Antiviral efficacy analysis of telbivudine concurrent with the first cycle of chemotherapy in HBsAg-positive lymphoma patients

Hepatitis B reactivation: diagnosis and management

INTRODUCTION

Hepatitis B virus (HBV) reactivation can be induced by treatments that attenuate the immunological control over HBV, leading to increased morbidity and mortality. The risk of HBV reactivation is determined by host immunity, viral factors, and the type and dose of treatments. Nevertheless, the risk of HBV reactivation for a growing number of novel therapies remains uncertain and needs to be carefully examined. Identification of patients at risk and administration of prophylactic antiviral agents are critical to prevent HBV reactivation. Early diagnosis and initiation of antiviral treatment are the keys to avoid devastating outcomes.

AREA COVERED

We summarized the latest evidence and recommendations for risk stratification, early diagnosis, prophylaxis, and management of HBV reactivation.

EXPERT OPINION

Universal screening, adequate prophylaxis, and close monitoring are essential for the prevention of HBV reactivation. Risk stratification of patients at risk with appropriate antiviral prophylaxis can prevent HBV reactivation effectively. Several emerging biomarkers have been proved to help determine the risk precisely. Early detection and timely administration of antiviral agents are crucial for management. Further studies on the precision of risk stratification as well as the optimal duration of prophylaxis and treatment are needed to establish an individualized strategy.

Efficacy of telbivudine and entecavir against virus reactivation in HBeAg-patients undergoing chemotherapy

The renal protective effect of telbivudine (LdT) was verified by a previous meta-analysis. It was left unclear, however if this effect offsets the associated risk of virological breakthrough in hepatitis B e-antigen-negative (HBeAg-) patients receiving chemotherapy (C/T).Records of 260 HBeAg-, non-cirrhotic cancer patients undergoing systemic C/T with prophylactic LdT or entecavir (ETV) were retrospectively investigated. The investigation was conducted 6 months after completion of C/T, patient death from cancer, or antiviral modification. Treatment duration, outcome, change of renal function, and reason for antiviral modification were analyzed. The primary endpoint was the occurrence of virological breakthrough during prophylaxis C/T and the change in renal function.Of the 126 HBeAg- patients treated with LdT, 3 (2.38%) experienced HBV virological breakthroughs, whereas none of the patients treated with ETV (P = .07) did. The estimated glomerular filtration rate for the patients treated with LdT was essentially unaltered, decreasing only slightly from 87.5 ± 23.1 to 87.3 ± 21.3 ml/minute/1.73 m (P = .55), while the rate for the ETV-treated patients was significantly lowered from 95.7 ± 32.2 to 85.5 ± 85.7 ml/minute/1.73 m (P = .0009).The absolute risk reduction ARR is 27.8% - 21.2% = 6.6%, comparing ETV with LdT for reduction of renal function impairment and the absolute risk increase for virological breakthrough during C/T, the absolute risk increase (ARI) is 2.38% - 0% = 2.38%. The overall likelihood of being helped over being harmed was 2.77. With careful selection of patients with the criteria of HBeAg-status and non-hematologic cancer, it is feasible that telbivudine raise lower probability of virological breakthroughs during prophylaxis treatment.

Prevention and management of hepatitis B virus reactivation in patients with hematological malignancies treated with anticancer therapy

Hepatitis due to hepatitis B virus (HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, especially rituximab-containing therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen (HBsAg) and antibody to hepatitis B core antigen (anti-HBc). Patients found to be positive for HBsAg should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving high-risk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBsAg-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies.

High titers of anti-HBs prevent rituximab-related viral reactivation in resolved hepatitis B patient with non-Hodgkin's lymphoma

Rituximab, an anti-CD20 monoclonal antibody, is associated with an increased risk of hepatitis B virus (HBV) reactivation. This study aimed to determine the predictive factors for rituximab-related HBV reactivation in resolved hepatitis B patients, defined as HBsAg-negative, anti-HBc-positive, and undetectable HBV DNA. Among 840 consecutive patients with CD20-positive B-cell lymphoma who received rituximab-based chemotherapy from 2003 through 2014 at Seoul National University Hospital, 732 patients were excluded because either anti-HBc was not assessed or they were HBsAg-seropositive. This retrospective study included 108 resolved hepatitis B patients. During a median 33.5-month follow-up period, eight cases of HBV reactivation occurred only among the patients with low anti-HBs titers (<100 mIU/ml) at baseline and those who did not receive antiviral prophylaxis. Using multivariate analyses, antiviral prophylaxis and baseline anti-HBs titers were the protective factors for HBV reactivation (hazard ratio [HR], 0.90 and 0.95, respectively). Among those who did not receive antiviral prophylaxis, patients with high baseline anti-HBs (≥100 mIU/ml) experienced significantly lower risk of HBV reactivation (HR, 0.49; P = 0.006) than the patients with low baseline anti-HBs (<100 mIU/ml) whose cumulative HBV reactivation rates at 6 and 24 months after chemotherapy were 8.3% and 17.3%, respectively. High anti-HBs titer at baseline and antiviral prophylaxis prevented HBV reactivation, suggesting antiviral prophylaxis should be considered according to baseline anti-HBs titer. Meticulous follow-up for ALT and HBV DNA without antiviral prophylaxis might be possible for the patients with high baseline anti-HBs (≥100 mIU/ml).

Cost-effectiveness analysis of lamivudine, telbivudine, and entecavir in treatment of chronic hepatitis B with adefovir dipivoxil resistance

The purpose of this study was to analyze the cost-effectiveness of lamivudine (LMV), telbivudine (LdT), and entecavir (ETV) in treatment of chronic hepatitis B with adefovir dipivoxil (ADV) resistance. Two hundred and fifty-two patients were recruited and screened for resistance to ADV and randomly assigned into three groups: LMV + ADV, LdT + ADV, and ETV + ADV. The ratio of biochemical response, virological response, seroconversion of hepatitis Be antigen (HBeAg)/hepatitis Be antibody (HBeAb), viral breakthrough, and the cost and effectiveness of treatments were analyzed. A comparison of the results of the ratio of biochemical response, virological response and seroconversion of HBeAg/HBeAb, showed no statistical difference between the three groups, with the economic cost of LMV + ADV the lowest, LdT + ADV the middle, and ETV + ADV the highest. The side effects of the three plans are all rare and tolerable. LMV + ADV is the optimal rescue strategy, and LdT + ADV the alternative selection in the economically less developed regions, while ETV + ADV was used in the economically developed regions.