scholarly journals Preclinical Characterization of BI 201335, a C-Terminal Carboxylic Acid Inhibitor of the Hepatitis C Virus NS3-NS4A Protease

2010 ◽  
Vol 54 (11) ◽  
pp. 4611-4618 ◽  
Author(s):  
Peter W. White ◽  
Montse Llinàs-Brunet ◽  
Ma'an Amad ◽  
Richard C. Bethell ◽  
Gordon Bolger ◽  
...  

ABSTRACT BI 201335 is a hepatitis C virus (HCV) NS3-NS4A (NS3 coexpressed with NS4A) protease inhibitor that has been shown to have potent clinical antiviral activity. It is a highly optimized noncovalent competitive inhibitor of full-length NS3-NS4A proteases of HCV genotypes 1a and 1b with Ki values of 2.6 and 2.0 nM, respectively. Ki values of 2 to 230 nM were measured against the NS3-NS4A proteases of HCV genotypes 2 to 6, whereas it was a very weak inhibitor of cathepsin B and showed no measurable inhibition of human leukocyte elastase. BI 201335 was also shown to be a potent inhibitor of HCV RNA replication in vitro with 50% effective concentrations (EC50s) of 6.5 and 3.1 nM obtained in genotype 1a and 1b replicon assays. Combinations of BI 201335 with either interferon or ribavirin had additive effects in replicon assays. BI 201335 had good permeability in Caco-2 cell assays and high metabolic stability after incubation with human, rat, monkey, and dog liver microsomes. Its good absorption, distribution, metabolism, and excretion (ADME) profile in vitro, as well as in rat, monkey, and dog, predicted good pharmacokinetics (PK) in humans. Furthermore, drug levels were significantly higher in rat liver than in plasma, suggesting that distribution to the target organ may be especially favorable. BI 201335 is a highly potent and selective NS3-NS4A protease inhibitor with good in vitro and animal ADME properties, consistent with its good human PK profile, and shows great promise as a treatment for HCV infection.

2004 ◽  
Vol 48 (12) ◽  
pp. 4784-4792 ◽  
Author(s):  
Kai Lin ◽  
Ann D. Kwong ◽  
Chao Lin

ABSTRACT The present standard of care for hepatitis C virus (HCV) infection is pegylated alpha interferon (IFN-α) in combination with ribavirin. However, specific antivirals such as HCV NS3-NS4A protease inhibitors are now in clinical development, and these agents can potentially be used in combination with the present treatments. Therefore, it is important to investigate the potential benefits or adverse effects of these new combinations by using available in vitro HCV culture systems first. In the present study we demonstrate that the combination of a specific HCV NS3-NS4A protease inhibitor and IFN-α synergistically inhibits HCV RNA replication in replicon cells, with little or no increase in cytotoxicity. Furthermore, the benefit of the combination was sustained over time, such that a greater than 3-log reduction in HCV RNA levels was achieved following 9 days of treatment. The viral RNA appeared to be cleared from the replicon cells after 14 days of treatment, and no viral RNA rebound was observed upon withdrawal of the inhibitors. In each case, the antiviral effects obtained with higher concentrations of either the protease inhibitor alone or IFN-α alone can be achieved by a combination of both agents at lower concentrations, which may potentially reduce the risk of possible adverse effects associated with high doses of either agent.


2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Teresa I. Ng ◽  
Rakesh Tripathi ◽  
Thomas Reisch ◽  
Liangjun Lu ◽  
Timothy Middleton ◽  
...  

ABSTRACTGlecaprevir (formerly ABT-493) is a novel hepatitis C virus (HCV) NS3/4A protease inhibitor (PI) with pangenotypic activity. It inhibited the enzymatic activity of purified NS3/4A proteases from HCV genotypes 1 to 6in vitro(half-maximal [50%] inhibitory concentration = 3.5 to 11.3 nM) and the replication of stable HCV subgenomic replicons containing proteases from genotypes 1 to 6 (50% effective concentration [EC50] = 0.21 to 4.6 nM). Glecaprevir had a median EC50of 0.30 nM (range, 0.05 to 3.8 nM) for HCV replicons containing proteases from 40 samples from patients infected with HCV genotypes 1 to 5. Importantly, glecaprevir was active against the protease from genotype 3, the most-difficult-to-treat HCV genotype, in both enzymatic and replicon assays demonstrating comparable activity against the other HCV genotypes. In drug-resistant colony selection studies, glecaprevir generally selected substitutions at NS3 amino acid position A156 in replicons containing proteases from genotypes 1a, 1b, 2a, 2b, 3a, and 4a and substitutions at position D/Q168 in replicons containing proteases from genotypes 3a, 5a, and 6a. Although the substitutions A156T and A156V in NS3 of genotype 1 reduced susceptibility to glecaprevir, replicons with these substitutions demonstrated a low replication efficiencyin vitro. Glecaprevir is active against HCV with most of the common NS3 amino acid substitutions that are associated with reduced susceptibility to other currently approved HCV PIs, including those at positions 155 and 168. Combination of glecaprevir with HCV inhibitors with other mechanisms of action resulted in additive or synergistic antiviral activity. In summary, glecaprevir is a next-generation HCV PI with potent pangenotypic activity and a high barrier to the development of resistance.


2012 ◽  
Vol 57 (1) ◽  
pp. 436-444 ◽  
Author(s):  
Naoki Ogura ◽  
Yukiyo Toyonaga ◽  
Izuru Ando ◽  
Kunihiro Hirahara ◽  
Tsutomu Shibata ◽  
...  

ABSTRACTJTK-853, a palm site-binding NS5B nonnucleoside polymerase inhibitor, shows antiviral activityin vitroand in hepatitis C virus (HCV)-infected patients. Here, we report the results of genotypic and phenotypic analyses of resistant variants in 24 HCV genotype 1-infected patients who received JTK-853 (800, 1,200, or 1,600 mg twice daily or 1,200 mg three times daily) in a 3-day monotherapy. Viral resistance in NS5B was investigated using HCV RNA isolated from serum specimens from the patients. At the end of treatment (EOT) with JTK-853, the amino acid substitutions M414T (methionine [M] in position 414 at baseline was replaced with threonine [T] at EOT), C445R (cysteine [C] in position 445 at baseline was replaced with arginine [R] at EOT), Y448C/H (tyrosine [Y] in position 448 at baseline was replaced with cysteine [C] or histidine [H] at EOT), and L466F (leucine [L] in position 466 at baseline was replaced with phenylalanine [F] at EOT), which are known to be typical resistant variants of nonnucleoside polymerase inhibitors, were observed in a clonal sequencing analysis. These substitutions were also selected by a treatment with JTK-853in vitro, and the 50% effective concentration of JTK-853 in the M414T-, C445F-, Y448H-, and L466V-harboring replicons attenuated the susceptibility by 44-, 5-, 6-, and 21-fold, respectively, compared with that in the wild-type replicon (Con1). These findings suggest that amino acid substitutions of M414T, C445R, Y448C/H, and L466F are thought to be viral resistance mutations in HCV-infected patients receiving JTK-853 in a 3-day monotherapy.


2003 ◽  
Vol 49 (8) ◽  
pp. 503-507 ◽  
Author(s):  
Regina Moreira ◽  
João Renato Rebello Pinho ◽  
Jorge Fares ◽  
Isabel Takano Oba ◽  
Maria Regina Cardoso ◽  
...  

The aims of this study were to (i) evaluate the prevalence and the incidence of hepatitis C virus (HCV) infection in hemodialysis patients in two different centers in São Paulo (Brazil), (ii) determine the time required to detect HCV infection among these patients by serology or PCR, (iii) establish the importance of alanine aminotransferase determination as a marker of HCV infection, and (iv) identify the HCV genotypes in this population. Serum samples were collected monthly for 1 year from 281 patients admitted to hospital for hemodialysis. Out of 281 patients, 41 patients (14.6%) were HCV positive; six patients seroconverted during this study (incidence = 3.1/1000 person-month). In 1.8% (5/281) of cases, RNA was detected before the appearance of antibodies (up to 5 months), and in 1.1% (3/281) of cases, RNA was the unique marker of HCV infection. The genotypes found were 1a, 1b, 3a, and 4a. The presence of genotype 4a is noteworthy, since it is a rare genotype in Brazil. These data pointed out the high prevalence and incidence of HCV infection at hemodialysis centers in Brazil and showed that routine PCR is fundamental for improving the detection of HCV carriers among patients undergoing hemodialysis.Key words: HCV genotypes, hemodialysis, hepatitis C, PCR, prevalence, incidence.


2019 ◽  
Vol 49 ◽  
Author(s):  
Irma Salimović- Bešić ◽  
Adna Kahriman ◽  
Suzana Arapčić ◽  
Amela Dedeić- Ljubović

Background: Hepatitis C virus (HCV) genotypes and subtypes exhibit significant geographic variations.Aim: To analyse the distribution of genotypes/subtypes of HCV in a group of patients with chronic hepatitis C from Canton Sarajevo during 2012-2018.Material and methods:The study enrolled 247 human plasma samples of HCV-RNA positive patients with available results of HCV genotyping test.Results: During 2012-2018, the domination of subtypes 1a (34.01%), 1b (28.34%) and genotype 3 (23.89%) was registered. In 2012 and 2013, HCV subtype 1a was the most common (27/63; 42.86% and 17/40; 42.50%, respectively). In 2014, the leading HCV genotype/subtype were 3 and 1b (17/57; 29.82%). In 2015, the dominance of HCV genotype 3 (14/39; 35.90%) continued, while in 2016, the same number of HCV subtypes 1a and 1b (11/30; 36.67%) was recorded. Although in a small number of tested, during 2017, HCV subtype 1b was the most prevalent (7/14; 50.00%), and in 2018, it was replaced by a HCV subtype 1a (3/4; 75.00%). Distribution of HCV genotypes/subtypes by age group of patients varied significantly (p=0.000). The largest number of patients (71/247; 28.74%) belonged to the age category 30-39 years and HCV genotypes/subtypes 1, 3, 4, 1a and 1b were identified. Except in 2017, male gender significantly dominated (p=0.000). In males, HCV subtype 1a (68/170; 40.00%) was the most common, while in women it was HCV subtype 1b (44/77; 57.14%).Conclusion: This six-year retrospective study showed the time variations of the circulating HCV genotypes/subtypes among patients with chronic hepatitis C in Canton Sarajevo. Genotyping of the HCV has an important implications for diagnosis and treatment of the patients.


2018 ◽  
Vol 19 (9) ◽  
pp. 2771 ◽  
Author(s):  
Yoo Cho ◽  
Hwan Lee ◽  
Hyojeung Kang ◽  
Hyosun Cho

HCV genotype 2a strain JFH-1 replicates and produces viral particles efficiently in human hepatocellular carcinoma (huh) 7.5 cells, which provide a stable in vitro cell infection system for the hepatitis C virus (HCVcc system). Natural killer (NK) cells are large lymphoid cells that recognize and kill virus-infected cells. In this study, we investigated the interaction between NK cells and the HCVcc system. IL-10 is a typical immune regulatory cytokine that is produced mostly by NK cells and macrophages. IL-21 is one of the main cytokines that stimulate the activation of NK cells. First, we used anti-IL-10 to neutralize IL-10 in a coculture of NK cells and HCVcc. Anti-IL-10 treatment increased the maturation of NK cells by enhancing the frequency of the CD56+dim population in NK-92 cells. However, with anti-IL-10 treatment of NK cells in coculture with J6/JFH-1-huh 7.5 cells, there was a significant decrease in the expression of STAT1 and STAT5 proteins in NK-92 cells and an increase in the HCV Core and NS3 proteins. In addition, rIL-21 treatment increased the frequency of the CD56+dim population in NK-92 cells, Also, there was a dramatic increase in the expression of STAT1 and STAT5 proteins in rIL-21 pre-stimulated NK cells and a decrease in the expression of HCV Core protein in coculture with J6/JFH-1-huh 7.5 cells. In summary, we found that the functional activation of NK cells can be modulated by anti-IL-10 or rIL-21, which controls the expression of HCV proteins as well as HCV RNA replication.


2014 ◽  
Vol 58 (9) ◽  
pp. 5155-5163 ◽  
Author(s):  
Chunfu Wang ◽  
Lingling Jia ◽  
Donald R. O'Boyle ◽  
Jin-Hua Sun ◽  
Karen Rigat ◽  
...  

ABSTRACTA comparison of the daclatasvir (DCV [BMS-790052]) resistance barrier on authentic or hybrid replicons containing NS5A from hepatitis C virus (HCV) genotypes 1 to 6 (GT-1 to -6) was completed using a replicon elimination assay. The data indicated that genotype 1b (GT-1b) has the highest relative resistance barrier and genotype 2a (GT-2a M31) has the lowest. The rank order of resistance barriers to DCV was 1b > 4a ≥ 5a > 6a ≅ 1a > 2a JFH > 3a > 2a M31. Importantly, DCV in combination with a protease inhibitor (PI) eliminated GT-2a M31 replicon RNA at a clinically relevant concentration. Previously, we reported the antiviral activity and resistance profiles of DCV on HCV genotypes 1 to 4 evaluated in the replicon system. Here, we report the antiviral activity and resistance profiles of DCV against hybrid replicons with NS5A sequences derived from HCV GT-5a and GT-6a clinical isolates. DCV was effective against both GT-5a and -6a hybrid replicon cell lines (50% effective concentrations [EC50s] ranging from 3 to 7 pM for GT-5a, and 74 pM for GT-6a). Resistance selection identified amino acid substitutions in the N-terminal domain of NS5A. For GT-5a, L31F and L31V, alone or in combination with K56R, were the major resistance variants (EC50s ranging from 2 to 40 nM). In GT-6a, Q24H, L31M, P32L/S, and T58A/S were identified as resistance variants (EC50s ranging from 2 to 250 nM). Thein vitrodata suggest that DCV has the potential to be an effective agent for HCV genotypes 1 to 6 when used in combination therapy.


2013 ◽  
Vol 58 (2) ◽  
pp. 647-653 ◽  
Author(s):  
Huiling Yang ◽  
Margaret Robinson ◽  
Amoreena C. Corsa ◽  
Betty Peng ◽  
Guofeng Cheng ◽  
...  

ABSTRACTGS-9451 is a selective hepatitis C virus (HCV) NS3 protease inhibitor in development for the treatment of genotype 1 (GT1) HCV infection. Key preclinical properties of GS-9451, includingin vitroantiviral activity, selectivity, cross-resistance, and combination activity, as well as pharmacokinetic properties, were determined. In multiple GT1a and GT1b replicon cell lines, GS-9451 had mean 50% effective concentrations (EC50s) of 13 and 5.4 nM, respectively, with minimal cytotoxicity; similar potency was observed in chimeric replicons encoding the NS3 protease gene of GT1 clinical isolates. GS-9451 was less active in GT2a replicon cells (EC50= 316 nM). Additive to synergisticin vitroantiviral activity was observed when GS-9451 was combined with other agents, including alpha interferon, ribavirin, and the polymerase inhibitors GS-6620 and tegobuvir (GS-9190), as well as the NS5A inhibitor ledipasvir (GS-5885). GS-9451 retained wild-type activity against multiple classes of NS5B and NS5A inhibitor resistance mutations. GS-9451 was stable in hepatic microsomes and hepatocytes from human and three other tested species. Systemic clearance was low in dogs and monkeys but high in rats. GS-9451 showed good oral bioavailability in all three species tested. In rats, GS-9451 levels were ∼40-fold higher in liver than plasma after intravenous dosing, and elimination of GS-9451 was primarily through biliary excretion. Together, these results are consistent with the antiviral activity observed in a recent phase 1b study. The results ofin vitrocross-resistance and combination antiviral assays support the ongoing development of GS-9451 in combination with other agents for the treatment of chronic HCV infection.


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