Mutations associated with drug resistance and prevalence of vaccine escape mutations in patients with chronic hepatitis B infection.

The Brazilian public health system (SUS) has provided antiviral drugs for chronic hepatitis B treatment for over 10 years, but a system for monitoring for drug-related resistance mutations is not available. Determine the presence of HBV mutations associated with resistance to nucleos(t)ide analogs among 81 patients with chronic HBV infection in Salvador-BA-Brazil. HBV-DNA was PCR amplified with primers deduced from the rt domain at the HBV P gene, the sequence extended 1032 bp (from amino acid 1 to 344-rt domain). Those sequences were submitted to the HBV drug resistance database to retrieve each mutation according to the genotype. HBV genotype A1 (85.2%) was the most prevalent, followed by genotype A2 (4.9%), F (6.2%), and C1, D2, and D4 (1.2% each). Six patients (7%) exhibited resistance mutations to LAM, ETV, and TDF: two with patterns L180M + M204V and four with other different patterns: L80I + L180M + M204I; L80V + L180M + M204V; M204I; A194T. All of these mutations were present in patients with genotype A (four A1 and two A2). In addition, four mutations in gene S (three cases with the sI195M mutation and one with the W196L mutation), were detected, corresponding to a rate of 6% of vaccine escape mutations. Althougth the small sample size, an association was found between the occurrence of HBV resistance mutations and HBeAg positivity, co-infection with HIV and a history of treatment for HBV and/or HIV.

Telbivudine therapy for chronic hepatitis B: A journey to identify super-responders and to optimize treatment using the roadmap model.

Hepatitis B virus (HBV) infection is one of the most serious health problems worldwide with a high risk for cirrhosis and liver cancer. Several antiviral agents have been approved for the treatment of chronic hepatitis B, leading to a rapid reduction in HBV DNA and normalization of serum alanine aminotransferase levels. Telbivudine, a potent inhibitor of HBV replication, has been shown to be well tolerated. Because of the emergence of drug resistance, optimization strategies for telbivudine therapy have been shown to improve patient responses. Optimal baseline characteristics in so-called super-responders have been used to predict the virological response. Baseline HBV DNA levels < 9 log10 copies/mL (2 × 108 IU/mL) or alanine aminotransferase levels of more than or equal to twofold the upper limit of normal in HBeAg-positive patients and HBV DNA < 7 log10 copies/mL (2 × 106 IU/mL) in HBeAg-negative patients were strong predictors for virological response. In addition, the roadmap model, based on early virological response at week 24 of therapy, is considered as a powerful tool to identify patients at risk of treatment failure (HBV DNA ≥ 300 copies/mL, i.e. 60 IU/mL) and to reduce the risk of antiviral resistance. When considering pre-treatment characteristics and on-treatment responses, telbivudine may provide physicians with a wide choice of options to effectively treat patients with chronic hepatitis B, especially those with or at risk of renal impairment, or women of childbearing age.

Management of patients with overt or resolved hepatitis B virus infection undergoing rituximab therapy.

INTRODUCTION: Rituximab (RTX), a chimeric mouse anti-human CD20 monoclonal antibody, is indicated for the treatment of patients with non-Hodgkin's lymphoma, chronic lymphocytic leukemia, granulomatosis with polyangiitis and microscopic polyangiitis, and rheumatoid arthritis, but nowadays it is increasingly used for the treatment of many other immune-mediated disorders. Hepatitis B virus (HBV) reactivation in RTX-treated patients, eventually leading to fatal liver failure, has been reported more often among hepatitis B surface antigen (HBsAg)-positive patients (overt infection) than in HBsAg-negative, antibody to hepatitis B core antigen (anti-HBc) seropositive patients (resolved infection). AREAS COVERED: This paper reviews the safety of RTX in patients with overt or resolved HBV infection, providing recommendations for its safe use in such patients. EXPERT OPINION: Prior to starting RTX treatment, all patients should be screened for HBV infection. While HBsAg-positive active carriers should receive long-term antiviral treatment with entecavir (ETV) or tenofovir, inactive carriers are candidates for universal prophylaxis with lamivudine, or ETV or tenofovir in selected cases, to prevent hepatitis reactivation. Conversely, for HBsAg-negative anti-HBc positive carriers, that is, those with resolved HBV infection, universal prophylaxis with lamivudine is recommended for those with onco-hematological diseases, whereas watchful monitoring of HBsAg/HBV DNA levels is advisable for all the other indications.

Perfil das mutações de resistência do vírus da Hepatite B aos análogos de nucleos(t)ídeos entre pacientes com hepatite B crônica / Profile of resistance mutations of hepatitis B virus to analogs of nucleos (t) ide among patients with chronic hepatitis B

Introdução: A doença causada pelo vírus da hepatite B (HBV) é um problema de saúde pública mundial. No Brasil, o sistema único de saúde (SUS) tem disponibilizado drogas antivirais para o tratamento de hepatite B crônica há mais de 10 anos, mas um sistema para o monitoramento e avaliação de resistência a estas drogas ainda não está disponível. Objetivo: Este estudo teve como objetivo determinar o perfil de mutações do HBV associadas com a resistência aos análogos de nucleos(t)ídeos entre 81 pacientes com infecção crônica pelo HBV: virgens de tratamento para hepatite B e tratados com diferentes análogos de nucleosídeos e nucleotídeos, no Hospital Professor Edgar Santos (HUPES-UFBA)- Salvador-BA. Metodologia: O HBV-DNA foi isolado de amostras de soro, amplificado por nested-PCR, utilizando-se primers deduzidos da região flaqueadora da domínio rt do gene P e sequenciados (ABI Prism 3730, Applied Biosystems, EUA). Duas a seis sequências de cada isolado foram alinhados e os sítios conflitantes foram resolvidos usando o software CLC Main Workbench v. 5.0 por inspeção visual dos eletroferogramas. As sequências consenso tinham um tamanho de 1032 pb (compreendendo os aminoácido 1-344 da rt)...

Introduction: Hepatitis B virus (HBV) infection is a public health issue. The Brazilian public health system (SUS) has provided antiviral drugs for chronic hepatitis B treatment for over 10 years, but a system for monitoring for drug-related resistance mutations is not available. Objective: This study aims to determine the presence of HBV mutations associated with resistance to nucleos(t)ide analogs among 81 patients with chronic HBV infection-naïve and treated from University Hospital Professor Edgard Santos, Salvador-BA (HUPES-UFBA). Methods: Briefly, HBV-DNA was PCR amplified with primers deduced from the flanking of the rt domain at the HBV P gene and sequenced using ABI Prism 3730 (Applied Biosystems, USA). From two to six forward and reverse sequences of each isolate were assembled and conflicting sites were resolved using software CLC Main Workbench v. 5.0 by visual inspection of the electropherograms. Consensus sequence extended 1032 bp and encompassed the entire rt domain (from amino acid 1 to 344)...