Faculty Bibliography

BACKGROUND & AIMS: We compared outcomes by cirrhosis status across studies of the all-oral combination of daclatasvir (DCV) plus asunaprevir (ASV). METHODS: Outcomes from global and Japanese phase 2 and 3 clinical studies of DCV+ASV in patients with genotype (GT) 1b infection were assessed by cirrhosis status. Sustained virological response (SVR) was assessed in individual phase 3 studies; a pooled analysis was carried out for safety outcomes. RESULTS: In the Japanese phase 3 study, SVR12 was achieved by 91% of patients with cirrhosis (n = 22) and 84% of patients without cirrhosis (n = 200); in the global phase 3 study, SVR12 was achieved by 84% of patients with cirrhosis (n = 206) and by 85% of patients without cirrhosis (n = 437). The frequency of serious adverse events, adverse events leading to treatment discontinuation and treatment-emergent grade 3/4 laboratory abnormalities was low (<10%) and similar among patients with (n = 229) or without (n = 689) compensated cirrhosis receiving DCV+ASV. Grade 3/4 reductions in platelets and neutrophils were more common among patients with cirrhosis (1.3 and 2.2%, respectively) compared with those without cirrhosis (both 0.6%). Grade 3/4 liver function test abnormalities were less common among patients with cirrhosis (1.8%) compared with those without cirrhosis (3.5-4.7%). Alanine aminotransferase elevations were not associated with hepatic decompensation. CONCLUSIONS: The safety and efficacy of DCV+ASV were similar in patients with or without compensated cirrhosis. This all-oral, interferon- and ribavirin-free combination is an effective and well-tolerated treatment option for patients with HCV GT1b infection and cirrhosis. Trial registrations numbers: Clinicaltrials.gov identifiers: NCT01012895; NCT01051414; NCT01581203; NCT01497834.

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.

BACKGROUND: GS-9620 is a potent oral agonist of toll-like receptor 7, a key modulator of the innate immune response. In healthy volunteers, low doses of GS-9620 (2, 4 and 6 mg) induced significant expression of peripheral interferon-stimulated-gene (ISG) mRNA in the absence of detectable serum interferon-alpha and systemic adverse events (AEs). We evaluated the safety, pharmacokinetics and pharmacodynamics of GS-9620 in treatment-naive patients chronically infected with HCV genotype 1. METHODS: In this double-blind, placebo-controlled study, 51 patients were randomized 5:1 (active:placebo) to receive either a single dose or two once-weekly doses of GS-9620 at four dose levels (0.3, 1, 2 and 4 mg) or placebo. Pharmacodynamic assessments included peripheral ISG15 mRNA expression, serum interferon-alpha and interferon-gamma-inducible protein (IP)-10 levels and HCV RNA quantification. RESULTS: GS-9620 was well-tolerated at all doses. Most AEs were mild or moderate in severity. GS-9620 exhibited dose-linear pharmacokinetics with a median half-life in plasma of 18 h. Transient, dose-dependent ISG15 induction was observed at 1, 2 and 4 mg, with peak mean fold change within 48 h followed by a decline to baseline levels within 7 days of dosing. Serum interferon-alpha induction post-baseline was detected in 16.7% (8/48) of patients. No clinically significant reductions in HCV RNA were observed. CONCLUSIONS: GS-9620 was safe, well-tolerated and biologically active in patients with HCV infection. Induction of ISG15 occurred in the absence of detectable serum interferon-alpha or systemic AEs in most patients, supporting a pre-systemic mechanism of action. ClinicalTrials.gov identifier: NCT01591668.

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: We evaluated the antiviral response of Asian or Pacific Islander (API) patients with chronic hepatitis B (CHB) who had baseline high viral load (HVL), defined as pre-treatment hepatitis B virus (HBV) DNA >/=9 log10 copies/ml, following up to 288 weeks of tenofovir disoproxil fumarate (TDF) treatment. METHODS: A total of 205 HBeAg-negative and HBeAg-positive self-described API patients received 48 weeks of TDF 300 mg (HVL n = 18) or adefovir dipivoxil 10 mg (HVL n = 15) in a blinded fashion, followed by open-label TDF for an additional 240 weeks. The proportions of HVL vs. non-HVL patients with HBV DNA <400 copies/ml were compared. Mean declines in HBV DNA were evaluated in API vs. non-API patients. RESULTS: Throughout the first 72 weeks of treatment, a smaller proportion of HVL API patients reached HBV DNA <400 copies/ml than non-HVL API patients. However, after this timepoint similar proportions of HVL and non-HVL API patients achieved HBV DNA <400 copies/ml (100% vs. 97%, respectively), which was maintained through week 288, where 92% of HVL patients and 99% of non-HVL API patients on treatment had HBV DNA <400 copies/ml. During the 288 weeks of treatment, API patients had similar mean HBV DNA declines as non-API patients, regardless of whether patients were HVL or non-HVL. No API HVL patient had persistent viremia at week 288. No resistance was detected among HVL or non-HVL patients. CONCLUSIONS: API patients with HVL CHB achieve HBV DNA <400 copies/ml with long-term TDF treatment; however, achieving viral suppression may take longer for HVL patients relative to non-HVL API patients.

OBJECTIVE: The natural course of chronic hepatitis C varies widely. To improve the profiling of patients at risk of developing advanced liver disease, we assessed the relative contribution of factors for liver fibrosis progression in hepatitis C. DESIGN: We analysed 1461 patients with chronic hepatitis C with an estimated date of infection and at least one liver biopsy. Risk factors for accelerated fibrosis progression rate (FPR), defined as >/= 0.13 Metavir fibrosis units per year, were identified by logistic regression. Examined factors included age at infection, sex, route of infection, HCV genotype, body mass index (BMI), significant alcohol drinking (>/= 20 g/day for >/= 5 years), HIV coinfection and diabetes. In a subgroup of 575 patients, we assessed the impact of single nucleotide polymorphisms previously associated with fibrosis progression in genome-wide association studies. Results were expressed as attributable fraction (AF) of risk for accelerated FPR. RESULTS: Age at infection (AF 28.7%), sex (AF 8.2%), route of infection (AF 16.5%) and HCV genotype (AF 7.9%) contributed to accelerated FPR in the Swiss Hepatitis C Cohort Study, whereas significant alcohol drinking, anti-HIV, diabetes and BMI did not. In genotyped patients, variants at rs9380516 (TULP1), rs738409 (PNPLA3), rs4374383 (MERTK) (AF 19.2%) and rs910049 (major histocompatibility complex region) significantly added to the risk of accelerated FPR. Results were replicated in three additional independent cohorts, and a meta-analysis confirmed the role of age at infection, sex, route of infection, HCV genotype, rs738409, rs4374383 and rs910049 in accelerating FPR. CONCLUSIONS: Most factors accelerating liver fibrosis progression in chronic hepatitis C are unmodifiable.

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.