ABT-450/r-ombitasvir and dasabuvir with ribavirin for hepatitis C with cirrhosis

Real-world efficacy and safety of ombitasvir, paritaprevir/r+dasabuvir+ribavirin in genotype 1b patients with hepatitis C virus cirrhosis

BACKGROUND

Direct antiviral agents (DAA) showed very good results in terms of efficacy and safety in clinical trials, but real-life data are still needed in order to confirm this profile.

MATERIAL AND METHODS

In Romania, through a nationwide government-funded programme in 2015-2016, approx.5800 patients with virus C cirrhosis received fully reimbursed DAA therapy with OBV/PTV/r+DSV+RBV for 12 weeks. We analysed a national prospective cohort enrolling the first 2070 patients, all with genotype 1b. The only key inclusion criteria was advanced fibrosis (Metavir stage F4) confirmed by Fibromax testing (or liver biopsy/Fibroscan). Efficacy was assessed by the percentage of patients achieving SVR 12 weeks post-treatment (SVR12).

RESULTS

Forty patients stopped the treatment because of hepatic decompensation (1.9%), 21 stopped because of other adverse events and one was lost to follow-up. This cohort was 51% females, mean age 60 years (25÷82), 67% pretreated, 70% associated NASH, 67% with severe necro-inflammation (severity score 3-Fibromax), 37% with comorbidities, 10.4% with Child Pugh A6, 0.5% B7. The median MELD score was 8.09 (6 ÷ 22). SVR by intention-to-treat was reported in 1999/2070(96.6%), 55/2070 failed to respond. Liver decompensation was statistically associated in multivariate analysis with platelets< 105 /mm3 (P = .03), increased total bilirubin (P < .001), prolonged INR (P = .02), and albumin<3.5 g/dL (P = .03).

CONCLUSIONS

OBV/PTV/r+DSV+RBV proved to be highly efficient in our population of cirrhotics with a 96.6% SVR. Serious adverse events related to therapy were reported in 61/2070(2.9%), most of them liver decompensation (1.9%), related to hepatic dysfunction, and lower platelet count.

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).

Host-targeting therapies for hepatitis C virus infection: current developments and future applications

Chronic hepatitis C virus (HCV) infection is a leading cause of chronic liver diseases and hepatocellular carcinoma (HCC) worldwide. In the past few years, anti-HCV therapies have undergone a revolution with the approval of multiple direct-acting antivirals (DAAs), which enable interferon-free treatments with considerable improvement of sustained virologic response in patients. Today, DAAs have become the standard of care for HCV therapy. However, several limitations remain, which include access to therapy, treatment failure in a subset of patients and persistent risk of HCC development following cure in patients with advanced fibrosis. By targeting conserved host proteins involved in the HCV life cycle, host-targeting agents (HTAs) offer opportunities for pan-genotypic antiviral approaches with a high barrier to drug resistance. Moreover, when applied in combination with DAAs, HTAs could improve the management of difficult-to-treat patients by acting through a complementary mechanism of action. In this review, we summarize the different HTAs evaluated in preclinical and clinical development and discuss their potential role for anti-HCV therapies.

Stagnation of histopathological improvement is a predictor of hepatocellular carcinoma development after hepatitis C virus eradication

BACKGROUND

Hepatocellular carcinoma (HCC) develops in some patients who achieve sustained virological response (SVR) against hepatitis C virus (HCV) infection via anti-HCV therapy. To examine the pathogenesis of HCC development after HCV eradication, histopathological changes and clinical markers were evaluated in SVR patients.

METHODS

Of 654 SVR patients treated with interferon (IFN)-based therapies, 34 patients who had undergone liver biopsy before initiating IFN therapy and after SVR achievement were enrolled: 11 patients with HCC and 23 patients without HCC (male/female, 9/2 and 8/15, respectively: age, 58 ± 5 and 54 ± 11 years, respectively). We compared the clinical and histopathological factors between the two groups. Immunohistochemistry for Cytoglobin (CYGB) and α smooth muscle actin (α-SMA) was also performed.

RESULTS

At baseline, prior to initiating the IFN-based therapy, there were significant differences between the SVR-non-HCC and SVR-HCC groups in the male gender, HBc antibody positivity, prothrombin activity, and histological inflammatory grade. Histopathological evaluation, using the new Inuyama classification system, revealed an improvement in the inflammatory grade, from 2.1 ± 0.6 to 1.0 ± 0.6 (p < 0.0001), whereas the fibrosis stage remained unchanged, from 2.3 ± 0.9 to 2.0 ± 1.2 (p = 0.2749), during the 97 ± 72-month observation period in the SVR-HCC group. Both the grade and stage scores were significantly improved in the SVR-non-HCC group. The area of collagen deposition, evaluated using Sirius red staining, showed a marked decrease, from 18.6 ± 7.6% to 7.7 ± 4.6%, in the SVR-non-HCC group, with no change in the SVR-HCC group. CYGB- and α-SMA-positive hepatic stellate cells (HSCs), indicative of the HSC activated phenotype, remained in the fibrotic tissue of livers among patients in the SVR-HCC group.

CONCLUSION

Stagnation of fibrosis regression is associated with a high risk for HCC after SVR. HSC activation may inhibit improvement in fibrosis after SVR and potentially contribute to hepatocarcinogenesis.

Treatment of hepatitis C virus infection for adults and children: updated Swedish consensus guidelines 2017

AIM

Following the approval of two new therapeutic combinations within the European Union in 2017, the former Swedish recommendations for the treatment of hepatitis C virus (HCV) infection from 2016 were deemed in need of updating.

MATERIALS AND METHODS

An expert meeting to this end was held in Stockholm, Sweden in October 2017.

RESULTS AND CONCLUSIONS

An interferon-free combination of direct-acting antiviral agents is now recommended for all patients with chronic HCV infection, regardless of liver fibrosis stage, in order to limit morbidity and spread of the disease. An extended discussion of treatment for people who inject drugs in order to diminish transmission is included.

Impact of sustained virologic response on short-term clinical outcomes in hepatitis C-related cirrhosis

BACKGROUND

Hepatitis C virus (HCV) is a common cause of cirrhosis, leading to increased morbidity and mortality. Treatment of the underlying etiology has been shown to improve fibrosis and cirrhosis.

AIM

We sought to evaluate the impact of a sustained virologic response on liver chemistries, model for end stage liver disease (MELD) score, Child-Pugh-Turcotte score (CPT), and fibrosis 4 score (FIB4) in patients with liver cirrhosis secondary to HCV with portal hypertension, with or without decompensation.

METHODS

Patients with HCV seen in our transplant clinic between June 2013 and September 2015 were identified using ICD-9 code 573.3. Charts were reviewed retrospectively.

RESULTS

We collected data from 92 patients with a mean pretreatment MELD score of 9.16±2.98. The most common genotype was Ia, n=79 (86%). The mean duration of follow-up was 7.52±2.25 months. Transaminitis improved significantly at follow-up versus pretreatment [mean aspartate transaminase from 81.2±62.9 to 32.4±12.0 (P<0.0001); alanine transaminase 74.7±77.8 to 27.7±19.4 (P<0.0001)]. Albumin, bilirubin, and α-fetoprotein improved significantly. MELD scores improved in patients with pretreatment scores greater than 10 (P<0.0003), but not in patients with pretreatment scores less than 10 (P=0.501). The CPT score decreased from 6.1±0.9 to 5.8±0.9 (P<0.0024). The FIB4 score improved significantly in patients with baseline FIB4 more than 3.24, but not with higher baseline FIB4.

CONCLUSION

Use of direct antivirals in patients with decompensated cirrhosis because of HCV leads to improved MELD, FIB4, and CPT scores.

Real-world effectiveness and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir with or without ribavirin for patients with chronic hepatitis C virus genotype 1b infection in Taiwan

BACKGROUND AND AIM

The real-world effectiveness and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir (PrOD) remain limited for East Asian hepatitis C virus genotype 1b (HCV-1b) patients. The study aimed to evaluate the antiviral responses of PrOD-based regimens for HCV-1b patients in Taiwan.

METHODS

The study performed a retrospective analysis of 103 HCV-1b patients receiving PrOD with or without ribavirin (RBV) for 12 weeks. Data were analyzed to assess the on-treatment and off-therapy HCV viral load and on-treatment adverse events. The pre-specified characteristics related to sustained virologic response 12 weeks off therapy (SVR12 ) were compared.

RESULTS

At treatment week 4, 100 of 102 patients (98.0%) had serum HCV RNA level < 25 IU/mL. The SVR12 was achieved in 101 of 103 patients (98.1%, [95% confidence interval: 93.2-99.5%]). All except one (99.0%) patients tolerated treatment well without treatment interruption. One cirrhotic patient discontinued treatment at week 1 due to hepatic decompensation. Twenty-four patients (23.3%) had ≥ grade 2 elevation in total bilirubin levels, and 21 of them (87.5%) had indirect type hyperbilirubinemia. The stratified SVR12 rates were comparable in terms of sex, age, body mass index, prior treatment experience, hepatitis B virus surface antigen status, RBV usage, baseline and week 2 viral load, renal function, and hepatic fibrosis stage.

CONCLUSIONS

Paritaprevir/ritonavir, ombitasvir, and dasabuvir with or without RBV are efficacious and generally well tolerated for treatment of HCV-1b patients in Taiwan.

Predictors of functional benefit of hepatitis C therapy in a ‘real-life’ cohort

AIM

To define predictors of functional benefit of direct-acting antivirals (DAAs) in patients with chronic hepatitis C virus (HCV) infection and liver cirrhosis.

METHODS

We analysed a cohort of 199 patients with chronic HCV genotype 1, 2, 3 and 4 infection involving previously treated and untreated patients with compensated (76%) and decompensated (24%) liver cirrhosis at two tertiary centres in Germany. Patients were included with treatment initiation between February 2014 and August 2016. All patients received a combination regimen of one or more DAAs for either 12 or 24 wk. Predictors of functional benefit were assessed in a univariable as well as multivariable model by binary logistic regression analysis.

RESULTS

Viral clearance was achieved in 88% (175/199) of patients. Sustained virological response (SVR) 12 rates were as follows: among 156 patients with genotype 1 infection the SVR 12 rate was 90% (n = 141); among 7 patients with genotype 2 infection the SVR 12 rate was 57% (n = 4); among 30 patients with genotype 3 infection the SVR 12 rate was 87% (n = 26); and among 6 patients with genotype 4 infection the SVR 12 rate was 67% (n = 4). Follow-up MELD scores were available for 179 patients. A MELD score improvement was observed in 37% (65/179) of patients, no change of MELD score in 41% (74/179) of patients, and an aggravation was observed in 22% (40/179) of patients. We analysed predictors of functional benefit from antiviral therapy in our patients beyond viral eradication. We identified the Child-Pugh score, the MELD score, the number of platelets and the levels of albumin and bilirubin as significant factors for functional benefit.

CONCLUSION

Our data may contribute to the discussion of potential risks and benefits of antiviral therapy with individual patients infected with HCV and with advanced liver disease.

Hepatitis C virus drug resistance associated substitutions and their clinical relevance: Update 2018

Nowadays, due to the development of potent Direct-Acting Antiviral Agents (DAAs) that specifically target NS3, NS5A and NS5B viral proteins, several new and highly efficacious options to treat chronic Hepatitis C virus (HCV) infection are available. The natural presence of resistance associated substitutions (RASs), as well as their rapid emergence during incomplete drug-pressure, are intrinsic characteristics of HCV that greatly affect treatment outcome and the chances to achieve a virolgical cure. To date, a high number of RASs in NS3, NS5A, and NS5B have been associated in vivo and/or in vitro with reduced susceptibility to DAAs, but no comprehensive RASs list is available. This review thus provides an updated, systematic overview of the role of RASs to currently approved DAAs or in phase II/III of clinical development against HCV-infection, discriminating their impact in different HCV-genotypes and DAAs, providing assistance for a fruitful use of HCV resistance testing in clinical practice.

Trend of estimated glomerular filtration rate during ombistasvir/paritaprevir/ritonavir plus dasabuvir ± ribavirin in HIV/HCV co-infected patients

The renal function is a key-issue in HIV/HCV co-infected patients, nevertheless, it has not established so far whether HCV treatment with new direct acting agents could impact on estimated glomerular filtration rate (eGFR) variations. In the present work, we examined the real-life data on renal function that have been prospectively collected in the SIMIT compassionate-use program of ombitasvir/paritaprevir/ritonavir plus dasabuvir (OBV/PTV/r + DSV) in 144 HIV/HCV genotype 1 co-infected patients. The population was 74% male, 30.5% in CDC stage C, with median age of 52 years (48.0-56.5) and median liver stiffness of 7.8 kPa (6.7-9.2). Median baseline eGFR was 102.0 (90.8-108.1), changing to 99.8 (83.5-104.8) at the end of treatment (EoT), and 100.0 (87.3-105.6) 12 weeks after the EoT (FU12), p<0.0001. No patient had grade 3-4 increase of creatinine. At EoT 60/144 (41.7%) patients had ≥ 5% reduction in their eGFR, confirmed at FU12 in 39/60 (65.0%) cases. Longer duration of HCV infection (cut-off 12.9 years), lower HCV-RNA viral load (cut-off 1,970,160 IU/ml) and lower platelet count (cut-off 167,000 x106/L) were significantly associated with eGFR decline at logistic analysis (adjOR 2.9, 95%CI 1.0-8.8, p = 0.05; adjOR 3.5, 95%CI 1.2-10.4, p = 0.02; adjOR 2.8, 95%CI 1.1-6.8, p = 0.03, respectively). After repeating the analysis throughout a mixed model, a higher eGFR decline was highlighted in patients concomitantly treated with tenofovir (p = 0.0001), ribavirin (p = 0.0001), or integrase inhibitors (p <0.0001), with longer duration of HIV (p = 0.0002) and HCV infection (p = 0.035), lower baseline HCV RNA (p <0.0001), previous HCV treatment (p<0.0001), and older age (p<0.0001). In conclusion, our study confirms a good renal safety profile of OBV/PTV/r + DSV treatment in HIV/HCV patients, and the median decline of 2 ml/min in eGFR, albeit statistically significant, is of doubtful clinical significance. The role of aging, concomitant therapies and duration of HIV/HCV infection needs to be further investigated.

Design, synthesis and identification of silicon-containing HCV NS5A inhibitors with pan-genotype activity

Modification of a HCV NS5A inhibitor, ombitasvir, led to the identification of 10d with improved pan-genotype NS5A inhibition and better pharmacokinetic properties. The key structural changes to ombitasvir include bioisosteric replacement of carbon with silicon atom. Compared with ombitasvir, the activity of anti-HCV genotypes (GT 1 to 6) of 10d is increased to some extent, especially the inhibitory activity against genotype 3a and 6a is increased by more than seven times, and the dog's in vivo pharmacokinetics properties were also superior to ombitasvir. Further drug evaluation showed that 10d was similar to ombitasvir on plasma protein binding and liver distribution profiles, with no cytotoxicity and no inhibitory effect on both CYP 450 and hERG ligand binding. However, permeability assay results indicated that 10d was not the substrate of P-gp or BCRP transporter, which is different from that of ombitasvir. The results of a 14-day repeat-dose toxicity study identified no toxicity with 10d. Our findings in preclinical tests suggest that the silicon-containing compound 10d could be worthy of continued study as a potential drug candidate.

Comparison of cobas HCV GT against Versant HCV Genotype 2.0 (LiPA) with confirmation by Sanger sequencing

BACKGROUND

Correct identification of infecting hepatitis C virus (HCV) genotype is helpful for targeted antiviral therapy.

OBJECTIVES

Here, we compared the HCV genotyping performance of the cobas HCV GT assay against the Versant HCV Genotype 2.0 (LiPA) assay, using 97 archived serum samples.

STUDY DESIGN

In the event of discrepant or indeterminate results produced by either assay, the core and NS5B regions were sequenced.

RESULTS

Of the 97 samples tested by the cobas, 25 (26%) were deemed indeterminate. Sequencing analyses confirmed 21 (84%) of the 25 samples as genotype 6 viruses with either subtype 6m, 6n, 6v, 6xa, or unknown subtype. Of the 97 samples tested by the LiPA, thirteen (13%) were deemed indeterminate. Seven (7%) were assigned with genotype 1, with unavailable/inconclusive results from the core region of the LiPA. Notably, the 7 samples were later found to be either genotype 3 or 6 by sequencing analyses. Moreover, 1 sample by the LiPA was assigned as genotypes 4 (cobas: indeterminate) but were later found to be genotype 3 by sequencing analyses, highlighting its limitation in assigning the correct genotype.

CONCLUSIONS

The cobas showed similar or slightly higher accuracy (100%; 95% CI 94-100%) compared to the LiPA (99%; 95% CI 92-100%). Twenty-six percent of the 97 samples tested by the cobas had indeterminate results, mainly due to its limitation in identifying genotype 6 other than subtypes 6a and 6b. This presents a significant assay limitation in Southeast Asia, where genotype 6 infection is highly prevalent.

Exposure-Safety Response Relationship for Ombitasvir, Paritaprevir/Ritonavir, Dasabuvir, and Ribavirin in Patients with Chronic Hepatitis C Virus Genotype 1 Infection: Analysis of Data from Five Phase II and Six Phase III Studies

BACKGROUND AND OBJECTIVES

All-oral direct-acting antiviral regimens that include combinations of ombitasvir, paritaprevir, ritonavir, and dasabuvir with or without ribavirin were evaluated in hepatitis C virus-infected patients in phase II/III clinical studies. The objective of these analyses was to quantify the relationship between exposures of the components of the regimen and laboratory values and to determine covariates that could influence the relationship.

METHODS

Exposure-safety response relationships between individual components of the direct-acting antiviral regimens and clinically important laboratory values were explored using data from 2998 patients from 11 phase II/III clinical studies. Multivariate logistic regression analyses were used to identify significant relationships between predictor variables and response variables.

RESULTS

No statistically significant associations were observed between ombitasvir, dasabuvir, or ritonavir exposures and maximum post-baseline alanine aminotransferase (ALT) or total bilirubin grade or minimum hemoglobin grade. A two-fold increase in paritaprevir exposure from therapeutic exposure was predicted to increase the probability of experiencing a grade 3 or higher increase in ALT by 0.5% and bilirubin by 1.1%. In the phase II/III clinical studies, ALT and bilirubin increases were reversible with continued dosing or after treatment cessation. Other correlates with adverse events of clinical importance included concomitant ribavirin treatment, sex, race, and presence of cirrhosis, consistent with previous observations.

CONCLUSIONS

Exposure-response analyses from phase II/III studies with the combination direct-acting antiviral regimen indicated no statistically significant relationships with ombitasvir, dasabuvir, or ritonavir exposure, but a statistically significant association was observed between paritaprevir exposure and the probability of experiencing a grade 3 or higher increase in ALT or bilirubin.

Efficacy of Interferon-Free Therapies for Chronic Hepatitis C: A Systematic Review of All Randomized Clinical Trials

BACKGROUND AND OBJECTIVES

Second-generation direct-acting antivirals (DAAs) have recently arisen as more effective and safer treatments for chronic hepatitis C. These drugs can be combined into treatments without interferon (IFN), and are therefore called IFN-free therapies.

OBJECTIVE

The objective of this study systematic review was to evaluate the efficacy of IFN-free therapies for the treatment of chronic hepatitis C, and thus increase the clinical evidence for these therapies.

METHODS

A systematic review was conducted in accordance with Cochrane Collaboration recommendations. A search was performed in six different electronic databases using 'clinical trials', 'hepatitis C' and 'interferon-free' as the main descriptors, and studies that conformed to the inclusion criteria had their data extracted, including study information, baseline characteristics, and efficacy outcomes (sustained virologic response, rapid virologic response, and virologic failure).

RESULTS

Sixty-four randomized clinical trials including 15 different therapies were included in a total of 15,731 patients infected with the hepatitis C virus, mostly with genotype 1, and mainly treated for 12 or 24 weeks. The sustained virologic response rate after 12 weeks of treatment was approximately 89%, while the virologic failure rate was below 5%.

CONCLUSIONS

Second-generation DAAs presented several advantages: virologic response values higher than the average achieved by previous IFN-based therapies, reduced treatment duration, and the possibility of different combinations of therapies to meet patient needs. Thus, IFN-free therapies appear to be valuable alternatives for the treatment of chronic hepatitis C.

Hepatic Pharmacokinetics and Pharmacodynamics With Ombitasvir/Paritaprevir/Ritonavir Plus Dasabuvir Treatment and Variable Ribavirin Dosage

Background

It is unknown whether ribavirin (RBV) coadministration modifies the early rate of decline of hepatitis C virus (HCV) RNA in the liver versus plasma compartments, specifically.

Methods

This partially randomized, open-label, phase 2 study enrolled treatment-naive, noncirrhotic patients with HCV genotype 1a. Patients were randomized 1:1 into Arms A and B, and then enrolled in Arm C. Patients received ombitasvir/paritaprevir/ritonavir plus dasabuvir for 12 weeks with either: no RBV for the first 2 weeks followed by weight-based dosing thereafter (Arm A), weight-based RBV for all 12 weeks (Arm B), or low-dose RBV (600 mg) once daily for all 12 weeks. Fine needle aspiration (FNA) was used to determine HCV RNA decline within liver.

Results

Baseline HCV RNA was higher and declined more rapidly in plasma than liver; however, RBV dosing did not impact either median plasma or liver HCV RNA decline during the first 2 weeks of treatment. Liver-to-plasma drug concentrations were variable over time. The most common adverse event was pain associated with FNA.

Conclusions

Coadministration of RBV had minimal visible impact on the plasma or liver kinetics of HCV RNA decline during the first 2 weeks of treatment, regardless of RBV dosing.

Twelve weeks of ombitasvir/paritaprevir/r and dasabuvir without ribavirin is effective and safe in the treatment of patients with HCV genotype 1b infection and compensated cirrhosis: results from a real-world cohort study

OBJECTIVE

To explore the effectiveness and safety of ombitasvir/paritaprevir/ritonavir and dasabuvir (OBV/PTV/r+DSV) for 12 weeks without ribavirin in adults with chronic HCV genotype 1b infection and compensated cirrhosis.

METHODS

Observational study of a prospective cohort of adult patients with HCV genotype 1b infection and compensated cirrhosis who received 12 weeks of OBV/PTV/r and DSV without ribavirin. Effectiveness was assessed by recording the percentage of patients achieving sustained virological response at week 12 post-treatment (SVR12). Safety outcomes were based on the incidence of adverse events.

RESULTS

Seventy-eight patients were included. The SVR12 rate was 96.1% (95%CI 89.2-99.2). Adverse events were recorded in 78.0% of patients. Of these, 97.7% were grade 1/2. One patient discontinued treatment prematurely owing to adverse events. Eighty-six interactions were detected in 43 patients (55.1%). Overall, 81.4% of interactions required close monitoring, alteration of drug dosage, or timing of administration. In 7.0% of cases, the interactions arose from contraindications that required the suspension of the concomitant drug. In 11.6% of cases, medicinal plants or foods were withdrawn.

CONCLUSIONS

The simplified regimen of OBV/PTV/r+DSV administered for 12 weeks is effective and safe in patients with chronic HCV genotype 1b infection and compensated cirrhosis. No adverse reactions related to drug-drug interactions were recorded.

Real-world treatment of hepatitis C with second-generation direct-acting antivirals: initial results from a multicentre Canadian retrospective cohort of diverse patients

BACKGROUND

High hepatitis C cure rates have been observed in registration trials with second-generation direct-acting antivirals. Real-world data also indicate high sustained viral response (SVR) rates. Our objective was to determine real-world SVR rates for patients infected with hepatitis C virus (HCV) who were treated with second-generation direct-acting antivirals in the first 18 months of their availability in Canada.

METHODS

Four centres in Calgary contributed their treatment data for a diverse patient population including those who had or had not undergone liver transplantation, those coinfected with HIV and vulnerable populations. We included all patients documented to have started hepatitis C treatment with direct-acting antivirals between October 2014 and April 2016, with follow-up through October 2016. We used multivariate analysis to determine independent predictors of treatment failure.

RESULTS

Outcome data were available for 351 patients, of whom 326 (92.9%) achieved an SVR (193/206 [93.7%], 57/59 [96.6%] and 44/51 [86.3%] for genotypes 1a, 1b and 3, respectively, p = 0.2). Independent predictors of not achieving SVR were older age (adjusted odds ratio [OR] 0.95 [95% confidence interval (CI) 0.90-1.00]), male sex (adjusted OR 0.30 [95% CI 0.10-0.89]) and, in patients with genotype 1a infection, history of hepatocellular carcinoma (adjusted OR 0.13 [95% CI 0.03-0.53]). In the entire cohort, the presence of cirrhosis, genotype and hepatocellular carcinoma were not associated with a lower SVR rate. There were no differences in SVR rate according to treatment centre, HIV coinfection or liver transplantation. Among patients with genotype 3 infection, a significantly lower SVR rate was observed for those treated outside of standard of care than for those treated within standard of care (33.3% v. 89.6%, p = 0.04). De novo hepatocellular carcinoma developed in 12 patients (3.4%) despite successful direct-acting antiviral therapy.

INTERPRETATION

We report high SVR rates in a real-world diverse cohort of HCV-infected patients treated with second-generation direct-acting antivirals. The results highlight the importance of conducting real-world analyses to elucidate clinical factors associated with poorer outcomes that may not be identified in registration trials.

How much of a problem is resistance in treating hepatitis C?

PURPOSE OF REVIEW

Directly acting antiviral drug (DAA) treatments represent a major advance in hepatitis C management, achieving virological cures in excess of 90%. When treatment failure occurs, it is mostly due to relapse with the emergence of resistance-associated variants.

RECENT FINDINGS

Data from in-vitro studies and clinical trials have enabled characterization of the amino acid substitutions in antiviral drug targets that confer reduced susceptibility to DAAs. These resistance-associated substitutions (RASs) may exist prior to treatment, and are associated with, but do not inevitably result in, treatment failure. The most important RASs with current regimens occur in the NS5A protein of viral variants, which may persist for years after treatment. The optimal strategy is to prevent resistance through administering the best treatment, appropriately matched to patient and virological characteristics, for example the presence of cirrhosis, prior exposure to interferon and so on.

SUMMARY

International treatment guidelines have been developed to select treatments, which may vary in duration and coadministration with ribavirin. Routine resistance testing prior to treatment of naive patients is not generally recommended. Next-generation DAAs will further reduce the emergence of RASs and, because of activity against RASs to currently used DAAs, will be used as rescue therapies for patients who have failed treatment.

New hepatitis C virus genotype 1 subtype naturally harbouring resistance-associated mutations to NS5A inhibitors

Hepatitis C virus (HCV) is a highly divergent virus currently classified into seven major genotypes and 86 subtypes (ICTV, June 2017), which can have differing responses to therapy. Accurate genotyping/subtyping using high-resolution HCV subtyping enables confident subtype identification, identifies mixed infections and allows detection of new subtypes. During routine genotyping/subtyping, one sample from an Equatorial Guinea patient could not be classified into any of the subtypes. The complete genomic sequence was compared to reference sequences by phylogenetic and sliding window analysis. Resistance-associated substitutions (RASs) were assessed by deep sequencing. The unclassified HCV genome did not belong to any of the existing genotype 1 (G1) subtypes. Sliding window analysis along the complete genome ruled out recombination phenomena suggesting that it belongs to a new HCV G1 subtype. Two NS5A RASs (L31V+Y93H) were found to be naturally combined in the genome which could limit treatment possibilities in patients infected with this subtype.

The global origins of resistance-associated variants in the non-structural proteins 5A and 5B of the hepatitis C virus

New, costly, fast acting, therapies targeting the non-structural proteins 5A and 5B (NS5A and NS5B) regions of the hepatitis C virus (HCV) genome are curative in the majority of cases. Variants with certain mutations in the NS5A and NS5B regions of HCV have been shown to reduce susceptibility to direct-acting NS5A and NS5B therapy and are found in treatment naïve patients. Despite this, the ease with which these variants evolve is poorly known, as are their evolutionary and geographic origins. To address this crucial gap we inferred the evolutionary and geographic origins of resistance-associated variants (RAVs) in the HCV NS5A and NS5B regions of subtypes 1a, 1b, and 3a sequences available from global databases. We found that RAVs in the NS5A region of HCV, when prevalent, were widely dispersed throughout the phylogenetic tree of HCV with multiple independent origins and that these variants are globally distributed. In contrast, most of the NS5B C316N variants came from one of two clades in the phylogenetic tree of HCV subtype 1b. The presence of serine (S) at codon 218 of HCV NS5B appears to facilitate the evolution of the C316N RAV. Other NS5B RAVs did not arise very frequently in our data set, except for S556G in subtype 1b and with respect to geography NS5B RAVs were also globally distributed. The inferred distribution of RAVs in the NS5A region and frequency of their origin suggest a low fitness barrier without the need for co-evolution of compensatory mutations. A low fitness barrier may allow rapid selection of de novo resistance to NS5A inhibitors during therapy.

Sofosbuvir and velpatasvir with or without voxilaprevir in direct-acting antiviral-naïve chronic hepatitis C: patient-reported outcomes from POLARIS 2 and 3

BACKGROUND

Chronic hepatitis C infection leads to impairment of patient-reported outcomes (PROs). Treatment with direct-acting antiviral regimens results in short- and long-term improvement of these outcomes.

AIM

To assess PROs in patients treated with a newly developed direct-acting antiviral, a fixed-dose combination of sofosbuvir/velpatasvir (SOF/VEL) with/without voxilaprevir (VOX).

METHODS

The PRO data were collected from participants of POLARIS-2 and POLARIS-3 clinical trials (DAA-naïve, all HCV genotypes). Participants self-administered SF-36v2, FACIT-F, CLDQ-HCV and WPAI:SHP instruments at baseline, during treatment, and in follow-up.

RESULTS

Of 1160 patients, 611 received SOF/VEL/VOX and 549 received SOF/VEL (52.8 ± 11.0 years, 55.9% male, 75.4% treatment-naïve, 33.9% cirrhotic). The sustained viral response at 12 weeks (SVR12) rates were 95%-98%. During treatment, improvements in most PRO scores were significant (all but one P < .01) and ranged from, on average, +2.3 to +15.0 points (on a 0-100 scale) by the end of treatment. These improvements were similar between SOF/VEL/VOX and SOF/VEL arms (all P > .05). After treatment discontinuation, patients treated with both regimens achieved significant and clinically meaningful PRO gains (+2.7 to +16.7 by post-treatment week 12, +3.9 to +20.1 by post-treatment week 24; all but one P < .001). Multivariate analysis showed that depression, anxiety and cirrhosis were the most consistent independent predictors of PRO impairment while no association of PROs with the treatment regimen choice was found (all P > .05).

CONCLUSIONS

The pan-genotypic regimens with SOF/VEL with or without VOX not only have excellent efficacy and safety, but also significantly positively impact patients' experience both during treatment and after achieving sustained virologic response in DAA-naïve patients with HCV.

Meta-Analysis of Grazoprevir plus Elbasvir for Treatment of Hepatitis C Virus Genotype 1 Infection

BACKGROUND AND AIM

Grazoprevir is an NS3/4A protease inhibitor (PI), while elbasvir is an NS5A inhibitor. We performed this meta-analysis to directly compare grazoprevir plus elbasvir and ribavirin regimen vs. grazoprevir and elbasvir without ribavirin in the treatment of hepatitis C virus genotype 1 infection and to precisely evaluate the efficacy of the latter regimen in cirrhotic, IL28 CC genotype patients and those coinfected with human immunodeficiency virus.

MATERIAL AND METHODS

A computer literature search of PubMed, Scopus, EBSCO, Embase, and Cochrane central was conducted. Studies were screened for eligibility. Sustained virologic response (SVR) rates were pooled using OpenMeta[Analyst] software for windows. A subgroup analysis was performed to stratify the treatment efficacy according to the different baseline characteristics of HCV patients.

RESULTS

Eight randomized controlled trials (n = 1,297 patients) were pooled in the final analysis. The overall SVR rate was 96.6% with 95% CI [95.5% to 98%]. For cirrhotic patients, the SVR rate was 95.7% with 95% CI [93.9% to 97.5%] and for non-cirrhotic patients, the SVR rate was 97% with 95% CI [95.9% to 98.4%]. Furthermore, the addition of ribavirin (RBV) to the treatment regimen did not significantly improve the SVR (RR 1.003, 95% CI [0.944 to 1.065]). The dual regimen was effective in patient populations with NS3 resistance-associated (RAS). However, this regimen achieved lower SVR rates (< 90%) in patients with NS5A RAS.

CONCLUSIONS

We conclude that the 12-week treatment regimen of the fixed dose combination of grazoprevir plus elbasvir achieved high SVR rates in patients with HCV genotype 1 infection. The addition of ribavirin to this regimen did not add a significant benefit.

Management of Hepatitis C/HIV Coinfection in the Era of Highly Effective Hepatitis C Virus Direct-Acting Antiviral Therapy

The increased life expectancy of persons infected with human immunodeficiency virus (HIV) treated with antiretroviral therapy (ART) has resulted in renewed attention to non-HIV-related diseases exacerbated by HIV infection. Coinfection with hepatitis C virus (HCV) is a particular area of concern, as the global prevalence has been estimated at 2.5-5 million people. In this article, we discuss the epidemiology of HCV infection and reinfection, HCV-related liver disease progression in the era of effective ART, and the efficacy of emerging HCV treatment strategies in persons with HIV/HCV coinfection. New data regarding treatment of persons with HIV/HCV coinfection suggest that HCV treatment should be a priority in those with HIV. Results from recent studies using all-oral HCV regimens have shown high rates of sustained virologic response in both clinical trials and real-world settings. A multidisciplinary approach to HCV treatment in those with HIV is recommended for optimal patient management. Following HCV cure, practitioners also need to be mindful of the risks for HCV reinfection and educate patients on protective measures.

Hepatitis C virus deep sequencing for sub-genotype identification in mixed infections: A real-life experience

•

Routine strategies for hepatitis C virus (HCV) genotyping have several limitations. Deep sequencing methods can solve this problem.

•

Accurate determination of viral genotypes and subtypes would allow optimal patient management and the most effective therapy.

•

Mixed infections may represent a key factor for efficient therapy. Patients infected with more than one HCV genotype (mixed infection) can be detected only by deep sequencing methods.

•

These patients can fail treatment with direct-acting antiviral agents, hence next-generation sequencing methods are highly recommended in clinical practice.

Background

The effectiveness of the new generation of hepatitis C treatments named direct-acting antiviral agents (DAAs) depends on the genotype, subtype, and resistance-associated substitutions present in individual patients. The aim of this study was to evaluate a massive sequencing platform for the analysis of genotypes and subtypes of hepatitis C virus (HCV) in order to optimize therapy.

Methods

A total of 84 patients with hepatitis C were analyzed. The routine genotyping methodology for HCV used at the study institution (Versant HCV Assay, LiPA) was compared with a deep sequencing platform (454/GS-Junior and Illumina MiSeq).

Results

The mean viral load in these HCV patients was 6.89 × 10⁶ ± 7.02 × 10⁵. Viral genotypes analyzed by LiPA were distributed as follows: 26% genotype 1a (22/84), 55% genotype 1b (46/84), 1% genotype 1 (1/84), 2.5% genotype 3 (2/84), 6% genotype 3a (5/84), 6% genotype 4a/c/d (5/84). When analyzed by deep sequencing, the samples were distributed as follows: 27% genotype 1a (23/84), 56% genotype 1b (47/84), 8% genotype 3a (7/84), 5% genotype 4d (4/84), 2.5% genotype 4f (2/84). Six of the 84 patients (7%) were infected with more than one subtype. Among these, 33% (2/6) failed DAA-based triple therapy.

Conclusions

The detection of mixed infection could explain some treatment failures. Accurate determination of viral genotypes and subtypes would allow optimal patient management and improve the effectiveness of DAA therapy.

Pharmacokinetics, Efficacy, and Safety of Hepatitis C Virus Drugs in Patients with Liver and/or Renal Impairment

Hepatitis C virus (HCV)-infected patients often suffer from liver cirrhosis, which can be complicated by renal impairment. Therefore, in this review we describe the treatment possibilities in HCV patients with hepatic and renal impairment. Cirrhosis alters the structure of the liver, which affects drug-metabolizing enzymes and drug transporters. These modifications influence the plasma concentration of substrates of drugs metabolized/transported by these enzymes. The direct-acting antivirals (DAAs) are substrates of, for example, cytochrome P450 enzymes in the liver. Most DAAs are not studied in HCV-infected individuals with decompensated cirrhosis, and therefore awareness is needed when these patients are treated. Most DAAs are contraindicated in cirrhotic patients; however, patients with a Child-Pugh score of B or C can be treated safely with a normal dose sofosbuvir plus ledipasvir or daclatasvir, in combination with ribavirin. Patients with renal impairment (glomerular filtration rate [GFR] <90 mL/min) or who are dependent on dialysis often tolerate ribavirin treatment poorly, even after dose adjustments. However, most DAAs can be used at the normal dose because DAAs are not renally excreted. To date, grazoprevir plus elbasvir is the preferred DAA regimen in patients with renal impairment as data are pending for sofosbuvir patients with GFR <30 mL/min (as for ledipasvir and velpatasvir). However, sofosbuvir has been used in a small number of patients with severe renal impairment and, based on these trials, we recommend sofosbuvir 400 mg every day when no other DAA regimen is available. Ledipasvir and velpatasvir are not recommended in patients with severe renal impairment.

Efficacy and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir with ribavirin for the treatment of HCV genotype 1b compensated cirrhosis in patients aged 70 years or older

Advanced age has been a major limitation of interferon-based treatment for chronic hepatitis C virus (HCV) infection because of its poor response and tolerability. Direct-acting antiviral (DAA) drug regimens are safe and highly effective, allowing administration of treatment also in elderly. This study aims to assess the efficacy and safety of paritaprevir/ritonavir, ombitasvir, and dasabuvir (PrOD) with ribavirin for the treatment of patients aged ≥70 years with HCV genotype 1b compensated cirrhosis.A total of 1008 patients with HCV genotype 1b compensated cirrhosis were prospectively treated with PrOD + ribavirin for 12 weeks, between December 2015 and July 2016. Sustained virologic response 12 weeks after the end of treatment (SVR12), adverse effects (AEs), comorbidities, discontinuation, and death rates were recorded. Efficacy and safety of therapy were assessed in patients aged ≥70 years and compared with data from patients <70 years.There were 117 patients aged ≥70 years, preponderantly females (58.9%), mean age 73.3 ± 2.8 years (range 70-82), and 37 (31.6%) were treatment-experienced. Comorbidities were reported in 60.6% of patients ≥70 years and in 39.8% of those <70 years (P < .001). SVR12 rates based on intention-to-treat and per-protocol analyses were 97.4% and 100%, respectively, in patients ≥70 years, compared to 97.8% and 99.6%, respectively, in patients <70 years (P = ns and P = ns). Severe AEs were reported in 4 (3.4%) patients ≥70 years, compared to 23 (2.6%) in those <70 years (P = ns). One death was recorded in a patient aged 79 years (0.9%) and 6 deaths (0.8%) in those <70 years (P = ns).Treatment with PrOD + ribavirin in patients 70 years of age or older with HCV genotype 1b compensated cirrhosis proved as effective, safe, and well tolerated, as it did in younger patients.

Daclatasvir/asunaprevir/beclabuvir, all-oral, fixed-dose combination for patients with chronic hepatitis C virus genotype 1

BACKGROUND AND AIM

This multinational (Taiwan, South Korea, Russia) phase 3 study evaluated the all-oral, ribavirin-free, fixed-dose combination (DCV-TRIO) of daclatasvir (NS5A inhibitor) 30 mg, asunaprevir (NS3 inhibitor) 200 mg, and beclabuvir (NS5B inhibitor) 75 mg, in patients with chronic hepatitis C virus genotype-1 infection, with or without compensated cirrhosis.

METHODS

UNITY-4 (NCT02170727) was an open-label, two-cohort study in which 169 patients, treatment-naive (n = 138) or treatment-experienced (n = 31), received twice-daily DCV-TRIO for 12 weeks with 24 weeks of post-treatment follow-up. The primary efficacy end point was sustained virologic response at post-treatment week 12 (SVR12) in treatment-naive patients.

RESULTS

Eighty-eight (52%) patients were men, 81 (48%) Taiwanese, 78 (46%) Korean, and 10 (6%) Russian; 23 (14%) had compensated cirrhosis, and 52 (31%) were IL28B (rs1297860) non-CC genotype. Baseline resistance-associated NS5A polymorphisms (L31 and/or Y93) were detected in 25/165 (15%) patients with available genotype-1 sequencing data. SVR12 was achieved by 98.6% (136/138; 95% confidence interval: 94.9-99.8%) of treatment-naive and 100% (31/31; 95% confidence interval: 88.8-100%) of treatment-experienced patients. Both virologic failures were found to be infected with hepatitis C virus genotype-6g; 100% SVR12 was observed for genotype-1a (n = 8) and genotype-1b (n = 157). Two patients experienced serious adverse events. Eight (5%) patients experienced reversible grade 3/4 alanine aminotransferase or aspartate aminotransferase elevations, leading to discontinuation in four (2%); all achieved SVR12. There were no grade 3/4 total bilirubin increases and no deaths.

CONCLUSIONS

Twelve weeks of DCV-TRIO was well tolerated and provided 100% SVR12 in treatment-naive and treatment-experienced patients with genotype-1 infection, with or without cirrhosis, including those with baseline NS5A-L31 or NS5A-Y93 resistance-associated substitutions.

Sofosbuvir and daclatasvir plus ribavirin treatment improve liver function parameters and clinical outcomes in Egyptian chronic hepatitis C patients

BACKGROUND AND AIMS

Interferon-free direct-acting antivirals (DAA) combination therapies, including sofosbuvir (SOF) and daclatasvir (DCV) therapy, eradicate chronic hepatitis C virus (HCV) in a high percentage of patients, but its impact on improvements in liver function is unclear. The aim of this study was to investigate the changes in clinical and biochemical parameters reflecting liver function and general status in those who achieved HCV eradication by DAA.

PATIENTS AND METHODS

From March 2016 to October 2016, 374 chronic hepatitis C patients were enrolled for this prospective, observational study and received SOF, DCV with ribavirin, to evaluate the changes in liver function parameters, international normalized ratio, complete blood count, model for end-stage liver disease, and Child-Turcotte-Pugh scores after achieving a sustained virological response 12 weeks after treatment.

RESULTS

In those who achieved HCV clearance, liver function parameters, serum albumin, bilirubin, platelet count, and international normalized ratio improved significantly in the majority of patients; the reduction in the model for end-stage liver disease score was (-2.36, SE 0.15, P<0.001). 44% of the patients showed an improved Child-Turcotte-Pugh score, 51% showed no change, and only 5% showed deterioration.

CONCLUSION

Successful HCV eradication by DAAs including SOF, DCV with ribavirin therapy improved liver function parameters and clinical outcomes in chronic hepatitis C patients.

Efficacy and safety of ombitasvir/paritaprevir/ritonavir in dialysis patients with genotype 1b chronic hepatitis C

AIM

From a pharmacokinetic viewpoint, the use of ombitasvir/paritaprevir/ritonavir, one of the standards of care for genotype 1b chronic hepatitis C in Japan, could be possible in patients with impaired renal function. The aim of this study was to assess the efficacy and safety of this combination that have not yet been addressed in patients undergoing dialysis.

METHODS

A retrospective, multicenter study evaluated the outcome of 12-week ombitasvir (non-structural protein [NS]5A inhibitor)/paritaprevir (NS3/4A protease inhibitor)/ritonavir combination therapy for dialysis patients. The primary end-point was sustained virologic response 12 weeks after therapy (SVR12).

RESULTS

The subjects were 31 patients with a median age of 64 years (range, 49-85 years), including 10 cirrhotic patients. All of the 31 patients had an estimated glomerular filtration rate level <15 mL/min/1.73 m² , defined as end-stage renal disease (ESRD). Pre-existing resistance-associated substitutions at position L31 and Y93 of the NS5A region were detected in 0% and 3.6% (1/28), respectively. The rates of rapid virologic response, end-of-treatment response, and SVR12 were 93.5% (29/31), 100% (31/31), and 96.8% (30/31), respectively. The incidence of adverse events was 35.5% (11/31). Of the 11 patients, one discontinued the treatment due to erythema multiforme and thereafter relapsed. The most frequent adverse event was pruritus (6.5%; 2/31).

CONCLUSIONS

The present study suggests that ombitasvir/paritaprevir/ritonavir combination therapy is effective and safe for genotype 1b chronic hepatitis C patients undergoing dialysis due to ESRD.

Hepatocellular carcinoma risk following direct-acting antiviral HCV therapy: A systematic review, meta-analyses, and meta-regression

BACKGROUND & AIMS

The risk of hepatocellular carcinoma (HCC) occurrence or recurrence following direct-acting antiviral (DAA) hepatitis C virus (HCV) therapy remains unclear. The aims of this study were to compare the rate of HCC occurrence in patients with HCV-related cirrhosis, following DAA vs. interferon (IFN)-based cure, and to compare the rate of HCC recurrence in patients who received curative HCC treatment, following DAA vs. IFN-based cure.

METHODS

A search was conducted for reports published between January 2000 and February 2017. Studies were included if they assessed HCC outcomes by type and response to HCV therapy. Random-effects meta-analyses were undertaken to determine a combined estimate of HCC incidence rate per 100/person-years (py) among patients with a sustained virological response (SVR).

RESULTS

A total of 41 studies (n=13,875 patients), including 26 on HCC occurrence (IFN=17, DAA=9; prospective=19, retrospective=5, retrospective-prospective=2), and 17 on HCC recurrence (IFN=7, DAA=10; prospective=11, retrospective=5 and retrospective-prospective=1) were included. In studies assessing HCC occurrence, average follow-up was shorter (1.0 vs. 5.5years), and average age older (60 vs. 52years) in DAA studies. In studies assessing HCC recurrence, average follow-up was shorter (1.3 vs. 5.0years), but average age similar (64 vs. 66years) in DAA studies. HCC occurrence was 1.14/100 py (95% CI 0.86-1.52) and 2.96/100 py (95% CI 1.76-4.96) in IFN and DAA studies respectively. HCC recurrence was 9.21/100 py (95% CI 7.18-11.81) and 12.16/100 py (95% CI 5.00-29.58) in IFN and DAA studies respectively. In meta-regression adjusting for study follow-up and age, DAA therapy was not associated with higher HCC occurrence (RR 0.68; 95% CI 0.18-2.55; p=0.55) or recurrence (RR 0.62, 95% CI 0.11-3.45, p=0.56).

CONCLUSION

There is no evidence for differential HCC occurrence or recurrence risk following SVR from DAA and IFN-based therapy.

LAY SUMMARY

The risk of hepatocellular carcinoma (HCC) occurrence or recurrence following direct-acting antiviral (DAA) hepatitis C virus (HCV) therapy remains unclear. We conducted a meta-analysis to compare occurrence and recurrence of HCC in patients receiving either DAA or interferon (IFN) therapy. There is no evidence that HCC occurrence or recurrence is different between patients receiving DAA or IFN therapy.

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).

Pharmacokinetics of Tacrolimus and Cyclosporine in Liver Transplant Recipients Receiving 3 Direct-Acting Antivirals as Treatment for Hepatitis C Infection

BACKGROUND

Interactions between tacrolimus and cyclosporine (CSA) and the 3 direct-acting antiviral regimen (3D) of ombitasvir, paritaprevir/ritonavir, and dasabuvir necessitate a priori dose adjustments for the immunosuppressants to achieve desired levels. Modeling and simulations based on data in healthy subjects predicted that tacrolimus 0.5 mg every 7 days or 0.2 mg every 3 days, and CSA at one-fifth the total daily dose administered once daily, would achieve desired trough concentrations (Ctrough) during 3D treatment. The success of these dosing recommendations was evaluated by analyzing pharmacokinetic data from liver transplant recipients in the CORAL-I study.

METHODS

A population pharmacokinetic model was developed using tacrolimus dosing and Ctrough data before and during 3D treatment (n = 29). The model was used to simulate various tacrolimus dosing regimens and predict tacrolimus concentration-time profiles during 3D treatment. CSA Ctrough data before and during 3D treatment (n = 5) were also summarized.

RESULTS

A one-compartment model with first-order absorption adequately described tacrolimus pharmacokinetic profiles during the first 4 weeks of 3D treatment. Estimated tacrolimus Ctrough values (median; interquartile range) before and during 3D treatment were comparable (5.7 ng/mL; 4.9-6.5 ng/mL versus 5.2 ng/mL; 4.2-6.3 ng/mL, respectively). Based on simulations, in a patient with a starting Ctrough of 6 ng/mL, 0.5 mg tacrolimus every 7 or 14 days or 0.2 mg tacrolimus every 3 days will result in Ctrough levels of 6-9 ng/mL, 4-6 ng/mL, and 6-10 ng/mL, respectively, during 3D treatment. For CSA, Ctrough values (median; interquartile range) before and during 3D treatment were comparable (126 ng/mL; 94-140 ng/mL versus 104 ng/mL; 82-140 ng/mL).

CONCLUSIONS

Observed data for tacrolimus and CSA in liver transplant recipients confirm that the recommended dosing strategies are valid and therapeutic levels of immunosuppression can be maintained during 3D treatment.

Pharmacokinetics and Tolerability of Anti-Hepatitis C Virus Treatment with Ombitasvir, Paritaprevir, Ritonavir, with or Without Dasabuvir, in Subjects with Renal Impairment

BACKGROUND

The direct-acting antiviral agent (DAA) combination of ombitasvir and paritaprevir (administered with ritonavir) with (3D regimen) or without (2D regimen) dasabuvir has shown very high efficacy rates in the treatment of chronic hepatitis C virus (HCV) infection. Renal impairment, a common comorbidity in patients with chronic HCV infection, can influence the pharmacokinetics of antiviral agents and hence their efficacy and safety profiles.

OBJECTIVE

The aim of this study was to evaluate the influence of renal impairment on the pharmacokinetics and tolerability of the 3D and 2D regimens.

METHODS

Overall, 24 subjects, six in each of four renal function groups (normal, mild, moderate, and severe), received a single dose of the 3D and 2D regimens in separate dosing periods. Plasma and urine were analyzed to assess the effect of renal impairment on drug exposure.

RESULTS

DAA exposures changed by up to 21, 37, and 50 % in subjects with mild, moderate, and severe renal impairment, respectively, versus subjects with normal renal function. Ritonavir exposure increased with the degree of renal impairment (maximum 114 %). The half-lives of DAAs and ritonavir in subjects with renal impairment were generally comparable with those in healthy subjects. No safety or tolerability concerns arose in this study.

CONCLUSION

The 3D and 2D regimens do not require dose adjustment for patients with HCV infection and concomitant renal impairment.

Current and future challenges in HCV: insights from an Italian experts panel

BACKGROUND

The recent availability of direct acting antiviral drugs (DAAs) has drastically changed hepatitis C virus (HCV) treatment scenarios, due to the exceedingly high rates of sustained virological response (SVR) and excellent tolerability allowing for treatment at all disease stages.

METHODS

A panel of Italian experts was convened twice, in November 2016 and January 2017, to provide further support on some open issues and provide guidance for personalized HCV care, also in light of forthcoming regimens.

RESULTS AND CONCLUSIONS

Treatment recommendations issued by international and national liver societies to guide clinicians in the management of HCV infection are constantly updated due to accumulating new data. Such recommendations may not be applicable to all healthcare settings for a variety of reasons. Moreover, some gaps still remain and the spectrum of patients to be treated is also evolving.

Effects of All-Oral Anti-Viral Therapy on HVPG and Systemic Hemodynamics in Patients With Hepatitis C Virus-Associated Cirrhosis

BACKGROUND & AIMS

Patients with hepatitis C virus-associated cirrhosis and clinical significant portal hypertension (CSPH, hepatic venous pressure gradient [HVPG] 10 mmHg or greater), despite achieving sustained virological response (SVR) to therapy, remain at risk of liver decompensation. We investigated hemodynamic changes following SVR in patients with CSPH and whether liver stiffness measurements (LSMs) can rule out the presence of CSPH.

METHODS

We performed a multicenter prospective study of 226 patients with hepatitis C virus-associated cirrhosis and CSPH who had SVR to interferon-free therapy at 6 Liver Units in Spain. The portal pressure gradient was determined based on HVPG at baseline and 24 weeks after therapy; patients also underwent right-heart catheterization and LSM at these time points. Primary outcomes were effects of SVR on the hepatic, pulmonary, and systemic hemodynamics; factors related to HVPG ≥10% reduction and to CSPH persistence; and whether LSMs can rule out the presence of CSPH after SVR.

RESULTS

Most patients (75%) had esophageal varices, 21% were Child-B, and 29% had at least 1 previous episode of liver decompensation. Overall, HVPG decreased from 15 (IQR: 12-18) before treatment to 13 (10-16) mmHg after SVR (reduction of 2.1 ± 3.2 mmHg; P < .01). However, CSPH persisted in 78% of patients. HVPG decreased by 10% or more from baseline in 140 patients (62%). Baseline level of albumin below 3.5 g/dL was the only negative factor associated with an HVPG reduction of 10% or more. LSM decreased from 27 (20-37) kPa before treatment to 18 (14-28) kPa after SVR (P < .05). One third of patients with a reduction in LSM to below 13.6 kPa after SVR still had CSPH. A higher baseline HVPG and a lower decrease in LSM after treatment were associated with persistence of CSPH after SVR. Systemic hemodynamics improved after SVR. Interestingly, pulmonary hypertension was present in 13 patients at baseline and 25 after SVR, although only 3 patients had increased pulmonary resistance.

CONCLUSIONS

In a multicenter prospective study of patients with hepatitis C virus-associated cirrhosis, an SVR to all-oral therapy significantly reduced HVPG, compared with before treatment. Nevertheless, CSPH persists in most patients despite SVR, indicating persistent risk of decompensation. In this population, changes in LSM do not correlate with HVPG and cut-off values are not reliable in ruling out CSPH after SVR.

Real-world effectiveness of ombitasvir/paritaprevir/ritonavir±dasabuvir±ribavirin in patients with hepatitis C virus genotype 1 or 4 infection: A meta-analysis

The direct-acting antiviral regimen of ombitasvir (OBV)/paritaprevir (PTV)/ritonavir (r)±dasabuvir (DSV)±ribavirin (RBV) demonstrated high rates of sustained viral response at post-treatment week 12 (SVR12) in clinical trials for treatment of hepatitis C virus (HCV) genotypes (GT) 1 and 4. To confirm the effectiveness of this regimen in the real world, we conducted meta-analyses of published literature on 30 April 2016. Freeman-Tukey transformation determined the SVR rate within GTs 1a, 1b and 4, as well as specific SVR rates by cirrhosis or prior treatment experience status. Rates of virologic relapse, hepatic decompensation, drug discontinuation and serious adverse events were also analysed. In total, 20 cohorts across 12 countries were identified, totalling 5158 patients. The overall SVR12 rates were 96.8% (95% CI 95.8-97.7) for GT1 and 98.9% (95% CI 94.2-100) for GT4. For GT1a patients, the SVR rates were 94% and 97% for those with or without cirrhosis, and 94% overall. For GT1b patients, the SVR rates were 98% and 99% for those with or without cirrhosis, and 98% overall. The virologic relapse rate of GT1 patients was 1.3%, across 3524 patients in nine studies that reported this parameter. The rate of hepatic decompensation was less than 1% across five studies, including 3440 patients, 70% of which had cirrhosis.

CONCLUSIONS

Real-world SVR12 rates for OBV/PTV/r±DSV±RBV were consistently high across HCV GT1 and four irrespective of cirrhosis status or prior HCV treatment experience, confirming effectiveness within a diverse patient population across multiple cohorts and countries.

Safety and Efficacy of Ombitasvir/Paritaprevir/Ritonavir and Dasabuvir with or without Ribavirin for Treatment of Hepatitis C Virus Genotype 1: A Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Interferon-free regimens are rapidly evolving for patients with chronic hepatitis C virus (HCV) infection. We performed this meta-analysis to investigate the safety and efficacy of a combination regimen (ombitasvir [OBV]/paritaprevir [PTV]/ritonavir [r] ± dasabuvir [DSV]) for the treatment of patients with HCV genotype 1 infection.

METHODS

A computerized literature search for relevant clinical trials was conducted during May 2017. Data on sustained virological response (SVR), virological relapse, and safety outcomes were extracted and calculated as pooled proportion (PP) or risk ratio (RR) with their 95% confidence interval (CI), using StatsDirect and RevMan software.

RESULTS

The final analysis included 13 studies for HCV genotype 1 (3115 patients). The pooled effect estimate showed that 12-week treatment of genotype 1 patients with the OBV/PTV/r regimen achieved a high SVR rate (PP = 94%, 95% CI 92-96) that increased to (PP = 97%, 95% CI 96-98) upon the addition of DSV. These results were consistent when independent subgroup analyses were conducted based on viral subgenotypes, the presence of cirrhosis, or former treatment failure. Adding ribavirin (RBV) to this regimen was not associated with increased SVR rates (risk ratio = 1, 95% CI 0.98-1.02), while it increased the risk of serious adverse events (p = 0.02), insomnia (p = 0.001), and pruritus (p < 0.001).

CONCLUSION

The current meta-analysis showed a high efficacy for the OBV/PTV/r regimen in the treatment of HCV genotype 1 (with DSV) infection, regardless of the presence of cirrhosis or former treatment failure. Adding RBV to this regimen slightly decreased the relapse rate. Future studies with larger sample sizes are required to investigate the efficacy of this regimen in other HCV genotypes and to establish the evidence about the effect of adding RBV to OBV/PTV/r + DSV.

Recommendations for the treatment of hepatitis C virus infection in chronic kidney disease: a position statement by the Spanish association of the liver and the kidney

Hepatitis C virus (HCV) infection is one of the main causes of liver cirrhosis worldwide. The long-term impact of HCV infection is highly variable, ranging from minimal histological changes to extensive fibrosis with hepatocellular carcinoma. The development of HCV drugs has increased dramatically in recent years, even in special populations such as chronic kidney disease patients. Classical treatment of chronic hepatitis C was based on the administration of interferon and ribavirin for 24-48 weeks, which was associated with a poor viral response and a high rate of side effects, especially in patients with a lower estimated glomerular filtration rate. The current high availability of the new direct-acting antivirals renders the classification of these agents for this special population necessary. The Spanish Association of the Liver and the Kidney has produced a position statement on the treatment of HCV infection in chronic kidney disease patients since the evidence to guide this treatment is scant and what evidence does exist is weak. The recommendations are based on the results of clinical trials and controlled studies conducted to date, with data published hitherto by the authors of these studies. Since the indications for treatment have been evaluated by other societies or are dependent on internal clinical protocols, the main goal of this position statement is to assist in decision-making when choosing a therapeutic option.

Dose- and Formulation-Dependent Non-Linear Pharmacokinetic Model of Paritaprevir, a Protease Inhibitor for the Treatment of Hepatitis C Virus Infection: Combined Analysis from 12 Phase I Studies

BACKGROUND AND OBJECTIVES

Paritaprevir is a direct-acting antiviral agent that is a component of approved multidrug regimens used in the treatment of hepatitis C virus (HCV) infection. A population pharmacokinetic model for paritaprevir was developed using data from formulation, bioavailability, and drug-drug interaction studies that evaluated the pharmacokinetics of paritaprevir (coadministered with ritonavir to enhance exposure) with or without ombitasvir and/or dasabuvir at different paritaprevir dose levels.

METHODS

A non-linear mixed-effects modeling approach was applied to data from 12 phase I, single- and multiple-dose studies that enrolled a total of 369 healthy volunteers. Age, sex, race, ethnicity, body weight, body surface area, body mass index, and baseline creatinine clearance were evaluated as covariates during model development. In addition, the influences of dose, formulation, and concomitant medications (e.g. ombitasvir and dasabuvir) on paritaprevir bioavailability were included in the model.

RESULTS

A two-compartment model with first-order absorption and elimination optimally described paritaprevir plasma concentration-time data. Paritaprevir bioavailability was formulation- and dose-dependent, and increased supraproportionally. The accumulation of paritaprevir was 1.57-fold on repeated dosing compared with the first dose. Coadministration of dasabuvir increased paritaprevir bioavailability by 59 %; however, ombitasvir coadministration did not affect the pharmacokinetic profile of paritaprevir. No subject-specific covariate influenced the paritaprevir pharmacokinetics. The pharmacokinetic model was robust in bootstrap evaluations and was consistent with observed data based on diagnostic goodness-of-fit plots and visual predictive checks.

CONCLUSION

The complex pharmacokinetics of paritaprevir were well described by the model, which can be used as a basis for clinical trial dosing and further evaluations in patients with HCV.

Drug-Drug Interactions Between the Anti-Hepatitis C Virus 3D Regimen of Ombitasvir, Paritaprevir/Ritonavir, and Dasabuvir and Eight Commonly Used Medications in Healthy Volunteers

Background and Aims

The three direct-acting antiviral regimen of ombitasvir/paritaprevir/ritonavir and dasabuvir (3D regimen) is approved for treatment of hepatitis C virus (HCV) genotype 1 infection. Drug–drug interaction (DDI) studies of the 3D regimen and commonly used medications were conducted in healthy volunteers to provide information on coadministering these medications with or without dose adjustments.

Methods

Three phase I studies evaluated DDIs between the 3D regimen (ombitasvir/paritaprevir/ritonavir 25/150/100 mg once daily + dasabuvir 250 mg twice daily) and hydrocodone bitartrate/acetaminophen (5/300 mg), metformin hydrochloride (500 mg), diazepam (2 mg), cyclobenzaprine hydrochloride (5 mg), carisoprodol (250 mg), or sulfamethoxazole/trimethoprim (SMZ/TMP) (800/160 mg twice daily), all administered orally. DDI magnitude was determined using geometric mean ratios and 90 % confidence intervals for the maximum plasma concentration (C_max) and area under the plasma concentration–time curve (AUC).

Results

Changes in exposures (C_max and AUC geometric mean ratios) of acetaminophen, metformin, sulfamethoxazole, trimethoprim, and diazepam were ≤25 % upon coadministration with the 3D regimen. The C_max and AUC of nordiazepam, an active metabolite of diazepam, increased by 10 % and decreased by 44 %, respectively. Exposures of cyclobenzaprine and carisoprodol decreased by ≤40 and ≤46 %, respectively, whereas exposures of hydrocodone increased up to 90 %. Ombitasvir, paritaprevir, ritonavir, and dasabuvir exposures changed by ≤25 %, except for a 37 % decrease in paritaprevir C_max with metformin and a 33 % increase in dasabuvir AUC with SMZ/TMP.

Conclusions

Acetaminophen, metformin, sulfamethoxazole, and trimethoprim can be coadministered with the 3D regimen without dose adjustment. Higher doses may be needed for diazepam, cyclobenzaprine, and carisoprodol based on clinical monitoring. A 50 % lower dose and/or clinical monitoring should be considered for hydrocodone. No dose adjustment is necessary for the 3D regimen.

Direct antiviral agents (DAAs) - A new age in the treatment of hepatitis C virus infection

Hepatitis C virus (HCV) is a global health problem, because infection frequently leads to chronic hepatitis C eventually progressing to liver cirrhosis and liver cancer. Improved insights into the HCV replication cycle and the role of HCV non-structural proteins have recently enabled to identify drugs directly acting on specific HCV target structures. Agents from three drug classes have been developed and approved by the health authorities. Combinations of two or more drugs from different classes achieve high (>90%) HCV clearance rates and are well tolerated. This interferon-free DAA (direct antiviral agent) therapy has revolutionized antiviral therapy in hepatitis C so that successful hepatitis C treatment can be offered to virtually all patients irrespective of their co-morbidity. This review provides an overview over currently approved regimens and outlines their use in clinical practice. In addition potential short-comings of the current therapeutic options such as drug-drug interactions and selection of viral resistance are addressed. DAA combination therapy has the potential to obtain global control over hepatitis C. However, easy access to DAAs, availability of reliable HCV diagnostics, and affordable costs remain still important goals, which must be reached to globally eliminate hepatitis C.

Safety of the 2D/3D direct-acting antiviral regimen in HCV-induced Child-Pugh A cirrhosis - A pooled analysis

BACKGROUND & AIMS

Chronic hepatitis C virus (HCV)-infected patients with cirrhosis are a high-priority population for treatment. To help inform the benefit-risk profile of the all-oral direct-acting antiviral (DAA) combination regimen of ombitasvir, paritaprevir, and ritonavir, with or without dasabuvir (OBV/PTV/r±DSV) in patients with Child-Pugh A cirrhosis, we undertook a comprehensive review of AbbVie-sponsored clinical trials enrolling patients with Child-Pugh A cirrhosis.

METHODS

Twelve phase II or III clinical trials of the 2-DAA regimen of OBV/PTV/r±ribavirin (RBV) or the 3-DAA regimen of OBV/PTV/r+DSV±RBV that included patients with Child-Pugh A cirrhosis were reviewed; patients who completed treatment by November 16, 2015 were included in a pooled, post hoc safety assessment. The number and percentage of patients with treatment-emergent adverse events (TEAEs), serious TEAEs, and TEAEs consistent with hepatic decompensation were reported.

RESULTS

In 1,066 patients with Child-Pugh A cirrhosis, rates of serious TEAEs and TEAEs leading to study drug discontinuation were 5.3% (95% confidence interval [CI]: 4.1-6.8) and 2.2% (95% CI: 1.4-3.2), respectively. Thirteen patients (1.2%; 95% CI: 0.7-2.1) had a TEAE that was consistent with hepatic decompensation. The most frequent TEAEs consistent with hepatic decompensation were ascites (n=8), esophageal variceal hemorrhage (n=4), and hepatic encephalopathy (n=2).

CONCLUSIONS

This pooled analysis in 1,066 HCV-infected patients with Child-Pugh A cirrhosis confirms the safety of OBV/PTV/r±DSV±RBV in this population. These results support the use of OBV/PTV/r±DSV±RBV in this high-priority population. Lay summary: This pooled safety analysis in 1,066 HCV-infected patients with compensated cirrhosis, receiving treatment with ombitasvir, paritaprevir, and ritonavir with or without dasabuvir, with or without ribavirin, shows that the rate of hepatic decompensation events was similar to previously reported rates in untreated patients.

No one size fits all-Shortening duration of therapy with direct-acting antivirals for hepatitis C genotype 1 infection

The advent of shorter duration, highly effective and well-tolerated interferon-free therapy now provides an opportunity for virtually all HCV-infected individuals to be cured. However, there continues to be a need to simplify and shorten treatment duration. Shortening therapy to 8 weeks with sofosbuvir and ledipasvir can be considered in treatment patients with HCV genotype 1 infection and low baseline viral load. A number of other 8-week dual and triple therapy direct-acting antiviral (DAA) regimens are in advanced clinical development. Several small studies have further demonstrated the feasibility of 6 weeks of sofosbuvir therapy in combination with an NS5A inhibitor and a protease inhibitor for HCV genotype 1. Four weeks of therapy with various combinations of the currently available DAAs appears to be suboptimal with poor response rates observed in phase 2 trials. Response-guided therapy is another promising tool that may allow for shorter therapy but require further research. Shortening therapy and retreating relapsers may be a viable cost-saving measure, but requires further cost-benefit analysis and more data on the impact of resistance on retreatment options.

Real-world experience with the all-oral, interferon-free regimen of ombitasvir/paritaprevir/ritonavir and dasabuvir for the treatment of chronic hepatitis C virus infection in the German Hepatitis C Registry

Real-world studies are relevant to complement clinical trials on novel antiviral therapies against chronic hepatitis C; however, clinical practice data are currently limited. This study investigated effectiveness and safety of ombitasvir/paritaprevir/ritonavir (OBV/PTV/r)±dasabuvir (DSV)±ribavirin (RBV) for treatment of HCV genotype (GT) 1 and GT4 infection in a large real-world cohort. The German Hepatitis C Registry is an observational cohort study prospectively collecting clinical practice data on direct-acting antiviral therapies. Patients with GT1/4 infection treated with OBV/PTV/r±DSV±RBV were analysed. Effectiveness was assessed by sustained virologic response in 558 patients who reached post-treatment week 12 (SVR12). Safety is reported in 1017 patients who initiated treatment. Of the patients, 892 (88%) had GT1 and 125 (12%) had GT4 infection. Prior treatment experience and cirrhosis were reported in 598 (59%) and 228 (22%) patients, respectively. Overall, SVR12 (mITT) was 96% (486/505) in GT1- and 100% (53/53) in GT4 patients. SVR12 rates were high across subgroups including patients with cirrhosis (95%, 123/129), patients with moderate to severe renal impairment (100%, 34/34), and subgroups excluded from registrational trials like patients ≥70 years (96%, 64/67) and failures to prior protease inhibitor treatment (96%, 46/48). Adverse events (AEs) and serious AEs were reported in 52% (525/1017) and 2% (21/1017) of patients, respectively, and led to treatment discontinuation in 1.5% (15/1017) of patients. OBV/PTV/r±DSV±RBV was effective and generally well tolerated for treatment of HCV infection in clinical practice.