Fabien Zoulim

EASL Clinical Practice Guidelines: Management of chronic hepatitis B

Our understanding of the natural history of hepatitis B virus (HBV) infection and the potential for therapy of the resultant disease has improved. Several new and effective antiviral agents have been evaluated and licensed since the EASL International Consensus Conference on hepatitis B held in 2002 [1]. The objective of these EASL Clinical Practice Guidelines (CPGs) is to update recommendations for the optimal management of chronic hepatitis B (CHB). The CPGs do not focus on prevention and vaccination. Several difficulties remain in formulating treatments for CHB; thus areas of uncertainty exist. At the present time clinicians, patients and public health authorities must continue to make choices on the basis of evidence that is not fully matured.

A new genotype of hepatitis B virus: complete genome and phylogenetic relatedness

The hepatitis B virus (HBV) genotype was determined in a total of 121 plasma samples collected in France and the US from patients chronically infected with HBV. HBV genotype A was predominant in this collection, appearing in 66 samples (54%), while genotypes B, C, D, E and F occurred in 4 (3%), 14 (12%), 23 (19%), 1 (1%) and 0 (0%) of samples, respectively. However, the genotype of a total of 13 (11%) samples (2 from France, 11 from the US) could not be determined with the methodology used. Sequence analysis, and subsequent phylogenetic analysis of the complete genome and the individual open reading frames, showed that the virus isolate from these samples was 3248 bp long and, phylogenetically, did not cluster with any of the known genotypes. This strain was provisionally called HBV genotype G. Virus isolates that were obtained from geographically separated regions like France and the US were closely related to each other. All virus strains analysed contained some characteristic differences when compared to genotype A: a translational stop codon at aa 2 and 28 of the preCore region; a 36 nt (12 aa) insert in the amino-terminal part of the Core antigen (HBcAg); a 2 aa deletion in the carboxy-terminal part of HBcAg; and a 1 aa deletion in the preS1 open reading frame. The deduced amino acid sequence of HBsAg suggests that this newly discovered genotype G strain belongs to serological group adw2.

STATEMENTS FROM THE TAORMINA EXPERT MEETING ON OCCULT HEPATITIS B VIRUS INFECTION

Giovanni Raimondo*, Jean-Pierre Allain, Maurizia R. Brunetto, Marie-Annick Buendia, Ding-Shinn Chen, Massimo Colombo, Antonio Craxi, Francesco Donato, Carlo Ferrari, Giovanni B. Gaeta, Wolfram H. Gerlich, Massimo Levrero, Stephen Locarnini, Thomas Michalak, Mario U. Mondelli, Jean-Michel Pawlotsky, Teresa Pollicino, Daniele Prati, Massimo Puoti, Didier Samuel, Daniel Shouval, Antonina Smedile, Giovanni Squadrito, Christian Trepo, Erica Villa, Hans Will, Alessandro R. Zanetti, Fabien Zoulim

Hepatitis B Virus Resistance to Nucleos(t)ide Analogues

Patients with chronic hepatitis B (CHB) can be successfully treated using nucleos(t)ide analogs (NA), but drug-resistant hepatitis B virus (HBV) mutants frequently arise, leading to treatment failure and progression to liver disease. There has been much research into the mechanisms of resistance to NA and selection of these mutants. Five NA have been approved by the US Food and Drug Administration for treatment of CHB; it is unlikely that any more NA will be developed in the near future, so it is important to better understand mechanisms of cross-resistance (when a mutation that mediates resistance to one NA also confers resistance to another) and design more effective therapeutic strategies for these 5 agents. The genes that encode the polymerase and envelope proteins of HBV overlap, so resistance mutations in polymerase usually affect the hepatitis B surface antigen; these alterations affect infectivity, vaccine efficacy, pathogenesis of liver disease, and transmission throughout the population. Associations between HBV genotype and resistance phenotype have allowed cross-resistance profiles to be determined for many commonly detected mutants, so genotyping assays can be used to adapt therapy. Patients that experience virologic breakthrough or partial response to their primary therapy can often be successfully treated with a second NA, if this drug is given at early stages of these events. However, best strategies for preventing NA resistance include first-line use of the most potent antivirals with a high barrier to resistance. It is important to continue basic research into HBV replication and pathogenic mechanisms to identify new therapeutic targets, develop novel antiviral agents, design combination therapies that prevent drug resistance, and decrease the incidence of complications of CHB.

Triple therapy in treatment-experienced patients with HCV-cirrhosis in a multicentre cohort of the French Early Access Programme (ANRS CO20-CUPIC) – NCT01514890

BACKGROUND & AIMS In phase III trials, the safety profile of triple therapy (pegylated interferon/ribavirin with boceprevir or telaprevir) seems to be similar in HCV treatment-experienced cirrhotic and non-cirrhotic patients, but few cirrhotics were included. We report the week 16 safety and efficacy analysis in a cohort of compensated cirrhotics treated in the French Early Access Programme. METHODS 674 genotype 1 patients, prospectively included, received 48 weeks of triple therapy. The analysis is restricted to 497 patients reaching week 16. RESULTS A high incidence of serious adverse events (40.0%), and of death and severe complications (severe infection or hepatic decompensation) (6.4%), and a difficult management of anaemia (erythropoietin and transfusion use in 50.7% and 12.1%) were observed. Independent predictors of anaemia < 8 g/dl or blood transfusion were: female gender (OR 2.19, 95% CI 1.11-4.33, p=0.024), no lead-in phase (OR 2.25, 95% CI 1.15-4.39, p=0.018), age ≥ 65 years (OR 3.04, 95% CI 1.54-6.02, p=0.0014), haemoglobin level (≤ 12 g/dl for females, ≤ 13 g/dl for males) (OR 5.30, 95% CI 2.49-11.5, p=0.0001). Death or severe complications were related to platelets count ≤ 100,000/mm(3) (OR 3.11, 95% CI 1.30-7.41, p=0.0105) and albumin <35 g/dl (OR 6.33, 95% CI 2.66-15.07, p=0.0001), with a risk of 44.1% in patients with both. However, the on-treatment virological response was high. CONCLUSIONS The safety profile was poor and patients with platelet count ≤ 100,000/mm(3) and serum albumin <35 g/L should not be treated with the triple therapy.

Advances in the development of nucleoside and nucleotide analogues for cancer and viral diseases

Nucleoside analogues have been in clinical use for almost 50 years and have become cornerstones of treatment for patients with cancer or viral infections. The approval of several additional drugs over the past decade demonstrates that this family still possesses strong potential. Here, we review new nucleoside analogues and associated compounds that are currently in preclinical or clinical development for the treatment of cancer and viral infections, and that aim to provide increased response rates and reduced side effects. We also highlight the different approaches used in the development of these drugs and the potential of personalized therapy.

Antiviral drug-resistant HBV: standardization of nomenclature and assays and recommendations for management.

Substantial advances have been made in the treatment of chronic hepatitis B in the past decade. Approved treatments for chronic hepatitis B include 2 formulations of interferon and 4 nucleos(t)ide analogues (NAs). Sustained viral suppression is rarely achieved after withdrawal of a 48‐week course of NA therapy, necessitating long, and in many cases, indefinite treatment with increasing risk of development of drug resistance. Antiviral resistance and poor adherence are the most important factors in treatment failure of hepatitis B. Thus, there is a need to standardize nomenclature relating to hepatitis B antiviral resistance, and to define genotypic, phenotypic, and clinical resistance to NA therapy. (HEPATOLOGY 2007;46:254–265.)

The way forward in HCV treatment--finding the right path.

Infection with the hepatitis C virus (HCV) represents an important health-care problem worldwide. The prevalence of HCV-related disease is increasing, and no vaccine is yet available. Since the identification of HCV as the causative agent of non-A, non-B hepatitis, treatment has progressed rapidly, but morbidity and mortality rates are still predicted to rise. Novel, more efficacious and tolerable therapies are urgently needed, and a greater understanding of the viral life cycle has led to an increase in the number of possible targets for antiviral intervention. Here we review the specific challenges posed by HCV, and recent developments in the design of vaccines and novel antiviral agents.

Susceptibility to antivirals of a human HBV strain with mutations conferring resistance to both lamivudine and adefovir

Mutations within the hepatitis B virus (HBV) polymerase gene conferring drug‐resistance are selected during prolonged lamivudine (3TC) or adefovir dipivoxil (ADV) treatment. Because there is no other approved drug against HBV, treatments with 3TC or ADV are used either sequentially or in addition, depending on treatment response or failure. Considering the use of de novo or add‐on 3TC+ADV bitherapy, we investigated the possibility of the emergence of an HBV strain harboring polymerase mutations conferring resistance to both 3TC (rtL180M+M204V) and ADV (rtN236T). We constructed the L180M+M204V+N236T mutant and determined its replication capacity and its susceptibility to different nucleos(t)ide analogs in transiently transfected hepatoma cell lines. The triple mutant replicates its genome in vitro, but less efficiently than either the wild‐type (wt) HBV or L180M+M204V and N236T mutants. Phenotypic assays indicated that the L180M+M204V+N236T mutant is resistant to pyrimidine analogs (3TC, ‐FTC, β‐L‐FD4C, L‐FMAU). Compared with wt HBV, this mutant displays a 6‐fold decreased susceptibility to ADV and entecavir and a 4‐fold decreased susceptibility to tenofovir. Interferon alfa inhibited equally the replication of wt and L180M+M204V+N236T HBV. In conclusion, the combination of rtL180M+M204V and rtN236T mutations impairs HBV replication and confers resistance to both 3TC and ADV in vitro. These results suggest that the emergence of the triple mutant may be delayed and associated with viral resistance in patients treated with 3TC+ADV. However, other nucleos(t)ide analogs in development showed an antiviral activity against this multiresistant strain in vitro. This provides a rationale for the clinical evaluation of de novo combination therapies. (HEPATOLOGY 2005;41:1391‐1398.)

Comparison of 1 or 3 MU of interferon alfa-2b and placebo in patients with chronic non-A, non-B hepatitis

Ninety patients with histologically documented chronic non-A, non-B hepatitis were randomly allocated to receive SC injections of placebo or of 1 or 3 MU of recombinant interferon alfa-2b three times weekly for 24 weeks. Complete normalization of alanine aminotransferase levels occurred posttreatment in 43.3% of patients receiving 3 MU, in 20% of those receiving 1 MU, and in 6.7% of untreated patients (P less than 0.0005 vs. those treated with 3 MU). Alanine aminotransferase normalization was sustained for 6 months after therapy in 13.3% of the patients treated with 3 MU and in 3.3% of those given 1 MU or placebo. The decline of alanine aminotransferase levels following interferon therapy showed independent, positive correlations with female sex (P less than 0.03) and younger age (P less than 0.05). The Knodells fibrosis score was strongly positively correlated with age (P less than 0.0001). It is concluded that 3 MU of interferon is a more effective dose than 1 MU for controlling disease activity in non-A, non-B chronic hepatitis patients. Women and younger and noncirrhotic patients are more likely to respond.