A comparison of efficacy and safety of 2-year telbivudine and entecavir treatment in patients with chronic hepatitis B: a match-control study

Effect of entecavir and tenofovir disoproxil fumarate on hepatocellular carcinoma in subjects with chronic hepatitis B: a meta-analysis

Background

A meta-analysis was made to assess the impact of entecavir comparison with tenofovir disoproxil fumarate as nucleos(t)ide analogue on hepatic cellular carcinoma (HCC). The study had subjects with chronic hepatitis B virus (HBV). Systemic research was done for all studies concerned with our topic till the date (March 2022). We included 19 studies in which 27,618 subjects participated. All subjects included were diagnosed with chronic HBV at the beginning of the study. A total of 15,734 subjects from the overall 27,618 were medicated with entecavir; however, 11,884 subjects were on tenofovir disoproxil fumarate. We calculated the odds ratio (OR) with confidence intervals (CIs) of 95% to evaluate the impact of entecavir and tenofovir disoproxil fumarate on HCC in subjects with chronic HBV by applying a dichotomous approach with a random or fixed-effect model.

Results

Chronic HBV subjects treated with entecavir showed a higher significant biochemical response than those treated with tenofovir disoproxil fumarate (OR 1.39; 95% CI 1.21–1.60, at p < 0.001). Also, no significant difference was detected with entecavir compared to tenofovir disoproxil fumarate concerning the occurrence of hepatic cells cancer (OR 1.26; 95% CI 0.96–1.67, p = 0.10), virological response (OR 0.89; 95% CI 0.63–1.25, p = 0.49), and seroconversion (OR 1.27; 95% CI 0.76–2.14, p = 0.37).

Conclusions

The use of entecavir resulted in a significantly higher biochemical response; nevertheless, it did not show any significant variation concerning the occurrence of hepatic cancer, virological response, or serological conversion compared to tenofovir disoproxil fumarate in chronic HBV subjects. So, results interpretation needs to be carried out carefully owing to the limited number of studies included in specific comparisons, e.g., serological conversion.

Nucleos(t)ide analogues and Hepatitis B virus-related hepatocellular carcinoma: A literature review

Hepatitis B virus is mainly considered to cause hepatocellular carcinoma which is the fourth leading cause of cancer-related mortality worldwide. Treatment of Hepatitis B virus with nucleos(t)ide analogues can decrease the progression of the disease and subsequently decreases the incidence of hepatocellular carcinoma. In this review, we have discussed the different classes of nucleos(t)ide analogues used in the treatment of Hepatitis B virus and their relationship with the development of hepatocellular carcinoma. Furthermore, we discussed the effect of treatment of Hepatitis B virus with Nucleoside analogues (NAs) before, during and after surgery, chemoembolization, radiofrequency ablation, and chemotherapy for the treatment of hepatocellular carcinoma.

Recent Advances in Hepatitis B Treatment

Hepatitis B virus infection affects over 250 million chronic carriers, causing more than 800,000 deaths annually, although a safe and effective vaccine is available. Currently used antiviral agents, pegylated interferon and nucleos(t)ide analogues, have major drawbacks and fail to completely eradicate the virus from infected cells. Thus, achieving a "functional cure" of the infection remains a real challenge. Recent findings concerning the viral replication cycle have led to development of novel therapeutic approaches including viral entry inhibitors, epigenetic control of cccDNA, immune modulators, RNA interference techniques, ribonuclease H inhibitors, and capsid assembly modulators. Promising preclinical results have been obtained, and the leading molecules under development have entered clinical evaluation. This review summarizes the key steps of the HBV life cycle, examines the currently approved anti-HBV drugs, and analyzes novel HBV treatment regimens.

Nucleos(t)ide Analogues for Reducing Hepatocellular Carcinoma in Chronic Hepatitis B Patients: A Systematic Review and Meta-Analysis

Background/Aims

Studies have shown that nucleos(t)ide analogue (NA) treatment can reduce the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients, but it is unclear which NA is most effective. We performed a meta-analysis and systematic review comparing the efficacies of NAs in CHB patients.

Methods

We searched literature databases for randomized controlled trials (RCTs) and observational studies that analyzed the hepatic biochemical response, virological response, seroconversion rate, drug resistance rate, and HCC incidence rate in CHB patients treated with NAs. Meta-analyses were performed with RevMan and Stata/SE software.

Results

Twelve cohort studies and one RCT were selected, in which entecavir (ETV), lamivudine (LAM), telbivudine (LdT), and/or tenofovir disoproxil fumarate (TDF) were evaluated in CHB patients. The meta-analysis showed that ETV was superior to LAM with regard to the HCC incidence (p<0.001), biochemical response (p=0.001), virological response (p=0.02), and drug resistance (p<0.001), and ETV was superior to LdT with regard to the virological response (p<0.001) and drug resistance (p<0.001). We found no significant difference between ETV and TDF with regard to the HCC incidence (p=0.08), biochemical response (p=0.39), virological response (p=0.31), serological conversion (p=0.38), or drug resistance (p=0.95). NA-treated patients with pre-existing cirrhosis had a 5.49 times greater incidence of HCC than those without cirrhosis (p<0.001).

Conclusions

ETV or TDF should be used for long-term first-line monotherapy in CHB patients according to the current guidelines. Standardized protocols are needed for future studies of ETV and TDF to facilitate conclusive comparisons. Patients with cirrhosis are at significantly elevated risk for HCC, despite the benefits of NA treatment.

Nucleos(t)ide Analogues for Reducing Hepatocellular Carcinoma in Chronic Hepatitis B Patients: A Systematic Review and Meta-Analysis

Background/Aims

Studies have shown that nucleos(t)ide analogue (NA) treatment can reduce the risk of hepatocellular carcinoma (HCC) in chronic hepatitis B (CHB) patients, but it is unclear which NA is most effective. We performed a meta-analysis and systematic review comparing the efficacies of NAs in CHB patients.

Methods

We searched literature databases for randomized controlled trials (RCTs) and observational studies that analyzed the hepatic biochemical response, virological response, seroconversion rate, drug resistance rate, and HCC incidence rate in CHB patients treated with NAs. Meta-analyses were performed with RevMan and Stata/SE software.

Results

Twelve cohort studies and one RCT were selected, in which entecavir (ETV), lamivudine (LAM), telbivudine (LdT), and/or tenofovir disoproxil fumarate (TDF) were evaluated in CHB patients. The meta-analysis showed that ETV was superior to LAM with regard to the HCC incidence (p<0.001), biochemical response (p=0.001), virological response (p=0.02), and drug resistance (p<0.001), and ETV was superior to LdT with regard to the virological response (p<0.001) and drug resistance (p<0.001). We found no significant difference between ETV and TDF with regard to the HCC incidence (p=0.08), biochemical response (p=0.39), virological response (p=0.31), serological conversion (p=0.38), or drug resistance (p=0.95). NA-treated patients with pre-existing cirrhosis had a 5.49 times greater incidence of HCC than those without cirrhosis (p<0.001).

Conclusions

ETV or TDF should be used for long-term first-line monotherapy in CHB patients according to the current guidelines. Standardized protocols are needed for future studies of ETV and TDF to facilitate conclusive comparisons. Patients with cirrhosis are at significantly elevated risk for HCC, despite the benefits of NA treatment.

Efficacy and safety of long-term therapy with nucleos(t)ide analogues in chronic hepatitis B

AIM

To assess the efficacy and safety of long-term treatment with nucleos(t)ide analogues in patients with chronic hepatitis B.

MATERIALS AND METHODS

We conducted an observational study in 101 chronic hepatitis B (HBeAg-negative and HBeAg-positive) patients treated (≥3 years) with entecavir, tenofovir or telbivudine.

RESULTS

Treatment with entecavir and tenofovir was associated with high rate of virologic and biochemical response (&gt;95%) and HBeAg seroconversion (93% and 67%, respectively). Cumulative rate of virologic resistance was 0; 3.1% and 43.5% for tenofovir, entecavir and telbivudine, respectively. Long-term nucleos(t)ide analogues treatment resulted in a regress of liver fibrosis (from 8.92 to 7.18 kPa, р&lt;0.0001) and reduction in the number of patients with advanced fibrosis (from 48.1% to 13.8%, р&lt;0.0001). Entecavir and tenofovir were safe and well tolerated, while treatment with telbivudine was associated with development of myopathy in 13% of cases.

CONCLUSION

Entecavir and tenofovir might be recommended for the treatment of chronic hepatitis B because of having potent antiviral effect, high genetic barriers against resistance and good safety.

Taiwan consensus statement on the management of chronic hepatitis B

The experts of Taiwan Association for the Study of Liver (TASL) have actively participated and led the guidelines on hepatitis B virus (HBV) management by Asian Pacific Association for the Study of Liver (APASL) which is the first international association for the study of liver to publish the statement on HBV management before. However, there are more and more new data on the natural history and treatment of HBV infection in the past decade. These include new application of an old biomarker (quantitative HBsAg), clinical significance of HBV genotype and naturally occurring mutations, the role of non-invasive examination in evaluating severity of hepatic fibrosis, clinical significance of outcome calculators, new drug or new combination strategies towards more effective therapy and organ transplantation including liver and non-liver transplantation. It is time to publish the guidelines on HBV management of Taiwan. Hence, TASL have conducted an expert meeting to review, to discuss and to debate the relevant literatures, followed by draft the manuscript of HBV management guidelines and recommendations. The guidelines include general management, indications for fibrosis assessment, time to start or stop drug therapy, choice of drug to initiate therapy, when and how to monitor the patients during and after stopping drug therapy. Recommendations on the therapy of patients in special circumstances, including women in childbearing age, patients with antiviral drug resistance, concurrent viral infection, hepatic decompensation, patient receiving immune suppression or chemotherapy and patients in the setting of liver transplantation and hepatocellular carcinoma, are also included.

Telbivudine attenuates UUO-induced renal fibrosis via TGF-β/Smad and NF-κB signaling

Renal fibrosis yields decreased renal function and is a potent contributor to chronic kidney disease (CKD). Telbivudine (LdT) is an anti-hepatitis B virus (HBV) drug that has been found to steadily improve renal function, but the mechanism of drug action is unclear. One explanation is that LdT impacts inflammatory or fibrotic pathways. In this study, we investigated renal protection by LdT in a rat model of unilateral ureteral obstruction (UUO). UUO rats received oral gavage of LdT (1, 1.5, or 2g/kg/day) for 5weeks. Kidney tissues were examined histopathologically with hematoxylin and eosin and Masson's trichrome stain. To assess proliferation of myofibroblasts and matrix accumulation, α-smooth muscle actin (α-sma) and collagen type I and III were detected. Interleukin-1 (IL-1) and tumor necrosis factor (TNF)-α were evaluated as a measure of proinflammatory cytokines. Transforming growth factor (TGF)-β and nuclear factor-κB (NF-κB) were considered the canonical signaling components in our investigation of the underlying mechanism of LdT action. Histopathology results indicated that LdT ameliorates renal injury and matrix accumulation. Expression of α-sma and collagen I/III as well as key fibrotic signaling factors in the TGF-β/Smad pathway were downregulated. In addition, LdT suppressed the release of IL-1 and TNF-α and decreased the expression of NF-κB by inhibiting toll-like receptor 4. Taken together, these findings indicate that LdT can attenuate renal fibrosis and inflammation via TGF-β/Smad and NF-κB pathways in UUO.

Long-term outcome of telbivudine versus entecavir in treating higher viral load chronic hepatitis B patients without cirrhosis

Chronic hepatitis B (CHB) patients with higher hepatitis B virus (HBV) load (higher viral load [HVL], HBV DNA ≥1 × 10⁷ copies/mL) require antiviral therapy, but data for evaluating the long-term outcome of this therapy with antiviral agents remain limited. We comparatively evaluated the efficacy and the safety of nucleoside analogues in 179 noncirrhotic CHB patients with HVL over 5 years. The HBeAg-positive (n = 104) or HBeAg-negative (n = 75) patients were treated consecutively with telbivudine (LdT, n = 88) or entecavir (ETV, n = 91) and evaluated for viral response, drug resistance and safety. HBV DNA, viral serology, biochemistries, HBV mutation and off-therapy relapse were determined. The cumulative rates of HBV DNA negativity were 86.4% and 94.5% for LdT and ETV at year 5, respectively. The rates of early viral response (EVR, HBV DNA <10³ copies/mL at month 6) under LdT and ETV treatments were 58.0% and 34.1%, respectively (P < .05). Hepatitis B e antigen (HBeAg) and Hepatitis B surface antigen (HBsAg) loss-seroconversions were 47.7% and 18.2% on LdT and 16.5% and 2.2% on ETV (P < .01). Eighteen patients (age 28.2 ± 3.1) experienced HBsAg loss-seroconversion, followed by 33 ± 4.6 month off-therapy without a relapse. Viral mutations and serum creatine kinase elevation were 9.1% and 8.0% on LdT, but only 1.1% and 0% on ETV. Both LdT and ETV suppressed HBV replication in HVL CHB patients within 5 years. LdT therapy achieved a higher EVR, HBeAg and HBsAg seroconversion, especially in the younger patients, whereas ETV caused lower drug resistance and fewer adverse events. This finding might help to identify the optimal treatment for CHB patients with HVL.

Telbivudine attenuates gentamicin-induced kidney injury in rats

Nephrotoxicity has been associated with nucleos(t)ide analogues other than telbivudine (LdT). This study investigated the potential effects of LdT and lamivudine (LAM) on renal function in an experimental rat model of gentamicin-induced acute nephrotoxicity. A total of 28 healthy Wistar albino rats were randomly divided into four experimental groups: negative control; positive control (PC); LdT; and LAM. Nephrotoxicity was induced by gentamicin in the LdT, LAM and PC groups. LdT and LAM were administered to two groups for 6 weeks starting on the ninth day. Blood samples were collected weekly and cystatin C levels were measured by ELISA. Animals were sacrificed on the 50th day and the kidneys were removed for histological examination. Serum cystatin C levels differed significantly between the LdT and LAM groups (P <0.007) and between the LdT and PC groups (P <0.001). Renal function was significantly improved in the LdT group at the start of antiviral treatment on Day 8 and at the end of treatment on Day 50 (P = 0.001 and 0.007). Glomerular injury, acute tubular necrosis and total injury score were significantly reduced in the LdT group relative to the PC and LAM groups upon histopathological examination. LdT was associated with significant improvements in renal function as measured by biochemical and histopathological methods. The acute kidney injury model data should be supported by clinical studies to suggest that LdT treatment may have advantages for patients with underlying chronic kidney disease receiving chronic hepatitis B treatment.

Adverse effects of oral antiviral therapy in chronic hepatitis B

Oral nucleoside/nucleotide analogues (NAs) are currently the backbone of chronic hepatitis B (CHB) infection treatment. They are generally well-tolerated by patients and safe to use. To date, a significant number of patients have been treated with NAs. Safety data has accumulated over the years. The aim of this article is to review and update the adverse effects of oral NAs. NAs can cause class adverse effects (i.e., myopathy, neuropathy, lactic acidosis) and dissimilar adverse effects. All NAs carry a “Black Box” warning because of the potential risk for mitochondrial dysfunction. However, these adverse effects are rarely reported. The majority of cases are associated with lamivudine and telbivudine. Adefovir can lead to dose- and time-dependent nephrotoxicity, even at low doses. Tenofovir has significant renal and bone toxicity in patients with human immunodeficiency virus (HIV) infection. However, bone and renal toxicity in patients with CHB are not as prominent as in HIV infection. Entecavir and lamivudine are not generally associated with renal adverse events. Entecavir has been claimed to increase the risk of lactic acidosis in decompensated liver disease and high Model for End-Stage Liver Disease scores. However, current studies reported that entecavir could be safely used in decompensated cirrhosis. An increase in fetal adverse events has not been reported with lamivudine, telbivudine and tenofovir use in pregnant women, while there is no adequate data regarding entecavir and adefovir. Further long-term experience is required to highlight the adverse effects of NAs, especially in special patient populations, including pregnant women, elderly and patients with renal impairment.

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.

Telbivudine vs tenofovir in hepatitis B e antigen-negative chronic hepatitis B patients: OPTIMA roadmap study

AIM

To make efficacy and safety comparison of telbivudine-raodmap and tenofovir-roadmap in hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB) patients.

METHODS

This was the first prospective, randomised, two-arm, open-label, non-inferiority study in HBeAg-negative CHB patients that compared telbivudine and tenofovir administered as per roadmap concept. Patients were treated up to 24 wk and, depending on virologic response, continued the same therapy or received add-on therapy up to 104 wk. Eligible patients received an additional 52 wk of treatment in the extension period (i.e., up to 156 wk). Patients who developed virologic breakthrough (VB) while on monotherapy also received add-on therapy. The primary efficacy endpoint was the rate of patients achieving hepatitis B virus (HBV) DNA < 300 copies/mL at week 52. Secondary efficacy endpoints included the rates of HBV DNA < 300 and < 169 copies/mL, HBV DNA change from baseline, alanine aminotransferase normalisation, hepatitis B surface antigen (HBsAg) loss, HBsAg seroconversion, VB, and emergence of resistance at various timepoints throughout the study. Safety and estimated glomerular filtration rate (eGFR) were also analysed.

RESULTS

A total of 241 patients were randomised. Non-inferiority of telbivudine arm to tenofovir arm was demonstrated at week 52 (± 7 d window), with over 91% of patients in each treatment arm achieving HBV DNA level < 300 copies/mL. Both arms were similar in terms of key secondary efficacy variables at weeks 104 and 156. The percentage of patients achieving HBV DNA < 300 copies/mL remained high and was similar in the telbivudine and tenofovir arms at both weeks 104 and 156. Over 82% of patients in both arms achieved alanine aminotransferase normalisation at week 52, and this percentage remained high at weeks 104 and 156. Telbivudine treatment progressively reduced serum HBsAg levels from baseline while no change was reported in quantitative HBsAg during therapy with tenofovir. Both treaments showed acceptable safety profiles. The telbivudine arm showed eGFR improvement unlike the tenofovir arm.

CONCLUSION

Efficacy was shown for both telbivudine-roadmap and tenofovir-roadmap regimens in HBeAg-negative CHB patients over 156 wk. Telbivudine arm was associated with renal improvement.

Comparison of the Efficacies and Safety of Combined Therapy between Telbivudine Plus Adefovir and Lamivudine Plus Adefovir in Patients with Hepatitis B Virus Infection in Real-World Practice

Background and Aim

Chronic hepatitis B infection remains a significant health issue worldwide. This study evaluated the efficacy and safety of combined therapy using lamivudine plus adefovir (LAM+ADV) versus telbivudine plus adefovir (LdT+ADV) and the corresponding renal function change and safety.

Methods

This study enrolled a total of 171 patients (110 patients received LAM+ADV and 60 patients received LdT+ADV). We analyzed the changes in renal function using the estimated glomerular filtration rate (eGFR). The DNA undetectable rate, hepatitis B e antigen (HBeAg) seroconversion rate, and alanine aminotransferase (ALT) normalization rate were analyzed. We checked the serum uric acid, phosphate and creatine kinase, and lactic acid levels to analyze safety. We observed these patients for 48 to 240 weeks and checked their serum profile every 6 months.

Results

There was no statistically significant difference between the two groups in anti-hepatitis B virus (HBV) efficacy in terms of DNA undetectable rate, ALT normalization rate, and HBeAg seroconversion rate. Both the LAM+ADV and LdT+ADV groups had stable or improved renal function. However, a higher eGFR was found in the LdT+ADV group with continuous serum fluctuation during 3 years of combined therapy as well as a higher serum creatine kinase level.

Conclusions

Long-term LdT+ADV combined therapy and LAM+ADV combined therapy were both associated with stable or improved renal function. The clinical efficacy was similar between the two groups, but the LdT group had a higher serum creatine kinase level. We need to monitor the data regularly in clinical practice.

Editor's Highlight: Comparative Renal Safety Assessment of the Hepatitis B Drugs, Adefovir, Tenofovir, Telbivudine and Entecavir in Rats

The aim of this study was to determine the relative safety of 4 antiviral drugs (telbivudine, tenofovir, adefovir, and entecavir) against hepatitis B virus with respect to kidney function and toxicity in male Sprague Dawley rats. The antiviral drugs were administered once daily for 4 weeks by oral gavage at ∼10 and 25-40 times the human equivalent dose. Main assessments included markers of renal toxicity in urine, magnetic resonance imaging (MRI) of kidney function, histopathology, and electron microscopic examination. Administration of adefovir at 11 and 28 mg/kg for 4 weeks caused functional and morphological kidney alterations in a time- and dose-dependent manner, affecting mainly the proximal tubules and suggesting a mechanism of toxicity related to mitochondrial degeneration/depletion. Of note, the observed adefovir-induced reduction of kidney function was not detected by the standard method of glomerular filtration rate (GFR) measurements (clearance rate of the endogenous marker, creatinine), thereby emphasizing the superiority of MRI in terms of sensitive detection of GFR in rats. For the low dose of 300 mg/kg of tenofovir, minor kidney effects such as nuclear enlargement in the tubular epithelium, and hyaline droplets accumulation were detected, which was also observed for the low dose (11 mg/kg) of adefovir. No assessments could be done at the higher dose of 600/1000 mg/kg tenofovir due to gastrointestinal tract toxicity which prevented treatment of the animals for longer than 1 week. Entecavir at 1 and 3 mg/kg and telbivudine at 600 and 1600 mg/kg caused no toxicologically relevant effects on the kidney.

The assessment of hepatocellular carcinoma risk in patients with chronic hepatitis B under antiviral therapy

Hepatocellular carcinoma (HCC) is a primary concern for patients with chronic hepatitis B (CHB). Antiviral therapy has been reasonably the focus of interest for HCC prevention, with most studies reporting on the role of the chronologically preceding agents, interferon-alfa and lamivudine. The impact of interferon-alfa on the incidence of HCC is clearer in Asian patients and those with compensated cirrhosis, as several meta-analyses have consistently shown HCC risk reduction, compared to untreated patients. Nucleos(t)ide analogues also seem to have a favorable impact on the HCC incidence when data from randomized or matched controlled studies are considered. Given that the high-genetic barrier agents, entecavir and tenofovir, are mainly used in CHB because of their favorable effects on the overall long-term outcome of such patients, the most clinically important challenge is the identification of patients who require close HCC surveillance despite on-therapy virological remission. Several risk scores have been developed for HCC prediction in CHB patients. Most of them, such as GAG-HCC, CU-HCC and REACH-B, have been developed and validated in Asian untreated and treated CHB patients, but they do not seem to offer good predictability in Caucasian CHB patients for whom a newer score, PAGE-B, has been recently developed.

Renal Function in Nucleos(t)ide Analog-Treated Patients With Chronic Hepatitis B: A Systematic Literature Review and Network Meta-Analysis

INTRODUCTION

Renal safety is an important factor in selecting the most appropriate nucleos(t)ide analog (NA) treatment for patients with chronic hepatitis B (CHB). This systematic literature review and network meta-analysis aimed to assess renal function associated with telbivudine treatment compared to other NAs in patients with CHB.

METHODS

A systematic literature search via Medline, Medline In-Process, Embase, and the Cochrane library for publications of randomized controlled trials and observational studies was conducted. Network meta-analysis was performed to compare renal function with telbivudine treatment versus other NAs after 1 year of therapy.

RESULTS

Overall, 40 (six randomized controlled and 34 observational) studies were included for review. Telbivudine consistently showed an improvement in renal function as measured by an estimated glomerular filtration rate (eGFR) over various time points regardless of the method of measurement. Changes in eGFR (mL/min) from baseline and corresponding 95% credible intervals with various NAs were as follows: monotherapies (telbivudine: 7.78 [6.91, 8.65], entecavir: -1.07 [-4.80, 2.62], lamivudine: -6.08 [-13.35, 1.15], tenofovir: -9.53 [-14.31, -4.89]) and combination therapies (telbivudine + adefovir: 8.37 [-34.00, 50.34], telbivudine + tenofovir: 8.29 [-0.05, 16.64], entecavir + adefovir: 4.15 [-38.55, 46.37], telbivudine + lamivudine: 0.51 [-11.77, 12.96], and lamivudine + adefovir: -0.39 [-42.48, 41.21]). At 1 year, the change in eGFR from baseline was significantly higher with telbivudine compared to other NAs.

CONCLUSION

The systematic literature review and network meta-analysis provide evidence that telbivudine is associated with significant improvement in renal function in patients with CHB, either alone or in combination with other NAs.

FUNDING

Novartis Pharma AG.

Comparison of clinical efficacy and renal safety of telbivudine and entecavir in chronic hepatitis B patients receiving cytotoxic chemotherapy

OBJECTIVE

Limited data is available on the clinical outcomes of telbivudine (LdT) and entecavir (ETV) in pre-emptive antiviral chemoprophylaxis. This study aimed to evaluate the clinical efficacy and renal safety of LdT and ETV in patients with chronic hepatitis B (CHB) who received cytotoxic chemotherapy.

METHODS

Altogether 290 treatment-naïve CHB patients undergoing intense chemotherapy were enrolled to receive daily 600 mg of LdT or 0.5 mg of ETV as pre-emptive antiviral chemoprophylaxis.

RESULTS

The ETV group had significantly higher proportion of patients with undetectable hepatitis B viral (HBV) DNA load compared with LdT at week 24 (73.0% vs 50.3%, P = 0.000). The cumulative rates of virological breakthrough in the LdT and ETV groups were 9.15% and 3.65% at the second year of therapy, respectively (P = 0.059), which was associated with detectable HBV DNA at week 24 (P = 0.000). The MELD score of the LdT group was significantly lower than that of the ETV group after the first year (4.53 vs 7.53, P = 0.002) and the second year (1.96 vs 7.09, P = 0.000) of antiviral therapy. Moreover, the estimated glomerular filtration rate (eGFR) was significantly improved in the LdT group than in the ETV group after two years of antiviral therapy.

CONCLUSION

LdT has a lower clinical efficacy in viral suppression than ETV, but LdT is associated with greater extent of improvement in liver and renal functions of patients in pre-emptive prophylaxis for cytotoxic chemotherapy.

Potential effects of telbivudine and entecavir on renal function: a systematic review and meta-analysis

Background

To assess the potential effects of telbivudine (LdT) and entecavir (ETV) on renal function in patients with chronic hepatitis B (CHB), we performed a meta-analysis of the relevant data available on these agents to evaluate their effects on the estimated glomerular filtration rate (eGFR) during treatment.

Methods

The PubMed, EMBASE, Scopus, CNKI (China National Knowledge Infrastructure), Cochrane Library, and WanFang databases were searched for relevant articles appearing in the literature up to July 1, 2015. A total of 6 studies (1960 CHB patients) with 1-year eGFR outcomes were retrieved and analyzed.

Results

Generally, the results of the 6 studies analyzed showed that eGFR was improved after LdT treatment, but was decreased after ETV treatment. Using a fixed-effects approach, the change in eGFR was found to be significantly different between LdT and ETV treatment (Z = 3.64; P = 0.0003). Whereas the eGFR was slightly decreased with ETV compared with baseline (−1.45 mL/min/1.73 m²), the eGFR was improved with LdT (2.99 mL/min/1.73 m²) after 1 year of treatment. An overall test of effect in the meta-analysis showed that the eGFR in LdT-treated patients was significantly improved after 1-year of treatment (Z = 3.71; P = 0.0002).

Conclusion

This meta-analysis has confirmed that LdT has a renal protective effect whereas ETV does not. However, whether the benefit on renal function outweighs the occurrence of resistance in specific clinical situations is not yet clear.

Does Nucleos(t)ide Analogues Treatment Affect Renal Function in Chronic Hepatitis B Patients Who Have Already Decreased eGFR? A Longitudinal Study

This study aimed to assess the renal function in chronic hepatitis B (CHB) patients who received nucleos(t)ide analogues (NAs) therapy using estimated glomerular filtration rate (eGFR) titer. We performed a longitudinal observational study of 37 tenofovir-, 42 telbivudine-, and 62 entecavir-naïve CHB patients, who had impaired renal function (eGFR, 90-30 ml/min/1.73m2) without history of diabetes, hypertension, and chemotherapy. Calculation and evaluation of eGFR was performed with the Modification of Diet in Renal Disease, Chronic Kidney Disease Epidemiology Collaboration, and Cockcroft-Gault formula at pretreatment, at baseline, and after the 1st and 2nd year of treatment. The eGFR was significantly increased in patients given telbivudine or entecavir (p = 0.003 and p = 0.012, respectively), but the eGFR was decreased in patients given tenofovir (p = 0.001) after 2 years of treatment. Of all patients, eGFR was stable one year prior to treatment. If we analyzed the renal function by change of chronic kidney disease (CKD) category with a change of 25% of eGFR, the proportion of uncertain drop (drop in CKD category with <25% decrease in eGFR) and certain drop (drop in CKD category with ≧25% decrease in eGFR) in tenofovir group was smaller (5.4%) than those of telbivudine (12.9%) or entecavir (6.5%). Furthermore, telbivudine had the lowest stable rate (76.2%), the highest certain rise rate (9.5%), and certain drop rate (7.1%) compared to the other groups (p = 0.049). In conclusion, in NAs-naïve CHB patients with impaired renal function, telbivudine and entecavir resulted in a significant increase in eGFR while tenofovir resulted in a significant decrease after a 2-year treatment. Interestingly, TDF had the lowest proportion of patients reclassified to certain and uncertain drop groups; in contrast, LdT had a higher proportion in both raise and drop groups. The outcomes of this renal effect remain to be determined.

A comparison of telbivudine and entecavir in the treatment of hepatitis B e antigen-positive patients: a prospective cohort study in China

There are few studies directly comparing the efficacy and safety of telbivudine and entecavir. The present prospective cohort study aimed to evaluate the long-term efficacy and safety of these compounds in 196 hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B for a median follow-up period of 172 weeks; 97 were treated with telbivudine and 99 were treated with entecavir. Patients showing suboptimal responses could also take adefovir at 24-48 weeks and all patients with viral breakthrough were started on adefovir. The 240-week cumulative proportions of patients showing undetectable hepatitis B DNA levels and serum alanine transaminase (ALT) normalization were similar in the two study groups. Viral breakthrough developed in 14% of the telbivudine group and in 2% of the entecavir group (p 0.002). Interestingly, the cumulative proportions of patients treated with entecavir and telbivudine showing HBeAg seroconversion were 12% versus 21% at 48 weeks (p 0.041), 15% versus 38% at 96 weeks (p 0.001), 24% versus 50% at 144 weeks (p 0.001), 33% versus 53% at 192 weeks (p 0.004) and 36% versus 53% at 240 weeks (p 0.005), respectively. Patients treated with telbivudine were therefore significantly more likely to show HBeAg seroconversion than those receiving entecavir and similar results were observed in study sub-groups matched for age, serum ALT, and HBV DNA levels. A safety analysis identified no differences between grade 3/4 creatine kinase elevations in the study groups and only telbivudine was associated with improved kidney function.

Comparison of efficacy and renal safety of telbivudine and entecavir in treatment-naive elderly patients with chronic hepatitis B

BACKGROUND

Data comparing the clinical outcomes of telbivudine (LdT) and entecavir (ETV) in elderly patients with chronic hepatitis B are limited.

GOALS

The aim of the present study was to compare the efficacy and renal safety of LdT and ETV in treatment-naive elderly (≥ 60 years) patients with chronic hepatitis B.

METHODS

A total of 33 patients treated with LdT were consecutively enrolled in the study. Each patient was matched on the basis of age, sex, and baseline hepatitis B virus (HBV) DNA levels with three to four randomly selected controls treated with ETV.

RESULTS

Clinical characteristics were comparable between the two groups. Higher cumulative HBeAg-seroconversion rates were observed in the LdT group than in the ETV group after 2 years (50 vs. 20%) and 3 years (50 vs. 26.67%) of treatment (all P<0.0001). Virological response rate at week 24 was significantly lower in the LdT group than it was in the ETV group (54.55 vs. 70.87%, P<0.0001), but no significant difference was noted in long-term cumulative rates of undetectable HBV DNA levels between the two groups (P=0.562). Virological breakthrough occurred in six (18.18%) LdT patients, with no such cases reported in the ETV group (P<0.0001). Antiviral resistance was strongly associated with LdT use and the absence of undetectable HBV DNA at weeks 12 and 24 (P<0.0001). During the study, significant improvement was observed in the estimated glomerular filtration rate and model for end-stage liver disease score in LdT versus ETV group.

CONCLUSION

LdT has a lower clinical efficacy for viral suppression and a higher risk of antiviral resistance than does ETV. However, LdT resulted in higher HBeAg-seroconversion rates and better renoprotective effects than did ETV.

Comparison of renal safety and efficacy of telbivudine, entecavir and tenofovir treatment in chronic hepatitis B patients: real world experience

This study aims to assess the nephrotoxicity and efficacy of tenofovir disoproxil fumarate (tenofovir), telbivudine and entecavir. A retrospective study of 587 patients with chronic hepatitis B treated with tenofovir (n = 170), telbivudine (n = 184) and entecavir (n = 233) for at least 1 year. Renal function and efficacy were assessed. The estimated glomerular filtration rate (eGFR) decreased significantly in the tenofovir group after a mean of 17 months treatment (from 92.2 to 85.6 mL/min/1.73 m(2), p < 0.001), but increased in the telbivudine group after a mean of 32 months of treatment (from 86.1 to 95 mL/min/1.73 m(2), p < 0.001). There was no significant change in eGFR in the entecavir group after a mean of 44 months. By multivariate analysis, pre-existing renal insufficiency (p = 0.003), tenofovir (p = 0.007) and diuretic treatment (p = 0.001) were independent predictors for renal function deterioration. Cumulative virological breakthrough was 0% in tenofovir after 2 years, 3.4% in entecavir after 7 years and 22.9% in telbivudine after 5 years. Liver cirrhosis (p = 0.008) and virological breakthrough (p = 0.040) were independently associated with increased risk of hepatocellular carcinoma development. Tenofovir may lead to deterioration in renal function as assessed by serial eGFR measurements. Although telbivudine appeared to be associated with an improvement in eGFR, it was associated with high rates of virological breakthrough, which was an independent risk factor for HCC development. With low rates of virological breakthrough and preservation of renal function, entecavir could be the best choice among these three agents.

New therapeutic perspectives in HBV: when to stop NAs

The goal of chronic hepatitis B (CHB) treatment is to achieve seroclearance of HBsAg. Nucleos(t)ide analogues (NAs) are one of the first-line treatments for CHB. NAs produce a potent suppression of viral replication but are associated with a low rate of HBsAg seroclearance and a high risk of virological relapse after discontinuation. Because of these reasons, long-term treatment is needed. They are well-tolerated oral drugs, and it seems they do not produce important side-effects in long-term administration. The duration of NA treatment remains unclear, nevertheless, in some patients NAs can be stopped with a low rate of relapse. HBeAg-positive patients could discontinue NA therapy if they achieved HBeAg seroclearance and maintain undetectable HBV DNA. For HBeAg-negative patients, to stop NA treatment is not recommended. In addition to other factors, serum HBsAg titres during treatment have recently been proposed to guide NA-based therapy duration in selected patients. All patients could be stopped from taking treatment if they achieve HBsAg loss.

Clinical utility of entecavir for chronic hepatitis B in Chinese patients

The People's Republic of China has one of the highest rates of hepatitis B virus (HBV) infection. This review summarizes recent data from studies of entecavir, one of the recommended first-line oral therapies for treating chronic hepatitis B, in Chinese HBV-infected patients. Long-term treatment with entecavir is efficacious and well tolerated, and studies comparing entecavir with other nucleos(t)ide therapies, such as lamivudine, adefovir, and telbivudine, demonstrate superior antiviral effects for entecavir therapy and comparable safety profiles. Entecavir monotherapy and combination treatment with other nucleos(t) ide analogs has been shown to be efficacious in the treatment of lamivudine-resistant and adefovir-resistant patients with HBV infection, as well as in patients with multidrug-resistant disease. Entecavir has also been shown to be effective in patients with HBV-associated clinical morbidity, including cirrhosis and liver failure, as well as in preventing recurrence of HBV following liver transplantation and in preventing reactivation of HBV after immunosuppres-sive therapy. Although the cost of anti-HBV therapy is a particular concern in the People's Republic of China, a number of studies have recently demonstrated that entecavir (particularly long-term therapy) represents a more cost-effective treatment strategy compared with other nucleos(t)ide therapies. Further research is required to assess the effects of entecavir combination therapy on hepatitis B surface antigen clearance, and in drug-resistant patients in the People's Republic of China.