Meta-analysis: adefovir dipivoxil in combination with lamivudine in patients with lamivudine-resistant hepatitis B virus

Efficacy of nucleos(t)ide analogues(NAs) in preventing virus reactivation in oncology patients with HBV infection after chemotherapy or surgery: A network meta-analysis

Objective

In this study, we aimed to perform a network meta-analysis to compare the effectiveness of NAs in decreasing the reactivation of HBV, reducing chemotherapy disruption, and improving survival in oncology patients.

Methods

Relevant randomized controlled trials (RCT) evaluating the impact of NAs in HBV infected-related oncology patients were retrieved from electronic databases. The outcome indicators included reactivation rate, survival rate of 1 to 3 years after treatment, and chemotherapy disruption rate. The studies were evaluated for bias using the RCT risk of bias assessment tool recommended in the Cochrane Handbook. The risk ratio (RR) was used to compare the outcome indicators for the anti-viral treatment, and the surface under the cumulative ranking curves (SUCRA) was used to identify the optimal therapeutic regime.

Results

A total of 67 trials containing 5722 patients were included in this study. Regarding the reduction of reactivation rate, entecavir, lamivudine, adefovir alone were less effective than the combination of lamivudine and entecavir (94.9%), with RR values ranging from 3.16 to 3.73. However, based on SUCRA, the efficacy of telbivudine (80.3%) and the combination of lamivudine and adefovir dipivoxil (58.8%) were also acceptable. Entecavir (RR values ranging from 1.25 to 1.50) and lamivudine (RR values ranging from 1.27 to 1.35) can prolong the survival rate of patients at 1-3 years, and were better than adefovir dipivoxil in the comparison of 1-year survival rate. The RR values were 1.18 and 1.19, respectively. And entecavir 's ranking in SUCRA was more stable. Entecavir, lamivudine, and tenofovir all reduced chemotherapy interruption rates compared with no antiviral therapy, especially for tenofovir.

Conclusions

Current evidence shows that lamivudine combined with entecavir, telbivudine, and lamivudine combined with adefovir dipivoxil were the most effective in preventing virus reactivation in HBV infected-related cancer patients treated with chemotherapy. Entecavir had the most stable effect on survival, while tenofovir had the best impact on reducing the chemotherapy disruption rate. Due to limited quality and quantity of the included studies, more high-quality studies are required to verify the above conclusions.

Systematic review registration

PROSPEROI [https://www.crd.york.ac.uk/PROSPERO/index.php], identifier CRD4202250685.

Quantitative HBsAg and Qualitative HBeAg Predicts Intrauterine Placental Infection and Umbilical Blood Cord in Pregnant Women

Objective: To know the correlation between quantitative Hepatitis B surface Antigen (HbsAg) and maternal Hepatitis B Envelope Antigen (HbeAg) with hepatitis B intrauterine transmission via placental infection. Hepatitis B in pregnancy causes a mother to child transmission (MTCT) via transplacental route started with placental infection. HBV DNA viral load and HBeAg are the independent risk factors for MTCT, but it rarely available in developing country.

Materials and methods: A cross-sectional study in 33 pregnant women with HbsAg positive in 4 referral hospital in East Java, Indonesia. Quantitative HBS Ag and HBeAg) status were determined serologically from a peripheral venous blood sample. Placental Hepatitis B infection was detected by immunohistochemistry of HBsAg from placental tissues. The intrauterine transmission was diagnosed by positive HBsAg in cord blood sampling after deliveries.

Results: Serum quantitative HBsAg level has a good sensitivity and spesificity to predict placental infection (90% and 83%), with a cut off value of 3.14 Log10 IU/mL (AUC 0.87; 95% CI: 0.74-0.99). Quantitative HBsAg level also has a good sensitivity and spesificity to predict HBV transmission in umbilical blood cord (81.8% and 95.5%) with a cut off value of 3.62 log₁₀ IU/ml (AUC: 0.925, 95% CI: 0.813-1; p = 0.000). Placental infection is significantly related with intrauterine transmission with OR 4.6 (95% CI 2.29-9.4; p = 0.002).

Conclusion: The study reveals that maternal serum quantitative HBsAg level can be used as an alternative test to substitute HBeAg or HBV DNA as a marker to predict the placental infection and intrauterine transmission, especially in low-middle income countries.

Coevolution analysis of amino-acids reveals diversified drug-resistance solutions in viral sequences: a case study of hepatitis B virus

The study of mutational landscapes of viral proteins is fundamental for the understanding of the mechanisms of cross-resistance to drugs and the design of effective therapeutic strategies based on several drugs. Antiviral therapy with nucleos(t)ide analogues targeting the hepatitis B virus (HBV) polymerase protein (Pol) can inhibit disease progression by suppression of HBV replication and makes it an important case study. In HBV, treatment may fail due to the emergence of drug-resistant mutants. Primary and compensatory mutations have been associated with lamivudine resistance, whereas more complex mutational patterns are responsible for resistance to other HBV antiviral drugs. So far, all known drug-resistance mutations are located in one of the four Pol domains, called reverse transcriptase. We demonstrate that sequence covariation identifies drug-resistance mutations in viral sequences. A new algorithmic strategy, BIS2TreeAnalyzer, is designed to apply the coevolution analysis method BIS2, successfully used in the past on small sets of conserved sequences, to large sets of evolutionary related sequences. When applied to HBV, BIS2TreeAnalyzer highlights diversified viral solutions by discovering thirty-seven positions coevolving with residues known to be associated with drug resistance and located on the four Pol domains. These results suggest a sequential mechanism of emergence for some mutational patterns. They reveal complex combinations of positions involved in HBV drug resistance and contribute with new information to the landscape of HBV evolutionary solutions. The computational approach is general and can be applied to other viral sequences when compensatory mutations are presumed.

Entecavir for patients with lamivudine‐resistant chronic hepatitis B virus infection

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To evaluate the benefits and harms of entecavir versus no intervention, placebo, and non‐entecavir interventions in adults with lamivudine‐resistant, chronic hepatitis B virus infection.

The Effect of Prophylactic Lamivudine plus Adefovir Therapy Compared with Lamivudine Alone in Preventing Hepatitis B Reactivation in Lymphoma Patients with High Baseline HBV DNA during Chemotherapy

Prophylactic antiviral therapy is essential for lymphoma patients with high baseline HBV DNA who undergo cytotoxic chemotherapy. However, there are limited data on the optimal options. The present study was designed to compare the efficacy of prophylactic lamivudine (LAM) with lamivudine plus adefovir dipivoxil (LAM+ADV) in preventing hepatitis B virus (HBV) reactivation in lymphoma with, pre-chemotherapy HBV DNA load ≥2000 IU/ml. We retrospectively analyzed the medical records of 86 lymphoma patients with baseline HBV DNA load ≥2000 IU/ml during chemotherapy and received LAM or LAM+ADV as prophylaxis between January 1, 2008 and November 30, 2014 at Sun Yat-sen University Cancer Center, China. Sixty-five patients received LAM and 21 received LAM+ADV. The rate was significantly lower in the LAM+ADV group compared with the LAM group for HBV reactivation (23.8% vs 55.4%; p = 0.012), while no difference was observed between the two groups in patients for HBV-related hepatitis (21.3% vs 33.3%; p   =  0.349), and chemotherapy disruption (10.9% vs 19.0%; p = 0.337). In a multivariate analysis of factors associated with HBV reactivation in these patients, LAM+ADV treatment and HBeAg negative were the independent protective factors. Therefore, LAM+ADV should be considered for antiviral prophylaxis in lymphoma patients with pre-chemotherapy HBV DNA load ≥2000 IU/ml. Further study is warranted to confirm these findings.

Comparison of the clinical outcomes between antiviral-naïve patients treated with entecavir and lamivudine-resistant patients receiving adefovir add-on lamivudine combination treatment

Background/Aims

To analyze the effects of preexisting lamivudine (LAM) resistance and applying antiviral treatment (adefovir [ADV] add-on LAM combination treatment) on long-term treatment outcomes, and comparing the clinical outcomes of antiviral-naïve chronic hepatitis B patients receiving entecavir (ETV) monotherapy.

Methods

This study enrolled 73 antiviral-naïve patients who received 0.5-mg ETV as an initial therapy and 54 patients who received ADV add-on LAM combination treatment as a rescue therapy from July 2006 to July 2010.

Results

During 24-month treatments, the decreases in serum log10HBV-DNA values (copies/mL) were significantly greater in the antiviral-naïve patients treated with ETV than the patients receiving ADV add-on LAM combination treatment. The biochemical response rates for alanine aminotransferase normalization at 6 months (ETV) and 12 months (ADV add-on LAM) were 90.4% (66/73) and 77.8% (42/54), respectively (P=0.048). A Kaplan-Meier analysis indicated that the rates of serologic response, viral breakthrough, and emergence of genotypic resistance did not differ significantly between the two patient groups. There were also no significant intergroup differences in the rates of disease progression (PD) and new development of hepatocellular carcinoma (HCC).

Conclusion

The long-term clinical outcomes of antiviral-naïve patients treated with ETV and LAM-resistant patients receiving ADV add-on LAM combination treatment were comparable in terms of the emergence of HCC and disease progression.

Antiviral Therapy in Lamivudine-Resistant Chronic Hepatitis B Patients: A Systematic Review and Network Meta-Analysis

The relative efficacy of different strategies for chronic hepatitis B (CHB) patients with lamivudine resistance (LAM-R) has not yet been systematically studied. Clinical trials were searched in PUBMED, MEDLINE, EMBASE, and CNKI databases up to February 15, 2016. Nine trials including 764 patients met the entry criteria. In direct meta-analysis, TDF showed a stronger antiviral effect than any one of ETV, LAM/ADV, and ADV against LAM-R hepatitis B virus. LAM/ADV therapy was superior to ADV in suppressing viral replication. ETV achieved similar rate of HBV DNA undetectable compared to ADV or LAM/ADV. In network meta-analysis, TDF had higher rates of HBV DNA undetectable compared to ETV (OR, 24.69; 95% CrI: 5.36–113.66), ADV (OR, 37.28; 95% CrI: 9.73–142.92), or LAM/ADV (OR, 21.05; 95% CrI: 5.70–77.80). However, among ETV, ADV, and LAM/ADV, no drug was clearly superior to others in HBV DNA undetectable rate. Moreover, no significant difference in the rate of ALT normalization or HBeAg loss was observed compared the four rescue strategies with each other. TDF appears to be a more effective rescue therapy than LAM/ADV, ETV, or ADV. LAM plus ADV therapy was a better treatment option than ETV or ADV alone for patients with LAM-R.

Efficacy of tenofovir-based rescue therapy in patients with lamivudine-resistant hepatitis B virus: A systematic review and meta-analysis

BACKGROUND

Currently, there are no conclusive results on the efficacy of Tenofovir disoproxil fumarate (TDF) monotherapy in chronic hepatitis B (CHB) patients with lamivudine-resistant (LAM-R).

OBJECTIVE

The aim of this study was to compare the efficacy between TDF and TDF-based combination therapy against LAM-R HBV in CHB patients.

METHODS

Randomized and non-randomized control trials directly comparing TDF and TDF-based therapy for treatment of LAM-R CHB patients, were searched in Pubmed, Medline, EMBASE, database up to June 15, 2015. The data were analyzed with Review Manager (v.5.3).

RESULTS

Five articles (683 patients in total) met entry criteria. The overall efficacy of tenofovir-based combination therapy was not significantly better with regard to the rates of virological response (85.5% vs. 81.5%; RR=0.95, 95%CI=0.88-1.03, P=0.25), ALT normalization (61.9% vs.72.0%; RR=1.18, 95%CI=0.96-1.44, P=0.11) and HBeAg loss (17.0% vs. 18.1%; RR=1.40, 95%CI=0.78-2.49, P=0.26) compared with TDF monotherapy through 48-week treatment. Additionally, subgroup analysis showed that no significant difference was determined as TDF group compared to TDF-based group at 48weeks, in terms of rates of HBV DNA undetectability, ALT normalization and HBeAg loss in the treatment of LAM-R patients with prior failure of LAM monotherapy. Moreover, the rates of HBV DNA suppression between groups were similar through 24 or 48weeks of treatment in LAM-R patients with prior failure of LAM/ADV therapy.

CONCLUSIONS

TDF monotherapy is as effective as TDF-based combination therapy in maintaining viral suppression in LAM-R patients with prior failure of LAM or LAM/ADV therapy.

Durability of the virological response after lamivudine discontinuation in lamivudine-resistant patients with a complete virological response after lamivudine and adefovir combination therapy

We investigated the durability of virological response after lamivudine (LAM) discontinuation in LAM-resistant chronic hepatitis B (CHB) patients with complete virological response after LAM-adefovir (ADV) combination therapy. We enrolled 58 patients switched to ADV monotherapy with undetectable viral loads (<12 IU/ml) and normal alanine aminotransferase levels after ADV add-on combination treatment for at least 6 months in LAM-resistant CHB patients. Virologic relapse was defined as HBV DNA detection at more than 20 IU/ml by quantitative polymerase chain reaction determined on two consecutive measurements. During median 40.9 months of follow-up (range 11.5-79.0 months), seven (12.1%) patients experienced virological relapse. The cumulative rate of virological relapse at 3 and 5 years was 5.5% and 22.4%, respectively. Two patients had elevated alanine aminotransferase during virological relapse. These seven patients with virological relapse had undetectable HBV DNA after switching to tenofovir therapy. In our study, switching to ADV monotherapy resulted in sustained HBV DNA suppression in 87.9% of the patients during median 40.9 months follow-up. This adapting step-down strategy, switching from combination therapy to monotherapy in virologically suppressed CHB patients with stable liver disease, may reduce the cost burden and the risk of potentially harmful effects of combination therapy. J. Med. Virol. 89:85-90, 2017. © 2016 Wiley Periodicals, Inc.

Cost-effectiveness comparison of lamivudine plus adefovir combination treatment and nucleos(t)ide analog monotherapies in Chinese chronic hepatitis B patients

BACKGROUND/AIM

Lamivudine (LAM) plus adefovir (ADV) combination therapy is clinically efficacious for treating chronic hepatitis B (CHB) patients in China, but no pharmacoeconomic evaluations of this strategy are available. The aim of this study was to examine the cost-effectiveness of LAM plus ADV combination treatment compared with five other nucleos(t)ide analog monotherapies (LAM, ADV, telbivudine [TBV], entecavir [ETV], and tenofovir [TDF]).

METHODS

To simulate the lifetime (40-year time span) costs and quality-adjusted life-years (QALYs) for different therapy options, a Markov model that included five initial monotherapies and LAM plus ADV combination as an initial treatment was developed. Two kinds of rescue combination strategies (base-case: LAM + ADV then ETV + ADV; alternative: direct use of ETV + ADV) were considered separately for treating patients refractory to initial therapy. One-way and probabilistic sensitivity analyses were used to explore model uncertainties.

RESULTS

In base-case analysis, ETV had the lowest lifetime cost and served as the reference therapy. Compared to the reference, LAM, ADV, and TBV had higher costs and lower efficacy, and were completely dominated by ETV. LAM plus ADV combination therapy or TDF was more efficacious than ETV, but also more expensive. Although the incremental cost-effectiveness ratios of combination therapy or TDF were both higher than the willingness-to-pay threshold of $20,466/QALY gained for the reference treatment, in an alternative scenario analysis LAM plus ADV combination therapy would be the preferable treatment option.

CONCLUSION

ETV and LAM plus ADV combination therapy are both cost-effective strategies for treating Chinese CHB patients.

Outcome of adefovir add-on lamivudine rescue therapy of up to 5 years in patients with lamivudine-resistant chronic hepatitis B

BACKGROUND AND AIM

We investigated the long-term efficacy of adefovir add-on lamivudine rescue therapy in lamivudine-resistant chronic hepatitis B and the optimal cutoff hepatitis B virus (HBV) DNA level that predicts complete virological response (CVR) among patients without CVR after 1 year of treatment.

METHODS

We reviewed 167 lamivudine-resistant chronic hepatitis B patients who received adefovir add-on rescue therapy for up to 5 years. Multivariate analysis, area under the receiver operating characteristic curves, and Youden index were used.

RESULTS

Median age was 47.0 years; 112 patients were male. Median baseline HBV DNA level was 6.6 log10 IU/mL; hepatitis B e antigen was positive in 130 (77.4%) patients. Five-year CVR, alanine aminotransferase normalization, hepatitis B e antigen seroconversion, and adefovir resistance rates were 86.9%, 92.5%, 16.7%, and 6.0%, respectively. One-year HBV DNA level independently associated with CVR. Optimal cutoff HBV DNA level to predict CVR among patients who failed to achieve CVR at 1 year was 800 IU/mL (area under receiver operating characteristic curve 0.752; sensitivity 49.3%, specificity 93.5%). During the 5-year treatment, 92.1% of patients with favorable response (HBV DNA < 800 IU/mL at 1 year) achieved CVR; 45.6% achieved CVR among suboptimal responders (HBV DNA ≥ 800 IU/mL at 1 year) (P < 0.001).

CONCLUSION

Complete virological response or HBV DNA level < 800 IU/mL after 1 year adefovir add-on lamivudine rescue therapy can favorably predict CVR.

Impact of nucleos(t)ide analogue combination therapy on the estimated glomerular filtration rate in patients with chronic hepatitis B

Monotherapy with telbivudine or adefovir can affect estimated the glomerular filtration rate (eGFR). However, only a few studies have assessed changes in eGFR in patients who have chronic hepatitis B (CHB) and are receiving nucleos(t)ide analogue (NA) combination therapy. In our study, we aimed to evaluate the effects of long-term NA combination therapy on eGFR in Chinese CHB patients. This retrospective study included 195 CHB patients. Patient subgroups included those treated with lamivudine plus adefovir (n = 73), telbivudine plus adefovir (n = 51), and entecavir plus adefovir (n = 35); untreated patients (n = 36) served as a control group. After an average follow-up duration of 24 months with combination therapy, analysis of changes in eGFR from baseline values, calculated by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) formulas, showed decrease by 11.08 and 18.34 mL/min (P < .001), respectively, in the lamivudine plus adefovir group; decrease by 3.73 and 10.04 mL/min (P = .012), respectively, in the entecavir plus adefovir group; and increase by 0.91 and 2.12 mL/min (P = .46), respectively, in the telbivudine plus adefovir group. The eGFR in the telbivudine plus adefovir group was similar to that for the untreated group. The eGFR decreases due to adefovir therapy could be rescued by adding telbivudine, and the eGFR increase due to telbivudine could be compromised by adding adefovir. Adefovir in combination with lamivudine or entecavir therapy was significantly associated with decreased eGFR, but telbivudine could rescue the eGFR decrease that results from adefovir treatment.

The feasibility of discontinuing lamivudine in lamivudine-resistant chronic hepatitis B patients on lamivudine and adefovir combination therapy

OBJECTIVES

This study investigated the antiviral efficacy of adefovir (ADV) rescue therapy and the feasibility of lamivudine (LAM) discontinuation in LAM-resistant chronic hepatitis B (CH-B) patients who had attained a virological response (VR) with LAM + ADV combination therapy.

METHODS

The VR and virological breakthrough (VBT) were analyzed in 106 consecutively enrolled LAM-resistant CH-B patients who received ADV rescue therapy during a mean follow-up period of 55.2 months. Seventy-four patients achieved VR, and were divided into the LAM-discontinuation group (n = 39) and the LAM-continuation group (n = 35). The VR and VBT between the 2 groups were compared.

RESULTS

For all 106 LAM-resistant CH-B patients, the overall cumulative probabilities of VR at 1, 2, 3 and 5 years of ADV rescue therapy were 40.6, 55.7, 64.6 and 81.3%, respectively. The cumulative probabilities of VBT at 1, 2, 3 and 5 years were 0, 2.9, 8.8 and 13.9%, respectively. Whether they discontinued or continued LAM after achieving VR on LAM + ADV therapy, VR and VBT were not significantly different during a mean follow-up period of 40.4 months.

CONCLUSIONS

There was a good long-term VR with ADV rescue therapy for LAM-resistant CH-B patients. Moreover, discontinuing LAM was found to be feasible for patients who attained VR during ADV + LAM therapy.

Efficacy and resistance in de novo combination lamivudine and adefovir dipivoxil therapy versus entecavir monotherapy for the treatment-naive patients with chronic hepatitis B: a meta-analysis

Background

Currently, there is no consensus on the efficacy and resistance of de novo combination therapy versus monotherapy for treatment naive patients of chronic hepatitis B (CHB).

Objectives

The aim of this study was to evaluate the effectiveness and resistance of de novo combination of lamivudine (LAM) and adefovir dipivoxil (ADV) compared with entecavir (ETV) monotherapy for nucleos(t)ide–naive patients with CHB.

Study design

Publications on the effectiveness and resistance of LAM plus ADV versus ETV monotherapy for nucleos(t)ide-naive patients with CHB were identified by a search of PubMed, Embase, the Cochrane Library, Web of science, OVID, and CBM (Chinese Biological Medical Literature) until May 1, 2013. Biochemical response, hepatitis B e antigen seroconversion, and viroligic response were extracted and combined to obtain an integrated result. Viral resistance and safety were reviewed.

Results

Five eligible studies (328 patients in total) were included in the analysis. LAM plus ADV combination therapy produced more rapid HBV DNA reduction rate at 12 weeks than that of ETV monotherapy. At 48 weeks, the combination group had superior viroligic response rates compared with ETV group (90.0% vs. 78.9%, P=0.01). The difference in the ALT normalization and HBeAg seroconversion rates was not found. At week 96, LAM + ADV was more effective than ETV in ALT normalization [RR = 1. 11, 95% CI (1.02, 1.21), P =0.01] and HBeAg seroconversion [RR = 2.00, 95% CI (1.26, 3.18, P=0.003)], and no significant difference was found in the virologic response (P =0.23). No viral resistance occurred in combination therapy and six patients in ETV group were experienced with viral breakthrough. Both groups were well tolerated.

Conclusion

The de novo LAM plus ADV combination therapy for treatment-naïve patients with CHB was greater than ETV monotherapy in both biochemical response and HBeAg seroconversion rate up to 96 weeks. The rate of emergence of viral resistance in the combination group was less than that in the ETV monotherapy.

Prolonged Combination Therapy is More Effective than Monotherapy in Management of Chronic Hepatitis B Patients With Sustained Virological Response: An Experience From a 'Real-World' Clinical Setting

BACKGROUND

Little is known about the duration of combination therapy for patients with chronic hepatitis B (CHB) and suboptimal response to nucleos(t)ide analogues(NAs) monotherapy.

OBJECTIVES

This study aimed to assess whether monotherapy could be used for treatment of CHB patients, who poorly responded to Adefovir Dipivoxil (ADV) but obtained good responses after at least 12-month lamivudine (LAM) or telbivudine (LdT) add-on therapy.

PATIENTS AND METHODS

Forty-five patients were enrolled, and the baseline time-point was determined according to enrollment data. Twenty-six patients chose to continue combination therapy (LAM+ADV or LdT+ADV, Group A) and 19 patients switched to single-drug maintenance therapy (LAM or LdT or ADV, Group B).

RESULTS

There were no significant differences between two groups in baseline characteristics (P > 0.05). At 12th month, sustained virological response rate was greater in group A compared to group B (96.2% vs. 47.4%, P < 0.001), and the rates of NAs-associated resistance were 0% in group A and 15.8% in group B. Alanine aminotransferase normalization rate was also significantly higher in group A compared with group B (92.3% vs. 36.8%, P < 0.001). Among hepatitis positive patients with Be antigen (HBeAg)-, 40% (4/10) in group A and 9.1% (1/11) in group B achieved HBeAg seroconversion at the 12th month. Of patients in group B with positive-HBeAg before the previous combination therapy and detectable HBV DNA at 6 months of previous combination therapy were associated with high risks of viral relapse after switching to single-drug maintenance therapy.

CONCLUSIONS

Prematurely switching to single-drug maintenance therapy would be resulted in viral relapse, and prolonged combination therapy was effective to maintain sustained responses for patients with initial suboptimal response to ADV.

Combination lamivudine and adefovir versus entecavir for the treatment of naïve chronic hepatitis B patients: a pilot study

BACKGROUND

The aim of this study was to compare the effect of combination lamivudine (LAM) and adefovir dipivoxil (ADV) versus entecavir (ETV) monotherapy for naïve HBeAg-positive chronic hepatitis B (CHB) patients.

MATERIAL/METHODS

Fifty enrolled patients with CHB were evenly divided into 2 groups: a group treated with of lamivudine (LAM) (100 mg/day) plus adefovir (ADV) (10 mg/day) combination, and a group treated with entecavir (ETV) (0.5 mg/day). Serum levels of ALT, AST, creatinine, bilirubin, HBsAg, HBeAg and HBV viral load, and genotypic resistance were analyzed at 0, 12, 24, 52, and 104 weeks. HBV DNA levels were determined by real-time PCR and HBsAg and HBeAg by chemiluminescence. Serum levels of ALT, AST, creatinine, and bilirubin were measured by an automatic biochemical analyzer. Data analysis was performed with SPSS 12.0 software.

RESULTS

There were no significant differences in the virological response (VR) rates between LAM+ADV and ETV cohorts at 24, 52, and 104 weeks (P>0.05). The HBeAg seroconversion rates were 28% and 20%, and the biochemical response (BR) rates were 88% and 84% at week 104 in the LAM+ADV and ETV groups, respectively. The rates of undetectable HBV DNA, HBeAg seroconversion, and ALT normalization rates were similar in both cohorts. No virological breakthrough or serious adverse effects were noted for any patient during the study period.

CONCLUSIONS

Both LAM+ADV combination therapy and ETV monotherapy were effective and safe in the treatment of -naïve HBeAg-positive CHB patients. However, further studies are needed to obtain long-term results.

Entecavir plus adefovir rescue therapy for chronic hepatitis B patients after multiple treatment failures in real-life practice

Aim

To evaluate the efficacy and safety of Entecavir (ETV) plus adefovir (ADV) for chronic hepatitis B (CHB) patients after multiple nucleos(t)ide analogue (NAs) failure treatment.

Methods

Hepatitis B e antigen (HBeAg)-positive patients who had a suboptimal response or developed resistance to two or more previous NAs treatments were included, and all subjects were treated with ETV in combination with ADV for ≥ 24 months. Complete virologic response (CVR) was defined as an undetectability of serum hepatitis B virus (HBV) DNA level during treatment. Safety assessment was based on the increasing of serum creatinine and creatine kinase levels.

Results

A total of 45 eligible patients were included. Twenty-five patients had been treated with lamivudine (LAM) or telbivudine (LdT) and developed genotypic resistance. Resistance to ADV was present in 18 patients and 4 patients had a suboptimal response to ETV. Two patients had a resistance to both LAM and ADV. The cumulative probabilities of CVR at 12 and 24 months of ETV + ADV treatment were 88.9% (40/45) and 97.8% (44/45), respectively. Although one patient failed to achieve CVR, its serum HBV DNA level decreased by 3.3 log copies/mL after 24 months of combination therapy. The cumulative probability of HBeAg seroconversion was 15.6% (7/45) and 26.7% (12/45) at 12 and 24 months of treatment, respectively. History of prior exposure to specific NAs did not make a difference to ETV + ADV treatment outcome. There were no significant adverse events related to ETV + ADV therapy observed in the study subjects.

Conclusion

ETV + ADV can be used as an effective and safe rescue therapy in patients after multiple NA therapy failures, especially in the areas where tenofovir is not yet available.

Efficacy of telbivudine treatment for hepatitis B e antigen-positive chronic hepatitis B patients with poor response to adefovir dipivoxil

Telbivudine (LdT) has demonstrated potent antiviral activity in nucleos(t)ide analogue (NA)-naïve chronic hepatitis B patients (CHB), but data on its efficacy in NA-experienced patients are limited. The aim of this study was to investigate the effect of LdT in hepatitis B e antigen-positive CHB patients with poor response to initial adefovir dipivoxil (ADV). Forty-two CHB patients with HBV DNA > 4 log10  copies/mL after 12 months of ADV monotherapy were enroled in the study and thereafter treated with LdT 600 mg daily for 18 months. Telbivudine led to a rapid decrease in viral load, and viral replication was persistently suppressed with a reduction of 2.26 log10  copies/mL 18 months after LdT treatment. The rates corresponding to virological and biochemical response at the end of observation were 97.6% (41/42) and 65.8% (25/38), respectively. HBeAg loss was found in 30.8% (12/39) of patients, while HBeAg/anti-HBe seroconversion was found in 17.9% (7/39). Only one patient was detected to have LdT-associated mutation, and no severe adverse events were reported. Optimization therapy with LdT monotherapy may be a good choice for CHB patients with poor response to ADV, and switching to LdT may be the most cost-effective rescue therapeutic strategy for patients with poor response to initial ADV monotherapy.

Efficacy and safety of telbivudine plus adefovir dipivoxil combination therapy and entecavir monotherapy for HBeAg-positive chronic hepatitis B patients with resistance to adefovir dipivoxil

The objective of this study was to compare the efficacy and safety of two rescue strategies for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients with resistance to adefovir dipivoxil (ADV). This prospective study included 58 HBeAg-positive CHB patients with resistance to ADV; 30 patients underwent telbivudine (LdT) plus ADV combination therapy and 28 patients switched to entecavir (ETV) monotherapy. After 48 weeks of treatment, the rates of hepatitis B virus (HBV) DNA <3 log10 copies/mL in the LdT plus ADV group and the ETV group were not significantly different (73.3% vs 57.1%, P = 0.195). Six patients receiving LdT plus ADV had HBeAg seroconversion, while none of the patients receiving ETV alone had HBeAg seroconversion (20% vs 0%, P = 0.039). During the 48-week treatment period, two patients in the ETV monotherapy group had viral breakthrough and the strains were confirmed to be of a variant associated with ETV resistance (rtM204V+ rtL180M+ rtT184G), while one patient receiving LdT plus ADV had viral breakthrough and an LdT-associated resistance mutation (rtM204I) was detected. For the majority of the patients, both LdT plus ADV combination treatment or ETV monotherapy were generally well tolerated, and no serious side effects were observed. Both LdT plus ADV combination therapy and ETV monotherapy led to significant decreases in serum HBV DNA in HBeAg-positive CHB patients with resistance to ADV, and LdT plus ADV combination therapy exhibited a significantly higher rate of HBeAg seroconversion compared with ETV monotherapy.

Hepatitis B viral factors and treatment responses in chronic hepatitis B

Baseline and on-treatment hepatitis B viral factors are reported to affect treatment responses. A lower baseline hepatitis B virus (HBV) DNA level is a strong predictor of the response to antiviral therapy. HBV genotype A/B patients have better responses to interferon-based therapy than those with genotypes C/D. Regarding the association of HBV mutants with responses to antiviral therapy, current evidence is limited. On-treatment viral suppression is the most important predictor of response to nucleoside analogs. On-treatment hepatitis B surface antigen decline is significantly associated with response to pegylated interferon. In the future, individualized therapy should be based on treatment efficacy, adverse effects, baseline and on-treatment predictors of antiviral therapy.

Efficacy of 3 years of adefovir monotherapy in chronic hepatitis B patients with lamivudine resistance

AIM

To study the effect of rescue monotherapy with adefovir (ADV) in patients with chronic hepatitis B (CHB) who developed drug resistance to lamivudine (LAM).

METHODS

A total of 76 treated CHB patients with resistance to LAM were enrolled in the present study. The patients' baseline characteristics, such as age, gender, blood tests and hepatitis B virus (HBV) DNA were collected; therapy duration and the response of each patient were also recorded. ADV monotherapy was set as the observation group A. Twenty-four patients with LAM resistance, who were set as group B, accepted combined therapy with LAM + ADV. Patients were followed up at 0, 12, 24, 52, 104 and 156 wk. Hepatitis B surface antigen status, hepatitis B e antigen (HBeAg)/anti-HBe status, HBV DNA level and biochemical indexes were monitored. Sequencer of HBV polymerase gene was performed on the ABI 3730 automated sequencer. If no desired effects had been achieved during the course of treatment, patients' choices were also taken into account. The control group was tested at the same time.

RESULTS

In the two groups, 27 cases developed viral breakthrough after LAM treatment response. The remaining 49 cases underwent biochemical rebound accompanied by rtM204I/V or rtL180M mutation. In group A, 52 cases finished 156 wk of ADV monotherapy; of whom, 36 cases were HBeAg positive and 16 HBeAg negative. In patients whose baseline HBV DNAs were 10(3)-10(5) copies/mL, 88.8% of patients' HBV DNAs were lower than the lower test limit (10(3) copies/mL) after 12 to 156 wk of ADV treatment. In patients whose baseline HBV DNAs were ≥ 10(6) copies/mL, 41.1%-47.0% of patients' HBV DNAs were lower than the lower test limit after the same course of ADV therapy (χ(2) were 4.35-5.4, 41.1%-47.0% vs 88.8% group 10(3)-10(5) copies/mL, P < 0.01). In group A, seroconversion of HBeAg developed in 8 of 36 cases (22.2%). In group B, 24 cases finished 156 wk of LAM + ADV; of whom, 17 cases were HBeAg positive and 7 HBeAg negative. In patients whose baseline HBV DNAs were 10(3)-10(5) copies /mL, 81.8% of patients' HBV DNAs were lower than the lower test limit (10(3) copies/mL) after 12 to 156 wk of treatment. In the patients whose baseline HBV DNAs were ≥ 10(6) copies/mL, 46.1%-53.8% of patients' HBV DNAs were lower than the lower test limit after the same course of LAM + ADV therapy (χ(2) were 4.1-5.0, 46.1%-53.8% vs 81.8% group 10(3)-10(5) copies/mL, P < 0.05-0.01). In group B, 4 of 17 cases (23.5%) developed seroconversion of HBeAg. Treatment outcomes in groups A and B were comparable.

CONCLUSION

In both group A and B, the ratios of virological response have similar efficacy in patients with lower baseline HBV DNAs.

Custo-efetividade dos análogos de nucleosídeos/nucleotídeos para hepatite crônica B

OBJETIVO: Conduzir uma análise de custo-efetividade das alternativas medicamentosas com terapia de resgate na recaída por resistência viral para tratamento de pacientes com hepatite crônica B (HCB). MÉTODOS: Coorte hipotética de pacientes com HCB, HBeAg negativo, sem evidência clínica ou histológica de cirrose, DNA do VHB detectável, diagnóstico histológico da doença, HBsAg positivo no soro por mais de seis meses, elevados níveis de alanina transferase (ALT) (duas vezes maior que o limite superior da normalidade [LSN]) e média de idade de 40 anos. Modelo de Markov foi desenvolvido para a hepatite crônica B (antígeno HBeAg negativo) com horizonte temporal de 40 anos. Custos e benefícios foram descontados em 5%. As taxas anuais de progressão, custos devido a complicações e a eficácia dos medicamentos foram obtidos da literatura. As incertezas foram avaliadas por análises de sensibilidade unidirecional e probabilística. RESULTADOS: Iniciar o tratamento com entecavir resultou em 0,35 ano de vida ganho em relação à lamivudina. A razão de custo-efetividade incremental foi de R$ 16.416,08 por anos de vida ganhos. Na análise de sensibilidade a razão de custo-efetividade incremental foi mais sensível à variação na probabilidade de transição de hepatite crônica B para cirrose compensada, taxa de desconto e preço dos medicamentos (± 10%). Na análise de sensibilidade probabilística, a curva de aceitabilidade mostrou que iniciar com entecavir foi a alternativa mais custo-efetiva na comparação ao uso de lamivudina. CONCLUSÕES: A disponibilidade do entecavir é economicamente atrativa como parte do tratamento precoce para pacientes com hepatite crônica B sem coinfecção com o HIV.

Clonal evolution of hepatitis B virus polymerase gene mutations during lamivudine-adefovir combination treatment

AIM: To identify hepatitis B virus polymerase gene mutations during antiviral therapy using lamivudine-adefovir sequential monotherapy followed by lamivudine-adefovir combination therapy.

METHODS: The patient cohort included four adult chronic hepatitis B patients who had undergone sequential monotherapy, first with lamivudine (LMV) and then, after developing viral breakthrough, with adefovir (ADV) therapy. All of the patients had non-response or viral breakthrough after LMV-ADV sequential monotherapy, which resulted in the switching of their antiviral regimen to LMV-ADV combination therapy. Eleven serum samples from the four patients who showed non-response to rescue LMV-ADV combination therapy were collected sequentially at a time before the antiviral treatment and then during the LMV monotherapy, ADV monotherapy, and LMV-ADV combination therapy. For the genotypic analysis, the whole 1310-bp polymerase gene region was amplified, cloned and sequenced.

RESULTS: All patients had been previously treated with 100 mg of LMV once daily for a 15- to 26-mo period. The emergence of resistance mutations to LMV, such as rtM204V/I and/or rtL180M, were found in all patients. Their antiviral regimens were switched to ADV monotherapy as the second line treatment. All patients had viral breakthrough or non-response after the LMV-ADV sequential monotherapy. ADV-resistant mutations were detected after 13 to 19 mo of LMV-ADV sequential monotherapy. The rtA181V/T mutations were predominantly identified during the ADV treatment in the LMV-resistant patients. Twenty-seven of 38 clones were combined with an amino acid change at rt181; three clones had mutations in rt236 and one clone had a combined mutation. The rtA181V/T mutations were not suppressed by the LMV-ADV combination therapy. Thirty-nine of 64 clones showed an rtA181V/T mutation and six clones showed combined mutations in rt181 and rt236. Mutations in rt204 re-emerged during the combination treatment. The rt181 and rt204 mutations did not co-exist in one clone.

CONCLUSION: Add-on lamivudine therapy with adefovir for adefovir resistance may not suppress the pre-existing adefovir-resistant mutation that develops during lamivudine-adefovir sequential monotherapy.

Correlation between pretreatment viral sequences and the emergence of lamivudine resistance in hepatitis B virus infection

The emergence of amino acid or nucleotide substitutions leads to lamivudine resistance in hepatitis B virus (HBV) infected patients. The aim of this study was to investigate whether viral sequences help predict the emergence of lamivudine resistance. The study subjects comprised 59 consecutive patients infected with HBV treated with daily therapy of 100 mg lamivudine. Among those, 32 patients with adequate pretreatment serum preservation were investigated for the correlation between viral amino acid substitutions and the appearance of lamivudine resistance with consideration of clinical background by determining dominant HBV full open reading frames. Viral resistance to lamivudine emerged in 28 of 59 patients (47%) in a median period of 2.45 years. Sequence comparisons of HBV genomes between patients who later developed lamivudine resistance and patients who did not revealed the existence of significant differences between the two groups in the pre-S1 84 (P = 0.042), pre-S2 1 (P = 0.017) and 22 (P = 0.015), and polymerase tp 95 (P = 0.046), judged by a log-rank test. Viral sequence analyses revealed the presence of amino acid substitutions in HBV pre-S1 and pre-S2 that may be associated with the emergence of lamivudine resistance during chronic HBV infection.

Cost-effectiveness analysis of different rescue therapies in patients with lamivudine-resistant chronic hepatitis B in China

Background

Several rescue therapies have been used in patients with lamivudine (LAM)-resistant chronic hepatitis B (CHB); however, the economic outcome of these therapies is unclear. The object of the current analysis was to evaluate the lifetime cost-effectiveness of rescue therapies among patients with LAM-resistant CHB.

Methods

A Markov model was developed to simulate the clinical course of patients with LAM-resistant CHB. From the perspective of Chinese health care, a lifetime cost-utility analysis was performedfor 4 rescue strategies: adefovir (ADV), entecavir (ETV) or tenofovir (TDF) monotherapy and combination therapy using LAM and ADV. A hypothetical cohort of 45-year-old patients with genotypic or clinical LAM-resistant CHB entered the model, and the beginning health state was LAM-resistant CHB without other complications. The transition probabilities, efficacy and resistance data for each rescue therapy as well as the costs and utility data were estimated from the literature. The discount rate (3%) utilized for costs and benefits. Sensitivity analyses were used to explore the impact of uncertainty on the results.

Results

In LAM-resistant HBeAg-positive and HBeAg-negative CHB cohorts, TDF monotherapy and combination therapy were on the efficiency frontier for both positive and negative populations. Compared with no treatment, the use of combination therapy cost an additional $6,531.7 to gain 1 additional quality-adjusted life year (QALY) for HBeAg-positive patients and $4,571.7 to gain 1 additional QALY for HBeAg-negative patients. TDF monotherapy for HBeAg-positive patients, shows greater increase in QALYs but higher incremental cost-effectiveness ratio (ICER) in comparison with combination therapy. In probabilistic sensitivity analyses, combination therapy was the preferred option for health care systems with limited health resources, such as Chinese health care system.

Conclusion

In Chinese patients with LAM-resistant CHB, combination therapy is a more cost-effective option than the competing rescue therapies.

A case of adefovir-induced membranous nephropathy related to hepatitis B caused by lamivudine-resistant virus after liver transplant due to Byler's disease

We report on how adefovir-induced membranous nephropathy related to hepatitis B was caused by lamivudine-resistant virus after a liver transplant due to Byler's disease. In 1980, a 2-year-old girl was diagnosed with Byler's disease (familial progressive familial intrahepatic cholestasis). In 1994 (at the age of 14 years) she underwent a liver transplant with her father as the donor. In 2003, hematuria and proteinuria appeared and shortly afterwards her renal function rapidly decreased. A renal biopsy showed atypical membranous nephropathy, which suggested the possibility of a secondary renal disease. The patient had suffered from chronic hepatitis type B (HBV). In 2001 she was administered lamivudine which is an antiviral drug; it was around this time that hematuria and proteinuria appeared as well as an increase of the virus titer. We believed the HBV-related membranous nephropathy was the cause of the virus titer and the renal histology. We concluded that the patient's condition had become resistant to lamivudine medication. Therefore, in February 2004 we administered adefovir, a new drug at the time, to treat the HBV. In April 2004, the HB virus titer decreased and the hematuria and proteinuria decreased. The patient's renal function also showed improvement. HBV-associated nephropathy is caused by HBV antigen deposition in the glomeruli. Generally the first choice of treatment is antivirus therapy. There are many reports demonstrating that administration of interferon and lamivudine are effective; however, there are few reports that show adefovir as an effective treatment for HBV-associated nephropathy.

Lamivudine plus adefovir or telbivudine plus adefovir for chronic hepatitis B patients with suboptimal response to adefovir

BACKGROUND

There is no standard management of chronic hepatitis B (CHB) patients with suboptimal response to nucleoside/nucleotide analogues (NAs). This study aimed to evaluate two different NA combination therapies in patients with suboptimal response to adefovir (ADV).

METHODS

In this study, 72 CHB patients with suboptimal response to ADV were assessed, with 37 patients receiving lamivudine plus ADV (group A) and 35 patients receiving telbivudine plus ADV (group B).

RESULTS

Baseline characteristics between two groups were similar. At month 12, rates of biochemical response (BR) and virological response (VR) were similar between groups A and B (17/19 versus 18/20 for BR, [P=0.269] and 30/37 versus 31/35 for VR [P=0.377]), and cumulative rates of serological response were greater in group B than in group A (10/26 versus 2/28 in hepatitis B e antigen [HBeAg] loss [P=0.006] and 7/26 versus 1/28 in HBeAg/hepatitis B e antibody seroconversion [P=0.022]). After 12-month treatment, 8.1% (3/37) of patients in group A and 5.7% (2/35) of patients in group B had VR; among patients in group A, two had rtM204V/I and rtL180M and one had rtN236T, whereas the two patients in group B had rtM204I+rtL180M.

CONCLUSIONS

Both combination therapies led to a significant decrease in HBV DNA. HBeAg serological outcomes were higher with telbivudine plus ADV combination therapy.

Antiviral therapy for hepatitis B infection during pregnancy and breastfeeding

It is estimated there are 350-400 million people worldwide chronically infected with HBV. Many of these are women and of reproductive age. As such, they may face therapeutic decisions regarding antiviral therapy and the implication this may have on future or current pregnancies. This article reviews the data of all antivirals licensed for use against hepatitis B infection regarding teratogenicity, carcinogenicity, clinical experience during pregnancy, placental transfer and excretion in breast milk.

Laboratory evaluation of three regimens of treatment of chronic hepatitis B: tenofovir, entecavir and combination of lamivudine and adefovir

BACKGROUND

Chronic hepatitis B is a disease of concern due to its life-threatening complications like cirrhosis, and hepatocellular carcinoma (HCC) in 20-40% of patients. There are about 400 million people affected worldwide with HBV, and over 300,000 die every year from HBV-related diseases. Oral antivirals like lamivudine, adefovir, entecavir, and tenofovir are commonly used to treat chronic hepatitis B. In this study, we tried to evaluate the comparative efficacy of these drugs alone and in combination.

MATERIALS AND METHODS

Chronic hepatitis B patients with HBV-DNA more than 10⁴Copies/mL irrespective of their HBeAg status (n=60) were enrolled in a prospective study. 21, 20, and 19 patients were treated with lamivudine (100 mg/day) plus adefovir (10 mg/day) combination entecavir monotherapy (0.5 mg/day) and tenofovir monotherapy (300 mg/day), respectively and were followed up for 24 weeks with their virological, serological, and biochemical markers measured at 12 and 24 weeks.

RESULTS

After 24 weeks of treatment, there was no significant difference between the 3 groups in suppressing HBV-DNA to undetectable levels. The median decrease in HBV-DNA levels from baseline was better with tenofovir and entecavir monotherapies than lamivudine and adefovir combination, which was statistically significant. There was no significant difference between the 3 groups in HBsAg and HBeAg seroconversion and normalization of biochemical parameters.

CONCLUSION

Entecavir and tenofovir monotherapy were found to be more effective than lamivudine plus adefovir combination in reducing the HBV-DNA levels. However, lamivudine plus adefovir combination was not too inferior, especially when cost of treatment was taken into consideration.

Factors predicting the efficacy of adefovir dipivoxil on treatment-naïve chronic hepatitis B patients at 48 weeks

Background/Aims

To reveal possible factors predicting the effect of adefovir dipivoxil (ADV) treatment on chronic hepatitis B (CHB) and optimize the utilization of ADV.

Methods

In total, 168 treatment-naïve CHB patients were enrolled, including 117 hepatitis B e antigen (HBeAg)-positive patients and 51 HBeAg-negative patients who met the inclusion criteria. All patients were treated with ADV 10 mg per day for 48 weeks. Multiple logistic regression analyses were used to investigate baseline factors, and responses at weeks 12 and 24 were analyzed as predictive values.

Results

Multiple regression analyses showed that baseline HBeAg status and HBV DNA levels significantly affected the virological response (VR) (p<0.05), baseline ALT levels were an independent predictor of serological response (SR) (p<0.05) and the body mass index (BMI) may affect the biochemical response (BR) (p<0.05). There was a statistically significant difference in the VR and SR between patients with a primary nonresponse (PNR) at week 12 and those with a VR at week 12 (p<0.01). Additionally, the VR was significantly different between patients with HBV DNA lower than 10³ copies/mL at week 24 and those with greater than 10³ copies/mL (p<0.01).

Conclusions

Patients with negative HBeAg, lower HBV DNA levels and higher ALT values at baseline are more suitable for ADV treatment, whereas patients with lower BMIs may be more amenable to ALT normalization. Adjustments for treatment strategy should be considered if PNR at week 12 or HBV DNA ≥10³ copies/mL at week 24 is observed.

Telbivudine in combination with adefovir versus adefovir monotherapy in HBeAg-positive, lamivudine-resistant chronic hepatitis B

PURPOSE

Lamivudine (LAM) resistance is common on lamivudine monotherapy for chronic hepatitis B. This study examined the safety and efficacy of telbivudine (LDT) given with adefovir (ADV) versus ADV monotherapy in patients with chronic, lamivudine-resistant HBV infection.

METHODS

An open-label, 96 week study with planned recruitment of 150 HBeAg-positive, lamivudine-experienced Asian patients with a confirmed YMDD resistance mutation, randomized 1:1 to receive ADV alone or with LDT. The study was terminated early due to difficulty in enrolling monotherapy patients. At termination, 42 patients had received study medication for 8-61 weeks. Due to incomplete enrolment, summary statistics only were prepared, without significance testing.

RESULTS

A total of 42 patients underwent rescue therapy (switch to ADV or LDT + ADV; n = 21 per group). Median treatment duration was 48 weeks in both groups. HBV DNA changes from baseline were greater in the LDT + ADV arm at all time points (Week 48: -7.4 log10 vs. -4.9 log10 copies/ml), and serum DNA was undetectable (<300 copies/mL) at week 48 in 38.5% (5/13) on LDT + ADV versus 0% (0/9) on ADV monotherapy Two patients (9.6%) on ADV monotherapy experienced virologic breakthrough without evidence of ADV resistance, but none on LDT + ADV; and no confirmed ADV resistance was observed in any on-treatment sample. HBeAg loss occurred in three patients on LDT + ADV and one patient on ADV monotherapy through week 48. Safety profiles were similar between the arms.

CONCLUSION

LDT + ADV combination treatment showed better outcomes against lamivudine resistant HBV than ADV alone, with a similar safety profile.

Management options for lamivudine-resistant chronic hepatitis B patients with suboptimal virological suppression by adefovir

BACKGROUND

In chronic hepatitis B (CHB) patients, adefovir is commonly used as a rescue therapy for lamivudine resistance, but often results in incomplete virological suppression.

AIM

To study the factors predicting response to adefovir rescue, and the treatment response of tenofovir and entecavir in suboptimal responders to adefovir in CHB patients.

METHODS

Chronic hepatitis B patients who took adefovir for at least 6 months for lamivudine resistance were studied. Early virological response was defined as undetectable HBV DNA at month 6. Maintained virological response was defined as undetectable HBV DNA till the last follow-up.

RESULTS

Among 136 patients on adefovir for 39 (5-117) months, 30 (22%) had early virological response. The 3-year cumulative probability of maintained virological response was similar between patients on adefovir monotherapy (n = 53, 57.9%) and those on combination of lamivudine and adefovir treatment (n = 83, 56.5%). The month 6 HBV DNA was the only independent factor associated with maintained virological response (adjusted hazard ratio 0.49, 95% confidence interval 0.37-0.65, P < 0.001). Twenty-six of 30 (87%) early responders and 36 of 106 (34%) non-early responders had maintained virological response on adefovir (P < 0.001). Among 106 non-early responders, 18 and 11 were switched to tenofovir and entecavir, respectively. The 1-year cumulative probability of maintained virological response was higher in patients switched to tenofovir (87.5%) than those switched to entecavir (37.5%; P = 0.048) or continued with adefovir (8.7%; P < 0.001).

CONCLUSIONS

In adefovir rescue for lamivudine resistance, month 6 HBV DNA predicts maintained virological response in CHB patients. Switching to tenofovir achieved best viral suppression among suboptimal responders to adefovir.

Lamivudine plus adefovir combination therapy versus entecavir monotherapy for lamivudine-resistant chronic hepatitis B: a systematic review and meta-analysis

Background

Chronic hepatitis B virus (HBV) infection represents a serious global health problem and resistance to lamivudine (LAM) has become a serious clinical challenge. Previous rescue therapy for the treatment of chronic LAM-resistant hepatitis B infected patients included switching to entecavir (ETV) and adding adefovir (ADV) or tenofovir (TFV). At present, switching to ETV is not recommended for rescue therapy for LAM-resistant chronic hepatitis B (CHB). The aim of this report was to determine whether add-on ADV was a superior rescue strategy in the treatment of CHB patients with LAM resistance.

Methods

We searched Medline/PubMed, EMBASE, Web of Knowledge, and the Cochrane Library. Relative risks (RRs) of virologic response, virologic breakthrough, normalization of serum alanine aminotransferase (ALT) levels and HBeAg seroconversion rates were studied. Factors predicting virologic response, standardized mean differences (SMD) in HBV DNA levels and safety were reviewed.

Results

Six eligible trials (451 patients in total) were included in the analysis. The rate of virologic breakthrough in the ETV group was higher than that in the LAM plus ADV group. There were no statistical differences in virologic response, ALT normalization and HBeAg seroconversion in either group 48 weeks post treatment. LAM plus ADV combination therapy produced faster and greater HBV DNA reduction rates 24 weeks post therapy compared to ETV monotherapy. HBV DNA baseline levels and the initial virologic response (IVR) were predictive of the virologic response. Additionally, combination therapy or monotherapy were both well tolerated.

Conclusions

LAM plus ADV combination therapy was more effective and produced longer-lasting effects than switching to ETV monotherapy in treating CHB patients with LAM resistance. However, considering the practical benefits and limitations of ADV, individualized therapy will be needed in patients with prior history of LAM resistant infections.

Lamivudine plus adefovir is a good option for chronic hepatitis B patients with viral relapse after cessation of lamivudine treatment

Aim

Currently, there is no consensus on the retreatment recommendation of chronic hepatitis B (CHB) patients with viral rebound after cessation of treatment. In the search of reasonable treatment, we compared the efficacy and safety of adefovir (ADV) plus lamivudine (LAM) and LAM alone for the retreatment of patients with viral relapse but without genotypic resistance after cessation of LAM.

Methods

This is a prospective controlled study, and a total of 53 hepatitis B e antigen (HBeAg)-positive patients with viral rebound but without resistance were received either LAM plus ADV or LAM alone treatment.

Results

After 1-year treatment, more patients who received LAM plus ADV than those who received LAM alone had ALT normalization (84% versus 53.6%, P = 0.018) or HBV DNA levels below 1000 copies/mL (80% versus 42.9%, P < 0.006). Seven patients receiving LAM plus ADV had HBeAg seroconversion, as compared with 0 in patients receiving ALM alone (28% versus 0%, P = 0.003). During 1-year retreatment, five patients receiving LAM alone had virological breakthrough and all of them had LAM resistance strains (rtM204V/I), while no LAM- or ADV- associated resistance strains were detected in patients receiving LAM plus ADV. All patients receiving LAM plus ADV were well tolerated, and no serious side effects were noted.

Conclusions

Patients treated with LAM plus ADV exhibited significantly greater virological, biochemical and serological responses compared with LAM alone. These data suggested that combination of LAM plus ADV would be a good option for the retreatment of CHB patients with viral relapse after cessation of LAM.

Combination Therapy for Chronic Hepatitis B: Current Indications

Hepatitis B infection remains a major public health problem globally and in the United States, with significant use of healthcare resources. Several therapeutic agents active against viral and host targets are currently available for its treatment. The success of combination therapy in HIV infection, which has similarities to hepatitis B in both therapeutic targets and treatment options, stimulated studies on the efficacy and safety of various combinations of available drugs in the treatment of hepatitis B infection. In this review, we analyze the current role of combination therapy in chronic hepatitis B infection.

[Analogs combination therapy in chronic hepatitis B: when and how?]

Hepatitis B virus (HBV) genomic variability is responsible for the complexity of the viral quasi-species and its evolution during the course of infection. The persistence of infected cells promotes the selection of drug-resistant strains. The development of nucleoside analogs without cross-resistance has provided a rationale for combination therapy. De novo combination, with low genetic barrier drugs, prevents the emergence of resistance in the short-term for drugs with a low genetic barrier and improves the control of infection. Long-term studies are needed to determine whether de novo combination is beneficial for analogs with a high genetic barrier as well. The add-on strategy is a standard in case of emergence of resistant mutants. This strategy needs to be implemented as early as possible before the virological breakthrough, especially if the viral suppression is sub-optimal. Clinical trials are mandatory in order to assess whether a) de novo combination is better than an early add-on strategy; and b) whether in case of sub-optimal viral suppression, an early add-on strategy is better in the long-term than a switch to a more potent drug with a high genetic barrier.

Comparison of the efficacy of tenofovir and adefovir in the treatment of chronic hepatitis B: a systematic review

Chronic viral hepatitis B remains a global public health concern. Currently, several drugs, such as tenofovir and adefovir, are recommended for treatment of patients with chronic hepatitis B. tenofovir is a nucleoside analog with selective activity against hepatitis b virus and has been shown to be more potent in vitro than adefovir. But the results of trials comparing tenofovir and adefovir in the treatment of chronic hepatitis B were inconsistent. However, there was no systematic review on the comparison of the efficacy of tenofovir and adefovir in the treatment of chronic hepatitis B. To evaluate the comparison of the efficacy of tenofovir and adefovir in the treatment of chronic hepatitis B we conducted a systematic review and meta-analysis of clinical trials. We searched PUBMED, Web of Science, EMBASE, CNKI, VIP database, WANFANG database, the Cochrane Central Register of Controlled Trials and the Cochrane Database of Systematic Review. Finally six studies were left for analysis which involved 910 patients in total, of whom 576 were included in tenofovir groups and 334 were included in adefovir groups. At the end of 48-week treatment, tenofovir was superior to adefovir at the HBV-DNA suppression in patients[RR = 2.59; 95%CI(1.01-6.67), P = 0.05]. While there was no significant difference in the ALT normalization[RR = 1.15; 95%CI(0.96-1.37), P = 0.14], HBeAg seroconversion[RR = 1.32; 95%CI(1.00-1.75), P = 0.05] and HBsAg loss rate[RR = 1.19; 95%CI(0.74-1.91), P = 0.48]. More high-quality, well-designed, randomized controlled, multi-center trails are clearly needed to guide evolving standards of care for chronic hepatitis B.

Long-term nucleos(t)ide analogues therapy for adults with chronic hepatitis B reduces the risk of long-term complications: a meta-analysis

Background

The effect of antiviral therapy in chronic hepatitis B (CHB) on reducing the risk of long-term complications (LTCs) remains unclear so far. To study whether long-term nucleos(t)ide analogues therapy can reduce the risk of long-term complications.

Methods

We searched MEDLINE, EMBASE, OVID, the Cochrane Central Register of Controlled Trials. Relative risks (RRs) of long-term complications with or without treatment were studied. Also subgroup analyses including the status of drug-resistance, HBeAg and pre-existing compensated cirrhosis were done using relative risks of long-term complications either with or without treatment or among nucleos(t)ide analogues treatment groups.

Results

Six eligible studies (3644 patients in all) were included. Data showed the incidence of long-term complications in treatment groups was induced by 74%(RR:0.26, 95% CI: 0.15-0.47) compared with no treatment. Whether drug-resistant happened or not during the long-term therapy, the incidence of long-term complications was still significantly induced respectively by 45%(RR: 0.55,95%CI:0.40-0.76) and 78% (RR:0.22, 95%CI: 0.13-0.36). For both different status of HBeAg and pre-existing compensated cirrhosis, there was significant lower incidence of long-term complications in treatment groups compared with no treatment, too. Moreover, among the NA treatment groups, patients with drug-resistance had 2.64 times (RR:2.64, 95%CI: 1.58-4.41) higher chance of developing to long-term complications, and patients with pre-existing compensated cirrhosis also had 3.07 times (RR:3.07, 95%CI: 1.04-9.11) higher chance of developing to long-term complications.

Conclusions

Long-term nucleos(t)ide analogue therapy for adults with CHB prevents or delays the development of long-term complications including decompensated cirrhosis, CHB-related death or CHB-related HCC in patients with CHB. The patients who need take antiviral drugs should receive the antiviral therapy as soon as possible.

De novo combination of lamivudine and adefovir versus entecavir monotherapy for the treatment of naïve HBeAg-negative chronic hepatitis B patients

PURPOSE

Either combination treatment or monotherapy using agents with a high genetic barrier are recommended for hepatitis B e antigen (HBeAg)-negative chronic hepatitis B (CHB). The aim of this study was to compare effect of naïve HBeAg-negative CHB patients with either de novo combination of lamivudine (LAM) and adefovir dipivoxil (ADV) or entecavir (ETV) monotherapy.

METHODS

HBeAg-negative CHB patients (n = 71) with ALT levels between 2 and 10 times the upper normal limit and HBV DNA levels >10(4) copies/mL were enrolled. Patients were treated with either LAM 100 mg plus ADV 10 mg per day (n = 31) or ETV 0.5 mg per day (n = 40) for 48 weeks.

RESULTS

The average reduction in HBV DNA level compared with baseline were 5.16 ± 1.69 log in the LAM + ADV group and 5.36 ± 1.70 log in the ETV group by week 48 (P = 0.624). The virological response (VR) rates were 80.65 and 77.5%, the biochemical response (BR) rates were 93.55 and 90.00% at week 48 in the LAM + ADV and ETV groups, respectively. There was no significant difference in the VR and BR between the two groups. During the 48-week treatment period, virological breakthrough and serious side effects were not noted in any patient.

CONCLUSIONS

Both LAM + ADV combination therapy and ETV monotherapy are effective in naïve HBeAg-negative CHB patients, but further studies are needed to obtain long-term results.