Comparison between clevudine and entecavir treatment for antiviral-naïve patients with chronic hepatitis B

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.

Tenofovir is superior to entecavir for achieving complete viral suppression in HBeAg-positive chronic hepatitis B patients with high HBV DNA

BACKGROUND

Entecavir (ETV) and tenofovir disoproxil fumarate (TDF) are the two first-line anti-viral therapies for chronic hepatitis B (CHB); however, there are limited studies directly comparing their effectiveness.

AIM

To compare the effectiveness of ETV and TDF in nucleos(t)ide-naïve CHB patients with high hepatitis B virus (HBV) DNA levels, defined as serum HBV DNA greater than 6 log10  IU/mL.

METHODS

We performed a retrospective multicentre cohort study of adult CHB patients who were seen between 2009 and 2012 at four Northern California community gastroenterology and hepatology clinics.

RESULTS

We identified 59 consecutive patients treated with TDF and 216 patients treated with ETV. Pre-treatment characteristics were similar between the two groups. Among HBeAg-negative patients, there was no significant difference in viral suppression rates between ETV and TDF (P = 0.72). In contrast, among HBeAg-positive patients, those treated with TDF achieved viral suppression significantly more rapidly than those treated with ETV (P < 0.0001); the Kaplan-Meier estimated probability of complete suppression was 18% vs. 11% at 6 months, 51% vs. 28% at 12 months and 72% vs. 39% at 18 months respectively. Multivariate Cox proportional hazards analysis indicated that treatment with TDF compared to ETV was a significant predictor of viral suppression, but only for HBeAg-positive patients (HR = 2.59; 95% CI 1.58-4.22; P < 0.001).

CONCLUSION

Tenofovir is significantly more effective than entecavir for achieving complete viral suppression in HBeAg-positive, nucleos(t)ide-naïve chronic hepatitis B patients with HBV DNA greater than 6 log10  IU/mL.

[Efficacy of entecavir switching therapy in chronic hepatitis B patients with clevudine-induced myopathy]

BACKGROUND/AIMS

Clevudine is a potent antiviral agent against HBV. However, long-term clevudine therapy may cause myopathy. This study was carried out to identify the efficacy of entecavir switching therapy in chronic hepatitis B patients experiencing clevudine-induced myopathy.

METHODS

One hundred forty six patients with chronic hepatitis B treated with 30 mg of clevudine per day for 73 weeks (range, 36-132 weeks) were enrolled. Among them, clevudine-induced myopathy occurred in 21 patients (14.4%) which was diagnosed if the patients had symptoms related to myopathy with concurrent CK and AST elevation. All the patients who were diagnosed as clevudine-induced myopathy stopped the therapy, and 17 patients (81%) were switched to entecavir 0.5 mg.

RESULTS

The patients with clevudine-induced myopathy were switched to entecavir 0.5 mg for median 68 weeks, and all of them showed disappearance of clinical myopathic symptoms and normalization of CK and AST level within median 2.2 months. Eight patients (47%) were HBeAg positive before entecavir treatment, and HBeAg seroconversion was achieved in 2 patients (25%). HBV DNA level was elevated in 3 patients (17.6%) at the time when the patients were diagnosed as myopathy, all of them achieved virological response with entecavir switching therapy. ALT level was elevated in 3 patients (17.6%) before entecavir treatment, all of them showed normalization of ALT level. During entecavir therapy, genotypic resistance to entecavir or virological breakthrough was not noted.

CONCLUSIONS

In chronic hepatitis B patients experiencing clevudine-induced myopathy, switching to entecavir 0.5 mg per day showed a resolution of myopathy and adequate viral suppression.

Virological Response and Muscular Adverse Events during Long-Term Clevudine Therapy in Chronic Hepatitis B Patients

BACKGROUND

Recently, several reports issued clevudine induced myopathy in the long term use.

OBJECTIVES

The aim of this study was to investigate antiviral effects and adverse events of clevudine monotherapy in patients with chronic hepatitis B (CHB).

PATIENTS AND METHODS

The subjects were 110 treatment-naïve CHB patients. They were treated with 30 mg clevudine/day for more than six months. Virological and biochemical tests, including that for serum creatine kinase (CK), were monitored at baseline and at 3-month intervals during treatment period.

RESULTS

In HBeAg-positive patients, the cumulative rates of virological response were 74.0 %, 68.5 %, and 67.3 % after one, two, and three years of clevudine treatment, respectively. Cumulative rates of HBeAg loss or seroconversion were 17.8 %, 30 %, and 31.5 % after one, two and, three years of clevudine treatment, respectively. In HBeAg-negative patients, the cumulative rates of virological response were 97.3 %, 100 %, and 94.6 %, respectively. Virological breakthrough occurred in 27 patients. The rtM204I mutation in HBV polymerase was predominantly detected. Muscular adverse events were observed in 15 patients. All patients with myopathy recovered after the cessation of clevudine monotherapy. Fluctuations in CK level during the clevudine treatment period were frequently observed irrespective of development of myopathy. Multiple episodes of CK elevation were significantly related to the development of myopathy.

CONCLUSIONS

Long-term clevudine monotherapy is effective for suppression of serum HBV DNA level and normalization of serum alanine amino transaminase levels, but associated with occurrence of rtM204I mutation. Clevudine-induced muscular adverse events are not uncommon, although they are totally reversible after cessation of the treatment. Muscular adverse events and serum CK level should be carefully monitored during long-term treatment with clevudine.

Two cases of telbivudine-induced myopathy in siblings with chronic hepatitis B

Telbivudine is an L-nucleoside analogue with potent antiviral activity against hepatitis B virus (HBV). Clinical trials have shown that telbivudine has a more potent and sustained antiviral activity with a lower frequency of viral resistance than lamivudine. Although there are several reports concerning the safety profile of telbivudine, most adverse events are described as mild and transient in nature. Here we report two cases of telbivudine-induced myopathy in patients with chronic hepatitis B who were siblings.

Long-term treatment outcomes of clevudine in antiviral-naive patients with chronic hepatitis B

AIM: To evaluate the treatment outcomes of clevudine compared with entecavir in antiviral-naive patients with chronic hepatitis B (CHB).

METHODS: We retrospectively analyzed the clinical data of CHB patients treated with clevudine 30 mg/d and compared their clinical outcomes with patients treated with entecavir 0.5 mg/d. The biochemical response, as assessed by serum alanine aminotransferase (ALT) activity, virologic response, as assessed by serum hepatitis B virus DNA (HBV DNA) titer, serologic response, as assessed by hepatitis B e antigen (HBeAg) status, and virologic breakthrough with genotypic mutations were assessed.

RESULTS: Two-hundred and fifty-four patients [clevudine (n = 118) vs entecavir (n = 136)] were enrolled. In clevudine-treated patients, the cumulative rates of serum ALT normalization were 83.9% at week 48 and 91.5% at week 96 (80.9% and 91.2% in the entecavir group, respectively), the mean titer changes in serum HBV DNA were -6.03 and -6.55 log₁₀ copies/mL (-6.35 and -6.86 log₁₀ copies/mL, respectively, in the entecavir group), and the cumulative non-detection rates of serum HBV DNA were 72.6% and 83.1% (74.4% and 83.8%, respectively, in the entecavir group). These results were similar to those of entecavir-treated patients. The cumulative rates of HBeAg seroconversion were 21.8% at week 48 and 25.0% at week 96 in patients treated with clevudine, which was similar to patients treated with entecavir (22.8% and 27.7%, respectively). The virologic breakthrough in the clevudine group occurred in 9 (7.6%) patients at weeks 48 and 15 (12.7%) patients at week 96, which primarily corresponded to genotypic mutations of rtM204I and/or rtL180M. There was no virologic breakthrough in the entecavir group.

CONCLUSION: In antiviral-naive CHB patients, long-term treatment outcomes of clevudine were not inferior to those of entecavir, except for virologic breakthrough.

Clinical impacts of hazardous alcohol use and obesity on the outcome of entecavir therapy in treatment-naïve patients with chronic hepatitis B infection

Background/Aims

The aim of this study was to analyze the clinical impacts of obesity and hazardous alcohol use on the outcome of entecavir (ETV) therapy in chronic hepatitis B (CHB) patients.

Methods

The medical records of 88 treatment-naïve patients who were diagnosed with CHB and received ETV between March 2007 and September 2009 were analyzed retrospectively. Body mass index (BMI) values and Alcohol Use Disorders Identification Test (AUDIT) scores were obtained at 6 months after the initiation of ETV (0.5 mg daily) treatment.

Results

A BMI of 25 kg/m² or more was recognized as an indicator of obesity, and a total AUDIT score of 8 or more was recognized as an indicator of hazardous alcohol use. Of the cohort, 24 patients (27.3%) were obese and 17 (19.3%) were hazardous alcohol users. The rate of seroconversion, alanine aminotransferase (ALT) normalization, and hepatitis B virus (HBV)-DNA negativity (<300 copies/mL) at 3, 6, and 12 months of treatment did not differ significantly between the normal-BMI and high-BMI groups. Moreover, the rate of seroconversion and HBV-DNA negativity at 3, 6, and 12 months of treatment did not differ significantly between the nonhazardous and hazardous alcohol users. However, the frequency of ALT normalization at 12 months was significantly lower among hazardous alcohol users (91.5% vs. 70.6%; P=0.033).

Conclusions

Obesity and hazardous alcohol drinking have no significant impact on the outcome of ETV treatment. However, the ALT normalization rate at 12 months after initiation of ETV treatment was significantly lower among the hazardous alcohol users.

High-dose clevudine impairs mitochondrial function and glucose-stimulated insulin secretion in INS-1E cells

Background

Clevudine is a nucleoside analog reverse transcriptase inhibitor that exhibits potent antiviral activity against hepatitis B virus (HBV) without serious side effects. However, mitochondrial myopathy has been observed in patients with chronic HBV infection taking clevudine. Moreover, the development of diabetes was recently reported in patients receiving long-term treatment with clevudine. In this study, we investigated the effects of clevudine on mitochondrial function and insulin release in a rat clonal β-cell line, INS-1E.

Methods

The mitochondrial DNA (mtDNA) copy number and the mRNA levels were measured by using quantitative PCR. MTT analysis, ATP/lactate measurements, and insulin assay were performed.

Results

Both INS-1E cells and HepG2 cells, which originated from human hepatoma, showed dose-dependent decreases in mtDNA copy number and cytochrome c oxidase-1 (Cox-1) mRNA level following culture with clevudine (10 μM-1 mM) for 4 weeks. INS-1E cells treated with clevudine had reduced total mitochondrial activities, lower cytosolic ATP contents, enhanced lactate production, and more lipid accumulation. Insulin release in response to glucose application was markedly decreased in clevudine-treated INS-1E cells, which might be a consequence of mitochondrial dysfunction.

Conclusions

Our data suggest that high-dose treatment with clevudine induces mitochondrial defects associated with mtDNA depletion and impairs glucose-stimulated insulin secretion in insulin-releasing cells. These findings partly explain the development of diabetes in patients receiving clevudine who might have a high susceptibility to mitochondrial toxicity.

Comparison of clevudine and entecavir for treatment-naive patients with chronic hepatitis B virus infection: two-year follow-up data

BACKGROUND/AIM

Clevudine and entecavir are highly potent antiviral agents being used in treatment of chronic hepatitis B. However, no data comparing clinical efficacy and safety of these 2 drugs over a long-term period is available. The aims of this study are to compare virologic, biochemical, and serologic response rates of clevudine and entecavir, as well as treatment failure rates up to 2 years.

METHODS

Data of patients who started clevudine (n = 86) or entecavir (n = 159) as a primary treatment for chronic hepatitis B at Korea University Ansan or Guro Hospital between January 2007 and June 2008 were analyzed.

RESULTS

Treatment responses were compared at 3-month intervals up to 24 months. Per protocol analysis showed no difference in virologic responses between the 2 groups at all time points, except at 18 months. When analyzed on intention-to-treat basis for virologic response at 24 months, the response rates were 45.3% in the clevudine group and 72.3% in the entecavir group, which are significantly different (P < 0.001). Rates of biochemical response and HBeAg seroconversion were not significantly different between the groups at all time points. Up to 24 months, antiviral resistance developed in 18 patients (24.4%) in the clevudine group. Clevudine was discontinued owing to muscle-related problems in 10 patients (11.6%).

CONCLUSIONS

Although both drugs showed potent antiviral activity, entecavir showed better virologic response at 24 months, primarily owing to treatment failures in the clevudine group that were associated with development of drug resistance and muscle-related problems.

Current Nucleos(t)ide Analogue Therapy for Chronic Hepatitis B

Although the prevalence of chronic hepatitis B has decreased considerably in recent years due to widespread use of the hepatitis B virus (HBV) vaccine, its prevalence still remains high in adults, and this can place a significant burden on health care in areas with endemic HBV. Since the introduction of nucleos(t)ide analogues (NUCs), there has been marked improvement in the care of patients with chronic hepatitis B, resulting in increased survival. However, the emergence of drug resistance in patients treated with NUCs is a major concern. The number of multi-drug resistant patients is increasing, and many patients may not respond to the currently available drugs. In this review, we describe the current status of NUC therapy for antiviral-naïve and -resistant patients.

A comparison of 48-week treatment efficacy between clevudine and entecavir in treatment-naïve patients with chronic hepatitis B

PURPOSE

Clevudine and entecavir are currently available in Korea as antiviral drugs against chronic hepatitis B (CHB). We aimed to compare the efficacy of clevudine and entecavir therapy.

METHODS

Treatment-naïve CHB patients who received 30 mg of clevudine or 0.5 mg of entecavir a day were analyzed. Mean reduction of hepatitis B virus (HBV) DNA levels, complete virological response (cVR, undetectable HBV DNA by real-time PCR), biochemical response (recovery to normal ALT level), and hepatitis B e antigen (HBeAg) seroconversion rate at the 48th week of treatment were assessed.

RESULTS

A number of 59 patients in clevudine group and 61 patients in entecavir group were included. Mean HBV DNA reductions from baseline were similar in the clevudine and entecavir groups, -6.4 versus -6.8 log(10) copies/mL in HBeAg-positive (p = 0.417) and -6.9 versus -7.0 log(10) copies/mL in HBeAg-negative patients (p = 0.640). The proportion of patients who achieved cVR was not different between the two groups, 53 versus 55% in HBeAg-positive (p = 1.000) and 100 versus 95% in HBeAg-negative patients (p = 0.452). Biochemical response rates and HBeAg seroconversion rates were also similar in both the groups. Two (3.4%) patients in clevudine group showed virologic breakthrough with rtM204I mutation using direct sequencing analysis. Clinical myopathy occurred in two (3.4%) patients in clevudine group.

CONCLUSION

Mean reduction of viral loads was similar between clevudine and entecavir groups during 48 weeks. However, virologic breakthrough and significant myopathy were noted only in clevudine-treated patients. Therefore, more attention should be paid to patients receiving clevudine.

Entecavir: a review of its use in chronic hepatitis B

Entecavir (Baraclude), a nucleoside analogue, is rapidly phosphorylated to the active intracellular 5'-triphosphate form that inhibits replication of hepatitis B virus (HBV). Oral entecavir is approved in the US, EU and several countries worldwide for the treatment of chronic HBV infection in adults (> or =16 years of age) with evidence of active viral replication and persistently elevated serum ALT and/or AST levels, and/or histological evidence of active disease. In several randomized, double-blind, multicentre trials, oral entecavir was an effective and generally well tolerated treatment in nucleoside-naive and lamivudine-refractory adult patients with chronic HBV infection, irrespective of whether patients were hepatitis B e antigen (HBeAg)-positive or -negative. Furthermore, it was more efficacious, associated with a lower risk of resistance, and more cost effective than lamivudine in these patient populations, with both drugs having a similar tolerability profile. In the EARLY trial, entecavir was significantly more effective than and as well tolerated as adefovir dipivoxil therapy in nucleoside-naive patients. In addition, in a double-blind, multicentre trial, entecavir plus lamivudine-based highly active antiretroviral therapy (HAART) was more effective than placebo plus lamivudine-based HAART in patients co-infected with HBV and HIV. Although the exact position of entecavir relative to other agents, such as tenofovir disoproxil fumarate and adefovir dipivoxil, for the treatment of chronic HBV infection remains to be fully determined, an important aspect in this positioning is the emergence of drug resistance. Hence, entecavir therapy provides a valuable first-line option in nucleoside-naive patients with chronic HBV infection and is a useful alternative in lamivudine-refractory patients.