Adefovir dipivoxil added to ongoing lamivudine in chronic hepatitis B with YMDD mutant hepatitis B virus

Adefovir for lamivudine-resistant hepatitis B

Adefovir, a nucleotide analog developed by John Martin, was a major breakthrough in the treatment of chronic Hepatitis B. Prior to adefovir, Hepatitis B treatment was limited to two therapeutic modalities, either interferon, which carried significant side effects and was efficacious in a minority of patients, or lamivudine which showed no durable effects with short-term use and a high rate of resistance with long-term use. Adefovir was found to be effective in suppressing viral replication and in resolving the hepatic inflammation associated with hepatitis B with only rare instances of resistance. In this article, we appreciate John Martin’s contribution to science and medicine as we review the landmark trials of adefovir that brought forth a new era of treatment of Hepatitis B.

Safety, efficacy, and pharmacokinetics of pradefovir for the treatment of chronic hepatitis B infection

BACKGROUND & AIMS

Pradefovir is a liver targeted novel prodrug of adefovir (PMEA) developed to provide higher antiviral activity with reduced systemic toxicities. This study evaluated the tolerability, pharmacokinetics, and antiviral activity of pradefovir in patients with chronic hepatitis B (CHB) virus infection.

METHODS

Non-cirrhotic, treatment-naïve subjects with CHB were divided into five groups (10 patients each) and randomized within each group in a ratio of 6:2:2 to receive an ascending dose of 30, 60, 75, 90, or 120 mg pradefovir, 10 mg adefovir dipivoxil (ADV), or 300 mg tenofovir disoproxil fumarate (TDF) once a day for 28 days.

RESULTS

A total of 51 subjects were randomized and 49 subjects completed the study. The groups were well matched and included 39 males, of whom 71% were hepatitis B e-antigen-negative with a mean hepatitis B virus (HBV) DNA level of 6.4-7.16 log10 IU/mL. No subject experienced a serious adverse event or nephrotoxicity. The most frequently reported adverse event was asymptomatic reduction in blood cholinesterase levels in the pradefovir group which recovered without any treatment about 13 ± 7 days after drug discontinuation. This adverse event was not observed in the ADV and TDF groups. The mean changes in serum HBV DNA were -2.78, -2.77, -3.08, -3.18, -3.44, -2.34, and -3.07 log10 IU/mL at 30, 60, 75, 90, and 120 mg pradefovir, 10 mg ADV and 300 mg TDF, respectively, with plateau levels reached with 60 mg pradefovir. Pradefovir and its metabolite PMEA showed linear pharmacokinetics proportional to the dose. The half-life of PMEA in the pradefovir group was 11.47-17.63 h.

CONCLUSIONS

Short-term use of pradefovir was well tolerated. A decline in HBV DNA levels was superior to TDF at higher doses of pradefovir. 30-60 mg pradefovir is recommended for CHB treatment.

CLINICAL TRIAL NUMBER

CTR20150224.

Viral quasispecies of hepatitis B virus in patients with YMDD mutation and lamivudine resistance may not predict the efficacy of lamivudine/adefovir rescue therapy

The association between hepatitis B virus (HBV) quasispecies (QS) and the efficacy of nucleos(t)ide analog therapy is currently not well defined, particularly in the case of lamivudine (LAM)/adefovir (ADV) combination rescue therapy for patients with chronic HBV infection (CHB) presenting with LAM resistance. In the present study, 16 CHB patients with the rtM204I/V mutation in the tyrosine-methionine-aspartate-aspartate motif of the C domain of the polymerase gene who switched to LAM/ADV treatment due to LAM resistance were assessed. HBV DNA was isolated from these patients and the reverse transcriptase (RT) region was sequenced. The QS heterogeneity and distribution was analyzed, the mutation sites were recorded and the phylogenetic trees were constructed. The results indicated that QS heterogeneity and distribution in the RT and S regions were not significantly different between responders (RS) and non-RS (NRS) at baseline (P>0.05), except for the higher frequency of a dominant strain in the RT region at the nucleotide level in the RS group (P=0.039). In addition, in NRS, no significant difference in QS heterogeneity or distribution in these regions was identified at six months vs. the baseline. Furthermore, although in the non-responder group the frequency of the LAM resistance-associated mutations (rtM204V/I) decreased at 6 months compared with the baseline, it did not disappear in any of the patients after six months of treatment. Analysis of individual patients did not indicate any consistent selection of specific HBV mutants during LAM/ADV rescue therapy. In conclusion, the baseline HBV QS within the RT and S regions may not be a valid predictor of the response to LAM/ADV rescue treatment in CHB patients with LAM resistance.

Efficacy of switching from adefovir to tenofovir in chronic hepatitis B patients who exhibit suboptimal responses to adefovir-based combination rescue therapy due to resistance to nucleoside analogues (SATIS study)

Background/Aims

It remains to be determined whether switching from adefovir (ADV) to tenofovir (TDF) provides better virological outcomes in patients exhibiting suboptimal responses to ADV plus nucleoside analogue (ADV+NA) therapy for NA-resistant chronic hepatitis B (CHB).

Methods

In this prospective trial, patients who showed partial responses (defined as serum hepatitis B virus [HBV] DNA >60 IU/mL) to ADV+NA therapy for NA resistance were randomly allocated to receive TDF plus NA (TDF+NA group, n=16) or to continue their current therapy (ADV+NA group, n=16). The primary end point was the proportion of patients with complete virological response (CVR, defined as serum HBV DNA <60 IU/mL) at 48 weeks.

Results

The median age was 52 years (16 men), and 28 were positive for hepatitis B e antigen (HBeAg). The baseline characteristics did not differ significantly between the two groups. The proportion with CVR was significantly higher in the TDF+NA group than in the ADV+NA group at 24 weeks (81.3% vs. 25.0%, P=0.001) and 48 weeks (87.5% vs. 37.5%, P=0.002). Furthermore, a decrease in the serum HBV DNA level of >2log₁₀ IU/mL was more likely in the TDF+NA group at both 24 and 48 weeks (68.8% vs. 56.3%, P=0.014 vs. 81.3% vs. 56.3%, P=0.001, respectively). During the follow-up, the rate of HBeAg seroconversion was higher in the TDF+NA group than the ADV+NA group (12.5% vs. 6.25%, P=0.640), as was that for the hepatitis B surface antigen (6.25% vs. 0%, P=0.080). No serious adverse events due to antiviral agents occurred.

Conclusion

In patients exhibiting suboptimal responses to ADV+NA therapy for NA-resistant CHB, switching from ADV to TDF might provide better virological outcomes.

The Management of Hepatitis B in Liver Transplant Recipients

Liver transplant (LT) is now an established indication for patients with chronic hepatitis B, mainly because of the development and use of hepatitis B immunoglobulin (HBIG) and oral antivirals for prophylaxis. The combination of low-dose HBIG and antivirals has been considered the standard prophylaxis regimen to prevent post-LT recurrence of hepatitis B. The important remaining issues are related to the long-term cost of HBIG and the risk of escape hepatitis B virus (HBV) mutants. Strategies for prevention of HBV after LT are constantly improving. With the availability of new nucleoside/nucleotide analogues, new post-LT strategies also should emerge.

Profile of HBV polymerase gene mutations during entecavir treatment in patients with chronic hepatitis B

BACKGROUND/AIMS

We investigated the efficacy of entecavir (ETV) monotherapy in 54 naïve patients and 27 lamivudine (LMV) and/or adefovir (ADV) experienced patients.

METHODS

Eighty-one chronic hepatitis B patients with a viral load above 4 log 10 copies/ml and high levels of serum alanine aminotransferase were treated with ETV 0.5mg daily. The viruses of patients were sequenced before ETV therapy and after every three months of ETV therapy.

RESULTS

Eight LAM-experienced and ADV-experienced patients emerged mutations in the ETV treatment. In one of these experienced patients, the ETV-resistant mutations were detected during ETV treatment, with the virological and the biochemical breakthrough. Two LAM-experienced and ADV-naïve patients were detected mutation during 1-2 years ETV therapy. All three LAM-naïve and ADV-experienced patients were detected mutations in the ETV treatment. Five in fifty for LAM-naïve and ADV-naïve patients showed mutations in the ETV monotherapy.

CONCLUSIONS

ETV has a high genetic barrier to resistance and the efficacy in LAM-experienced and/or ADV-experienced patients were much lower than in naïve patients.

Comparative efficacy of oral nucleotide analogues for the prophylaxis of hepatitis B virus recurrence after liver transplantation: a network meta-analysis

BACKGROUND

Prophylactic nucleos(t)ide anologues against hepatitis B virus (HBV) recurrence after liver transplantation (LT) include lamivudine, entecavir, tenofovir, adefovir. Since the most effective strategies for post-LT remain inconclusive, we aimed to compare 6 different treatment options (lamivudine, entecavir, tenofovir, adefovir, lamivudine plus adefovir, lamivudine plus tenofovir) in terms of HBV recurrence after LT using network meta-analysis.

METHODS

The search identified seventeen studies involving 6 different prophylactic regimens covering 7274 patients.

RESULTS

Compared with entecavir, lamivudine plus tenofovir (OR 2.00, 95%CI 0.02-183.29), lamivudine plus adefovir, (OR 2.83, 95%CI 0.18-33.57), tenofovir (OR 1.11, 95%CI 0.22-5.80), adefovir (OR 3.78, 95%CI 0.59-22.16), lamivudine (OR 4.62, 95%CI 1.75-11.39) were associated with an increased risk of HBV recurrence.

CONCLUSION

Entecavir resulted with the highest probability (31%) as the best prophylactic option on reducing the risk of HBV recurrence. Entecavir is the preferred oral NAs treatment compared to other five different prophylactic regimens in the prevention of HBV recurrence after LT.

Evidence-based clinical practice guidelines for liver cirrhosis 2015

The Japanese Society of Gastroenterology revised the evidence-based clinical practice guidelines for liver cirrhosis in 2015. Eighty-three clinical questions were selected, and a literature search was performed for the clinical questions with use of the MEDLINE, Cochrane, and Igaku Chuo Zasshi databases for the period between 1983 and June 2012. Manual searching of the latest important literature was added until August 2015. The guidelines were developed with use of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. This digest version in English introduces selected clinical questions and statements related to the management of liver cirrhosis and its complications. Branched-chain amino acids relieve hypoalbuminemia and hepatic encephalopathy and improve quality of life. Nucleoside analogues and peginterferon plus ribavirin combination therapy improve the prognosis of patients with hepatitis B virus related liver cirrhosis and hepatitis C related compensated liver cirrhosis, respectively, although the latter therapy may be replaced by direct-acting antivirals. For liver cirrhosis caused by primary biliary cirrhosis and active autoimmune hepatitis, urosodeoxycholic acid and steroid are recommended, respectively. The most adequate modalities for the management of variceal bleeding are the endoscopic injection sclerotherapy for esophageal varices and the balloon-occluded retrograde transvenous obliteration following endoscopic obturation with cyanoacrylate for gastric varices. Beta-blockers are useful for primary prophylaxis of esophageal variceal bleeding. The V2 receptor antagonist tolvaptan is a useful add-on therapy in careful diuretic therapy for ascites. Albumin infusion is useful for the prevention of paracentesis-induced circulatory disturbance and renal failure. In addition to disaccharides, the nonabsorbable antibiotic rifaximin is useful for the management of encephalopathy. Anticoagulation therapy is proposed for patients with acute-onset or progressive portal vein thrombosis.

Mutational analysis of reverse transcriptase and surface proteins of patients with partial virological response during mono and combination antiviral therapies in genotype D chronic hepatitis B

Introduction

The mutational pattern of chronic Hepatitis B virus (HBV) is unclear in patients who show incomplete response to antiviral therapy. The aims of this study were 1) to determine the benefit of combination therapy with adefovir dipivoxil (ADV) and Lamivudine (LAM) versus ADV or LAM alone in maintaining virological, biochemical and histological responses and 2) to investigate the patterns of mutations in the reverse transcriptase and surface proteins of HBV with LAM and/or ADF-resistant in partially-responded chronic hepatitis B (CHB) patients.

Methods

The study group consisted of 186 chronic HBV carriers who were admitted to the Tehran Hepatitis Network from 2010 to 2013. We retrospectively selected 86 patients who partially responded to different nucleoside analogue regimens. After 48 weeks of therapy, five groups of patients were defined including eight Lamivudine (LAM) Group (I), 30 Adefovir (ADV) Group (II), 16 ADV add on LAM Group (III), 32 ADV+LAM Group (IV), and 100 controls (no therapy). Reverse transcriptase (RT) and surface genes were amplified and sequenced for mutational analysis.

Results

All groups showed differences between mean values for age, gender, alanine transaminase (ALT), aspartate transaminase (AST), and HBV DNA levels groups showed significant differences than other groups (p < 0.05). The mutation frequencies for groups were I (1.7%), II (1.39%), III (2.28%), IV (2.0%), and V (0.38%). T54N, L80I/V, I91L/V, L180M, M204I/V, Q215P/S, and F221Y/S showed the highest number of mutations in all groups with different frequencies. Four new, unreported mutations were found.

Conclusion

Those patients who failed to respond in the first 48 weeks, whether they were receiving mono or combination therapy, should be tested genotypically, for the early modification of treatment.

Recent Advances in the Management of Chronic Hepatitis B Including Suppression of Hepatocellular Carcinoma by Entecavir and Interferon

At present, for adults with chronic hepatitis B virus (HBV) infection, two new analogues, entecavir (ETV) and tenofovir, are recommended as the first-line therapy by the EASL (European Association for the Study of the Liver), AASLD (American Association for the Study of Liver Diseases), and APASL (Asian Pacific Association for the Study of the Liver) guidelines. The use of pegylated interferon-α (PEG IFN-α) is recommended as the first-line therapy instead of standard IFN-α according to the above 3 guidelines. In this paper, the aim was to assess: (1) the long-term efficacy and safety as well as the resistance to ETV and tenofovir disoproxil fumarate (TDF); (2) the efficacy of PEG IFN-α; (3) the role of combination therapy with IFN plus two analogues, such as lamivudine and ETV; (4) the efficacy and safety of two analogues with cirrhosis, and (5) suppression of hepatocellular carcinoma (HCC) by ETV and IFN treatment. The results are as follows: (1) both ETV and TDF showed long-term efficacy and safety; (2) PEG IFN-α resulted in a greater decline in HBV DNA levels and a higher rate of HBeAg seroconversion; (3) combination therapy with IFN plus two analogues did not elevate the rate of sustained responses; (4) both ETV and TDF showed efficacy and safety with cirrhosis (ETV especially displayed efficacy and safety with decompensated cirrhosis), and (5) suppression of HCC was observed by ETV and IFN.

Tenofovir disoproxil fumarate has a substantial efficacy against multidrug-resistant strains of hepatitis B virus

BACKGROUND & AIMS

To evaluate the efficacy of tenofovir in chronic hepatitis B (CHB) patients with adefovir resistance (ADF-R) and suboptimal response to adefovir (ADF-S).

METHODS

Nucleos(t)ide analogue (NA)-naïve patients and patients with previous adefovir failure receiving tenofovir therapy for at least 6 months were included in the study. Biochemical and virological tests were obtained at baseline and 3-month intervals in the first year and every 6 months thereafter. The primary outcome measure was complete virological response (CVR) (HBVDNA < 20 IU/ml). CVR rates were calculated by Kaplan-Meier analysis, and a multivariate Cox proportional hazard model was generated to find out factors independently associated with CVR.

RESULTS

A total of 165 patients (118 men, mean age 42 ± 12, 64 HBeAg(+) ) were included in the study. There were 105 patients in NA-naïve, 32 patients in ADF-S and 28 patients in ADF-R groups. All patients in the ADF-R group had multidrug resistance patterns. Mean duration of tenofovir treatment was 29 ± 14 months. CVR rates in NA-naïve, ADF-S and ADF-R groups were 65% vs. 75% vs. 58% at 12th month, 77% vs. 87% vs. 79% at 24th month and 83% vs. 94% vs. 79% at 36th month respectively. According to multivariate Cox regression model, HBeAg positivity (HR = 0.56, 95%CI 0.36-0.86, P = 0.008), high baseline HBVDNA level (HR = 0.64, 95%CI 0.55-0.74, P < 0.001) and ADF-R (HR = 0.47, 95%CI 0.28-0.81, P = 0.006) were independent predictors for CVR. Seven patients encountered mild renal dysfunction and were managed by dose adjustments.

CONCLUSION

CVR rates during the follow-up show that tenofovir has a decreased, yet still potent in vivo efficacy against multidrug-resistant strains of HBV.

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

PURPOSE

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

METHODS

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

FINDINGS

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

IMPLICATIONS

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

Comparison of the efficacies of entecavir 0.5 and 1.0 mg combined with adefovir in patients with chronic hepatitis B who had failed on prior nucleos(t)ide analogue treatments

Entecavir (ETV) plus adefovir (ADV) combination therapy is one of the useful treatment option for the patients with chronic hepatitis B (CHB) who had failed on prior nucleos(t) ide analogue (NA) treatments. This study compared the efficacies of the combinations of ETV 0.5 mg plus ADV and ETV 1.0 mg plus ADV in patients who had failed on prior multiple NA treatments. This retrospective analysis included 148 consecutive patients with CHB infection in Korea (n = 37 with ETV 0.5 mg plus ADV and n = 111 with ETV 1.0 mg plus ADV). The virological and biochemical responses were compared between the two groups. The cumulative probability of viral suppression of ETV 0.5 mg plus ADV was not inferior to that of ETV 1.0 mg plus ADV (hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.38-1.08; P = 0.094). The changes in serum HBV DNA level in the ETV 0.5 mg plus ADV group were not different between the two groups over 12 months. Moreover, no significant difference was observed in acquiring ETV-resistant variants between the two groups during the treatment (HR, 0.95; P = 0.953). This study suggests the proof-of-concept that the lower dose of NA in combination with other NA might be the theoretical option for rescue combination therapy in patients with CHB who had failed on prior multiple NA treatments in order to reduce systemic exposure and possible side effects of NA.

Association between adefovir dipivoxil treatment and the risk of renal insufficiency in patients with chronic hepatitis B: A meta-analysis

Adefovir dipivoxil (ADV) is an effective antiviral drug against hepatitis B virus. The renal tolerance of ADV at the currently approved dose of 10 mg daily for the treatment of chronic hepatitis B (CHB) remains controversial. The present meta-analysis was therefore performed to evaluate the renal safety of ADV treatment in patients with CHB. Two independent investigators searched MEDLINE, Embase and China National Knowledge Infrastructure databases for eligible studies published in English or Chinese until June 1, 2014. The Peto odds ratios (Peto ORs) or the rates of each study were analyzed. Seven randomized controlled trials (RCTs), four cohort studies and six single-arm studies were identified. ADV treatment was not associated with a higher incidence of nephrotoxicity in RCTs [Peto OR, 1.781; 95% confidence interval (CI), 0.637-4.979; P=0.271] but appeared to increase nephrotoxicity significantly in cohort studies (Peto OR, 2.682; 95% CI, 1.470-4.894; P=0.001); the significant increase was further observed in CHB patients receiving long-term ADV treatment in cohort studies (Peto OR, 2.275; 95% CI, 1.127-4.593; P=0.022). The analysis based on single-arm studies showed that the rate of renal dysfunction in the ADV-treated patients was 10.6% (95% CI, 0.059-0.185); the subgroup analysis with the standard of createnine levels showed a lower rate (6.9%, 95% CI, 0.013-0.298) than those in the overall studies. In conclusion, although current evidence indicated a positive link between treatment with ADV in CHB patients and an increased risk of renal dysfunction, optimally designed studies are required for definitive conclusions.

Maintaining remission in lamivudine-resistant patients with a virological response to adefovir add-on lamivudine after stopping lamivudine therapy

BACKGROUND & AIMS

We examined the durability of the virological response after discontinuing lamivudine (LVD) in chronic hepatitis B (CHB) patients with LVD-resistant hepatitis B virus (HBV), who responded to LVD plus adefovir (ADV) combination therapy, and the outcome of switching to ADV monotherapy compared to maintaining combination therapy.

METHODS

This study enrolled 72 patients with undetectable viral loads (≤12 IU/ml) and normal alanine aminotransferase levels after ADV add-on therapy for at least 6 months in LVD-resistant CHB patients. The enrolled patients were randomly assigned to continue with LVD-ADV combination therapy or switch to ADV monotherapy (n = 36 per group). Virological rebound was defined as HBV DNA detection at more than 12 IU/ml by quantitative polymerase chain reaction determined on two consecutive measurements.

RESULTS

During 96 weeks of follow-up, 100% (36/36) of the patients in the LVD-ADV combination maintained group had persistently undetectable HBV DNA, compared with 94.4% (34/36) patients in the ADV monotherapy switched group. These two patients had undetectable HBV DNA after switching back to LVD-ADV combination therapy. There were no significant differences in the HBsAg levels between the two treatment groups during the 96-week follow-up period.

CONCLUSIONS

In our study, switching to ADV monotherapy resulted in sustained HBV DNA suppression in 94.4% of the patients for 96 weeks. Prior complete viral suppression with LVD-ADV combination therapy conferred a significant advantage in patients who switched to ADV monotherapy. LVD may be discontinued in patients who show a complete virological response to LVD-ADV combination therapy for at least 6 months.

Long-term results of liver transplantation for over 60 years old patients with hepatitis B virus-related end-stage liver disease

BACKGROUND

Hepatitis B virus (HBV)-related end-stage liver disease is the leading indication for liver transplantation in China, but long-term results of liver transplantation in patients aged over 60 years are not clear. The present study was to reveal the natural history of liver recipients with hepatitis B older than 60 years.

METHODS

The recipients who had received liver transplantation between December 2003 and December 2005 were divided into two groups: those equal or older than 60 years (older group, n=60) and those younger than 60 years (younger group, n=305). Risk factors for poor long-term outcome in patients aged over 60 years were also analyzed.

RESULTS

Except for age and preexisting chronic disease (P<0.05), no significant differences were observed in perioperative characteristics between the two groups. There was also no significant difference in HBV and hepatocellular carcinoma recurrence (P>0.05). The actuarial 1-, 3-, 5- and 8-year survival rates were 81.6%, 71.6%, 66.7% and 63.3% respectively for the older group vs 84.9%, 77.7%, 70.8% and 65.6% for the younger group (P>0.05). Multivariate analyses showed that pre-liver transplant renal insufficiency was a risk factor for poor outcome in the older group (odds ratio=3.615, P=0.014).

CONCLUSIONS

Liver transplantation is safe and feasible for patients with HBV-related end-stage liver disease aged over 60 years. Older patients with renal insufficiency should undergo transplantation earlier than younger patients.

Long-term outcomes of two rescue therapies in lamivudine-refractory patients with chronic hepatitis B: combined lamivudine and adefovir, and 1-mg entecavir

BACKGROUND/AIMS

Adefovir (ADV) and lamivudine (LAM) combination therapy (ADV+LAM) has been a useful option for patients with LAM-resistant (LAM-r) chronic hepatitis B (CHB). However, the long-term outcomes of LAM+ADV and 1-mg entecavir (ETV) rescue therapies have still been limited. The aim of this study was to determine the long-term outcomes of these two rescue therapies.

METHODS

Sixty patients with LAM-r CHB underwent rescue therapy with LAM+ADV (n=36) or 1-mg ETV (n=24). We determined the duration of rescue therapy, timing and type of mutation, undetectable serum hepatitis B virus (HBV) DNA by PCR (lower limitation of detection, < 140 copies/mL), biochemical response (alanine aminotransferase < 40 IU/mL), and the incidence of hepatitis B virus e antigen (HBeAg) seroconversion and virologic breakthrough.

RESULTS

Baseline characteristics did not differ between the two therapy groups. The duration of rescue therapy was 56 months (range, 14-100 months) in the ADV+LAM group and 42 months (range, 12-73 months) in the ETV group (P=0.036). The cumulative rates of HBV DNA undetectability and HBeAg seroconversion up to 6 years were 88.6% and 43.0%, respectively, in the ADV+LAM group, and 45.8% and 31.8% in the ETV group. The rate of virologic breakthrough and resistance was 14.4% in the ADV+LAM group and 71.9% in the ETV group (P=0.001).

CONCLUSIONS

Combination of LAM and ADV therapy for up to 6 years achieved modest rates of virological suppression and resistance. ETV is not an optimal therapy because the risk of viral breakthrough to ETV increases over time.

Rescue therapy with adefovir in decompensated liver cirrhosis patients with lamivudine-resistant hepatitis B virus

Background/Aims

Adefovir dipivoxil (ADV) is a nucleotide analogue that is effective against lamivudine-resistant hepatitis B virus (HBV). The aim of this study was to determine the long-term clinical outcomes after ADV rescue therapy in decompensated patients infected with lamivudine-resistant HBV.

Methods

In total, 128 patients with a decompensated state and lamivudine-resistant HBV were treated with ADV at a dosage of 10 mg/day for a median of 33 months in this multicenter cohort study.

Results

Following ADV treatment, 86 (72.3%) of 119 patients experienced a decrease in Child-Pugh score of at least 2 points, and the overall end-stage liver disease score decreased from 16±5 to 14±10 (mean ± SD, P<0.001) during the follow-up period. With ADV treatment, 67 patients (56.3%) had undetectable serum HBV DNA (detection limit, 0.5 pg/mL). Virologic breakthrough occurred in 38 patients (36.1%) and 9 patients had a suboptimal ADV response. The overall survival rate was 89.9% (107/119), and a suboptimal response to ADV treatment was associated with both no improvement in Child-Pugh score (≥2 points; P=0.001) and high mortality following ADV rescue therapy (P=0.012).

Conclusions

Three years of ADV treatment was effective and safe in decompensated patients with lamivudine-resistant HBV.

Effect of prophylactic versus preemptive lamivudine treatment and tenofovir on HBsAg+ kidney transplant recipients

OBJECTIVES

Chronic hepatitis B virus infection remains a clinical problem for HBsAg (+) kidney transplant recipients. Lamivudine is the approved treatment; however, there are contrary views about optimal initiation. In case of resistance, novel nucleoside analogs should be considered but experience is limited.

MATERIALS AND METHODS

The study was a retrospective cohort study that included 58 HBsAg (+) kidney transplant recipients. Medical records were reviewed for nucleoside analogs, viral replication, and graft/hepatic functions. Prophylactic and preemptive lamivudine modalities were compared to reveal optimal initiation. Additionally, novel nucleoside analogs were evaluated for safety and efficacy.

RESULTS

The graft/patient survival rates for HBsAg (+) recipients were the same as those of hepatitis-free recipients (P = .18). Prophylactic group had 24 and the preemptive had 34 patients. In the prophylactic group, there were fewer hepatic dysfunctions (12.5% vs. 30%, P = .12), viral breakthroughs (16% vs. 32%, P = .17) and elevated alanine aminotransferase concentrations (37% vs. 52%, P = .24), however these did not reach statistical significance. Progressive hepatic dysfunction was observed in 5 patients. Treatment was altered to tenofovir (n = 4) and adefovir (n = 1), and adequate virologic/biochemical response was achieved. These nucleoside analogs were almost as safe as lamivudine, as there were no significant differences among proteinuria (4740 ± 9480 vs 1250 ± 430 mg/L; P = .60) and estimated glomerular filtration rate (1.23 ± 0.37 vs 1.10 ± 0.35 mL/s; P = .33) CONCLUSIONS: Lamivudine is an efficient means of providing comparable graft/patient survival with hepatitis-free kidney transplant recipients. The prophylactic initiation of lamivudine may be better in preventing hepatic dysfunction. Tenofovir can be an effective and safe treatment for lamivudine-resistant kidney transplant recipients.

Long-term efficacy and emergence of multidrug resistance in patients with lamivudine-refractory chronic hepatitis B treated by combination therapy with adefovir plus lamivudine

BACKGROUND

Few studies have investigated the emergence of multidrug resistance to adefovir dipivoxil (ADV) plus lamivudine (LAM) combination therapy for patients with LAM-refractory chronic hepatitis B (CHB). In this retrospective study, we investigated the long-term clinical course of these patients with or without multidrug resistance mutations.

METHODS

We analyzed 406 Japanese patients with LAM-refractory CHB treated with combination therapy with follow-up for a median of 5.4 (0.5-9.5) years. Multidrug resistance of hepatitis B virus (HBV) DNA was analyzed using direct sequencing or cloning methods at baseline and viral breakthrough or insufficient decline during combination therapy.

RESULTS

Ratio of patients with undetectable serum HBV DNA levels (<2.6 log copies/mL) during combination therapy was 63, 72, 75, 79, 82, 80 and 85 % at years 1 through 7, respectively. Substitutions associated with multidrug resistance were identified in 11 patients (2.7 %) at baseline, and in 12 patients (3 %) during therapy. HBV DNA levels of patients with rtA181S mutation at baseline and emergence of rtA181T + rtN236T double mutation or a wide variety of mutations during combination therapy could not be suppressed. Moreover, using ultra-deep sequencing, rtA181T/V mutations were detected at baseline in 7 of 10 patients with emergent multidrug resistance during combination therapy, although 6 of these 7 patients had very low frequency (<1 %) variants.

CONCLUSION

Long-term ADV plus LAM combination therapy is effective in LAM-refractory patients. However, HBV DNA levels of the patients with multidrug resistance at baseline or during combination therapy sometimes could not achieve complete suppression or were re-elevated after a decrease.

The impact of the hepatitis B virus polymerase rtA181T mutation on replication and drug resistance is potentially affected by overlapping changes in surface gene

The emergence of drug-resistant hepatitis B virus (HBV) is a major problem for antiviral treatment in chronic hepatitis B infection. In this study, we analyzed the evolution of drug-resistant mutations and characterized the effects of the rtA181T and rtI233V mutations on viral replication and drug resistance. We performed a clonal analysis of the HBV polymerase gene from serum samples during viral breakthrough treated with antiviral agents. A series of mutant clones containing rtA181T and/or rtI233V mutations were constructed and determined the effect of these mutations on the replication ability and drug resistance. An in vitro study revealed that the effect of the rtA181T mutation on viral replication and drug resistance is dependent on the mutations in the overlapping surface gene. Compared to the rtA181T surface missense mutation (rtA181T/sW172S), the introduction of rtA181T surface nonsense mutation (rtA181T/sW172*) resulted in decreased viral replication and increased drug resistance. Complementation assay revealed that the truncated PreS1 is responsible for reduced replication of rtA181T/sW172* mutant. Moreover, the rtA181T/sW172* mutant exhibited a defect in viral particle secretion. The rtI233V mutation that emerged during adefovir therapy reduced viral replication and conferred resistance to adefovir. Our data suggest that the impact of the rtA181T mutation on replication and drug resistance differs based on the mutation status of the corresponding surface gene. The rtI233V mutation also affects replication ability and drug resistance. This observation suggests the need for genotypic analysis of overlapping surface genes to manage antiviral drug resistance if clinical isolates harbor the rtA181T mutation.

IMPORTANCE

The emergence of drug-resistant HBV that are no longer susceptible to nucleos(t)ide analogues is a major problem for antiviral treatment in chronic hepatitis B infection. Among drug-resistant mutations, the single rtA181T mutation is known to confer cross-resistance to antiviral drugs. This mutation causes intermediate or reduced susceptibility to tenofovir. Moreover, the clinical occurrence of the rtA181T mutation during antiviral therapy is also high. Our study revealed that the effect of the rtA181T mutation on viral replication and drug resistance is dependent on the mutations in the overlapping surface gene. This observation suggests the need for genotypic analysis of overlapping surface genes to manage antiviral drug resistance if clinical isolates harbor the rtA181T mutation. We believe that our study will not only extend the understanding of the drug resistance mechanism, but it will also ultimately provide new treatment options for patients with multidrug resistant HBV.

Partial virological response to adefovir add-on lamivudine rescue therapy in patients with lamivudine-resistant chronic hepatitis B

BACKGROUND/AIMS

In patients with lamivudine (LAM)-resistant chronic hepatitis B (CHB) receiving adefovir (ADV) add-on LAM therapy, insufficient viral suppression or the appearance of additional ADV resistance has remained unresolved. This study determined the partial virological response (PVR) criteria to predict a virological response (VR) at week 96 in these patients.

METHODS

96 patients with LAM-resistant CHB (ADV add-on LAM therapy >2 years) were analyzed. For predicting VR at week 96, the area under the receiver operating characteristic curve values at different time points were compared to establish the optimal time point, and the maximal Youden index was calculated to determine the optimal cut-off hepatitis B virus (HBV) DNA level.

RESULTS

50 (52.1%) patients achieved VR at 2 years after ADV add-on LAM therapy. The optimal PVR criteria were determined to be HBV DNA 500 IU/ml at week 48. 44 (45.8%) patients who met optimal PVR criteria showed a significantly higher risk for detectable HBV DNA levels at week 96 than those with a favorable VR (HBV DNA <500 IU/ml) at week 48.

CONCLUSIONS

This study suggested optimal PVR criteria in patients with LAM-resistant CHB receiving ADV add-on LAM therapy. Modification of the antiviral agent regimen should be considered if the serum HBV DNA level exceeds 500 IU/ml at week 48.

Then and now: The progress in hepatitis B treatment over the past 20 years

The ultimate goals of treating chronic hepatitis B (CHB) is prevention of hepatocellular carcinoma (HCC) and hepatic decompensation. Since the advent of effective antiviral drugs that appeared during the past two decades, considerable advances have been made not only in controlling hepatitis B virus (HBV) infection, but also in preventing and reducing the incidence of liver cirrhosis and HCC. Furthermore, several recent studies have suggested the possibility of reducing the incidence of recurrent or new HCC in patients even after they have developed HCC. Currently, six medications are available for HBV treatment including, interferon and five nucleoside/nucleotide analogues. In this review, we will examine the antiviral drugs and the progresses that have been made with antiviral treatments in the field of CHB.

Adefovir dipivoxil in the treatment of chronic hepatitis B virus infection

Adefovir dipivoxil (Hepsera, Gilead Sciences) is a prodrug of adefovir, with potent antiviral activity against hepatitis B virus. Adefovir dipivoxil therapy, 10 mg daily for 48 weeks, is effective in hepatitis B e antigen-positive and -negative chronic hepatitis B. In hepatitis B e antigen-negative chronic hepatitis B, adefovir dipivoxil was recently found to maintain its efficacy even after 3 years of therapy. Adefovir dipivoxil is effective in patients with compensated or decompensated chronic viral B liver disease, and in pre- and post-transplant hepatitis B virus patients who develop resistance to lamivudine (Epivir, GlaxoSmithKline). It is well-tolerated and safe even after the third year of long-term therapy, and is associated with low rates of viral resistance. All these characteristics make adefovir dipivoxil an important drug for the treatment of hepatitis B virus infection and an excellent candidate for long-term maintenance therapy in chronic viral B liver disease.

Too much of a good thing? When to stop catch-up vaccination

During the 20th century, deaths from a range of serious infectious diseases decreased dramatically due to the development of safe and effective vaccines. However, infant immunization coverage has increased only marginally since the 1960s, and many people remain susceptible to vaccine-preventable diseases. "Catch-up vaccination" for age groups beyond infancy can be an attractive and effective means of immunizing people who were missed earlier. However, as newborn vaccination rates increase, catch-up vaccination becomes less attractive: the number of susceptible people decreases, so the cost to find and vaccinate each unvaccinated person may increase; in addition, the number of infected individuals decreases, so each unvaccinated person faces a lower risk of infection. This article presents a general framework for determining the optimal time to discontinue a catch-up vaccination program. We use a cost-effectiveness framework: we consider the cost per quality-adjusted life year gained of catch-up vaccination efforts as a function of newborn immunization rates over time and consequent disease prevalence and incidence. We illustrate our results with the example of hepatitis B catch-up vaccination in China. We contrast results from a dynamic modeling approach with an approach that ignores the impact of vaccination on future disease incidence. The latter approach is likely to be simpler for decision makers to understand and implement because of lower data requirements.

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.

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

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

Antivirais incorporados no Brasil para hepatite B cronica: analise de custo-efetividade

OBJETIVO Avaliar o custo-efetividade de diferentes tratamentos medicamentosos para hepatite B crônica entre pacientes adultos. MÉTODOS Utilizando modelo de Markov, construiu-se coorte hipotética de 40 anos para pacientes HBeAg-positivo ou HBeAg-negativo. Foram comparados os usos de adefovir, entecavir, tenofovir e lamivudina (com terapia de resgate em caso de resistência viral) para tratamento de pacientes adultos com hepatite B crônica, virgens de tratamento, com elevados níveis de alanina aminotransferase, sem evidência de cirrose e sem coinfecção por HIV. Valores para custo e efeito foram obtidos da literatura. A medida do efeito foi expressa em anos de vida ganhos (AVG). Taxa de desconto de 5% foi aplicada. Análise de sensibilidade univariada foi conduzida para avaliar incertezas do modelo. RESULTADOS O tratamento inicial com entecavir ou tenofovir apresentou melhores resultados clínicos. As menores razões custo-efetividade foram de entecavir para pacientes HBeAg-positivo (R$ 4.010,84/AVG) e lamivudina para pacientes HBeAg-negativo (R$ 6.205,08/AVG). Para pacientes HBeAg-negativo, a razão custo-efetividade incremental de entecavir (R$ 14.101,05/AVG) está abaixo do limiar recomendado pela Organização Mundial da Saúde. Análise de sensibilidade mostrou que variação nos custos dos medicamentos pode tornar tenofovir alternativa custo-efetiva tanto para pacientes HBeAg-positivo quanto para HBeAg-negativo. CONCLUSÕES Entecavir é alternativa recomendada para iniciar o tratamento de pacientes com hepatite B crônica no Brasil. Contudo, se houver redução no custo de tenofovir, esta pode se tornar alternativa mais custo-efetiva.

Treatment of patients with HBV-related decompensated cirrhosis and liver transplanted patients

Antiviral therapy using newer nucleos(t)ide analogs with lower resistance rates could suppress hepatitis B virus (HBV) replication, improve liver function in patients with compensated or decompensated cirrhosis, delay or obviate liver transplantation in some patients, and reduce the risk of HBV recurrence. Some form of HBV prophylaxis needs to be continued indefinitely posttransplant. However, in patients with a low-risk of HBV recurrence it is possible to discontinue hepatitis B immunoglobulins and maintain long-term nucleos(t)ide analog therapy. Currently, treatment of posttransplantation hepatitis B is a less important clinical problem than it was historically because effective antiviral therapies exist to rescue patients who failed initial prophylaxis.

The efficacy of adefovir plus entecavir combination therapy in patients with chronic hepatitis B refractory to both lamivudine and adefovir

BACKGROUND

The efficacy of adefovir (ADV) plus entecavir (ETV) combination in patients with chronic hepatitis B (CHB) who developed multidrug refractoriness had not been fully evaluated. We aimed to evaluate the efficacy of ADV plus ETV as compared to that of lamivudine (LAM) plus ADV in the patients with antiviral refractoriness to sequential LAM monotherapy and then ADV monotherapy.

METHODS

Twenty-seven patients were treated with a combination of ADV plus ETV and 63 patients were treated with a combination of LAM plus ADV. The virological and biochemical parameters were compared between the two groups, retrospectively.

RESULTS

Treatment with a combination of ADV plus ETV produced significantly superior virological response than that of a combination of LAM plus ADV. At 12 months, the HBV DNA declined more in the ADV plus ETV group than in the LAM plus ADV (-4.52 ± 1.956 vs. -2.65 ± 1.723 log 10 IU/mL; p = 0.001). The rate of a complete response at 12 months was greater in the ADV plus ETV group than that in the LAM plus ADV group (63.16 vs. 14.81 %, p < 0.001).

CONCLUSION

In the patients with CHB refractory to both LAM and ADV, the response to ADV plus ETV was significantly superior compared to that of the LAM plus ADV in suppressing HBV DNA. The result indicates that ADV plus ETV can be used as a bridging therapy in the patients with refractoriness to both LAM and ADV, especially in the areas where tenofovir is not yet available.

Antiviral efficacies of currently available rescue therapies for multidrug-resistant chronic hepatitis B

Background/Aims

The incidence of multidrug-resistant (MDR) chronic hepatitis B (CHB) during sequential lamivudine (LAM) and adefovir dipivoxil (ADV) treatment is increasing. We investigated the antiviral efficacies of various rescue regimens in patients who failed sequential LAM-ADV treatment.

Methods

Forty-eight patients (83.3% of whom were HBeAg-positive) who failed sequential LAM-ADV treatment were treated with one of the following regimens: entecavir (ETV) (1 mg) monotherapy (n=16), LAM+ADV combination therapy (n=20), or ETV (1 mg)+ADV combination therapy (n=12). All patients had confirmed genotypic resistance to both LAM and ADV and were evaluated every 12 weeks.

Results

The baseline characteristics and treatment duration did not differ significantly among the study groups. During the treatment period (median duration: 100 weeks), the decline of serum HBV DNA from baseline tended to be greatest in the ETV+ADV group at all-time points (week 48: -2.55 log₁₀ IU/mL, week 96: -4.27 log₁₀ IU/mL), but the difference was not statistically significant. The ETV+ADV group also tended to have higher virologic response rates at 96 weeks compared to the ETV monotherapy or LAM+ADV groups (40.0% vs. 20.0% or 20.0%, P=0.656), and less virologic breakthrough was observed compared to the ETV monotherapy or LAM+ADV groups (8.3% vs. 37.5% or 30.0%; P=0.219), but again, the differences were not statistically significant. HBeAg loss occurred in one patient in the ETV+ADV group, in two in the ETV monotherapy group, and in none of the LAM+ADV group. The safety profiles were similar in each arm.

Conclusions

There was a nonsignificant tendency toward better antiviral efficacy with ETV+ADV combination therapy compared to LAM+ADV combination therapy and ETV monotherapy for MDR CHB in Korea, where tenofovir is not yet available.

Combination of lamivudine and adefovir without hepatitis B immune globulin is safe and effective prophylaxis against hepatitis B virus recurrence in hepatitis B surface antigen-positive liver transplant candidates

Without effective prophylaxis, liver transplantation for hepatitis B virus (HBV)-related liver disease is frequently complicated by severe and rapidly progressive HBV recurrence. Combination prophylaxis with hepatitis B immune globulin (HBIG) and lamivudine (LAM) reduces long-term recurrence rates below 10%; however, HBIG is costly and inconvenient to administer. We, therefore, conducted a multicenter, prospective study of outcomes with an HBIG-sparing regimen of LAM plus adefovir dipivoxil (ADV) initiated at the time of listing for liver transplantation and continued after transplantation. Twenty-six patients were recruited into this study at the time of listing for transplantation, and 20 subsequently underwent transplantation. Twelve of the 26 patients had LAM exposure before the study baseline, but none had LAM resistance. The median HBV viral load before the institution of antiviral therapy was approximately 4.0 log(10) IU/mL (range=2.3-7.5 log(10) IU/mL). To the 20 patients who underwent transplantation, 800 IU of intramuscular HBIG was given immediately after transplantation and daily for 7 days only (total HBIG dose=6400 IU). All transplant patients remained alive without HBV recurrence (they were negative for hepatitis B surface antigen, and HBV DNA was undetectable) after a median follow-up of 57 months after transplantation (range=27-83 months). The median serum creatinine level in these patients rose from 81 to 119 μmol/L over the course of the study. No patient required dose reduction or cessation. After the completion of this prospective study, the regimen was modified so that no perioperative HBIG was administered if the pretransplant serum HBV DNA level was suppressed below 3 log(10) IU/mL. Another 28 patients with HBV-related liver disease underwent transplantation (18 without HBIG). All remained alive and well without HBV recurrence after a median follow-up of 22 months after transplantation (range=10-58 months). In conclusion, a combination of LAM and ADV initiated at the time of wait listing provides safe and effective protection against recurrent HBV infection without the high costs and inconvenience associated with long-term HBIG therapy.

The effect of pretransplantation lamivudine resistance on the prognosis of liver transplant recipients

BACKGROUND

Since the introduction of lamivudine to treat chronic hepatitis B (CHB), the prevalence of lamivudine resistance is increasing among orthotopic liver transplant (OLT) candidates in Korea.

OBJECTIVE

The purpose of this study was to evaluate the effect of pre-OLT lamivudine-resistance on the post-OLT prognosis of recipients.

MATERIAL AND METHODS

Consecutive OLT recipient at a single tertiary care center (n = 8) between September 1999 and August 2009 were tested preoperatively for genotypic lamivudine resistance. We compared overall survival as well as incidences of graft failure, recurrent hepatitis, and hepatocellular carcinoma (HCC) between patients with (n = 35) versus without (n = 46) lamivudine-resistance.

RESULTS

Mortality occurred in 2 resistant and 3 nonresistant individuals. The occurrences of graft failure, recurrent hepatitis, and HCC were 1, 2, and 2 cases, respectively, in the resistance group versus 2, 2, and 2 cases, respectively, in the nonresistance cohort. Univariate analysis showed no significant difference in survival, graft failure, HCC occurrence, and recurrent hepatitis.

CONCLUSIONS

Our results indicated that pre-OLT lamivudine-resistance did not significantly affect the post-OLT prognosis. Thus, lamivudine-resistance may not be a barrier when considering OLT in patients with underlying CHB as a therapeutic modality, if it is treated with appropriate antiviral agents.

Treatment strategies using adefovir dipivoxil for individuals with lamivudine-resistant chronic hepatitis B

AIM: To investigate retrospectively the long-term efficacy of various treatment strategies using adefovir dipivoxil (adefovir) in patients with lamivudine-resistant chronic hepatitis B.

METHODS: We included 154 consecutive patients in two treatment groups: the “add-on” group (n = 79), in which adefovir was added to ongoing lamivudine treatment due to lamivudine resistance, and the “switch/combination” group (n = 75), in which lamivudine was first switched to adefovir and then re-added later as needed. The “switch/combination” group was then divided into two subgroups depending on whether participants followed (group A, n = 30) or violated (group B, n = 45) a proposed treatment strategy that determined whether to add lamivudine based on the serum hepatitis B virus (HBV) DNA levels (< 60 IU/mL or not) after 6 mo of treatment (roadmap concept).

RESULTS: The cumulative probability of virologic response (HBV DNA < 60 IU/mL) was higher in group A than in the “add-on” group and in group B (P < 0.001). In contrast, the cumulative probability of virologic breakthrough was lower in the “add-on” group than in group B (P = 0.002). Furthermore, the risk of virologic breakthrough in the multivariate analysis was significantly lower in the “add-on” group than in group A (hazard ratio = 0.096; 95%CI, 0.015-0.629; P = 0.015).

CONCLUSION: The selective combination of adefovir with lamivudine based upon early treatment responses increased the odds of virologic breakthrough relative to the use of uniform combination therapy from the beginning of treatment.

Long-term outcomes of add-on adefovir dipivoxil therapy to ongoing lamivudine in patients with lamivudine-resistant chronic hepatitis B

AIM

  Add-on adefovir dipivoxil (ADV) therapy has been a standard rescue treatment for patients with lamivudine (LAM)-resistant chronic hepatitis B, but the overall benefits of long-term add-on ADV therapy are still limited. The aim of this study was to evaluate the long-term efficiency of add-on ADV treatment and to explore predictive factors associated with it.

METHODS

  A total of 158 patients with LAM-resistant chronic hepatitis B were included in this retrospective, multicenter, nationwide study in Japan. After confirming LAM resistance, ADV was added to LAM treatment. Three types of events were considered as outcomes: virological response, hepatitis B e antigen (HBeAg) clearance and alanine aminotransferase (ALT) normalization. Virological response was defined as serum hepatitis B virus (HBV) DNA levels of less than 3 log copies/mL. Baseline factors contributing to these outcomes were examined by univariate and multivariate analyses.

RESULTS

  The median total duration of ADV treatment was 41 months (range, 6-84). The rate of virological response was 90.8% at 4 years of treatment; HBeAg clearance and ALT normalization were achieved by 34.0% and 82.7%, respectively, at the end of follow up. Each outcome had different predictive factors: baseline HBV DNA and albumin level were predictive factors for virological response, history of interferon therapy and ALT level for HBeAg clearance, and sex and baseline albumin level for ALT normalization.

CONCLUSION

  Long-term add-on ADV treatment was highly effective in LAM-resistant chronic hepatitis B patients in terms of virological and biochemical responses. Lower HBV replication and lower albumin level at baseline led to better outcomes.

Virologic responses to add-on adefovir dipivoxil treatment versus entecavir monotherapy in children with lamivudine-resistant chronic hepatitis B

PURPOSE

The aim of the study was to compare the virologic response to adefovir (ADV) add-on therapy with switching to entecavir (ETV) monotherapy in children and adolescents with chronic hepatitis B (CHB) who have developed lamivudine (LAM) resistance during LAM treatment.

METHODS

Twenty-seven consecutive patients with CHB who had developed LAM resistance during LAM treatment were included. Of these 27 patients, 8 patients were treated with the addition of ADV to ongoing LAM and 8 patients were treated by switching to ETV monotherapy and each of these 16 patients were compared with the 11 patients who were treated by switching to ADV alone, as a historical control. Therapeutic responses to treatment were evaluated at 12, 24, 36, and 48 weeks from the initiation of therapy by measuring the decrement of hepatitis B virus (HBV)-DNA titers.

RESULTS

The therapeutic period for HBV-DNA titer decrement (>2  log(10) IU/mL) was significantly shorter in both the LAM+ADV group and the ETV group than in the ADV group (P = 0.008); however, there was no significant difference between the LAM+ADV group and the ETV group. The rate of virologic response, defined as decrement in HBV-DNA titer to undetectable levels at 24 weeks, was significantly higher in both the LAM+ADV group and the ETV group than in the ADV group (P = 0.029).

CONCLUSIONS

Both the LAM+ADV combination therapy and ETV monotherapy exhibited significantly more effective virologic responses compared to the ADV monotherapy in children and adolescents with LAM-resistant CHB, although there was no significant difference between the LAM+ADV group and the ETV group.

Viral response at 6 months is associated with treatment outcome of adefovir add-on therapy for lamivudine-resistance

BACKGROUND AND AIM

  Adefovir add-on therapy is recommended for patients infected with lamivudine-resistant hepatitis B virus (HBV). We aimed to describe the long-term treatment outcome and predictors for good response of adefovir add-on therapy.

METHODS

A total of 559 chronic hepatitis B (CHB) patients who had been treated for at least 12 months with adefovir add-on therapy due to resistance to lamivudine were retrospectively included. Complete virologic response (CVR) was defined as serum HBV DNA <9IU/mL. Viral responses at 6months were classified as PCR negativity, partial virologic response (PVR, HBV DNA <2000 IU/mL), or inadequate virologic response (IVR, HBV DNA≥2000IU/mL).

RESULTS

The median duration of follow-up was 31.5 months (range, 12-56). The cumulative probabilities of CVR during adefovir add-on therapy were 58%, 70%, 78%, and 80% at 12, 24, 36, and 43 months, respectively. The cumulative rates of resistance to adefovir were 0.4%, 0.8%, and 3.1% at 12, 24, and 36 months, respectively. The only baseline factor associated with CVR (hazard ratio 0.83, 95% confidence interval 0.62-0.91, P≤0.001) and resistance to adefovir (hazard ratio 1.925, 95% confidence interval 1.13-3.30, P=0.017) was serum HBV DNA level. Comparison of the cumulative rates of CVR and resistance to adefovir according to viral response at 6months showed significant differences among the three groups (P<0.0001 and P= 0.0005, respectively).

CONCLUSIONS

Pre-treatment HBV DNA level and viral response at 6months is associated with treatment outcome for adefovir-add on therapy in lamivudine resistance.

Lamivudine treatment enabling right hepatectomy for hepatocellular carcinoma in decompensated cirrhosis

A 69-year-old man was admitted to our hospital in October 2003, for further examination of two liver tumors. He was diagnosed with hepatocellular carcinoma (HCC) arising from decompensated hepatitis B virus (HBV)-related cirrhosis. Long-term lamivudine administration improved liver function dramatically despite repeated treatment for HCC. His Child-Pugh score was 9 points at start of lamivudine treatment, improving to 5 points after 1 year. His indocyanine green at 15 min after injection test score was 48% before lamivudine treatment, improving to 22% after 2 years and to 5% after 4 years. Radiofrequency ablation controlled the HCC foci and maintained his liver function. In April 2009, abdominal computed tomography revealed a tumor thrombus in the right portal vein. Since his indocyanine green test results had improved to less than 10%, we performed a right hepatectomy, which was successful. To our knowledge, there have been no documented reports of patients undergoing successful right hepatectomy for HCC arising from decompensated cirrhosis. The findings observed in our patient indicate the importance of nucleoside analogs for treating HBV-related HCC.

Virologic response is not durable after adefovir discontinuation in lamivudine-resistant chronic hepatitis B patients

Background/Aims

We investigated the durability of the biochemical and virologic responses after adefovir (ADV) discontinuation in lamivudine-resistant (LMV-R) chronic hepatitis B (CHB) patients, and the outcomes of ADV discontinuation compared to that of ADV maintenance.

Methods

The indication for ADV treatment cessation was an undetectable level of hepatitis B virus (HBV) DNA documented on two occasions at least 6 months apart. All patients received additional ADV for at least 12 months after the confirmation of undetectable HBV DNA (Cobas TaqMan PCR assay, <70 copies/mL). Of 36 patients who had a sufficient ADV therapeutic effect, 19 discontinued ADV treatment, while the others maintained it. A virologic rebound was arbitrarily defined as the redetection of HBV DNA at a level higher than 10⁵ copies/mL.

Results

In the ADV discontinuation group, ADV treatment and additional therapy were administered for medians of 33 months (range, 12-47 months) and 18 months, respectively. The patients were followed for a median of 12 months (range, 3-30 months) after ADV cessation. During that period, 18 of 19 patients (95%) experienced viral relapse. Viral rebound was observed in six patients (32%). However, 12 of 18 patients (67%) exhibited serum HBV DNA levels of less than 10⁵ copies/mL. Biochemical relapses were observed in four of the six patients with viral rebound. In the ADV maintenance group, patients were treated for a median of 53 months (range, 31-85 months), and 9 patients (53%) experienced viral breakthrough.

Conclusions

During short-term follow-up after ADV discontinuation, most patients (95%) exhibited viral relapse, whereas and viral breakthrough occurred in about half of patients (53%) maintained on ADV therapy. Therefore, the durability of virologic response after ADV discontinuation in LMV-R patients was unsatisfactory. In addition, and viral breakthrough was not infrequent in the ADV continuation group.

Adefovir dipivoxil in chronic hepatitis B: history and current uses

INTRODUCTION

The nucleotide analogue adefovir dipivoxil (ADV) was approved in 2002 for the treatment of chronic infection with hepatitis B virus (HBV), in both hepatitis B e antigen (HBeAg)-positive and -negative patients. ADV 10 mg daily has been associated with improved liver histology, decreased levels of HBV DNA and alanine aminotransferase (ALT), and seroconversion of HBeAg.

AREAS COVERED

This paper reviews the use of ADV as a first-line treatment for chronic hepatitis B and as an add-on therapy in chronic HBV-infected patients with lamivudine resistance. In the years since its launch, clinical resistance to ADV has emerged, and tenofovir and entecavir have shown greater efficacy in reducing viral load.

EXPERT OPINION

Many patients who started antiviral therapy with ADV (either as monotherapy or in combination with lamivudine) remain on this agent because they have undetectable viremia, but its future use will probably diminish because of the availability of more potent drugs. ADV is generally well tolerated, though the 10 mg dose is associated with low risk of nephrotoxicity.

Long-term effect of lamivudine treatment on the incidence of hepatocellular carcinoma in patients with hepatitis B virus infection

BACKGROUND

Nucleotide analogues have recently been approved for the treatment of patients with hepatitis B virus (HBV) infection. However, it is still controversial whether the decrease of HBV-DNA amount induced by treatment with nucleotide analogues can reduce the risk of hepatocellular carcinoma (HCC) development in HBV patients.

METHODS

A total of 293 HBV patients without HCC who were treated with lamivudine (LAM) were enrolled in a multicenter trial. The incidence of HCC was examined after the start of LAM therapy, and the risk factors for liver carcinogenesis were analyzed. The mean follow-up period was 67.6 ± 27.4 months.

RESULTS

On multivariate analysis for HCC development in all patients, age ≥50 years, platelet count <14.0 × 10(4)/mm(3), cirrhosis, and median HBV-DNA levels of ≥4.0 log copies/ml during LAM treatment were significant risk factors. The cumulative carcinogenesis rate at 5 years was 3% in patients with chronic hepatitis and 30% in those with cirrhosis. For the chronic hepatitis patients, the log-rank test showed the significant risk factors related to HCC development to be age ≥50 years, platelet count <14.0 × 10(4)/mm(3), and hepatitis B e antigen negativity, but median HBV-DNA levels of <4.0 log copies/ml (maintained viral response, MVR) did not significantly suppress the development of HCC. In cirrhosis patients, however, the attainment of MVR during LAM treatment was revealed to reduce the risk of HCC development.

CONCLUSIONS

These results suggest that the incidence of HCC in HBV patients with cirrhosis can be reduced in those with an MVR induced by consecutive LAM treatment.

De novo combination therapy with lamivudine and adefovir dipivoxil in chronic hepatitis B patients

AIM: To investigate the appropriate time for combination therapy in HBeAg positive chronic hepatitis B (CHB) patients with decompensated cirrhosis.

METHODS: Thirty HBeAg positive CHB patients with decompensated cirrhosis were enrolled in the study. All of the patients were given 48 wk combination therapy with lamivudine (LAM) and adefovir dipivoxil (ADV). Briefly, 10 patients were given the de novo combination therapy with LAM and ADV, whereas the other 20 patients received ADV in addition to LAM after hepatitis B virus (HBV) genetic mutation.

RESULTS: Serum alanine aminotransferase and total bilirubin were both improved in the two groups at 4, 12, 24 and 48 wk after treatment. Serum albumin was also improved at 24 and 48 wk after combination therapy in both groups. The serum HBV DNA level was still detectable in every patient in the two groups at 4 and 12 wk after combination treatment. However, in the de novo combination group, serum HBV DNA levels in 4 (40%) and 9 (90%) patients was decreased to below 1×10³ copies/mL at 24 and 48 wk after the combination treatment, respectively. In parallel, serum HBV DNA levels in 2 (20%) and 8 (40%) patients in the add-on combination group became undetectable at 24 and 48 wk after combination treatment, respectively. Furthermore, 6 (60%) patients in the de novo combination group achieved HBeAg seroconversion after 48 wk treatment, whereas only 4 (20%) patients in the add-on combination group achieved seroconversion. Child-Pugh score of patients in the de novo combination group was better than that of patients in the add-on combination group after 48 wk treatment. Moreover, patients in the de novo combination group had a significantly decreased serum creatinine level and elevated red blood cell counts.

CONCLUSION: De novo combination therapy with LAM and ADV was better than add-on combination therapy in terms of Child-Pugh score, virus inhibition and renal function.

HBV DNA level at 24 weeks is the best predictor of virological response to adefovir add-on therapy in patients with lamivudine resistance

BACKGROUND

The aim of this study was to investigate the relationship between HBV DNA levels at baseline and on-treatment and the virological response at 96 weeks after adefovir add-on therapy in chronic hepatitis B (CHB) patients with lamivudine resistance.

METHODS

Lamivudine and adefovir combination therapy was administered to 122 CHB patients for >24 months.

RESULTS

Virological response (HBV DNA negativity) was achieved in 53 (43.3%) and 62 patients (50.8%) at 48 and 96 weeks, respectively. The receiver operating characteristic curve analysis showed that the HBV DNA level at week 24 had a greater power (area under the receiver operating characteristic curve 0.978; 95% CI 0.949, 1.000; P<0.001) to predict the virological response at week 96 of treatment than did the pre-treatment HBV DNA level (area under the receiver operating characteristic curve 0.771; 95% CI 0.640, 0.902; P<0.001). The best cutoff value for the HBV DNA level, at week 24, for the prediction of the virological response at week 96 was 200 IU/ml (3 log(10) copies/ml), with a sensitivity and specificity of 90.3% and 95.0%, respectively. Using this time frame and cutoff value, 56 (90.3%) out of 62 patients that had a virological response at 96 weeks had <200 IU/ml HBV DNA at 24 weeks.

CONCLUSIONS

Although the HBV DNA level at baseline is often used to predict the antiviral potency of lamivudine and adefovir combination treatment in CHB patients with lamivudine resistance, the results of this study suggest that the HBV DNA level at 24 weeks is a better marker for the virological response.

A novel model for evaluating the risk of hepatitis B recurrence after liver transplantation

BACKGROUND

Hepatitis B virus (HBV) recurrence is a major risk factor affecting the long-term survival of recipients for liver transplantation (LTx). Therefore, a model that can assess this risk before transplantation is highly desirable.

METHODS

One hundred and eighty-five consecutive liver transplant recipients because of HBV-related end-stage liver diseases were selected. Their perioperative laboratory examination results, treatment protocol and the status of HBV recurrence were the primary parameters used to assess their risk of post-transplant HBV recurrence. A model that may be generally used to evaluate the risk of post-transplant HBV recurrence was thus established. A cohort for further validation and a cross-validation were designed.

RESULTS

After a follow-up time of 26.0 ± 10.8 months, the overall HBV recurrence rate was 8.6%. The 1-, 2- and 3-year cumulative survival rates were 98.5, 89.2 and 83.4% respectively. By correlation with the pretransplant presence of hepatocelluar carcinoma (HCC), serum HBV DNA level and status of antiviral treatment (AVT), the risk assessment model can be summarized using the following equation: RISK=-4.378 + 1.493 × HCC + 1.286 × DNA - 2.426 × AVT. The HBV recurrence rate and survival were found to be significantly different between the recipients with risk scores ≤-2.8 and >-2.8. The model was well validated in this work.

CONCLUSIONS

Pretransplant HBV DNA level, presence of HCC, AVT status and post-transplant viral mutation were identified as the major risk factors associated with HBV recurrence after LTx. A novel model incorporating these factors could effectively evaluate the risk of post-transplant HBV recurrence before transplantation.

Entecavir treatment in HBV-related decompensated cirrhosis

Entecavir monotherapy has now been evaluated in patients with hepatitis B virus (HBV)-related decompensated cirrhosis. Entecavir achieves 1-year HBV DNA undetectability rates in up to 90% of treatment-naive patients in this setting without any case of resistance. Entecavir was generally safe and well tolerated. Lactic acidosis was described almost exclusively in very advanced liver disease (MELD score >20) and usually subsided with drug discontinuation. After 1 year of entecavir therapy, the Child–Pugh score improved by ≥2 points in up to 50% of patients and decreased mean MELD score by >2 points. The 1-year survival rates were 84–91%, mainly associated with baseline Child–Pugh or MELD scores. In conclusion, entecavir monotherapy is an excellent treatment option for treatment-naive patients with HBV-related decompensated cirrhosis.

Current status of liver transplantation for hepatitis B virus

The management of hepatitis B in liver transplantation has evolved significantly over the past 2 decades. Introduction of hepatitis B immune globulin and subsequently nucleos(t)ide analogues has revolutionized transplantation for hepatitis B virus (HBV), increasing survival for patients transplanted for this indication. With the availability of new and potent antivirals for HBV, the need for liver transplant should continue to decrease in the coming years. Moreover, the newer antivirals with high resistance barriers will allow effective long-term viral prophylaxis and therefore, prevention of recurrence.