Extended treatment with lamivudine and adefovir dipivoxil in chronic hepatitis B patients with lamivudine resistance

Adverse events of nucleos(t)ide analogues for chronic hepatitis B: a systematic review

Nucleos(t)ide analogues (NAs) are the main drug category used in chronic hepatitis B (CHB) treatment. Despite the fact that NAs have a favourable safety profile, undesired adverse events (AEs) may occur during the treatment of CHB. Given the eminent number of patients currently receiving NAs, even a small risk of any of these toxicities can represent a major medical issue. The main objective of this review was to analyse information available on AEs associated with the use of NAs in published studies. We choose the following MesH terms for this systematic review: chronic hepatitis B, side effects and treatment. All articles published from 1 January 1990 up to 19 February 2018 in MEDLINE of PubMed, EMBASE, the Cochrane Library and LILACS databases were searched. A total of 120 articles were selected for analysis, comprising 6419 patients treated with lamivudine (LAM), 5947 with entecavir (ETV), 3566 with tenofovir disoproxil fumarate (TDF), 3096 with telbivudine (LdT), 1178 with adefovir dipivoxil (ADV) and 876 with tenofovir alafenamide (TAF). The most common AEs in all NAs assessed were abdominal pain/discomfort, nasopharyngitis/upper respiratory tract infections, fatigue, and headache. TAF displays the highest density of AEs per patient treated among NAs (1.14 AE/treated patient). In conclusion, treatment of CHB with NAs is safe, with a low incidence of AEs. Despite the general understanding TAF being safer than TDF, the number of patients treated with TAF still is too small in comparison to other NAs to consolidate an accurate safety profile. PROSPERO Registration No. CRD42018086471.

Compare with safety and efficacy of entecavir and adefovir dipivoxil combination therapy and tenofovir disoproxil fumarate monotherapy for chronic hepatitis B patient with adefovir-resistant

Objective: To compare the 2-year efficacy and safety of combination therapy with entecavir (ETV) and adefovir dipivoxil (ADV) to that of tenofovir disoproxil fumarate (TDF) monotherapy in treatment of patients with adefovir drug-resistant chronic hepatitis B. Methods: HBeAg-positive CHB patients (n = 100) with adefovir-resistance (rtA181T/V and/or rtN236T) were enrolled. Patients were treated with either ETV 0.5 mg plus ADV 10 mg per day (n = 52) or TDF 300 mg per day (n = 48) for 48 weeks. Tests for liver and kidney function, Serum Phosphorus, HBV serum markers, HBV DNA load and ultrasonography of liver were performed every 3 months. Student's t-test and χ² test were used to compare the efficacy, side effects in the two groups. Results: Fifty-two patients in ETV + ADV group and forty-eight patients in TDF group were followed-up for 96 weeks. HBV DNA undetectable rate were 76.9% versus 81.3% (P = 0.631) at week 48, and 92.3% versus 95.8% (P = 0.679) at week 96 in ETV + ADV combination therapy and TDF monotherapy group respectively. Serum ALT normalized rate were 84.6% versus 87.5% (P = 0.777) at week 48, and 92.3% versus 95.8% (P = 0.679) at week 96 in ETV+ADV combination therapy and TDF monotherapy group respectively. But the level of serum Phosphorus was significantly lower in ETV + ADV combination therapy group compare with TDF monotherapy group (1.13 ±0.15 versus 1.22 ±0.16, P = 0.004) at week 96. Conclusion: Both ETV + ADV combination therapy and TDF monotherapy provided effective treatments in chronic hepatitis B with adefovir-resistant. However, it was associated with poor serological responses up to week 96. The long term treatment of hepatitis B with ETV (0.5 mg/day) combination of ADV (10 mg/day) can potentially cause hypophosphatemia and renal impairment, so regular monitoring of serum phosphate, serum creatinine and evaluation of eGFR is needed.

Efficacy of Tenofovir-based Rescue Therapy in Lamivudine-resistant Chronic Hepatitis B Patients With Failure of Lamivudine and Adefovir Combination

PURPOSE

In chronic hepatitis B patients, lamivudine (LAM) and adefovir (ADV) combination therapy is commonly used as a rescue therapy for LAM resistance, but it often results in incomplete viral suppression. We investigated the antiviral efficacy of tenofovir (TDF)/LAM combination therapy versus TDF monotherapy in LAM-resistant chronic hepatitis B (CHB) patients who failed to respond to LAM plus ADV rescue therapy.

METHODS

Among 108 patients with LAM-resistant CHB who had a partial virologic response (VR) to LAM and ADV combination therapy, Eighty one patients were finally included in this study.

FINDINGS

Resistance to ADV (ADV-R) was present in 32 patients (39.5%), and the remaining 49 patients (60.5%) had a partial virologic response to LAM/ADV combination (ADV-P). The study subjects were treated with TDF alone (n=15) or TDF/LAM combination (n=66). VR was achieved in 61 patients (75.3%). The rates of VR at 6 and 12 months were not significantly different between TDF monotherapy and TDF/LAM combination therapy groups (46.7 vs. 68.2% at 6 months, and 66.7 vs. 75.9% at 12 months, log-rank P=0.357). Treatment efficacy of TDF alone or TDF/LAM combination was not statistically different according to pre-existing ADV or LAM resistant strains. In multivariate analysis, absolute HBV DNA levels at the start of TDF rescue treatment (P<0.001; OR, 0.556; 95% CI, 0.422-0.731) were the only significantly associated with VR.

IMPLICATIONS

TDF monotherapy was as effective as TDF/LAM combination therapy in maintaining viral suppression in patients with LAM-resistant patients who failed to respond to LAM/ADV combination therapy.

Randomized comparison of tenofovir disoproxil fumarate vs emtricitabine and tenofovir disoproxil fumarate in patients with lamivudine-resistant chronic hepatitis B

BACKGROUND & AIMS

Tenofovir disoproxil fumarate (TDF) is active against lamivudine-resistant hepatitis B virus (HBV) infection, but data to support its clinical efficacy in this setting are limited.

METHODS

In a prospective, double-blind, 96-week trial, patients were randomly assigned (1:1) to groups given TDF (300 mg, n = 141) or a combination of emtricitabine (FTC, 200 mg; n = 139) and TDF (300 mg, FTC/TDF). Patients were hepatitis B e antigen (HBeAg)-positive or HBeAg-negative, with levels of HBV DNA ≥3 log10 IU/mL and lamivudine resistance mutations (HBV polymerase or reverse transcriptase amino acid substitutions rtM204I/V ± rtL180M by INNO-LiPA Multi-DR v3; Innogenetics, Inc, Alpharetta, GA). The primary end point was proportion with HBV DNA <69 IU/mL (Roche COBAS Taqman assay; Roche Molecular Systems, Inc, Pleasanton, CA).

RESULTS

Patient groups were well matched for demographic and disease characteristics, including region (60% from Europe), HBV genotype (45% genotype D), HBeAg status (47% HBeAg-positive), and duration of lamivudine treatment (mean, 3.8 years). At week 96 of treatment, 89.4% of patients in the TDF group and 86.3% in the FTC/TDF group had levels of HBV DNA <69 IU/mL (P = .43). HBeAg loss and seroconversion did not differ between groups; only 1 patient (0.7%) in the FTC/TDF group lost hepatitis B surface antigen. Treatment was well tolerated; confirmed renal events (creatinine increase of ≥0.5 mg/dL [>44 umol/L], creatinine clearance <50 mL/min, or level of PO4 <2 mg/dL [<0.65 mmol/L]) were generally mild and infrequent (<1%). Small reductions (<2%) in mean bone mineral density of hip and spine were detected by dual-energy x-ray absorptiometry in both groups. No TDF resistance developed through 96 weeks of treatment.

CONCLUSIONS

TDF alone is safe and effective for treatment of patients with lamivudine-resistant, chronic HBV infection. Clinical Trials.gov No, NCT00737568.

Two rescue therapies in lamivudine-resistant patients with chronic hepatitis B in the central China: adefovir monotherapy and adefovir plus lamivudine

The emergence of mutations that confer drug resistance in patients with chronic hepatitis B (CHB) is increasing in China. We aimed to compare the cumulative efficacy and resistance of adefovir (ADV) monotherapy and ADV add-on lamivudine (LAM) (ADV+LAM) therapy in LAM-resistant patients. One-hundred adult CHB patients with LAM-resistance mutations were identified. Of these 100, 52 patients were treated with ADV monotherapy and 48 were treated with ADV+LAM combination therapy for at least 24 months. After 2-year treatment, the cumulative rates of serum alanine aminotransferase normalization were, respectively, 73.1 and 83.3 % in the ADV monotherapy and ADV+LAM therapy groups (P = 0.216). Additionally, 36 patients receiving ADV plus LAM had hepatitis B e antigen loss/seroconversion, as compared with 30 in patients (P = 0.068). More patients who received LAM plus ADV than those who received ADV alone had HBV DNA levels below 1,000 international unit/milliliters (83.3 vs. 50 %, P < 0.001). Viral breakthrough and genotypic mutations were detected in 19 (36.5 %) and 9 (18.8 %) patients in the ADV monotherapy and ADV+LAM therapy groups, respectively (P = 0.048). ADV+LAM combination therapy demonstrated faster and significantly greater suppression of HBV DNA compared with ADV therapy alone for patients with LAM-resistance mutations. ADV+LAM was superior to ADV monotherapy in achieving the initial viral breakthrough and genotypic mutations. ADV+LAM combination therapy was rational for most of LAM-resistant Chinese patients with chronic hepatitis B.

Update on rescue therapies in patients with lamivudine-resistant chronic hepatitis B

Chronic hepatitis B continues to be a global problem, with an estimated 240 million cases according to the World Health Organization. Chronic infection with the hepatitis B virus (HBV) is associated with cirrhosis, hepatic decompensation, and hepatocellular carcinoma. There are currently several US Food and Drug Administration-approved medications for treating chronic hepatitis B, with Lamivudine (LAM) being the first oral agent made available. The major problem with LAM is significantly decreased effectiveness over time due to the development of anti-HBV resistance that can lead to virologic and biochemical breakthrough as well as hepatitis B flare, progression of liver disease, and decompensation of pre-existing cirrhosis. Despite its high anti-HBV resistant rate, LAM remains widely used in underdeveloped countries due to its wide availability and low cost compared to other antiviral medications, including those that are more effective. Therefore, it is still clinically important to learn how to prevent and treat LAM resistant strains of HBV. Several regimens with the other available antiviral agents have been studied, including switching to monotherapy with either Adefovir, Entecavir, or Tenofovir, adding Adefovir to LAM, and switching to a combination of Adefovir and Entecavir. This review article will examine molecular mechanisms and diagnosis of LAM anti-HBV resistance, risks for and approaches to reduce LAM anti-HBV resistance, and currently available rescue therapy regimens for LAM resistance.

Entecavir and hepatitis B immune globulin in patients undergoing liver transplantation for chronic hepatitis B

For patients undergoing liver transplantation (LT) for hepatitis B virus (HBV)-related liver disease, the current standard of care for preventing reinfection of the allograft is nucleoside analogue therapy combined with hepatitis B immune globulin (HBIG). Entecavir has demonstrated high efficacy and a favorable safety profile for chronic hepatitis B (CHB) treatment, but data for patients undergoing HBV-related LT are limited. This study assessed the safety and efficacy of entecavir combined with various HBIG regimens after CHB-related LT. In this phase 3b, single-arm, open-label study, 65 patients undergoing LT for CHB-related liver disease with an HBV DNA load <172 IU/mL at LT received entecavir (1.0 mg daily) for 72 weeks after LT. The primary endpoint was the proportion of evaluable patients (treated for ≥4 weeks) with virological recurrence (HBV DNA level ≥50 IU/mL) through week 72. Concomitant HBIG therapy was received by 64 of the 65 enrolled patients, and 44% of these patients received high-dose HBIG (any HBIG dose in the specified interval ≥10,000 IU). Through week 72, all 61 patients evaluable for the efficacy analysis had undetectable HBV DNA. The Kaplan-Meier estimate of patients without hepatitis B surface antigen (HBsAg) recurrence at week 72 was 0.9655. Two patients experienced a reappearance of HBsAg, but both remained HBV DNA(-) until the last follow-up. The frequency and nature of adverse events were consistent with those expected for this patient population. Serum creatinine increments ≥0.3 mg/dL and ≥0.5 mg/dL occurred in 62% and 39% of the patients, respectively, and all of these patients received calcineurin inhibitor therapy. In conclusion, in this population of patients treated with entecavir after CHB-related LT, entecavir was well tolerated and effective in maintaining viral suppression, even in individuals who experienced a reappearance of HBsAg.

Efficacy and Safety of Telbivudine Compared to Entecavir Among HBeAg+ Chronic Hepatitis B Patients: a Meta-Analysis Study

BACKGROUND

Hepatitis B virus (HBV) infection is a serious global health problem that is associated with huge social and economic costs. Early antiviral drugs, such as interferon-α2b, peginterferon-α2a, lamivudine, and adefovir, all have their limitations (such as low responses or safety concerns) in clinical application. Telbivudine and entecavir are two of the latest nucleotide drugs and both have been shown to have potent viral suppression. However, in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB), inconsistent results have been generated for efficacy between telbivudine and entecavir. Therefore, evidence-based medical data are required to compare the efficacies, in terms of virological and biochemical responses, and safety between telbivudine and entecavir.

OBJECTIVES

We aimed to compare the early antiviral efficacy and safety of telbivudine and entecavir in the treatment of patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB).

PATIENTS AND METHODS

A search for relevant randomized controlled trials (RCTs) on HBeAg-positive CHB patients treated with telbivudine and entecavir for 24 or 52 weeks, published before December 2011, was performed. Primary efficacy endpoint was the cumulative rate of undetectable HBV DNA, and secondary efficacy endpoints included rates of alanine aminotransferase (ALT) normalization, HBeAg disappearance, HBeAg seroconversion and adverse events. Meta-analysis was performed using the Review Manager v5.1.4 software package. We assessed the pooled risk ratios (RRs) and 95% confidence intervals (CIs) using the fixed-or random-effects model.

RESULTS

Six randomized controlled trials (RCTs) involving 555 patients were included. Telbivudine was associated with significantly higher rates of HBeAg disappearance (RR = 1.46, 95% CI: 1.11 - 1.91) and HBeAg seroconversion (RR = 1.76, 95%CI: 1.25-2.48) than entecavir, but had higher adverse events (RR = 2.11, 95%CI: 1.23 - 3.60), compared with entecavir. There was no difference between telbivudine and entecavir in the rate of cumulative undetectable HBV DNA (RR = 0.99, 95% CI: 0.90 - 1.10) and ALT normalization (RR = 0.93, 95% CI: 0.85 - 1.00).

CONCLUSIONS

Telbivudine is associated with significantly higher rates of HBeAg disappearance and HBeAg seroconversion than entecavir, whereas entecavir is superior to telbivudine in safety. Both drugs have similar efficacy on rates of cumulative undetectable HBV DNA and ALT normalization.

Comparison of rescue strategies in lamivudine-resistant patients with chronic hepatitis B

Lamivudine (LAM) resistance now poses a major problem in the management of patients with chronic hepatitis B virus (HBV) infection. We retrospectively collected clinical data on chronic HBV-infected patients who had developed LAM resistance under de novo LAM monotherapy and subsequently took nucleos(t)ide analogs as rescue strategy in our hospital. From initiation of rescue therapies to January 2012, incidence of antiviral drug resistance was 23.67%, 18%, 6.94% and 0% (P=0.007) in the group of switching to adefovir dipivoxil (ADV) monotherapy, switching to entecavir (ETV) monotherapy, adding on ADV and switching to combination of ADV and ETV. At month 12, the median levels of serum HBV DNA were respectively 9300IU/mL, 4648IU/mL, 2054IU/mL and 100IU/mL (P<0.001), and the cumulative rates of serum ALT normalization were respectively 75%, 84%, 93% and 100% (P=0.003). Additionally, the strategy of switching to ADV monotherapy induced more single rtA181T mutations. In conclusion, switching to ADV monotherapy has been widely used in real-world clinical practice in China, however, due to the high incidence of drug resistance, switching to neither ADV nor ETV monotherapy is optimal when LAM resistance occurs; combination of ADV and ETV is most effective, whereas the strategy of adding on ADV is rational for most of LAM-resistant Chinese patients with chronic hepatitis B.