Faculty Bibliography

BACKGROUND & AIMS: The best regimen to re-treat patients who do not respond to direct-acting antivirals (DAAs) and the feasibility of further shortening regimens is unclear. We assessed the efficacy and safety of the combination of the nucleotide polymerase inhibitor sofosbuvir, the NS5A inhibitor velpatasvir, and the NS3/4A protease inhibitor GS-9857 in patients with hepatitis C virus genotype 1 infection. METHODS: We performed an open-label trial at 32 sites in the United States and at 2 sites in New Zealand of 197 patients with genotype 1 hepatitis C virus infection, with or without compensated cirrhosis, who were treatment-naive or were treated previously with a DAA. Between March 2, 2015, and September 1, 2015, patients received sofosbuvir-velpatasvir (400 mg/100 mg in a fixed-dose combination) plus GS-9857 (100 mg) once daily for 6-12 weeks, plus ribavirin for 1 treatment group consisting of treatment-naive patients with cirrhosis. The primary end point was sustained virologic response 12 weeks after treatment (SVR12). RESULTS: Among treatment-naive patients without cirrhosis, 71% (24 of 34; 95% confidence interval [CI], 53-85) achieved SVR12 after 6 weeks of treatment and 100% (36 of 36; 95% CI, 90%-100%) achieved SVR12 after 8 weeks of treatment. Among treatment-naive patients with cirrhosis, 94% (31 of 33; 95% CI, 80-99) achieved SVR12 after 8 weeks of treatment and 81% (25 of 31; 95% CI, 63-93) achieved SVR12 after 8 weeks of treatment with ribavirin. Among DAA-experienced patients treated for 12 weeks, 100% without cirrhosis (31 of 31; 95% CI, 89-100) and 100% with cirrhosis (32 of 32; 95% CI, 89-100) achieved SVR12. The most common adverse events were headache, diarrhea, fatigue, and nausea. One patient (<1%) discontinued treatment because of adverse events. CONCLUSIONS: In a phase 2 open-label trial, we found 8 weeks of treatment with sofosbuvir-velpatasvir plus GS-9857 to be safe and effective in treatment-naive patients; 12 weeks was safe and effective in patients previously treated with DAAs. The combination was safe and effective in patients with or without compensated cirrhosis. Clinicaltrials.gov no: NCT02378935.

With an estimated prevalence of about 170 million people worldwide, chronic hepatitis C is an important cause of chronic liver disease associated with a substantial risk of cirrhosis and hepatocellular carcinoma. The recent past has borne witness to remarkable advancements in the treatment of chronic hepatitis C with the development of novel, effective, and well tolerated medications that have resulted in paradigm shifts in treatment approaches and may potentially affect the natural history of the disease. We provide a clinical review of current concepts and future developments in the management of chronic hepatitis C to aid in the understanding and individualization of chronic hepatitis C treatment. J. Med. Virol. 88:1844-1855, 2016. (c) 2016 Wiley Periodicals, Inc.

The US Food and Drug Administration has now approved 10 direct-acting antivirals (DAAs) for the management of hepatitis C virus (HCV). These therapies are combined into 6 regimens that are given for varying durations, with or without ribavirin, depending on the viral genotype, the presence or absence of baseline resistance-associated variants (RAVs), and the patient type. RAVs may be present before exposure to a drug or may become detectable de novo during exposure to a drug. Emerging resistant strains are the most common cause of failure of HCV DAA regimens. Second-generation DAAs provide superior coverage of resistant variants compared with first-generation members of that class. They may also cover a broader range of viral genotypes. Numerous clinical trials have evaluated the safety and efficacy of DAAs in a variety of patient populations, including those with cirrhosis, HIV, and end-stage renal disease. This article evaluates the data from these studies, and discusses recommendations from the American Association for the Study of Liver Diseases (AASLD) and the Infectious Diseases Society of America (IDSA) guidance document.

GS-9190 is a NS5B non-nucleoside analogue with demonstrated effectiveness in a Phase 1 monotherapy study and in combination with other DAAs for treatment of chronic HCV infection. Here, the resistance profile of GS-9190 monotherapy in a Phase 1b study was investigated. Resistance analysis was performed by population sequencing and allele-specific PCR (AS-PCR) for Y448H with an assay cut-off of 0.5%. Phenotypic susceptibility analyses were performed on patient isolates as well as site-directed mutagenesis of mutations selected during monotherapy. No resistance-associated variants were observed in patients before or after receiving single doses of GS-9190 by population sequencing. In contrast, in patients who received GS-9190 for 8 days, mutations Y448H and Y452H in NS5B were observed by population sequencing in 21/36 (58%) and 2/36 (5.6%) patients, respectively, at Day 8 or Day 14. Among the remaining 15 patients who had no detectable Y448H at Day 8 or Day 14 by population sequencing, low frequencies of Y448H ranging from 1.3 to 9.7% were detected in 14 of 15 patients by AS-PCR. By AS-PCR, Y448H remained detectable at reduced frequency in the majority of patients analysed through 4-6 months of follow-up. Chimeric HCV replicons constructed with the NS5B sequence from patients with Y448H and Y448H + Y452H/Y demonstrated 27-fold and 78.5-fold reduced susceptibility to GS-9190. In conclusion, Y448H was rapidly selected in the majority of patients receiving multiple doses of GS-9190 as monotherapy, despite undetectable levels in pretreatment samples. Y448H confers reduced susceptibility to GS-9190 and other NNIs and persisted in most patients for months post-treatment.

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.

BACKGROUND & AIMS: HCV Council 2014, like its predecessor HCV Council 2011, assembled leading clinicians and researchers in the field of hepatitis C to critically evaluate current data regarding best practices for managing patients with chronic hepatitis C virus (HCV). METHODS: Clinical practice statements were developed that reflect the areas of potential controversy with high clinical impact. Faculty members were responsible for reviewing the literature to support or reject these statements. After a review and comprehensive discussion of the data, the HCV Council faculty voted on the nature of the evidence and the level of support for each statement. RESULTS: The results of the detailed analysis with expert opinion are summarized in this article. CONCLUSION: Numerous questions regarding optimal management of certain populations and clinical scenarios remain unanswered. The discussion in the article provides a summary of evidenced-based expert opinion that may help guide clinicians as additional information is developed.

Hepatitis C virus (HCV) uniquely requires the liver-specific microRNA-122 for replication, yet global effects on endogenous miRNA targets during infection are unexplored. Here, high-throughput sequencing and crosslinking immunoprecipitation (HITS-CLIP) experiments of human Argonaute (AGO) during HCV infection showed robust AGO binding on the HCV 5'UTR at known and predicted miR-122 sites. On the human transcriptome, we observed reduced AGO binding and functional mRNA de-repression of miR-122 targets during virus infection. This miR-122 "sponge" effect was relieved and redirected to miR-15 targets by swapping the miRNA tropism of the virus. Single-cell expression data from reporters containing miR-122 sites showed significant de-repression during HCV infection depending on expression level and site number. We describe a quantitative mathematical model of HCV-induced miR-122 sequestration and propose that such miR-122 inhibition by HCV RNA may result in global de-repression of host miR-122 targets, providing an environment fertile for the long-term oncogenic potential of HCV.

BACKGROUND: Efficacy trials have shown that antiviral therapy improves the outcomes of patients with chronic hepatitis B virus (HBV) infection. However, prospective data regarding the effect of antiviral therapy on the incidence of hepatocellular carcinoma (HCC), especially among patients without cirrhosis, are limited. The authors examined the impact of tenofovir disoproxil fumarate (TDF) on the incidence of HCC using a validated prediction model. METHODS: The incidence of HCC in patients treated with TDF was obtained in the pivotal TDF registration studies after 384 weeks of follow-up. The predicted risk of HCC in individual patients was calculated using the Risk Estimation for Hepatocellular Carcinoma in Chronic Hepatitis B (REACH-B) model, which estimates HCC incidence for up to 10 years based on age, sex, alanine aminotransferase level, hepatitis B e antigen status, and HBV-DNA. Standardized incidence ratios (SIRs) were calculated comparing the observed and predicted numbers of HCC cases in the study cohort. RESULTS: Among 634 patients with evaluable baseline biopsies, 152 had cirrhosis (Ishak fibrosis score of 5 or 6) and 482 did not. During the 384 weeks of study, 14 cases of HCC were reported, with 4 occurring within the first year. The incidence of HCC was 0.37% per year in the study as a whole (0.28% among patients without cirrhosis and 0.65% among patients with cirrhosis). Among patients without cirrhosis, the observed incidence of HCC was significantly lower than predicted (SIR, 0.40; 95% confidence interval, 0.199-0.795). The last HCC case in a patient with cirrhosis occurred around week 192 with an SIR of 0.51 (95% confidence interval, 0.231-1.144) reported at week 384. CONCLUSIONS: Based on the REACH-B risk calculator, long-term therapy with TDF was associated with a reduced incidence of HCC among patients without cirrhosis who met treatment criteria.

BACKGROUND & AIMS: Chronic hepatitis C treatment for prior non-responders to peginterferon (PegIFN)/ribavirin remains suboptimal. The MATTERHORN study evaluated regimens containing ritonavir-boosted danoprevir (danoprevir/r) in prior PegIFN alfa/ribavirin non-responders. METHODS: Prior partial responders (N=152) were randomized to 24 weeks of twice-daily danoprevir/r 100/100mg, mericitabine 1000 mg and ribavirin 1000/1200 mg (IFN-free); danoprevir/r plus PegIFN alfa-2a/ribavirin (triple); or danoprevir/r, mericitabine and PegIFN alfa-2a/ribavirin (Quad). Prior null responders (N=229) were randomized to 24 weeks of IFN-free therapy, or quad alone (Quad 24) or quad plus 24-weeks of PegIFN alfa-2a/ribavirin (Quad 48). The primary endpoint was sustained virological response (HCV RNA <25 IU/ml) 24 weeks after end-of-treatment (SVR24). Due to high relapse rates, genotype (G) 1a patients in IFN-free arms were offered additional PegIFN alfa-2a/ribavirin. RESULTS: Among prior partial responders, SVR24 rates were 46.2%, 51.0%, and 86.0%, in the IFN-free, Triple and Quad arms, respectively; among prior null responders, SVR24 rates were 45.5%, 80.5%, and 83.8% respectively. Relapse rates were lower and SVR24 rates higher in G1b-infected than G1a-infected patients. SVR24 rates in G1a and G1b patients randomized to Quad were 75.0% and 96.2%, respectively, in the partial Quad arm, and 68.1% and 100%, respectively, in the null Quad 24 arm. Treatment failure was associated with resistance to danoprevir, but not to mericitabine, and was more common in G1a infected patients. Treatment was well-tolerated. CONCLUSIONS: Danoprevir/r, mericitabine plus PegIFN alfa-2a/ribavirin was well-tolerated and produced high overall SVR24 rates in prior partial and null responders to PegIFN alfa/ribavirin. In contrast, IFN-free regimens were associated with unacceptably high relapse rates.