 weeks. If required by RGT, PegIFN/RBV without DCV was extended for an additional 24 weeks of therapy. The primary endpoint was the proportion of patients with sustained virologic response at post-treatment Week 12 (SVR12).

RESULTS

Overall, 224 (74%) patients achieved SVR12 and the lower bound of the 95% confidence interval was higher than the historic SVR rate with PegIFN/RBV alone (70 vs. 29%). Most common adverse events (AEs) were fatigue, neutropenia, anemia, asthenia and headache. On-treatment serious AEs occurred in 24/301 (8%) patients; 18/301 (6%) discontinued treatment due to AE.

CONCLUSIONS

DCV + PegIFN/RBV led to sustained HCV virologic response in the majority of HIV-1-HCV-coinfected patients, regardless of concomitant ART. HIV control was not compromised and no new safety signals were identified. This study supports DCV use in HIV-1-HCV-coinfected patients, while allowing the vast majority of patients to remain on their existing ART regimen.

Small-molecule inhibitors of hepatitis C virus (HCV) non-structural protein 5A (NS5A): a patent review (2010-2015)

INTRODUCTION

Non-structural 5A (NS5A) protein has achieved a considerable attention as an attractive target for the treatment of hepatitis C (HCV). A number of novel NS5A inhibitors have been reported to date. Several drugs having favorable ADME properties and mild side effects were launched into the pharmaceutical market. For instance, daclatasvir was launched in 2014, elbasvir is currently undergoing registration, ledipasvir was launched in 2014 as a fixed-dose combination with sofosbuvir (NS5B inhibitor). Areas covered: Thomson integrity database and SciFinder database were used as a valuable source to collect the patents on small-molecule NS5A inhibitors. All the structures were ranked by the date of priority. Patent holder and antiviral activity for each scaffold claimed were summarized and presented in a convenient manner. A particular focus was placed on the best-in-class bis-pyrrolidine-containing NS5A inhibitors. Expert opinion: Several first generation NS5A inhibitors have recently progressed into advanced clinical trials and showed superior efficacy in reducing viral load in infected subjects. Therapy schemes of using these agents in combination with other established antiviral drugs with complementary mechanisms of action can address the emergence of resistance and poor therapeutic outcome frequently attributed to antiviral drugs.

Efficacy and Safety of Daclatasvir in Hepatitis C: An Overview

Hepatitis C virus (HCV) infection is a growing public health concern, with 184 million people infected worldwide. During the past decade, interferon has been the backbone of HCV treatment, even though it remains far from ideal. The latest development of the new direct antivirals has drastically changed the treatment approach for chronic hepatitis C (CHC). Inhibitors of the HCV NS5A region have garnered remarkable interest among treating physicians, due to their high potency and favourable safety profile. In particular, treatment with daclatasvir (DCV) has yielded high rates of vriologic response in patients infected with genotype (Gt) 1 and Gt 3, when used in combination with other antivirals of a different class, such as sofosbuvir. Although few data are available for DCV treatment of the other Gts, the results in patients with Gt 2 and Gt 4 infection appear promising, as do those for unique patient populations. NS5A-resistant viral variants can pre-exist or emerge after treatment failure for the HCV NS5A inhibitors. Nonetheless, DCV-resistant viral variants continue to be sensitive to interferon and other classes of antivirals such as NS3/4A and NS5B inhibitors. Herein, we aimed to provide an overview of the current knowledge about DCV in the treatment of CHC.

Network meta-analysis of first- and second-generation protease inhibitors for chronic hepatitis C genotype 1: efficacy based on RVR and SVR 24

PURPOSE

This study aimed to compare the efficacy among direct-acting antiviral agents (first and second-generation direct-acting antiviral agents (DAAs)) with placebo and with standard dual therapy (pegylated interferon + ribavirin (Peg-IFN + RBV)) in terms of rapid virologic response (RVR) and sustained virologic response (SVR) in chronic hepatitis C genotype 1 treatment.

METHODS

We performed a systematic review of randomized controlled trials (RCTs) in MEDLINE, International Pharmaceutical Abstracts, Cochrane Library, SCIELO, and Scopus and conducted a network meta-analysis to compare the efficacy of boceprevir (BOC), daclatasvir (DCV), grazoprevir, simeprevir (SMV) and telaprevir (TVR), in treatment-naive and treatment-experienced patients.

RESULTS

Sixteen studies encompassing 7171 patients were analysed. Associations between DAAs therapies (IFN-free regimens) could not be addressed since no common comparator was found in the RCTs among these associations and the other agents included in the present analysis. All agents were more efficacious than placebo or Peg-IFN + RBV in terms of RVR, while only BOC and SMV showed statistically significant superiority for the SVR outcome when compared to placebo or standard dual therapy. No significant differences between the DAAs were observed. The analysis prioritized treatment with DCV for both efficacy outcomes. Node-splitting analysis showed that our networks are robust (p > 0.05).

CONCLUSIONS

The superiority of DAAs over placebo or standard dual therapy with Peg-IFN + RBV was confirmed, indicating the greater efficacy of DCV. This study is the first network meta-analysis that included RVR as an outcome in the evaluation of these agents via indirect comparison. Further investigation should be carried out addressing safety and tolerability outcomes.

Daclatasvir for the Treatment of Chronic Hepatitis C: A Critique of the Clinical and Economic Evidence

The National Institute for Health and Care Excellence (NICE) invited the manufacturer of daclatasvir (Bristol-Myers Squibb) to submit clinical and cost-effectiveness evidence for daclatasvir in combination with other medicinal products within its licensed indication for the treatment of chronic hepatitis C, as part of the Institute's single technology appraisal process. The Centre for Reviews and Dissemination and Centre for Health Economics at the University of York were commissioned to act as the independent Evidence Review Group (ERG). This article presents the ERG's critical review of the evidence presented in the company submission in the context of a description of the company submission, and the resulting NICE guidance. The main clinical effectiveness data for daclatasvir in combination with sofosbuvir (daclatasvir + sofosbuvir) were derived from two uncontrolled open-label trials. Among patients with genotype 1 infection, 98-100 % of patients had a sustained virologic response at week 12 (SVR12), overall. Among genotype 3 patients, between 85 and 100 % had SVR12 across patient populations and regimens. The main evidence for daclatasvir + pegylated interferon-α and ribavirin (PR) came from one randomised controlled trial comparing daclatasvir + PR with PR in patients with genotype 4. This found an SVR12 rate of 82 % in previously untreated patients. Serious adverse event rates associated with daclatasvir were low. The lack of comparative trial evidence for daclatasvir + sofosbuvir and many of the comparators defined in the NICE scope meant that established methods for comparing interventions either directly via head-to-head trial comparisons or via adjusted indirect comparisons were not feasible. Comparisons of SVR rates were therefore largely based on unadjusted estimates drawn from individual trial arms and subgroups of individual trial arms. The ERG concluded that, despite limited evidence, daclatasvir in combination with other treatments appeared to be associated with a high SVR rate. Daclatasvir + sofosbuvir was unlikely to be inferior to comparator treatments in genotype 1 patients; but, due to limited evidence, the relative efficacy of daclatasvir and other treatments in genotype 3 and 4 patients or patients with compensated cirrhosis was uncertain. The economic evaluation compared daclatasvir + sofosbuvir and daclatasvir + PR with a wide range of NICE-approved treatments for hepatitis C. The company submission focused on a series of subgroups defined by disease severity (METAVIR fibrosis stage F3, compensated cirrhosis), genotype and treatment history. In the cost-effectiveness analysis, daclatasvir-containing regimens were cost effective at a £20,000-£30,000 per QALY threshold in the following F3 populations: genotype 1 treatment naïve (Incremental cost-effectiveness ratio [ICER] = £19,739/QALY) and treatment experienced (£15,687/QALY) and genotypes 1, 3 and 4 interferon ineligible or intolerant (£5906-£9607/QALY depending on subgroup). In patients with cirrhosis, daclatasvir-containing regimens were not cost effective. The ERG found the company's economic analyses to be highly uncertain and in places biased. However, the ERG found that daclatasvir-containing regimens were cost effective in certain populations with significant fibrosis, and following new analyses by the company after a price reduction, in certain populations with cirrhosis, including patients who were not eligible for or who were intolerant to interferon therapy. The NICE Appraisal Committee's preliminary recommendation was that daclatasvir + sofosbuvir should be available as an option in genotype 1 and 4 patients with significant fibrosis but without cirrhosis, who had either been treated previously or were ineligible or intolerant to interferon. In response to the preliminary recommendation, the manufacturer submitted additional information including comparator SVR rates and a revised confidential price. Following this, the Committee expanded its original recommendation in its Final Appraisal Determination. The recommendation was expanded to include daclatasvir + sofosbuvir as an option for patients with significant fibrosis but without cirrhosis (in previously untreated patients with genotype 1, and genotype 3 patients ineligible or intolerant to interferon) and genotype 1, 3 and 4 cirrhotic patients who were ineligible or intolerant to interferon. Daclatasvir + PR was also recommended as an option for genotype 4 patients who had significant fibrosis or compensated cirrhosis.

Simple Predictive Model for Identifying Patients with Chronic Hepatitis C and Hepatitis C Virus Genotype 4 Infection with a High Probability of Sustained Virologic Response with Peginterferon Alfa-2a/Ribavirin: Pooled Analysis of Data from Two Large, International Cohort Studies

INTRODUCTION

Wherever access to direct-acting antiviral agents is restricted, dual peginterferon/ribavirin (PegIFN/RBV) therapy remains an option for treatment of hepatitis C virus (HCV) genotype 4 (GT4) infection, which predominates in the Middle East and Sub-Saharan Africa. Our goal was to develop a baseline scoring system to identify GT4-infected patients with a low or high probability of achieving a sustained virologic response (SVR) with PegIFN alfa-2a/RBV using data from two large cohort studies.

METHODS

Associations between baseline characteristics and SVR were explored by generalized additive models and multiple logistic regression analysis to develop a predictive model, which was then checked by bootstrapping. The score comprised four factors with points assigned thus: age ≤40, 3 points; >40 but ≤55, 2 points; alanine aminotransferase ≤1 or >3× the upper limit of normal, 1 point; no cirrhosis, 1 point; HCV RNA <50,000 IU/mL, 2 points; 50,000 to <400,000 IU/mL, 1 point. The values for a given patient are summed to produce a score from 0 to 7 where higher scores indicate higher chances of SVR.

RESULTS

Among the 459 patients, 28 (6%), 50 (11%), 92 (20%), 121 (26%), 103 (22%), and 65 (14%) patients had scores of 0-1, 2, 3, 4, 5, and 6-7, respectively, with respective SVR rates of 11%, 28%, 50%, 57%, 63%, and 83%. Relapse rates decreased with increasing prediction score (80%, 39%, 15%, 19%, 5%, and 7%, respectively). SVR rates were consistently higher in Caucasian than Black patients and in patients with a rapid virologic response HCV RNA <50 IU/mL at week 4); however, the trend toward higher SVR rates with increasing score remained apparent in each subgroup.

CONCLUSION

In conclusion, a simple scoring system can be used to identify GT4-infected patients with a high probability of achieving an SVR with PegIFN alfa-2a/RBV.

FUNDING

F. Hoffmann-La Roche Ltd.

Ledipasvir plus sofosbuvir for 12 weeks in patients with hepatitis C genotype 4 infection

Genotype 4 hepatitis C virus (HCV) was considered difficult to treat in the era of pegylated interferon-alpha (Peg-IFN-α) and ribavirin regimens. We evaluated the efficacy and safety of therapy with the nonstructural (NS) 5A inhibitor, ledipasvir, combined with the NS5B polymerase inhibitor, sofosbuvir, in patients with HCV genotype 4. In this phase 2, open-label study, 44 patients (22 treatment naïve and 22 treatment experienced) received a fixed-dose combination tablet of 90 mg of ledipasvir and 400 mg of sofosbuvir orally once-daily for 12 weeks. The primary endpoint was the percentage of patients with HCV RNA <15 IU/mL 12 weeks after stopping therapy (SVR12). Among study participants, HCV genotype 4 subtypes were well represented (4a, n = 25; 4d, n = 10; other subtypes, n = 9). Ten patients (23%) had compensated cirrhosis. Of the 22 treatment-experienced patients, 21 (95%) had a non-CC IL-28B genotype. All 44 patients completed the full 12 weeks of dosing. The SVR12 rate was 93% (41 of 44; 95% confidence interval, 81-99). SVR12 rates were similar between treatment-naïve (95%; 21 of 22) and treatment-experienced (91%; 20 of 22) patients. All 3 patients who did not achieve SVR12 had virological relapse within 4 weeks of the end of treatment; all 3 had baseline HCV RNA ≥800,000 IU/mL, a non-CC IL-28B genotype, and pretreatment NS5A resistance-associated variants. None of the patients who relapsed had cirrhosis. The most common adverse events were asthenia, headache, and fatigue. No patients experienced a serious adverse event.

CONCLUSION

The all-oral regimen of ledipasvir and sofosbuvir is an effective and safe treatment for a wide range of HCV 4 subtypes in both treatment-naïve and -experienced patients, including those with compensated cirrhosis. (EudraCT number: 2013-003978-27; Clinicaltrials.gov NCT02081079) (Hepatology 2016;64:1049-1056).

Management of hepatitis C genotype 4 in the directly acting antivirals era

Genotype 4 chronic hepatitis C (G4 HCV) accounts for 13% of worldwide HCV infections; with 10 million people infected with the virus across the world. Up to the end of 2013, the only treatment option for G4 HCV was treatment with pegylated interferon and ribavirin for 24-48 weeks. Since late 2013, treatment of G4 HCV has been transformed by the licensing of many directly acting antiviral agents (DAA). It is an exciting time to be involved in the management of HCV generally and G4 particularly. Interferon-free DAA regimens are now a reality for G4 HCV. This review will highlight these developments and discuss the data behind the use of these drugs. It will also highlight future regimens that are likely to be available over the coming years.

Daclatasvir combined with peginterferon-α and ribavirin for the treatment of chronic hepatitis C: a meta-analysis

Daclatasvir, a HCV NS5A inhibitor, is a new direct-acting antiviral drug for chronic hepatitis C (CHC). This study aimed to evaluate the efficacy and safety of daclatasvir combined with peginterferon-α (pegIFN-α) and ribavirin (RBV) for the treatment of CHC. The databases of PUBMED, EMBASE, COCHRANE, WANFANG, and CNKI were retrieved to identify eligible studies. Pooled risk ratio (RR) and 95 % confidence interval (CI) were calculated using random or fixed models. A total of six RCTs including 1100 adult patients with CHC met the inclusion criteria and the patients were infected with HCV genotype 1-4, with the genotype 1 infection accounting for 73.1 %. Meta-analysis showed daclatasvir-based combination therapy yielded a significantly higher probability of achieving the overall RVR (46.43 vs. 18.97 %) with pooled RR of 3.77 (95 % CI 1.95-7.28, p < 0.0001) and a slightly higher probability of achieving the overall SVR24 (65.08 vs. 47.77 %) with pooled RR of 1.41 (95 % CI 1.18-1.68, p < 0.0001), and did not show increased adverse events compared with the pegIFN-α/RBV regimen (control group). Subgroup analysis showed the rate of RVR and SVR24 in high-dose daclatasvir (60 mg/day) group were slightly higher than the overall results; the rate of RVR in low-dose daclatasvir (10 mg/day) group was also higher than the control group, but its SVR24 rate was similar between the two groups. Daclatasvir combined with pegIFN-α/RBV is effective and safe in treating adult patients with CHC, especially HCV genotype 1 infection, and daclatasvir (60 mg/day) is a better choice as compared with daclatasvir (10 mg/day).

Analytical performance of the VERIS MDx system HCV assay for detecting and quantifying HCV RNA

BACKGROUND

The diagnosis of HCV relies on the detection of viral RNA.

OBJECTIVE

To evaluate the performance of the VERIS/MDx System HCV Assay, a new automated system for quantifying HCV RNA, and to compare with the COBAS^® Ampliprep/COBAS^® Taqman™ (CAPCTM) HCV Test version 2.0.

STUDY DESIGN

The limit of detection was determined by Probit analysis with the 3rd International WHO HCV standard and precision by assaying in duplicate control samples with HCV RNA concentrations of 7.9; 5.0; 3.4; 1.6 and 0logIU/ml over 20 days. Analytical specificity was assessed by assaying 180 samples from negative anti-HCV and HCV RNA blood donors and linearity with replicates of serial dilutions of a clinical plasma (6.4-0.6logIU/ml). We compared the VERIS MDx HCV and CAPCTM HCV assays by testing 209 samples.

RESULTS

The limit of detection was 6.1IU/ml [CI 95%: 5.0-8.3] and the precision, given by the standard deviation, was ≤0.11logIU/ml. Specificity was 100%. The linearity ranged from 1.5 to 6.4logIU/ml. Passing-Bablok regression analysis gave: VERIS logIU/ml=-0.33+[1.04× CAPCTM] logIU/ml, with biases for the 25th, 50th, 75th percentiles of 0.18, -0.10 and -0.06logIU/ml. The two assays were well correlated (ρ=0.92, p<0.001) and Bland-Altman analysis gave biases of 0.12, logIU/ml for genotype 1, -0.19 for genotype 2, -0.26 for genotype 3, and -0.77 for genotype 4.

CONCLUSION

The VERIS MDx HCV assay performed well. But, we observed an under-quantification of the genotype 4 samples.

Characterization of NS5A polymorphisms and their impact on response rates in patients with HCV genotype 2 treated with daclatasvir-based regimens

OBJECTIVE

Daclatasvir (DCV) is a pan-genotypic non-structural protein 5A (NS5A) inhibitor that is approved for treatment of hepatitis C virus (HCV) genotype (GT)1 and GT3 in the USA and GT1, GT3 and GT4 in Europe. We set out to examine the impact of daclatasvir-based regimens on the sustained virologic response (SVR) in patients with GT2 infection with respect to GT2 subtype and NS5A polymorphisms at amino acid positions associated with daclatasvir resistance.

METHODS

Analyses were performed on 283 GT2 NS5A sequences from five daclatasvir regimen-based clinical trials (ClinicalTrials.gov: NCT-01257204, NCT-01359644, NCT-02032875, NCT-02032888 and NCT-01616524) and 143 NS5A sequences from the Los Alamos HCV database. Susceptibility analyses of substitutions at amino acid positions associated with daclatasvir resistance and patient-derived NS5A sequences were performed using an in vitro HCV replication assay.

RESULTS

Of 13 GT2 subtypes identified from 426 NS5A sequences, the most prevalent were GT2a (32%), GT2b (48%) and GT2c (10%). The most prevalent NS5A polymorphism was L31M (GT2a = 88%; GT2b = 59%; GT2c = 10%). Substitutions identified in 96% of GT2 NS5A sequences exhibited daclatasvir EC₅₀ values ranging from 0.005 to 20 nM when tested in vitro. A similar range in daclatasvir EC₅₀ values was observed for 16 diverse GT2 patient-derived NS5A sequences (EC₅₀ = 0.005-60 nM). Depending on the daclatasvir-based regimen studied (daclatasvir/interferon-based or daclatasvir/sofosbuvir-based), SVR rates ranged from 90% to 100% in GT2 patients with the most prevalent baseline NS5A-L31M polymorphism, compared with from 96% to 100% without this polymorphism.

CONCLUSIONS

High SVR rates were achieved in patients infected with GT2 treated with daclatasvir-based regimens irrespective of GT2 subtype or baseline NS5A polymorphisms.

Daclatasvir-based Treatment Regimens for Hepatitis C Virus Infection: A Systematic Review and Meta-Analysis

CONTEXT

Direct acting antivirals (DAAs) have recently emerged as a promising therapeutic regimen for the treatment of hepatitis C virus (HCV) infection, which is a major public health problem. Among the known DAAs, daclatasvir (DCV), an inhibitor of the non-structural 5A protein, has been used in combination with several drugs for treatment of infection with HCV of different genotypes under different conditions. We conducted a systematic review and meta-analysis of combination therapy with DCV.

EVIDENCE ACQUISITION

We performed a systematic search in PubMed, Scopus, Science Direct and Web of Science with appropriate keywords for DCV. Studies that evaluated any regimen containing DCV and reported the sustained virological response (SVR) 12 weeks after therapy based on the HCV genotype, treatment duration and use of ribavirin (RBV) were included. The selected studies were considered for meta-analysis using STATA 11.0.

RESULTS

We found six different regimens containing DCV: DCV/asunaprevir (ASV), DCV/ASV/beclubavir, DCV/pegylated interferon lambda or alpha/RBV with or without ASV, DCV/simeprevir, DCV/VX-135 and DCV/sofosbuvir (SOF). Most of these regimens were used for the treatment of HCV genotype 1 infections, and in most cases, treatment failure was noted in subtype 1a infections. Among all these regimens, DCV/SOF with or without RBV for 12 or 24 weeks was found to be an efficacious approach for treatment of different types of patients with infections with different HCV genotypes.

CONCLUSIONS

Among the treatment regimens containing DCV, DCV/SOF has the highest SVR rate for the treatment of infection with different HCV genotypes in different patient contexts; thus, this regimen shows promise for the treatment of HCV infections.

Daclatasvir/peginterferon lambda-1a/ribavirin in patients with chronic HCV infection and haemophilia who are treatment naïve or prior relapsers to peginterferon alfa-2a/ribavirin

AIM

This study explores the potential role of a novel interferon-containing regimen for treatment of patients with chronic hepatitis C (CHC) and underlying haemophilia.

METHODS

This trial (NCT01741545) was an open-label, non-randomized phase 3 study, which included adult haemophiliacs with hepatitis C virus (HCV). Patients with HCV genotypes (GT)-2 or -3 were treated with Lambda-IFN/ribavirin (RBV)/daclatasvir (DCV) for 12 weeks (cohort A). Patients with HCV GT-1b or -4 were treated with Lambda-IFN/RBV/DCV for 12 weeks, followed by Lambda-IFN/RBV for an additional 12 weeks (cohort B). The primary endpoint was the proportion of patients with a sustained virologic response at post-treatment follow-up week 12 (SVR12). Clinical development of Lambda-IFN was discontinued during this trial leading to study termination before a 24-week post-treatment follow-up was obtained for all participants.

RESULTS

Overall, 51 patients were treated (cohort A, n = 12; cohort B, n = 39). The proportion of patients achieving SVR12 was 92% in cohort A and 90% in cohort B. Therapy was generally well tolerated. The most common adverse events (AEs) were related to elevations in serum transaminases and/or bilirubin. Five serious AEs, four discontinuations due to AEs, and no deaths were reported. The rate of grade 3-4 bilirubin elevations was 17-18% across cohorts.

CONCLUSION

Lambda-IFN/RBV/DCV treatment demonstrated a high SVR rate and was generally well tolerated with a safety profile consistent with expectations for this special patient population. This study supports use of DCV as part of a combination treatment regimen for haemophiliacs with CHC.

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".

Protease Inhibitors Drug Resistance Mutations in Turkish Patients with Chronic Hepatitis C

BACKGROUND

Drug resistance development is an expected problem during treatment with protease inhibitors (PIs), this is largely due to the fact that Pls are low-genetic barrier drugs. Resistance-associated variants (RAVs) however may also occur naturally, and prior to treatment with Pls, the clinical impact of this basal resistance remains unknown. In Turkey, there is yet to be an investigation into the hepatitis C (HCV) drug associated resistance to oral antivirals.

MATERIALS AND METHODS

178 antiviral-naïve patients infected with HCV genotype 1 were selected from 27 clinical centers of various geographical regions in Turkey and included in the current study. The basal NS3 Pls resistance mutations of these patients were analyzed.

RESULTS

In 33 (18.5%) of the patients included in the study, at least one mutation pattern that can cause drug resistance was identified. The most frequently detected mutation pattern was T54S while R109K was the second most frequently detected. Following a more general examination of the patients studied, telaprevir (TVR) resistance in 27 patients (15.2%), boceprevir (BOC) resistance in 26 (14.6%) patients, simeprevir (SMV) resistance in 11 (6.2%) patients and faldaprevir resistance in 13 (7.3%) patients were detected. Our investigation also revealed that rebound developed in the presence of a Q80K mutation and amongst two V55A mutations following treatment with TVR, while no response to treatment was detected in a patient with a R55K mutation.

CONCLUSION

We are of the opinion that drug resistance analyses can be beneficial and necessary in revealing which variants are responsible for pre-treatment natural resistance and which mutations are responsible for the viral breakthrough that may develop during the treatment.

Systematic review: current concepts and challenges for the direct-acting antiviral era in hepatitis C cirrhosis

BACKGROUND

The burden of HCV cirrhosis is high and projected to increase significantly over the next decade. While interferon therapy is problematic in HCV cirrhosis, the era of direct-acting anti-viral (DAA) therapy provides effective treatment for patients with cirrhosis.

AIM

To systematically review the results of DAA therapy to date in patients with HCV cirrhosis, and highlight the ongoing challenges for DAA therapy in this population.

METHODS

A structured Medline search was conducted to obtain phase II and III HCV trials in patients with cirrhosis. Citations from review articles were cross-referenced and conference abstracts from EASL and AASLD liver meetings for the preceding 3 years were reviewed manually. Keywords used included hepatitis C, cirrhosis and the DAA's: sofosbuvir, ledipasvir, velpatasvir, grazoprevir, elbasvir, daclatasvir, beclabuvir, asunaprevir, simeprevir, paritaprevir, ombitasvir and dasabuvir.

RESULTS

Successful direct-acting anti-viral treatment is now possible in patients with HCV-related cirrhosis including those with liver decompensation with several regimens now offering sustained virological response (SVR) of 90-95%. Overall success rates in GT1 cirrhosis are excellent while GT3-infected patients with cirrhosis remain hard to cure. The pangenotypic combination of sofosbuvir and velpatasvir holds promise for GT3 cirrhosis achieving SVR of ~90%.

CONCLUSIONS

Potent DAA therapies provide much needed, safe and highly effective treatment options for persons with HCV cirrhosis including those previously deemed unsuitable for treatment. Combination therapy with two or more classes of drug is essential to achieve high efficacy and minimise viral resistance, with the role of ribavirin still under evaluation. However, several challenges remain including the hard-to-cure groups of GT3 cirrhosis and direct-acting anti-viral failures, and managing drug-drug interactions.

Indian National Association for Study of the Liver (INASL) Guidance for Antiviral Therapy Against HCV Infection: Update 2016

India contributes significantly to the global burden of HCV. While the nucleoside NS5B inhibitor sofosbuvir became available in the Indian market in March 2015, the other directly acting agents (DAAs), Ledipasvir and Daclatasvir, have only recently become available in the India. The introduction of these DAA in India at a relatively affordable price has led to great optimism about prospects of cure for these patients as not only will they provide higher efficacy, but combination DAAs as all-oral regimen will result in lower side effects than were seen with pegylated interferon alfa and ribavirin therapy. Availability of these newer DAAs has necessitated revision of INASL guidelines for the treatment of HCV published in 2015. Current considerations for the treatment of HCV in India include the poorer response of genotype 3, nonavailability of many of the DAAs recommended by other guidelines and the cost of therapy. The availability of combination DAA therapy has simplified therapy of HCV with decreased reliance of evaluation for monitoring viral kinetics or drug related side effects.

Direct-acting Antiviral Agents Resistance-associated Polymorphisms in Chinese Treatment-naïve Patients Infected with Genotype 1b Hepatitis C Virus

Background:

It has been reported that several baseline polymorphisms of direct-acting antivirals (DAAs) agents resistance-associated variants (RAVs) would affect the treatment outcomes of patients chronically infected with hepatitis C virus (CHC). The aim of this study is to investigate the prevalence of DAAs RAVs in treatment-naïve GT1b CHC patients.

Methods:

Direct sequencing and ultra-deep sequencing of the HCV NS3, NS5A, and NS5B gene were performed in baseline serum samples of treatment-naïve patients infected with genotype 1b hepatitis C virus (HCVs).

Results:

One hundred and sixty CHC patients were studied. Complete sequence information was obtained for 145 patients (NS3), 148 patients (NS5A), and 137 patients (NS5B). Treatment-failure associated variants of DAAs were detected: 56.6% (82/145) of the patients presented S122G for simeprevir (NS3 protease inhibitor); 10.1% (14/148) of the patients presented Y93H for daclatasvir and ledipasvir (NS5A protein inhibitors); 94.2% (129/137) of the patients presented C316N for sofosbuvir (NS5B polymerase inhibitor). Nearly, all of the DAAs RAVs detected by ultra-deep sequencing could be detected by direct sequencing.

Conclusions:

The majority of genotype 1b CHC patients in China present a virus population carrying HCV DAAs RAVs. Pretreatment sequencing of HCV genome might need to be performed when patients infected with GT1b HCV receiving DAAs-containing regimens in China. Population sequencing would be quite quantified for the work.

Daclatasvir combined with sofosbuvir or simeprevir in liver transplant recipients with severe recurrent hepatitis C infection

Daclatasvir (DCV) is a potent, pangenotypic nonstructural protein 5A inhibitor with demonstrated antiviral efficacy when combined with sofosbuvir (SOF) or simeprevir (SMV) with or without ribavirin (RBV) in patients with chronic hepatitis C virus (HCV) infection. Herein, we report efficacy and safety data for DCV-based all-oral antiviral therapy in liver transplantation (LT) recipients with severe recurrent HCV. DCV at 60 mg/day was administered for up to 24 weeks as part of a compassionate use protocol. The study included 97 LT recipients with a mean age of 59.3 ± 8.2 years; 93% had genotype 1 HCV and 31% had biopsy-proven cirrhosis between the time of LT and the initiation of DCV. The mean Model for End-Stage Liver Disease (MELD) score was 13.0 ± 6.0, and the proportion with Child-Turcotte-Pugh (CTP) A/B/C was 51%/31%/12%, respectively. Mean HCV RNA at DCV initiation was 14.3 × 6 log10 IU/mL, and 37% had severe cholestatic HCV infection. Antiviral regimens were selected by the local investigator and included DCV+SOF (n = 77), DCV+SMV (n = 18), and DCV+SMV+SOF (n = 2); 35% overall received RBV. At the end of treatment (EOT) and 12 weeks after EOT, 88 (91%) and 84 (87%) patients, respectively, were HCV RNA negative or had levels <43 IU/mL. CTP and MELD scores significantly improved between DCV-based treatment initiation and last contact. Three virological breakthroughs and 2 relapses occurred in patients treated with DCV+SMV with or without RBV. None of the 8 patient deaths (6 during and 2 after therapy) were attributed to therapy. In conclusion, DCV-based all-oral antiviral therapy was well tolerated and resulted in a high sustained virological response in LT recipients with severe recurrent HCV infection. Most treated patients experienced stabilization or improvement in their clinical status.

Daclatasvir vs telaprevir plus peginterferon alfa/ribavirin for hepatitis C virus genotype 1

AIM

To evaluate daclatasvir vs telaprevir, each combined with peginterferon alfa-2a/ribavirin (pegIFN/RBV), in treatment-naive hepatitis C virus (HCV) genotype (GT) 1-infected patients.

METHODS

In this phase 3, randomized, open-label, noninferiority study, 602 patients were randomly assigned (2:1) to daclatasvir vs telaprevir, stratified by IL28B rs12979860 host genotype (CC vs non-CC), cirrhosis status (compensated cirrhosis vs no cirrhosis), and HCV GT1 subtype (GT1a vs GT1b). Patients were selected by study inclusion criteria from a total of 793 enrolled patients. Patients received daclatasvir 60 mg once daily or telaprevir 750 mg 3 times daily plus pegIFN/RBV. Daclatasvir recipients received 24 wk of daclatasvir plus pegIFN/RBV; those without an extended rapid virologic response (eRVR; undetectable HCV-RNA at weeks 4 and 12) received an additional 24 wk of pegIFN/RBV. Telaprevir-treated patients received 12 wk of telaprevir plus pegIFN/RBV followed by 12 (with eRVR) or 36 (no eRVR) wk of pegIFN/RBV. The primary objective was to compare for noninferiority of sustained virologic response rates at posttreatment week 12 (SVR12) in GT1b-infected patients. Key secondary objectives were to demonstrate that the rates of anemia (hemoglobin < 10 g/dL) and rash-related events, through week 12, were lower with daclatasvir + pegIFN/RBV than with telaprevir + pegIFN/RBV among GT1b-infected patients. Resistance testing was performed using population-based sequencing of the NS5A region for all patients at baseline, and for patients with virologic failure or relapse and HCV-RNA ≥ 1000 IU/mL, to investigate any link between NS5A polymorphisms associated with daclatasvir resistance and virologic outcome.

RESULTS

Patient demographics and disease characteristics were generally balanced across treatment arms; however, there was a higher proportion of black/African Americans in the daclatasvir groups (6.0% and 8.2% in the GT1b and GT1a groups, respectively) than in the telaprevir groups (2.2% and 3.0%). Among GT1b-infected patients, daclatasvir plus pegIFN/RBV was noninferior to telaprevir plus pegIFN/RBV for SVR12 [85% (228/268) vs 81% (109/134); difference, 4.3% (95%CI: -3.3% to 11.9%)]. Anemia (hemoglobin < 10 g/dL) was significantly less frequent with daclatasvir than with telaprevir [difference, -29.1% (95%CI: -38.8% to -19.4%)]. Rash-related events were also less common with daclatasvir than with telaprevir, but the difference was not statistically significant. In GT1a-infected patients, SVR12 was 64.9% with daclatasvir and 69.7% with telaprevir. Among both daclatasvir and telaprevir treatment groups, across GT1b- or GT1a-infected patients, lower response rates were observed in patients with IL28B non-CC and cirrhosis - factors known to affect response to pegIFN/RBV. Consistent with these observations, a multivariate logistic regression analysis in GT1b-infected patients demonstrated that SVR12 was associated with IL28B host genotype (CC vs non-CC, P = 0.011) and cirrhosis status (absent vs present, P = 0.031). NS5A polymorphisms associated with daclatasvir resistance (at L28, R30, L31, or Y93) were observed in 17.3% of GT1b-infected patients at baseline; such variants did not appear to be absolute predictors of failure since 72.1% of these patients achieved SVR12 compared with 86.9% without these polymorphisms. Among GT1b-infected patients, treatment was completed by 85.4% (229/268) in the daclatasvir group, and by 85.1% (114/134) in the telaprevir group, and among GT1a-infected patients, by 67.2% (90/134) and 69.7% (46/66), respectively. Discontinuations (of all 3 agents) due to an AE were more frequent with telaprevir than with daclatasvir, whereas discontinuations due to lack of efficacy were more frequent with daclatasvir, due, in part, to differences in futility criteria.

CONCLUSION

Daclatasvir plus pegIFN/RBV demonstrated noninferiority to telaprevir plus pegIFN/RBV for SVR12 and was well-tolerated in treatment-naive GT1b-infected patients, supporting the use of daclatasvir with other direct-acting antivirals.