Viral hepatitis C treatment shortening - what is the limit?

Decade of optimizing therapy with direct-acting antiviral drugs and the changing profile of patients with chronic hepatitis C

Chronic infection with the hepatitis C virus (HCV) remains a major health problem affecting approximately 58 million people worldwide. In the era of interferon (IFN)-based regimens, patients particularly infected with genotypes 1 and 4 achieved a low response rate. The implementation of direct-acting antivirals changed the landscape of HCV treatment. The increase in effectiveness provided us with the hope of eliminating HCV as a significant public threat by 2030. In the following years, there was an observed improvement in the treatment of HCV with genotype-specific regimens and highly effective pangenotypic options that are the most recent stage of the revolution. The optimization of therapy was accompanied by changes in the patient profile from the beginning of the IFN-free era over time. Patients treated with antiviral therapies were younger in successive periods, less burdened with comorbidities and comedications, more frequently treatment-naïve and had less advanced liver disease. Before the IFN-free era, specific subpopulations such as patients with HCV/HIV coinfection, those with a history of previous treatment, patients with renal impairment or with cirrhosis had lower chances for a virologic response. Currently, these populations should no longer be considered difficult to treat. Despite the high effectiveness of HCV therapy, there is a small percentage of patients with treatment failure. However, they can be effectively retreated with pangenotypic rescue regimens.

Glecaprevir/pibrentasvir for 8 weeks in patients with compensated cirrhosis: Safety and effectiveness data from the German Hepatitis C-Registry

Glecaprevir/pibrentasvir, a pangenotypic, direct-acting antiviral combination approved for chronic hepatitis C virus treatment, has limited real-world evidence supporting 8-week therapy in compensated cirrhosis. We investigated effectiveness and safety of 187 hepatitis C virus-infected, treatment-naïve, patients with compensated cirrhosis receiving 8-week glecaprevir/pibrentasvir therapy in the German Hepatitis C-Registry between 2 August 2017 and 1 January 2020. Sustained virologic response was 98.4% (127/129) in the per-protocol analysis (excluding patients lost to follow-up or who discontinued treatment due to compliance) and was 85.8% (127/148) in patients with data available in an intention-to-treat analysis. Nineteen patients were lost to follow-up; nine genotype 3 patients, nine nongenotype 3 patients and one mixed genotype patient. One patient relapsed, and one died, unrelated to treatment. Adverse events (>5%) were fatigue and headache. Two serious adverse events occurred; no adverse events resulted in drug discontinuation. An 8-week glecaprevir/pibrentasvir therapy was effective and well-tolerated in this real-world analysis.

Management of hepatitis B and hepatitis C coinfection: an expert review

INTRODUCTION

Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections share common routes of transmission. HBV/HCV coinfection can lead to interactions affecting mechanisms of infection and therapy.

AREAS COVERED

In the review, we present epidemiology of HBV/HCV coinfection and current therapeutic options for both viruses. The possibility of drug-drug interactions during the treatment of coinfected patients is discussed. However, the major part of the review is dedicated to interactions between viruses and risk of HBV reactivation during HCV treatment with direct-acting antivirals (DAA). Finally, we analyze available international and national guidelines for the management of HBV reactivations related to DAA administration.

EXPERT OPINION

The most important international societies' guidelines include comments on HBV/HCV coinfection, but due to their inconsistency we present a proposal of management for HBV/HCV coinfected patients focusing mostly on HBV reactivation in patients treated for HCV. We provide some advice that should be considered in future guidelines for the management of HBV/HCV coinfection.

An Overview on ERAP Roles in Infectious Diseases

Endoplasmic reticulum (ER) aminopeptidases ERAP1 and ERAP2 (ERAPs) are crucial enzymes shaping the major histocompatibility complex I (MHC I) immunopeptidome. In the ER, these enzymes cooperate in trimming the N-terminal residues from precursors peptides, so as to generate optimal-length antigens to fit into the MHC class I groove. Alteration or loss of ERAPs function significantly modify the repertoire of antigens presented by MHC I molecules, severely affecting the activation of both NK and CD8+ T cells. It is, therefore, conceivable that variations affecting the presentation of pathogen-derived antigens might result in an inadequate immune response and onset of disease. After the first evidence showing that ERAP1-deficient mice are not able to control Toxoplasma gondii infection, a number of studies have demonstrated that ERAPs are control factors for several infectious organisms. In this review we describe how susceptibility, development, and progression of some infectious diseases may be affected by different ERAPs variants, whose mechanism of action could be exploited for the setting of specific therapeutic approaches.