Beclabuvir in combination with asunaprevir and daclatasvir for hepatitis C virus genotype 1 infection: A systematic review and meta-analysis

Antitarget, Anti-SARS-CoV-2 Leads, Drugs, and the Drug Discovery-Genetics Alliance Perspective

The most advanced antiviral molecules addressing major SARS-CoV-2 targets (Main protease, Spike protein, and RNA polymerase), compared with proteins of other human pathogenic coronaviruses, may have a short-lasting clinical efficacy. Accumulating knowledge on the mechanisms underlying the target structural basis, its mutational progression, and the related biological significance to virus replication allows envisaging the development of better-targeted therapies in the context of COVID-19 epidemic and future coronavirus outbreaks. The identification of evolutionary patterns based solely on sequence information analysis for those targets can provide meaningful insights into the molecular basis of host-pathogen interactions and adaptation, leading to drug resistance phenomena. Herein, we will explore how the study of observed and predicted mutations may offer valuable suggestions for the application of the so-called "synthetic lethal" strategy to SARS-CoV-2 Main protease and Spike protein. The synergy between genetics evidence and drug discovery may prioritize the development of novel long-lasting antiviral agents.

The Fellowship of Privileged Scaffolds-One Structure to Inhibit Them All

Over the past few years, the application of privileged structure has emerged as a powerful approach to the discovery of new biologically active molecules. Privileged structures are molecular scaffolds with binding properties to the range of different biological targets. Moreover, privileged structures typically exhibit good drug-like properties, thus assuring more drug-like properties of modified compound. Our main objective is to discuss the privileged structures used for the development of antiviral agents.

Transition-Metal-Catalyzed Intermolecular C–H Carbonylation toward Amides

The amide linkage is one of the most important structural moieties in both chemistry and biology. Here, we briefly discuss recent advances in catalytic intermolecular C–H carbonylation reactions for the synthesis of amides, with particular attention to our intermolecular C–H amidation of arenes with carbon monoxide and organic azides to produce amides.

1 Introduction

2 Representative Methods for Amide Synthesis

3 C–H Aminocarbonylation with Carbon Monoxide and Amines

4 C–H Amidation to Amides with Carbon Monoxide and Azides

5 Summary and Outlook

Efficacy and safety of a fixed dose combination tablet of asunaprevir + beclabuvir + daclatasvir for the treatment of Hepatitis C

Introduction: Hepatitis C virus (HCV) is estimated to infect approximately 70 million people worldwide. If left untreated, chronic infection can progress to cirrhosis, liver failure or hepatocellular carcinoma. The advent of new direct-acting antivirals (DAA) has revolutionized patients' chances of treatment and viral elimination. Currently, several DAA options are available on the market.Areas covered: This review focuses on the pharmacokinetics, efficacy, tolerability and safety profile of DCV-TRIO, a twice-daily fixed-dose combination of daclatasvir, asunaprevir and beclabuvir approved in Japan for the treatment of genotype 1 HCV infection.Expert opinion: The DCV-TRIO combination achieved good response rates in genotype 1 patients (SVR12 ≥ 95% in naïve subtype 1b), independently from IL28B genotype, cirrhotic status and prior interferon exposure. On the other hand, unsatisfying response rates were reported in DAA-experienced patients and the risk of RAS selection should not be underestimated. Moreover, DCV-TRIO lacks differentiation from its earlier-launched DAA rivals, presents an inconvenient twice-daily dosing schedule and is not recommended in patients with advanced liver and kidney disease. All these drawbacks considerably limit its effective commercial potential. However, it can be a therapeutic option against HCV in tailored approaches according to the needs of different markets across the world.Abbreviations AE: adverse event; ALT: alanine aminotransferase; AST: aspartate aminotransferase; ASV: asunaprevir; AUC: area under the curve; BCRP: Breast Cancer Resistance Protein; BCV: boceprevir; BID: bis in die; CI: confidence intervals; CLcr: creatinine clearance; DAA: direct acting antivirals; DCV: daclatasvir; EC50: Half maximal effective concentration; GT: genotype; HCV: Hepatitis C virus; IFN: Interferon; NHL: non-Hodgkin lymphoma; OATP: Organic anion transporting polypeptides; OR: odds ratio; P-gp: P-glycoprotein; PK: pharmacokinetics; QD: quo die; RAS: resistance-associated substitutions; SVR: sustained virological response; USD: Unites States dollar.

Efficacy and safety of glecaprevir/pibrentasvir for chronic hepatitis C virus genotypes 1-6 infection: A systematic review and meta-analysis

This systematic review and meta-analysis investigated the efficacy and safety of glecaprevir and pibrentasvir (G/P) for chronic hepatitis C virus (HCV) infection. Pubmed, Embase, Cochrane Library and Scopus were searched to identify relevant studies through August 2018. Data from eligible studies were pooled and sustained virological response rates at 12 weeks' post-treatment (SVR12) were calculated. Thirteen studies with 3082 patients were included and the overall SVR12 rate was 97.8%. The SVR12 rates of subgroups were: G/P 300 mg/120 mg and 200 mg/120 mg: 97.9% and 98.3%; HCV genotype (GT)1, GT2, GT3 and GT4-6: 99.8%, 99.2%, 96.1% and 100%; G/P and G/P plus ribavirin (RBV): 97.9% and 98.2%; G/P (300 mg/120 mg) for 8 weeks, 12 weeks and 16 weeks: 98.8%, 98.5% and 95.6%; treatment-naïve and treatment-experienced patients: 96.7% and 98.3%; patients without and with compensated cirrhosis: 99.4% and 98.8%; patients without and with human immunodeficiency virus (HIV) co-infection: 97.8% and 99.4%; and patients without and with severe renal impairment (SRI): 97.8% and 99.4%. Virological failure and relapse and serious drug-related adverse events were rare. These results indicate that 8- or 12-week G/P treatment achieved high SVR12 rates in HCV GTs 1-6 patients without or with compensated cirrhosis, with good safety profiles, irrespective of dose, RBV use, treatment-experience, HIV co-infection and renal impairment. Due to the limited number of evaluated patients with GT3 infection, further studies are needed to define optimal treatment duration for GT3 cirrhosis patients and patients with prior treatment experience of direct-acting antivirals.

Oxidative degradation pathways of beclabuvir hydrochloride mediated by hydrogen peroxide and UV/Vis light

Beclabuvir hydrochloride (BCV) is a marketed product for the treatment of hepatitis C viral infection. It contains functional groups such as indole, tertiary amine and amides. Forced degradation studies of BCV revealed different degradation profiles under photo and hydrogen peroxide oxidative conditions. Under the photo-oxidative degradation conditions, the tertiary amine on the piperazine ring was oxidized to form the degradants as the hydroxyl and des-methyl analogs of beclabuvir. However, under the oxidative condition using hydrogen peroxide, the indole ring was oxidized to form a typical kynuric degradant and two unexpected cyclohexyl rearranged diastereomeric degradants. The plausible mechanisms for the photo and hydrogen peroxide mediated oxidative degradation of beclabuvir hydrochloride are proposed.

The Discovery and Early Clinical Evaluation of the HCV NS3/4A Protease Inhibitor Asunaprevir (BMS-650032)

The discovery of asunaprevir (1) began with the concept of engaging the small and well-defined S₁’ pocket of the hepatitis C virus (HCV) NS3/4A protease that was explored in the context of tripeptide carboxylic acid-based inhibitors. A cyclopropyl-acyl sulfonamide moiety was found to be the optimal element at the P₁-P₁’ interface enhancing the potency of carboxylic acid-based prototypes by 10- to >100-fold, dependent upon the specific background. Optimization for oral bioavailability identified a 1-substituted isoquinoline-based P₂* element that conferred a significant exposure advantage in rats compared to the matched 4-substituted quinoline isomer. BMS-605339 (30) was the first cyclopropyl-acyl sulfonamide derivative advanced into clinical trials that demonstrated dose-related reductions in plasma viral RNA in HCV-infected patients. However, 30 was associated with cardiac events observed in a normal healthy volunteer (NHV) and an HCV-infected patient that led to the suspension of the development program. Using a Langendorff rabbit heart model, a limited structure-cardiac liability relationship was quickly established that led to the discovery of 1. This compound, which differs from 30 only by changes in the substitution pattern of the P₂* isoquinoline heterocycle and the addition of a single chlorine atom to the molecular formula, gave a dose-dependent reduction in plasma viral RNA following oral administration to HCV-infected patients without the burden of the cardiac events that had been observed with 30. A small clinical trial of the combination of 1 with the HCV NS5A inhibitor daclatasvir (2) established for the first time that a chronic genotype 1 (GT-1) HCV infection could be cured by therapy with two direct-acting antiviral agents in the absence of exogenous immune-stimulating agents. Development of the combination of 1 and 2 was initially focused on Japan where the patient population is predominantly infected with GT-1b virus, culminating in marketing approval which was granted on July 4, 2014. In order to broaden therapy to include GT-1a infections, a fixed dose triple combination of 1, 2, and the allosteric NS5B inhibitor beclabuvir (3) was developed, approved by the Japanese health authorities for the treatment of HCV GT-1 infection on December 20, 2016 and marketed as Ximency^®.

Pharmacokinetic and pharmacodynamic evaluation of daclatasvir, asunaprevir plus beclabuvir as a fixed-dose co-formulation for the treatment of hepatitis C

INTRODUCTION

Many reports have evaluated the clinical efficacy and safety of the fixed-dose all-oral combination of daclatasvir, asunaprevir, and beclabuvir (DCV-TRIO), which was approved in Japan in December 2016 for the treatment of hepatitis C genotype (GT)-1 infection. Areas covered: This article reviews the pharmacodynamic and pharmacokinetic properties of the DCV-TRIO combination. The topics covered include data regarding the drug's absorption, distribution, metabolism, excretion, and antiviral activity strategies. Its therapeutic efficacy and safety in GT-1 infection from phase 2/3 clinical trials are also discussed. Expert opinion: The ideal regimen for the treatment of Hepatitis C virus infection should be potent, pangenotypic, Ribavirin-free, safe, co-formulated, and affordable. Considering these characteristics, DCV-TRIO is neither pangenotypic nor potent enough against GT-1a, regardless of the presence or absence of cirrhosis. Other potential limitations of this regimen are its dosification (twice-daily), and the fact that since it includes a protease inhibitor, it is contraindicated in decompensated cirrhosis. For these reasons, it has only been approved in Japan, where more than 70% of the patients are infected with GT-1b. However, this co-formulation might still have a place in the treatment of non-cirrhotic patients infected with GT-1b provided that massive access to treatment is facilitated.