Extended lamivudine retreatment for chronic hepatitis B: maintenance of viral suppression after discontinuation of therapy

Effect of iron saturation of bovine lactoferrin on the inhibition of hepatitis B virus in vitro

Background

Hepatitis B virus (HBV) infection poses a major public health problem worldwide. Bovine lactoferrin (bLf) is a natural product that can inhibit HBV, but the effect of iron saturation on its resistance to HBV is unknown.

Aims

The purpose of this study is to investigate the impact of iron saturation of bLf against HBV.

Methods

HepG2 cells were cultured in DMEM high glucose containing 10% inactivated fetal calf serum, at 37 °C, in 5% CO2. MTT method was used to detect the cytotoxicity of bLf to HepG2 cells. Apo-bLf and holo-bLf were prepared from bLf. Iron saturation of these proteins was determined by atomic absorption spectrophotometry. Non-cytotoxic concentrations of candidate proteins were used in anti-HBV tests. Fluorescent quantitative polymerase chain reaction was used to detect HBV-DNA.

Results

The TC50 and TC0of bLf were 54.570 mg/ml and 1.997 mg/ml, respectively. The iron saturation of bLf, apo-bLf and holo-bLf were 10.29%, 8.42% and 85.32%, respectively. In this study, four non-cytotoxic concentrations of candidate proteins (1.5, 1.0, 0.5, and 0.1 mg/ml, respectively) were used to inhibit HBV in HepG2 cells. The results showed that 1.5 mg/ml bLf and 0.1 mg/ml holo-bLf effectively impaired the HBV-DNA amplification in HBV-infected HepG2 cells (P < 0.05). However, apo-bLf, and Fe3+ did not show the anti-HBV effects.

Conclusion

A total of 1.5 mg/ml bLf and 0.1 mg/ml holo-bLf could inhibit HBV-DNA in HepG2 cells. Complete bLf structure, appropriate concentration and iron saturation of bLf are necessary conditions for anti-HBV effects.

Hemodialysis-Associated Infections

Hemodialysis patients are at increased risk of infections, which are common adverse events among this patient population. We review factors contributing to infections among hemodialysis patients and epidemiology of common infections and outbreaks, including bloodstream infections, vascular access infections, and infections caused by bloodborne pathogens. Recommendations for prevention are discussed with emphasis on essential infection control practices for hemodialysis settings.

Potential Efficacy of Pegylated Interferon-α and a Nucleos(t)ide Analogue as Combination Therapy for HBeAg-Positive Chronic Hepatitis B

Background/Aims

Despite the potent suppression of the hepatitis B virus with modern antiviral agents, only a minority of HBeAg-positive patients achieve hepatitis B e antigen seroconversion. We aimed to explore the potential efficacy of combination therapy consisting of pegylated interferon (p-IFN) and an oral antiviral agent in patients with HBeAg-positive chronic hepatitis B.

Methods

The treatment protocol consisted of p-IFN-α-2a at 180 μg/wk for 48 weeks, with either entecavir or tenofovir added 8 weeks after the initiation of p-IFN and continued for at least 6 months after HBe seroconversion was achieved.

Results

To date, 10 patients have been treated under the protocol (eight adults, mean age 36±8 years; two adolescents, aged 12 and 16 years). All eight adult patients experienced loss of HBeAg at a mean of 72.3±66.9 weeks, including six patients who also developed anti-HBe and one patient who had HBs seroconversion. Although both adolescents remain on therapy, one adolescent had HBs seroconversion without HBe seroconversion. A total of nine of our 10 patients experienced a favorable serological transition.

Conclusions

The combination of p-IFN and a modern oral antiviral agent may be more effective than monotherapy with either class of agent in the treatment of HBeAg-positive chronic hepatitis B patients.

Long-term lamivudine therapy in chronic hepatitis B

BACKGROUND

One to 5 years of therapy of chronic hepatitis B with oral nucleoside analogues result in significant clinical improvements, but effects of more prolonged therapy are not well defined.

AIM

To describe outcomes of chronic hepatitis B with long-term lamivudine therapy.

METHODS

Forty-two patients with chronic hepatitis B treated with lamivudine were followed for 3.2-19.5 (median = 16.1) years. Therapy was switched to other agents (n = 16) if patients developed lamivudine resistance and relapse of disease.

RESULTS

Among 22 HBeAg-positive patients, 17 (77%) became HBeAg negative, of whom 5 (23%) subsequently cleared HBsAg. Among 20 HBeAg-negative patients, 10 (50%) cleared HBsAg. The time to HBsAg clearance ranged from 0.9 to 16.8 (median = 9.3) years. Lamivudine resistance arose in 24 patients (57%) of whom 6 (25%) lost HBsAg. HBsAg clearance was not always accompanied by seroconversion; anti-HBs appearing concurrently in only five patients (33%). Nevertheless, HBsAg loss allowed for stopping therapy in all patients, none re-developing HBsAg or suffering relapse; all having normal alanine aminotransferase levels and no (n = 13) or unquantifiable HBV DNA levels (n = 2) when last seen. In contrast, seven of 27 patients (26%) who remained HBsAg-positive died of liver disease or liver cancer or underwent liver transplantation, all of whom had cirrhosis.

CONCLUSIONS

Long-term viral suppression with nucleoside analogues leads to HBsAg loss in a substantial proportion of patients, particularly if HBeAg-negative. Serious outcomes during the first 10-20 years of treatment occur largely among patients with pre-existing cirrhosis who do not clear HBsAg with therapy.

Clinical outcomes and predictors for relapse after cessation of oral antiviral treatment in chronic hepatitis B patients

BACKGROUND

Little is known about stopping rules of nucelos(t)ide analog (NA) treatment for chronic hepatitis B (CHB).

METHODS

A total of 113 consecutive patients with CHB (45 HBeAg-positive and 68 HBeAg-negative CHB patients), who met the cessation criteria of NA treatment as per the Asian-Pacific Association for the Study of the Liver (APASL) guideline, were enrolled in this prospective cohort study. The primary endpoint was to evaluate virological relapse (VR) rate within 1 year, which was defined as reappearance of hepatitis B virus (HBV)-DNA > 2000 IU/mL after cessation of NA treatment. In this cohort, entecavir was used in 81 (71.7 %) and lamivudine in 32 (28.3 %) patients.

RESULTS

Within 1 year after NA treatment, VR occurred in 26 (57.8 %) HBeAg-positive patients and in 37 (54.4 %) HBeAg-negative patients. In univariate and subsequent multivariate analysis, age > 40 years [odds ratio (OR) 10.959; 95 % confidence interval (CI) 2.211-54.320; P = 0.003) and a pre-treatment HBV DNA level >2000,000 IU/mL (OR 9.285; 95 % CI 1.545-55.795; P = 0.036) were identified as independent risk factors for VR in HBeAg-positive patients, and age > 40 years (OR 6.690; 95 % CI 1.314-34.057; P = 0.022) and an end-of-treatment HBcrAg level >3.7 log IU/mL (OR 3.751; 95 % CI 1.187-11.856; P = 0.024) were identified in HBeAg-negative patients. During follow up, neither hepatic decompensation nor hepatocellular carcinoma (HCC) occurred, and HBV DNA suppression was achieved in all patients who received antiviral re-treatment.

CONCLUSION

Our data suggested that the APASL stopping rule could be applied if a candidate was properly selected using individual risk factors. However, regular monitoring should be performed after cessation of NA treatment and long-term outcomes need to be evaluated further.

Lamivudine Resistance and Precore Variants in Iranian Patients With Chronic Hepatitis B: Correlation With Virological and Clinical Features

Background:

Long-term lamivudine therapy, despite its initial effectiveness against hepatitis B virus (HBV), is associated with the emergence of drug resistance mutations in polymerase protein.

Objectives:

The aim of the present study was to determine the prevalence of precore and lamivudine drug resistance mutations in lamivudine treated patients with chronic B hepatitis.

Patients and Methods:

Sequential sera were obtained from 88 chronic HBV carriers who received lamivudine for more than 24 months. Polymerase and precore regions were directly sequenced for these groups: I (before treatment), II, and III (12 and 24 months after treatment, respectively).

Results:

All patients (100%) were contained genotype D, subtype ayw2. One (1.1%), 12 (13.6%), and 22 (25%) members of groups I, II, and III had the replacement of either isoleucine or valine instead of methionine in tyrosine-methionine-aspartate-aspartate (YMDD) motif, respectively. The frequency of mutations from 0 time point to 12 and 24 months showed that there was an increasing trend between sequential samples (P < 0.001). In group I, 31 (35.2%); II, 36 (41.0%) and III, 41 (46.6%) members had the precore stop codon mutations. The frequency of mutations from 0 time point to 12 and 24 months showed that there was an ascending trend between sequential samples. Indeed, frequency of precore stop codon was significantly increased with the passage of time (P < 0.001).

Conclusions:

Presence of drug resistance mutations among the patients was significant. Precore mutations were common amongst Iranian HBV chronic carriers under lamivudine therapy and these mutations were accompanied by clinical relapse.

Seroclearance of Hbsag in Chronic Hepatitis B Virus Patients on Lamivudine Therapy: A 10 Year Experience

Introduction:

The aim of this study was to determine hepatitis B surface antigen (HBsAg) seroclearance rate among patients treated with lamivudine at a specialized tertiary care referral hospital in Tehran, Iran.

Methods:

All patients on lamivudine (biovudin®) therapy at a dose of 100 mg/day, who showed seroclearnace between March 2001 and September 2011 were recruited. The main evaluation parameters were duration of HBsAg seroclearance and duration of HBsAg seroconversion. Serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were evaluated using standard methods. HBsAg seroclearance was defined as two consecutive negative serums HBsAg at least 6 months apart, whereas HBsAg seroconversion was defined as the disappearance of serum HBsAg and the presence of anti-HBs for >6 months.

Results:

A total of 203 chronic HBV patients treated with lamivudine at a dose of 100 mg/day were included in the study. HBsAg seroclearance and seroconversion were observed in 11 patients after the initiation of the lamivudine therapy. Overall, in lamivudine responder patients, the mean time to HBsAg seroclearance was 26.90±10.93 months (range: 12-48 months). Furthermore, the responders showed seroconversion after a mean time of 26.90±11.08 months from the initiation of lamivudine therapy. When comparing the characteristics of those who have responded to lamivudine and those who have not responded, baseline HBV-DNA levels was significantly lower in responder than non responder patients (p<0.001). Meantime, there was no difference in age, sex, baseline ALT, AST and liver biopsy score between lamivudine responder and lamivudine non-responder patients.

Conclusion:

Despite introduction of tenofovir and entecavir as first line treatment for chronic HBV infection, lamivudine remains to be a low cost, safe and effective drug for HBsAg seroclearnace.

Successful withdrawal of antiviral treatment in kidney transplant recipients with chronic hepatitis B viral infection

BACKGROUND

The optimal duration of antiviral therapy for kidney transplant recipients (KTR) with chronic hepatitis B virus (HBV) infection remains unclear. We reported the long-term outcomes after withdrawal of antiviral agent in KTR with chronic HBV infection.

METHODS

We retrospectively investigated the hepatitis B surface antigen (HBsAg)-positive KTR with antiviral agents between January 2002 and January 2012. Antiviral treatments were withdrawn in patients who met all of the following 7 criteria: (i) no clinical and histologic evidence of cirrhosis, (ii) normal liver biochemistry, (iii) negative for both HBV DNA and hepatitis B envelope antigen (HBeAg), (iv) no resistance to antiviral agent, (v) antiviral therapy > 9 months, (vi) maintenance dosage of immunosuppressant for > 3 months, and (vii) no history of acute rejection during recent 6 months. All patients were followed regularly at approximately 3-6 months for liver enzyme, viral markers, and HBV DNA level after antiviral withdrawal.

RESULTS

Among a total of 445 KTR, 14 HBsAg-positive patients were included in this study. Antiviral agents were used, with lamivudine in 11 patients, and with adefovir, entecavir, and telbivudine in 3 patients, respectively. Discontinuation of antiviral agent was attempted in 6 (42.9%) of 14 patients who satisfied the criteria. The median duration of antiviral therapy before withdrawal was 14.3 months (range, 9-24 months). Four (66.7%) of 6 patients were successfully withdrawn and remained negative for HBV DNA for a median 60.5 months (range, 47-82 months). The baseline HBV DNA level was not related to maintenance of remission after withdrawal. Two reactivated patients resumed antiviral treatment immediately, with subsequent normalization of HBV DNA. During the follow-up, 1 patient developed hepatocellular carcinoma; however, no patient death or graft failure was reported for all HBsAg-positive KTR.

CONCLUSIONS

Antiviral therapy can be discontinued successfully and safely in selected KTR with chronic HBV infection, after complete suppression of HBV and sufficient duration of antiviral therapy.

Durability of viral response after off-treatment in HBeAg positive chronic hepatitis B

AIM: To evaluate the durability in hepatitis B e antigen (HBeAg) positive chronic hepatitis B patients who discontinued antiviral treatment.

METHODS: A total of 48 HBeAg positive chronic hepatitis B patients who were administered nucleoside analogues and maintained virological response for ≥ 6 mo [hepatitis B virus (HBV) DNA < 300 copies/mL and HBeAg seroconversion] before cessation of treatment were enrolled between February 2007 and January 2010. The criteria for the cessation of the antiviral treatment were defined as follows: (1) achievement of virological response; and (2) duration of consolidation therapy (≥ 6 mo). After treatment cessation, the patients were followed up at 3-6 mo intervals. The primary endpoint was serologic and virologic recurrence rates after withdrawal of antiviral treatment. Serologic recurrence was defined as reappearance of HBeAg positivity after HBeAg seroconversion. Virologic recurrence was defined as an increase in HBV-DNA level > 10⁴ copies/mL after HBeAg seroconversion with previously undetectable HBV-DNA level.

RESULTS: During the median follow-up period of 18.2 mo (range: 5.1-47.5 mo) after cessation of antiviral treatment, the cumulative serological recurrence rate was 15 % at 12 mo. The median duration between the cessation of antiviral treatment and serologic recurrence was 7.2 mo (range: 1.2-10.9 mo). Of the 48 patients with HBeAg positive chronic hepatitis, 20 (41.6%) showed virological recurrence. The cumulative virologic recurrence rates at 12 mo after discontinuing the antiviral agent were 41%. The median duration between off-treatment and virologic recurrence was 7.6 mo (range: 4.3-27.1 mo). The mean age of the virological recurrence group was older than that of the non-recurrence group (46.7 ± 12.1 years vs 38.8 ± 12.7 years, respectively; P = 0.022). Age (> 40 years) and the duration of consolidation treatment (≥ 15 mo) were significant predictive factors for offtreatment durability in the multivariate analysis [P = 0.049, relative risk (RR) 0.31, 95% CI (0.096-0.998) and P = 0.005, RR 11.29, 95% CI (2.054-65.12), respectively]. Patients with age (≤ 40 years) who received consolidation treatment (≥ 15 mo) significantly showed durability in HBeAg positive chronic hepatitis B patients (P = 0.014). These results suggest that additional treatment for more than 15 mo after HBeAg seroconversion in patients who are ≤ 40 years old may be beneficial in providing a sustained virological response.

CONCLUSION: Our data suggest that HBeAg seroconversion is an imperfect end point in antiviral treatment. Long-term consolidation treatment (≥ 15 mo) in younger patients is important for producing better prognosis in HBeAg positive chronic hepatitis B.

Clinical course of chronic hepatitis B patients who were off-treated after lamivudine treatment: analysis of 138 consecutive patients

BACKGROUND/AIMS

Little is known about the long-term outcome of chronic hepatitis B (CHB) patients who discontinued antiviral therapy. We intended to analyze the long-term outcome of CHB patients who discontinued lamivudine therapy and to evaluate predictors for post-treatment outcome.

MATERIAL/METHODS

From 2007 to 2008, 138 lamivudine off-treated CHB patients with alanine aminotransferase normalization were consecutively enrolled. Post-treatment virologic relapse, biochemical breakthrough, hepatitis flare, and retreatment results were retrospectively analyzed.

RESULTS

Among 138 patients, 102 were initially HBeAg-positive at the start of lamivudine treatment. Virologic relapse, biochemical breakthrough, and hepatitis flare were observed in 45.2, 52.9, and 12.7% of HBeAg-positive and 29.4, 30.6, and 8.3% of HBeAg-negative patients during the median follow-up of 28 and 30 months, respectively. The cumulative virologic relapse and biochemical breakthrough rates were significantly lower in patients with HBV DNA <50 copies/mL than 50-104 copies/mL at lamivudine cessation. Hepatitis flare was observed in 4.8 and 11.8% of HBeAg-positive and HBeAg-negative patients with HBV DNA <50copies/mL, respectively. Thirty-eight among 138 patients received retreatment and most of them achieved biochemical (37/38) and virologic response (35/38) within 1 year of retreatment. Undetectable serum HBV DNA (<50 copies/mL) and young age at lamivudine cessation were inversely associated with virologic relapse. Undetectable HBV DNA at cessation, female, and initial HBeAg-negative were inversely associated with biochemical breakthrough.

CONCLUSIONS

Post-treatment virologic relapse and biochemical breakthrough incidence were low in patients who achieved undetectable viral titer at lamivudine cessation. Retreatment after biochemical breakthrough or virologic relapse was safe and effective. Intermittent antiviral therapy might be cautiously considered in appropriately selected CHB patients.

Evaluation of single and combination therapies with tenofovir disoproxil fumarate and emtricitabine in vitro and in a robust mouse model supporting high levels of hepatitis B virus replication

Next-generation therapies for chronic hepatitis B virus (HBV) infection will involve combinations of established and/or experimental drugs. The current study investigated the in vitro and in vivo efficacy of tenofovir disoproxil fumarate (TDF) and/or emtricitabine [(-)-FTC] alone and in combination therapy for HBV infection utilizing the HepAD38 system (human hepatoblastoma cells transfected with HBV). Cellular pharmacology studies demonstrated increased levels of (-)-FTC triphosphate with coincubation of increasing concentrations of TDF, while (-)-FTC had no effect on intracellular tenofovir (TFV) diphosphate levels. Quantification of extracellular HBV by real-time PCR from hepatocytes demonstrated the anti-HBV activity with TDF, (-)-FTC, and their combination. Combination of (-)-FTC with TDF or TFV (ratio, 1:1) had a weighted average combination index of 0.7 for both combination sets, indicating synergistic antiviral effects. No cytotoxic effects were observed with any regimens. Using an in vivo murine model which develops robust HBV viremia in nude mice subcutaneously injected with HepAD38 cells, TDF (33 to 300 mg/kg of body weight/day) suppressed virus replication for up to 10 days posttreatment. At 300 mg/kg/day, (-)-FTC strongly suppressed virus titers to up to 14 days posttreatment. Combination therapy (33 mg/kg/day each drug) sustained suppression of virus titer/ml serum (<1 log(10) unit from pretreatment levels) at 14 days posttreatment, while single-drug treatments yielded virus titers 1.5 to 2 log units above the initial virus titers. There was no difference in mean alanine aminotransferase values or mean wet tumor weights for any of the groups, suggesting a lack of drug toxicity. TDF-(-)-FTC combination therapy provides more effective HBV suppression than therapy with each drug alone.

rtL180M mutation of hepatitis B virus is closely associated with frequent virological resistance to adefovir dipivoxil therapy

BACKGROUND AND AIM

We intended to investigate the effects of pre-existing mutations at reverse transcriptase region of hepatitis B virus (HBV) on the occurrence of virological breakthrough (VB) to adefovir dipivoxil (ADV) in patients with lamivudine (LAM)-resistant chronic hepatitis B (CHB).

METHODS

Ninety-seven patients with LAM-resistant CHB were treated with ADV at a dose of 10 mg daily, and were followed for a median period of 13 months. Just before the initiation of ADV therapy, the whole length of reverse transcriptase region of serum HBV-DNA was sequenced using direct sequencing.

RESULTS

All patients had genotype C HBV and mutations in the YMDD motif, specifically, YIDD (65%), YVDD (28%), or both (7%). The rtL180M and rtL80V/I mutations were identified in 68% and 69%, respectively. The cumulative probability of VB was 19% and 27% at 1 and 2 years, respectively. There was no difference in the occurrence of VB with regard to types of YMDD mutation or rtL80V/I. However, interestingly, patients carrying rtL180M experienced VB during ADV monotherapy more frequently than those not carrying rtL180M (2-year cumulative probability of VB: 37% vs 3% at 2 years, P < 0.01). On multivariate Cox proportional hazards analysis, rtL180M (hazard ratio [HR]: 8.62, 95% confidence interval: 1.08-69.09, P = 0.042) and decrease in HBV-DNA for 1 year of treatment (HR: 0.69, 95% CI: 0.51-0.95, P = 0.024) are independently associated with VB.

CONCLUSIONS

The rtL180M mutation of HBV, as well as a small decrease in HBV-DNA after 1 year of treatment might be closely associated with frequent occurrence of virological resistance to ADV in patients with LAM-resistant CHB.

Antiviral resistance mutations potentiate HBV surface antigen-induced transcription of hfgl2 prothrombinase gene

Antiviral resistance mutations in the hepatitis B virus (HBV) polymerase (pol) gene have been demonstrated to play an important role in the progression of liver disease and the development of hepatocellular carcinoma. The HBV pol gene overlaps the S gene encoding surface antigen (HBsAg). Previous studies from our laboratory have shown that HBV core protein (HBc) and X protein (HBx), but not HBV S protein (HBs), promote hfgl2 prothrombinase transcription. To investigate whether the nucleotide (nucleoside)-induced resistant mutations of HBs potentiate transcription of hfgl2 prothrombinase gene, we generated two mutant HB expression constructs harboring rtM204V/sI195M or rtM204I/sW196L mutations. Two mutant expression plasmids were co-transfected with hfgl2 promoter luciferase-reporter plasmids and β-galactosidase plasmid in CHO cells and HepG2 cells, respectively. Luciferase assay showed that the rtM204I/V mutant HBs could activate the transcription of hfgl2 promoter compared with the wild type HBs. Site-directed mutagenesis and further experiment (co-transfection) demonstrated that transcription factor Ets translocated to its cognate cis-element in the hfgl2 promoter. The results show that mutated HBs caused by antiviral drug resistance induce transcription of the hfgl2 gene dependent on the transcription factor Ets.

The underlying mechanisms for the "simultaneous HBsAg and anti-HBs serological profile"

The course of HBV infection is determined by the interplay between viral replication via HBV protein production and the host's immune response. Therefore, the diagnosis of infection in clinical practice is established by the serological detection of HBV protein products as well as antibodies produced by the host. Although the serological findings for assessing the clinical course of infection are already well established, the expression of viral proteins and the dynamics of antibody production may vary during the natural course of infection. This causes the HBV infection to be occasionally associated with the presence of unusual serologic profiles, which can lead to doubts in the interpretation of results and mistaken serological diagnosis. The simultaneous detection of HBsAg and anti-HBs in the blood stream comprises an atypical serological profile, somewhat incoherent, whose significance can be complicated to establish. Outlined in this article are some immunological and molecular mechanisms which could justify the existence of this profile in which there is a great laboratorial and clinical interest.

Tenofovir and entecavir are the most effective antiviral agents for chronic hepatitis B: a systematic review and Bayesian meta-analyses

BACKGROUND & AIMS

The relative efficacies of licensed antiviral therapies for treatment-naive chronic hepatitis B (CHB) infection in randomized controlled trials have not been determined. We evaluated the relative efficacies of the first 12 months of CHB treatments.

METHODS

Drugs evaluated were lamivudine, pegylated interferon, adefovir, entecavir, telbivudine, and tenofovir, as monotherapies and combination therapies, in treatment-naive individuals. Databases were searched for randomized controlled trials of the first 12 months of therapy in hepatitis B e antigen (HBeAg)-positive and/or HBeAg-negative patients with CHB published in English before October 31, 2009. Bayesian mixed treatment comparisons were used to calculate the odds ratios, including 95% credible intervals and predicted probabilities of surrogate outcomes to determine the relative effects of each treatment.

RESULTS

In HBeAg-positive patients, tenofovir was most effective in inducing undetectable levels of HBV DNA (predicted probability, 88%), normalization of alanine aminotransferase (ALT) levels (66%), HBeAg seroconversion (20%), and hepatitis B surface antigen loss (5%); it ranked third in histologic improvement of the liver (53%). Entecavir was most effective in improving liver histology (56%), second for inducing undetectable levels of HBV DNA (61%) and normalization of ALT levels (70%), and third in loss of hepatitis B surface antigen (1%). In HBeAg-negative patients, tenofovir was the most effective in inducing undetectable levels of HBV DNA (94%) and improving liver histology (65%); it ranked second for normalization of ALT levels (73%).

CONCLUSIONS

In the first year of treatment for CHB, tenofovir and entecavir are the most potent oral antiviral agents for HBeAg-positive patients; tenofovir is most effective for HBeAg-negative patients.

Novel mutation in YMDD motif and direct neighbourhood in a child with chronic HBV-infection and clinical lamivudine and adefovir resistance - a scholarly case

CONTEXT

Chronic HBV infection is a major cause of hepatocellular carcinoma (HCC) which meanwhile has become the 5th most reason for a fatal outcome of cancer. Worldwide, approximately 350 million people are chronically HBV infected and as such of risk to develop HCC, of those an estimated high rate of children. Treatment of chronic infection is sufficient to reduce the rate of HCC but the rate of sustained virological response remains to low, not at least due to emergence of resistant virus strains. Less is known on HBV infection in children despite the extremely high rate of chronicity.

OBJECTIVE, DESIGN, SETTING, AND PATIENT

The case of a nine years old male with a 6 year history of chronic HBV infection, of those 5 years with antiviral treatment is described.

INTERVENTIONS AND MAIN OUTCOME MEASURE(S)

Before our lab was consulted, the patient was unsuccessfully treated with interferon, an obscure drug named Hepon, which should activate antiviral immune response, and Lamivudine, the latter most likely becoming ineffective due to the mergence of resistant subpopulations (rtL180 M, rtV207 M, two strains with stop codons at position rt188 and rt198, rtM204V (YVDD), rtM204K (YKDD)). Replacement of Lamivudine by adefovir displayed no advantage despite the lack of resistance mutations, thus no decrease in viremia was observed under adefovir treatment.

RESULTS AND CONCLUSIONS

Novel mutations in the YMDD motif and its direct neighbourhood were observed, both being compatible with Lamivudine resistance. No mutations were found that are associated with ADF resistance. Both, the clinical course of treatment and the genotypic resistance profile emphasize the need for systematic analyses of the HBV resistance mechanisms and structured therapy concept also for children chronically infected with HBV.

Extended lamivudine consolidation therapy in hepatitis B e antigen-positive chronic hepatitis B patients improves sustained hepatitis B e antigen seroconversion

OBJECTIVES

Longer lamivudine (LAM) consolidation therapy after hepatitis B e antigen (HBeAg) seroconversion has been demonstrated to reduce the cumulative relapse rate. However, the optimal interval of LAM consolidation therapy remains controversial. We evaluated the post-treatment durability of LAM-induced HBeAg seroconversion and the length of LAM consolidation therapy required to maintain sustained HBeAg seroconversion.

MATERIAL AND METHODS

This retrospective study included 401 naive HBeAg-positive chronic hepatitis B patients who were treated with LAM 100 mg daily for at least 24 weeks (range 24-258 weeks). Among them, 124 patients who achieved a complete response (HBeAg seroconversion, alanine aminotransferase normalization, hepatitis B virus DNA < 200 copies/ml) at the end of LAM therapy were followed up for at least 48 weeks (range 48-350 weeks).

RESULTS

Of the 124 complete responders, 42 (33.87%) achieved a sustained response (persistent response >or= 48 weeks). However, the cumulative relapse rates at 48 and 96 weeks post-treatment were 54.03% and 68.4%, respectively. Multivariate analysis revealed pretreatment age <or= 34 years [hazard ratio (HR) 2.25; 95% confidence interval (CI) 1.40-3.62; p < 0.001] and LAM consolidation therapy >or= 48 weeks (HR 2.44; 95% CI 1.35-4.40; p = 0.003) to be independent factors for predicting a sustained response.

CONCLUSIONS

LAM-induced HBeAg seroconversion is not durable in Taiwan. However, a duration of LAM consolidation therapy > 48 weeks may be favorable for maintaining durable HBeAg seroconversion.

Lamivudine maintenance beyond one year after HBeAg seroconversion is a major factor for sustained virologic response in HBeAg-positive chronic hepatitis B

The reported durability of virologic response after successful lamivudine monotherapy is variable, and the question remains as to whether virologic responses can be maintained over an extended follow-up period. The aim of this study was to investigate posttreatment durability, the optimal duration of additional treatment after HBeAg clearance or seroconversion, and determinants for sustained virologic response (SVR) following lamivudine monotherapy in patients with HBeAg-positive chronic hepatitis B (CHB). From January 1999 to August 2004, 178 Korean patients with HBeAg-positive CHB were treated with lamivudine and achieved complete responses, defined as a loss of serum HBeAg and hepatitis B virus DNA, and alanine aminotransferase normalization. The mean duration of lamivudine monotherapy was 26 months (range, 12-77). SVR was maintained in 138 patients (77.5%). Host and viral factors were compared between 138 patients with SVR and 40 patients whose response was not sustained. The cumulative relapse rates increased from 15.9% at 1 year to 30.2% at 5 years, with a mean time to relapse after cessation of lamivudine of 12 months (range, 7-42). Most relapses occurred within 2 years after discontinuation of lamivudine (33/40, 82.5%). On multivariate analysis, age <or=40 years and additional treatment for more than 12 months after HBeAg clearance or seroconversion were independent factors for SVR.

CONCLUSION

The lamivudine-induced virologic response was durable in patients under 40 years old and those receiving lamivudine for more than 12 months after HBeAg clearance or seroconversion. Age and additional treatment were major predictive factors for SVR.

New scoring system for predicting relapse after lamivudine-induced hepatitis B e-antigen loss in chronic hepatitis B patients

AIM

In endemic areas of hepatitis B virus (HBV) infection, lamivudine-induced hepatitis B e-antigen (HBeAg) loss is not durable. We developed a scoring system to predict the relapse after lamivudine-induced HBeAg loss.

METHODS

Of 93 HBeAg-positive chronic hepatitis B patients receiving lamivudine therapy, we studied the 30 patients who achieved HBeAg loss. Qualitative polymerase chain reaction assays for HBV DNA were performed after HBeAg loss; if results were negative on two consecutive occasions, lamivudine treatment was stopped. Serum HBV DNA levels at the time of HBeAg loss were determined using stored serum by the Cobas Amplicor HBV Monitor Kit.

RESULTS

Cumulative relapse rates were 44%, 55.8% and 59.8%, after 1, 2 and 5 years, respectively. Univariate analysis showed that the risk factors for relapse were age (>/= 30 years), HBV DNA level (>/= 60 IU/mL) at the time of HBeAg loss and liver cirrhosis. Independent risk factors for relapse were age (odds ratio [OR], 4.3; 95% confidence interval [CI], 1.2-17.6) and serum HBV DNA level at the time of HBeAg loss (OR, 5.1; 95% CI, 1.3-21.6). We developed a scoring system based on these independent risk factors. No relapse was observed for patients with a risk score of 0. For patients with a risk score of 1, the relapse rates were 41%, 49% and 56% at 1, 2 and 5 years, respectively. All patients with a risk score of 2 relapsed (P = 0.01).

CONCLUSION

Our new scoring system may be useful for predicting relapses in patients with lamivudine-induced HBeAg loss. Treatment strategies should be individualized according to risk score.

To "be" or not to "be": that is the question

Treatment guidelines currently consider hepatitis B early antigen (HBeAg) seroconversion to be the end point of treatment with oral antivirals for HBeAg-positive patients. However, it is clear that with the high HBeAg relapse rate (both natural and after treatment) along with the high rate of mixed infection and the prevalence of HBeAg-negative disease, HBeAg status can no longer be considered the most useful end point of treatment or the signal to initiate therapy. Hepatitis B surface antigen (HBsAg) loss or seroconversion is associated with a favorable prognosis in both HBeAg-positive and HBeAg-negative disease and should be considered the test result that, combined with undetectable HBV DNA, will trigger treatment cessation.

Benefits and risks of nucleoside analog therapy for hepatitis B

Five oral agents have been approved for the treatment of chronic hepatitis B, ranging in virological potency, clinical efficacy, barrier to resistance, and side-effect profile. The degree of histological, biochemical, and serological improvement with therapy generally corresponds to the degree of suppression of serum hepatitis B virus (HBV) DNA achieved with therapy. Conversely, for agents with a low barrier to resistance, the profundity of HBV DNA suppression in individual patients correlates inversely with the likelihood of resistance. The durability of hepatitis B e antigen (HBeAg) responses after a consolidation period of an additional 6-12 months of therapy is approximately 80% in western populations, lower in Asian populations. Loss of hepatitis B surface antigen (HBsAg) during a year of oral-agent therapy is limited, except with the most potent agents, but extending therapy for a second year and beyond can yield frequencies of HBsAg responses close to those reported in trials of interferon-based therapy. The oral agents are approved for 1-2 years of therapy, but treatment is continued indefinitely in the majority of patients (except for the approximately 20% of patients who are HBeAg-reactive who achieve a durable HBeAg response). HBeAg responses and virological/biochemical benefit continue to be maintained and to increase with continued therapy beyond the first year. Data continue to accumulate supporting the link between long-term HBV DNA suppression and reduction in hepatic fibrosis, hepatic decompensation, and liver-related mortality. All the benefits of a single year of injectable peginterferon therapy can be achieved with the newer, low-resistance oral agents continued beyond the first year, without interferon side effects. Future studies are needed to develop drug regimens that are even more effective in achieving clinical endpoints, that are not hampered by resistance, and that are more confined in treatment duration but are more durable.

Development of a novel mouse model to evaluate drug candidates against hepatitis B virus

Woodchuck hepatitis virus (WHV)-infected woodchucks have been used for preclinical development of drugs against hepatitis B virus (HBV). However, there is no simple in vivo model to evaluate small amounts of compounds against HBV. To develop such a model, HepAD38 cells, in which HBV replication is regulated by tetracycline (tet), were grown as subcutaneous tumours in nude mice. Mice developing viraemia were then left untreated or given tet in the drinking water. In some of the mice given tet, it was removed and the mice were injected intraperitoneally with phosphate buffer saline (PBS), lamivudine (3TC), clevudine (CLV) or tenofovir dipivoxil fumarate (TDF). Virus DNA titres were measured by real-time PCR during and after drug treatment. In water-fed and PBS-injected mice, virus titres reached approximately 10(9) copies/ml serum within 35 days of HepAD38 injection, whereas in tet-treated mice, virus titres remained at 10(4)-10(5) copies/ml. HBV DNA levels were suppressed by 3TC, TDF and CLV, with the latter two drugs showing more sustained virus suppression compared with 3TC. Combination therapy with CLV plus TDF was much more effective than either drug alone in suppressing virus titre for at least 3 weeks after the end of treatment. There was no demonstrable toxicity to HepAD38 cells in drug-treated mice. Hence, a robust tet-controlled system for HBV replication in vivo was demonstrated, validated with monotherapies against HBV and shown to be useful in assessing combination therapy. This system will be useful for preclinical assessment of small amounts of single or multiple compounds against HBV in vivo.

Economic implications of entecavir treatment in suppressing viral replication in chronic hepatitis B (CHB) patients in China from a perspective of the Chinese Social Security program

OBJECTIVES

Of estimated 112 million persons infected with chronic hepatitis B (CHB) in China, 15% to 40% will eventually develop liver complications. Most patients do not actively seek antiviral agents for treatment due in part to lack of good understanding of the disease. Entecavir is a new therapeutic option for CHB patients and the purpose of this study was to evaluate the cost-effectiveness of entecavir treatment in China, based on projected clinical benefits from its superior viral suppression efficacy.

METHODS

The analysis was based on the perspective of the Chinese Social Security program. Adjusted relative risks on the association between viral load (VL) and clinical end points (liver cirrhosis/hepatocellular carcinoma) were derived from a publication of a Taiwan CHB prospective cohort with 42,115 person-years of follow-up, and applied to patients enrolled in a randomized phase III trial in China. In this trial, hepatitis B virus (HBV) DNA (by polymerase chain reaction assay) was the key efficacy end point after 48 weeks of treatment with either entecavir or lamivudine monotherapy. Entecavir and lamivudine daily prices were assumed to be Renminbi Yuan (RMB) 40 and 16.71, respectively. Life expectancy tables were based on China vital statistics. Direct medical cost and utility scores for different phases of CHB were estimated from published China specific data, and costs were adjusted to 2006 values using the Chinese Consumer Price Index. Probabilistic sensitivity analyses were conducted to evaluate parameter uncertainty on event distribution and treatment failure rates beyond the trial period.

RESULTS

A total of 519 subjects were enrolled in the study, comprising of 82% males, 87% HBeAg+, and a mean age of 30 years. Based on the efficacy measurement of the percentage of patients achieving HBV DNA <300 copies/ml at week 48, entecavir was superior to lamivudine (78.7% vs. 46.7%, respectively [P < 0.05]). In the base case, compared with lamivudine, 1 year of entecavir therapy gained 0.305 quality-adjusted life year (QALY) at an incremental cost of 5368 RMB, with a 3% annual discount. Compared with lamivudine, using entecavir cost an incremental 17,590 RMB per QALY gained (95% CI 6333-56,407).

CONCLUSIONS

Based on the results of this study, entecavir is likely to be cost-effective in treating hepatitis B patients in China based on the World Health Organization's recommended maximum willingness to pay threshold.

Efficacy of hepatitis B virus (HBV) vaccination in treating lamivudine-resistant HBV reactivation following hepatitis B surface antigen seroconversion

BACKGROUND

HBsAg vaccination might help to control HBV replication following nucleos(t)ide analog therapy. We tested HBsAg vaccine in a patient who developed lamivudine resistance.

PATIENT AND RESULTS

An HBeAg negative HBV chronically-infected patient developed HBsAg seroconversion after 3 years of treatment by lamivudine. However, the control of HBV replication was transient and HBV DNA could be detected in the serum one year after lamivudine was stopped. Concurrently, the anti-HBs antibodies (HBsAb) titre had decreased from more than 100 IU/L to 23 IU/L. Due to the presence of rtM204V resistance mutation, lamivudine was not reintroduced and the patient was treated by HBsAg vaccination. After three injections, HBV DNA was no more detectable and the HBsAb titre reached more than 200 IU/L.

CONCLUSION

This observation suggests that a regular follow up of patients presenting HBsAg seroconversion following lamivudine therapy is necessary. In these patients, a low titre of HBsAb may not prevent from lamivudine-resistant HBV reactivation. Evaluation of HBsAg vaccination to maintain HBsAb at a high titre in these patients deserves further studies.

Genotyping and genomic sequencing in clinical practice

The global prevalence of chronic hepatitis B and its associated serious sequelae demand technologically advanced techniques of management. Nucleic acid testing (NAT) plays a key role in the diagnosis, surveillance, and treatment of chronic hepatitis B. NAT includes quantitative PCR-based HBV DNA assays, HBV genotyping, tests for mutations associated with resistance to antiviral medications, and assays to detect precore and core promoter mutations. This article reviews the uses of NAT in the diagnosis and management of chronic hepatitis B.

Lamivudine/pegylated interferon alfa-2b sequential combination therapy compared with lamivudine monotherapy in HBeAg-negative chronic hepatitis B

BACKGROUND AND AIM

Monotherapy has been proven insufficient in achieving sustained control of chronic hepatitis B. We aimed to assess the efficacy of combined sequential administration of lamivudine and pegylated interferon alfa-2b in patients with hepatitis Be antigen (HBeAg)-negative chronic hepatitis B.

METHODS

Eighteen patients were given sequential combination treatment starting with 3 months of lamivudine monotherapy followed by 9 months of pegylated interferon alfa-2b (after a 3-month period of concomitant administration of the two drugs) and 24 patients received lamivudine monotherapy.

RESULTS

At the end of treatment, 88.9% of the patients who received sequential combination treatment and 70.8% of those who received lamivudine monotherapy had hepatitis B virus (HBV) DNA levels below 400 copies/mL (P = not significant). At the end of treatment, 72.2% of the patients who received sequential combination treatment and 70.8% of those who received lamivudine monotherapy achieved alanine aminotransferase normalization (P = not significant). After 12 months of follow up, 33.3% of the patients who received sequential combination treatment and 16.7% of those who received lamivudine monotherapy had HBV-DNA levels below 400 copies/mL (P = 0.4). After 12 months of follow up, 72.2% of the patients who received sequential combination treatment and 25.0% of those who received lamivudine monotherapy had normal alanine aminotransferase levels (P < 0.01). Twenty-five percent of the patients in the lamivudine monotherapy group had virological breakthrough compared to none in the sequential combination treatment group (P = 0.06).

CONCLUSIONS

Sequential combination treatment is able to improve sustained biochemical response rates and prevent the emergence of lamivudine-resistant mutants in patients with HBeAg-negative chronic hepatitis B.

Comparative cost-effectiveness of antiviral therapies in patients with chronic hepatitis B: a systematic review of economic evidence

BACKGROUND AND AIM

Economic efficiency of the alternative antiviral therapies for chronic hepatitis B has not been systematically investigated and their quality remains unknown. The aim of the present study was to systematically overview economic evidence of antiviral therapies for chronic hepatitis B.

METHODS

We searched six databases and eight major journals supplemented with screening references of eligible studies. Full economic evaluations comparing alternative antiviral therapies in patients with chronic hepatitis B virus infection were included. Two investigators assessed the study quality and transferability, independently. Data were analyzed qualitatively with adjustment when appropriate.

RESULTS

Fourteen studies (six modeling vs eight trials and database analyses) were included. Quality was high in five studies, moderate in one US and five Chinese studies, and low in three Chinese studies. The major problems of quality are costing methods and analysis and the presentation of results. In Australia and Poland, lamivudine-preferred strategies dominated interferon (IFN)-alpha and its related strategy from the health-care sector perspective. In the US, adefovir salvage produced US$8446 per additional quality-adjusted life years (QALY) compared with IFN-alpha. In Spain, the cost of adefovir was US$34,840 for additional virological response. In Taiwan, the use of pegylated IFN-alpha (pegIFN-alpha) produced US$11,711.4 per additional QALY, compared with lamivudine. In China, the incremental cost-effectiveness ratios of combination therapy lamivudine ranged from US$2860 to US$22,160 per additional loss of hepatitis B e antigen (HBeAg), and IFN-alpha versus lamivudine ranged from US$2490 to US$8890 per additional loss of HBeAg.

CONCLUSION

The cost-effectiveness frontiers of treatment alternatives vary and are influenced by the comparators and socioeconomic conditions of countries. Lamivudine-containing therapy is cost-effective when newer antiviral agents (e.g. adefovir/pegIFN-alpha) were not available. Economic methods should be further improved in studies, particularly in China.

Clinical outcomes of chronic hepatitis B patients with persistently detectable serum hepatitis B virus DNA during lamivudine therapy

BACKGROUND AND AIM

A small proportion of chronic hepatitis B patients have persistently detectable serum hepatitis B virus (HBV) DNA despite lamivudine therapy. The incidence and clinical outcomes of patients who persistently have detectable serum HBV-DNA during lamivudine therapy was investigated.

METHOD

We enrolled 221 chronic hepatitis B patients who underwent lamivudine therapy for more than 6 months. Among them, 180 were HBeAg positive. Serum HBV-DNA, HBeAg, anti-HBe and alanine aminotransferase (ALT) levels were serially monitored. The study groups were defined, using a hybridization assay, as patients with reductions in serum HBV-DNA below the detectable level (group I) or patients with persistently detectable serum HBV-DNA (group II) during the initial 6 months of lamivudine therapy.

RESULTS

The incidence of patients who had persistently detectable HBV-DNA was 7.7%. After the first year, the rates of viral breakthrough, HBeAg loss and serum ALT normalization of group I versus group II were 21% versus 63%, 38% versus 0%, and 71% versus 28%, respectively (P < 0.001). The log(10) reduction of serum HBV-DNA at 6 months was -4.58 log(10) for group I and -1.97 log(10) for group II (P < 0.001, bDNA assay). There were no pretreatment lamivudine-resistant mutants in group II.

CONCLUSION

Lamivudine had little effect on serum HBV-DNA suppression, viral breakthrough suppression and rate of HBeAg loss and ALT normalization in chronic hepatitis B patients with persistently detectable serum HBV-DNA during the initial 6 months of therapy. Early termination of lamivudine therapy is advocated for these patients.

Cross-study analysis of the relative efficacies of oral antiviral therapies for chronic hepatitis B infection in nucleoside-naive patients

BACKGROUND AND OBJECTIVE

Lamivudine and adefovir were approved for treatment of chronic hepatitis B virus (HBV) infection based on placebo-controlled trials, and entecavir was recently approved on the basis of its superiority over lamivudine in phase II/III trials; however, to date, these three therapies have not been compared head to head.

METHODS

To evaluate the relative efficacy of these therapies, we applied a predefined protocol of established statistical techniques to compare data from phase III entecavir trials with published clinical trial results with lamivudine, adefovir and placebo in nucleoside-naive hepatitis B e antigen (HBeAg)-positive and -negative populations.

RESULTS

A comprehensive literature search identified 612 publications/data sources, of which 28 satisfied predefined inclusion criteria. Independent reviewers extracted week 48-52 histological, virological, biochemical and serological endpoints from these sources, which were analysed with a fixed-effects model. For each of the three histological endpoints in HBeAg-positive patients (Histological Improvement, Ranked Assessment of Necroinflammation [RA-N] and Ranked Assessment of Fibrosis [RA-F]), entecavir was superior to adefovir. Entecavir was superior to lamivudine for Histological Improvement and comparable to lamivudine for RA-N and RA-F. With respect to reducing HBV DNA levels, entecavir (-6.98 log(10) copies/mL) was more effective than lamivudine (-5.46 log(10) copies/mL, p < 0.0001) and adefovir (-3.60 log(10) copies/mL, p < 0.0001), and lamivudine was more effective than adefovir (p < 0.0001). The parallel goals of HBV DNA reduction below the limit of quantitation (LOQ) [by polymerase chain reaction] and ALT normalisation were achieved more often with entecavir (69% and 67% of patients, respectively) than with lamivudine (38% and 59%, respectively; p < 0.0001 and p < 0.05, respectively) or adefovir (21% and 48%, respectively; both p < 0.0001), and more often with lamivudine than with adefovir (p < 0.0001 and p < 0.05, respectively). HBeAg seroconversion rates were higher with entecavir (21% of patients) and lamivudine (18%) than with adefovir (12%, p < 0.01 and p < 0.05, respectively). For each of the three histological endpoints in the HBeAg-negative population, entecavir was comparable to adefovir. Entecavir was superior to lamivudine for Histological Improvement, and comparable to lamivudine for RA-N and RA-F, and all three antivirals were superior to placebo. Entecavir proved superior to lamivudine and adefovir in lowering HBV DNA levels (-5.20 vs -4.66 vs -3.91 log(10) copies/mL, respectively; p < 0.0005 and p < 0.0001, respectively) and in suppressing HBV DNA below the LOQ (91% vs 73% vs 51% of patients, respectively; both p < 0.0001); in the latter respect, lamivudine was in turn superior to adefovir (p < 0.0001). Entecavir was also superior to lamivudine in normalising ALT (76% vs 69% patients, respectively; p < 0.05).

CONCLUSIONS

Over a 12-month treatment period, this analysis predicts that the antiviral efficacy of entecavir would be superior to that of lamivudine, which in turn would be superior to that of adefovir, in nucleoside-naive patients with chronic HBV infection.

Serum HBV RNA is a predictor of early emergence of the YMDD mutant in patients treated with lamivudine

Lamivudine (LAM) is a nucleoside analogue widely used for the treatment of chronic hepatitis B virus (HBV) infection. Emergence of resistant strains with amino acid substitutions in the tyrosine-methionine-aspartate-aspartate (YMDD) motif of reverse transcriptase is a serious problem in patients on LAM therapy. The amount of covalently closed circular DNA in the serum is reported to be higher in patients who develop YMDD mutants than in those without mutants. However, there is no useful serum marker that can predict early emergence of mutants during LAM therapy. Analysis of patients who were treated with entecavir (n=7) and LAM (n=36) showed some patients had high serum levels of HBV RNA. Median serum levels of HBV RNA were significantly higher in patients in whom the YMDD mutant had emerged within 1 year (n=6, 1.688 log copies/ml) than in those in whom the YMDD mutant emerged more than 1 year after treatment (n=12, 0.456 log copies/ml, P=0.0125) or in whom the YMDD mutant never emerged (n=18, 0.688 log copies/ml, P=0.039). Our results suggest that HBV RNA is a valuable predictor of early occurrence of viral mutation during LAM therapy.

Clinical outcome of renal transplantation in patients with positive pre-transplant hepatitis B surface antigen

The clinical outcomes of 2,054 renal recipients were examined retrospectively based on pre-transplant hepatitis B surface antigen (HBsAg) status to investigate the efficacy of lamivudine treatment in HBsAg positive recipients. Pre-transplant HBsAg positivity was documented in 66 recipients. The 10-year patient and graft survival rates in Ag positive group were significantly lower than those of Ag negative group (64.4/36.6% vs. 88.2/70.5%, respectively, P < 0.0001). Since 1997, lamivudine was used when hepatitis B virus polymerase chain reaction (HBV PCR) was positive or when the level of post-transplant viral load rose. Lamivudine given to 27 recipients markedly improved both 10-year patient and graft survivals compared to Ag positive renal recipients who did not take lamivudine (85.3/59.2% vs. 49.9/22.7%, respectively, P < 0.0001). Overall, 13 viral breakthroughs among 24 lamivudine-responsive patients were observed. The cumulative incidence of viral breakthrough at 60 months was 53.3%. Adefovir rescue in three viral breakthroughs patients induces virological response and restoration of liver function. In 10 patients who did not changed to adefovir, 6 patients are alive with elevated liver enzymes. In conclusion, in the era of lamivudine and adefovir, renal transplantation in HBsAg positive end-stage renal disease patients should not be abandoned.

[The role of lamivudine in the treatment of HBe antigen negative liver cirrhosis]

INTRODUCTION

Lamivudine is effective in suppressing hepatitis B virus replication and hepatic necroinflammatory activity. Patients with HBV-related chronic liver disease often present with hepatic decompensation and are not eligible for interferon therapy. The effectiveness of antiviral therapy in preventing disease progression in patients with hepatitis B cirrhosis is unknown. The aim of this study was to evaluate the effectiveness of lamivudine treatment in patients with cirrhosis due to chronic hepatitis B.

MATERIAL AND METHODS

The study included 24 patients with cirrhosis B. During one year, all of them were treated with Lamivudine (100 mg/day). All patients underwent routine laboratory tests and abdominal ultrasound. After that, they were followed-up from 1-15 months.

RESULTS AND DISCUSSION

Most patients presented with improved general condition. We also noticed a reduction in SBP, ALT level, bilirubin level, hepatic encephalopathy and ascites. Five patients died, due to HCC, and two due to variceal bleeding. There was no significant improvement in liver synthetic function.

CONCLUSION

Lamivudine is highly effective in reducing viral load in HBeAg-negative patients significantly improving the clinical and biochemical status of liver functions.

Clinical significance of hepatitis B e antigen level easurement during long-term lamivudine therapy in chronic hepatitis B patients with e antigen positive

AIM: To determine the changes of quantitative hepatitis B e antigen (HBeAg) that predicts early detection of non-response or breakthrough to long-term lamivudine (LAM) therapy.

METHODS: Among HBeAg positive chronic hepatitis B patients who failed to achieve HBeAg seroconversion within 12 mo, we retrospectively analyzed 220 patients who had received LAM more than 24 mo.

RESULTS: The mean duration of LAM therapy was 36 (range, 24-72) mo. HBeAg seroconversion after the first 12 mo of LAM therapy was achieved in 53 (24.1%) patients. Viral breakthrough was observed in 105 (47.7%) patients. To find out whether the changing patterns of HBeAg levels can predict the outcome of LAM therapy, we analyzed the reduction rates of HBeAg levels during LAM therapy. Using the decrease more than 90% of pretreatment HBeAg levels, the sensitivity and specificity of response were 96.2% and 70.1%, respectively. Patients were divided into 3 groups according to the reduction patterns of the decrease of quantitative HBeAg: decrescendo, decrescendo-crescendo, no change or fluctuating groups. The optimal time to predict non-response or breakthrough was the first 9 mo of therapy. At 9 mo of therapy, 49 (92.5%) of 53 patients who had achieved HBeAg seroconversion were included in the decrescendo group. On the contrary, in the no change or fluctuating group, only four (7.5%) had achieved HBeAg seroconversion. Among patients who did not show the continuous decrease of HBeAg levels at 9 mo, 95.2% (negative predictive value) failed to achieve HBeAg seroconversion.

CONCLUSION: Almost all patients who failed to show a continuous decrease of HBeAg levels at 9 mo of LAM therapy were non-response or breakthrough. Therefore, monitoring changes of HBeAg levels during LAM therapy in HBeAg positive chronic hepatitis B may be valuable for identifying patients who are at high risk of non-response or breakthrough.

Sustained clinical improvement of a patient with decompensated hepatitis B virus-related cirrhosis after treatment with lamivudine monotherapy

Hepatitis B virus (HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, remains a major health problem in Asian countries. Recent development of vaccine for prevention is reported to be successful in reducing the size of chronically infected carriers, although the standard medical therapies have not been established up to now. In this report, we encountered a patient with decompensated HBV-related cirrhosis who exhibited the dramatic improvements after antiviral therapy. The patient was a 50-year-old woman. Previous conventional medical treatments were not effective for this patient, thus this patient had been referred to our hospital. However, the administration of lamivudine, a reverse transcriptase inhibitor, for 23 months dramatically improved her liver severity. During this period, no drug resistant mutant HBV emerged, and the serum HBV-DNA level was continuously suppressed. These virological responses were also maintained even after the antiviral therapy was discontinued. Moreover, both hepatitis B surface antigen and e antigen were observed to have disappeared in this patient. The administration of lamivudine to patients with HBV-related cirrhosis, like our present case, should be considered as an initial medical therapeutic option, especially in countries where liver transplantation is not reliably available.

A novel accurate ACRS-PCR method with a digestion internal control for identification of wild type and YMDD mutants of hepatitis B virus strains

As a consequence of the point mutation in the YMDD motif of the hepatitis B virus (HBV) polymerase gene, lamivudine-resistant mutants have been reported in chronic hepatitis B patients who underwent lamivudine therapy. The objective of the study was to develop a novel accurate artificially created restriction site (ACRS) method with a digestion internal control for identification of YMDD, YIDD and YVDD HBV strains. Three conserved, specific and diagnostic primers introducing NdeI, SspI and AleI cleavage sites were designed in order to identify YMDD, YIDD and YVDD strains, respectively; while, their reverse primers also modified with the above recognition sites in order to enzyme correctness monitoring and false outcome avoiding. Thirty-two chronic hepatitis B patients who had taken lamivudine for 1-3 years and checked by the Inno-LiPA HBV DR kit, were evaluated by the ACRS method and then compared to sequencing data. The results of the ACRS method revealed the YMDD mutant strain in 20 patients, YMDD plus YIDD pattern in 1 patient, YMDD plus YVDD in 4 patients, the YIDD in 4 patients and mixed infection with each three strains in 1 patient. The sequencing and Inno-LiPA results were in agreement with the ACRS results. The novel ACRS method is a reliable, rapid and a cost-effective technique for determination of HBV strains with the wild type and YMDD mutant patterns.

Chronic hepatitis B: current testing strategies

The worldwide burden of hepatitis B mandates accurate and timely diagnosis of patients infected with the hepatitis B virus (HBV) and the use of treatment strategies derived from evidence-based guidelines. HBV is a DNA virus that produces a series of viral protein products circulating HBV DNA. Serologic and nucleic acid testing are critical to disease prevention and treatment objectives. Information from such testing helps determine patients' infectivity and immune status, appropriate monitoring strategies, and the efficacy of treatment, as well as providing data that contributes to a better understanding of the natural history and epidemiology of the disease. This article reviews the clinical use of state-of-the-art serologic and nucleic acid tests, including the relevance of hepatitis B e antigen and antibody and HBV DNA measurements as markers of disease activity. Viral load can be used to distinguish between active and inactive disease, define response to therapy, and detect the development of antiviral resistance. Some recent reports have suggested that high viral load is associated with poorer patient outcomes (eg, more rapid progression to cirrhosis and a higher incidence of hepatocellular carcinoma). Durable suppression of HBV DNA is evolving to become the primary goal of therapy, although all currently licensed medications have used histology as the primary end point of therapy. Suggested frequencies for HBV DNA monitoring are presented.

Pharmacology of current and promising nucleosides for the treatment of human immunodeficiency viruses

Nucleoside antiretroviral agents are chiral small molecules that have distinct advantages compared to other classes including long intracellular half-lives, low protein binding, sustained antiviral response when a dose is missed, and ease of chemical manufacture. They mimic natural nucleosides and target a unique but complex viral polymerase that is essential for viral replication. They remain the cornerstone of highly active antiretroviral therapy (HAART) and are usually combined with non-nucleoside reverse [corrected] transcriptase and protease inhibitors to provide powerful antiviral responses to prevent or delay the emergence of drug-resistant human immunodeficiency virus (HIV). The pharmacological and virological properties of a selected group of nucleoside analogs are described. Some of the newer nucleoside analogs have a high genetic barrier to resistance development. The lessons learned are that each nucleoside analog should be treated as a unique molecule since any structural modification, including a change in the enantiomeric form, can affect metabolism, pharmacokinetics, efficacy, toxicity and resistance profile.

Comparison of Two Different Regimens of Combined Interferon-α2A and Lamivudine Therapy in Children with Chronic Hepatitis B Infection

Aim

To evaluate the efficacy of two regimens of combined interferon-α2a (IFN-α2a) and lamivudine (3TC) therapy in childhood chronic hepatitis B.

Methods

A total of 177 patients received IFN-α2a, 9 million units (MU)/m2 for 6 months. In group I (112 patients, 8.7±3.5 years), 3TC (4 mg/kg/day, max 100 mg) was started simultaneously with IFN-α2a, in group II (65 patients, 9.6±3.8 years) 3TC was started 2 months prior to IFN-α2a. 3TC was continued for 6 months after antiHBe seroconversion or stopped at 24 months in non-responders.

Results

Baseline alanine aminotransferase (ALT) was 134.2 ±34.1 and 147.0 ±45.3; histological activity index (HAI) was 7.4 ±2.7 and 7.1 ±2.3; and HBV DNA levels were above 2,000 pg/ml in 76% and 66% of patients in groups I and II, respectively ( P>0.005). Complete response was 55.3% and 27.6% in groups I and II, respectively ( P<0.01). AntiHBe seroconversion was higher and earlier, and HBV DNA clearance was earlier in group I ( P<0.05). HBsAg clearance was 12.5% and 4.6% and antiHBs seroconversion was 9.8% and 6.2% in groups I and II, respectively ( P>0.05). Breakthrough occurred in 17.9% and 24.6%; breakthrough times were 15.9 ±4.6 and 14.1 ±5.1 months; and relapse rates were 6.8% and none in groups I and II, respectively ( P>0.05, P>0.05, P>0.05). Responders had higher HAI (HAI>6) and higher pre-treatment ALT than non-responders.

Conclusion

Simultaneous 3TC+IFN-α2a yields a higher response and earlier antiHBe seroconversion and viral clearance than consecutive combined therapy. Relapse rate is low. Predictors of response are high basal ALT and high HAI scores. 3TC can be administered for 24 months without any side effect and breakthrough rate is comparable with previous studies.

Early virological response predicts outcome during extended lamivudine retreatment in patients with chronic hepatitis B who relapsed after initial HBeAg responses

BACKGROUND AND AIM

Studies from hepatitis B virus endemic areas have shown less durable lamivudine-induced responses and have raised issues about the management of a post-treatment relapse.

METHODS

From January 2000 to June 2004, all 51 patients (43 HBeAg-positive and eight HBeAg-negative) were retreated with lamivudine for at least 12 months. All had a post-treatment relapse after HBeAg responses (HBeAg loss/seroconversion) during the first therapy.

RESULTS

During retreatment, HBeAg seroconversion occurred more frequently in those patients with HBeAg seroconversion than in those with HBeAg loss alone during prior lamivudine therapy (P = 0.001). On multivariate analysis, prior HBeAg seroconversion and early virological response (EVR) (< or = 2 months of retreatment) independently predicted HBeAg seroconversion (P = 0.012 and P = 0.004, respectively). With regard to virological breakthrough, only the time to virological response (> 2 months of retreatment) remained significant (P = 0.048). Among the HBeAg-negative patients, virological breakthrough occurred in only one patient with a late virological response.

CONCLUSIONS

EVR is a major predictor in determining a favorable response to lamivudine retreatment. Our observations suggest that lamivudine retreatment will provide more therapeutic gains in those patients with a prior HBeAg seroconversion than in those with HBeAg loss alone.

Factors related to post-treatment relapse in chronic hepatitis B patients who lost HBeAg after lamivudine therapy

BACKGROUND AND AIM

It is uncertain if a patient's lamivudine response after HBeAg loss is durable. In Korean chronic hepatitis B patients, the relapse rate is high after termination of lamivudine therapy for patients with HBeAg loss. We evaluated the factors related to relapse in chronic hepatitis B patients with HBeAg loss after lamivudine therapy.

METHODS

A total of 132 chronic hepatitis B patients, who initially had HBeAg and did not have decompensated features, were analyzed in this study. These patients lost the HBeAg after lamivudine therapy and then their therapy was stopped. Post-treatment serum alanine aminotransferase (ALT), HBeAg, anti-HBe and hepatitis B virus (HBV) DNA were monitored until relapse.

RESULTS

Seventy-five patients relapsed (cumulative relapse rate: 56% at 6 months). Upon univariate analysis, the factors of age, serum total bilirubin, presence of anti-HBe after HBeAg loss, and the duration of additional lamivudine therapy after HBeAg loss were associated with relapse. Upon multivariate analysis, older age, a higher serum total bilirubin and the shorter duration of additional lamivudine therapy were significant risk factors for relapse. Patterns of relapse were the re-elevation of ALT, re-emergence of HBV DNA (69 patients) and reappearance of HBeAg (55 patients).

CONCLUSIONS

To prevent relapse in patients with chronic hepatitis B infection after lamivudine therapy, age and serum bilirubin level of patients as well as a prolonged duration of additional lamivudine therapy should be considered.

Current treatment and future directions in the management of chronic hepatitis B viral infection

The World Health Organization places hepatitis B virus (HBV) in the top 10 causes of death worldwide. It is estimated that there are over 400 million carriers of HBV as well. At least 20% to 30% of hepatitis B surface antigen (HBsAg) carriers will die of complications of chronic liver disease, including cirrhosis and liver cancer. The serious consequences of end-stage liver disease and liver cancer occur in 30% of chronic carriers and confront patients and physicians throughout the world. Vaccination is the major form of treatment (prevention) that may eventually eliminate HBV worldwide. This article discusses the currently available treatments as well as evolving treatments for chronic HBV infection.

Long-term results of lamivudine monotherapy in Korean patients with HBeAg-positive chronic hepatitis B: response and relapse rates, and factors related to durability of HBeAg seroconversion

OBJECTIVE

The aim of this study was to evaluate retrospectively the long-term effects of lamivudine in 461 Korean patients with chronic hepatitis B who were treated for more than 12 months.

METHODS

The annual rates of virological response and breakthrough were examined and the predictive factors for post-treatment relapse in 114 patients who achieved hepatitis B e antigen (HBeAg) loss or seroconversion after lamivudine therapy were also analyzed.

RESULTS

During follow-up, the rates of HBeAg seroconversion after 1, 2, 3, 4 and 5 years of treatment were 22.9, 33.2, 47.6, 54.2 and 58.8%, respectively, while those for virological breakthrough at 1, 2, 3 and 4 years were 8.2, 41.7, 55.7 and 64.8%, respectively. Ninety-five patients (20.6%) had HBeAg seroconversion and 19 (4.1%) showed HBeAg loss alone with disappearance of hepatitis B virus DNA in serum. Seroconversion was higher with prolonged treatment in patients who had elevated serum alanine aminotransferase. The cumulative relapse rates in the seroconversion group were 52.0 and 55.7% 1 and 2 years after treatment, respectively. Age and the duration of additional treatment were significant predictive factors for post-treatment relapse. Patients aged </=40 who had additional treatment for >12 months after seroconversion had the lowest relapse rate (p < 0.001).

CONCLUSIONS

These results suggest that additional treatment for over 12 months after HBeAg seroconversion in younger patients may produce a better long-term outcome.

Virological and biochemical relapse after discontinuation of lamivudine monotherapy for chronic hepatitis B in Japan: comparison with breakthrough hepatitis during long-term treatment

OBJECTIVE

Comparison of virological and biochemical relapse in patients with chronic hepatitis B, based on continuation or discontinuation of lamivudine monotherapy.

METHODS

In Japanese genotype C-dominant hepatitis B patients, 25 patients who stopped treatment at normal levels of alanine transferase (ALT) were retrospectively compared with 75 patients who continued treatment. Both groups were matched for age, sex, and observation period after start of treatment. We investigated the relapse rates, and evaluated predictive factors for relapse and efficacy of retreatment of the discontinuous group.

RESULTS

Virological and biochemical relapse occurred significantly earlier in the discontinuous than continuous group, and the peak levels and ratios of peak to pretreatment levels of serum bilirubin and ALT after relapse were not significantly different between the two groups. Multivariate analysis identified three independent factors at discontinuation of treatment associated with early biochemical relapse: HBeAg positivity, presence of liver cirrhosis, detection of basic core promoter mutant. Normalization of ALT levels with retreatment occurred in 62.5% of patients, but 2 HBeAg-positive patients retreated after the emergence of YMDD motif mutant developed severe relapse with hyperbilirubinemia.

CONCLUSION

Our results in Japanese patients with genotype C-dominant hepatitis B suggest that discontinuation of lamivudine monotherapy, and retreatment after the emergence of YMDD mutant should be given attention.

Viral kinetics in patients with lamivudine-resistant hepatitis B during adefovir-lamivudine combination therapy

BACKGROUND/AIMS

Mathematical analysis of viral kinetics during lamivudine-adefovir combination therapy has not yet been performed in patients with lamivudine-resistant hepatitis B.

METHODS

In 8 patients with lamivudine-resistant hepatitis B, adefovir dipivoxil (10 mg/day) was added to ongoing lamivudine. Viral decay during the first 8 weeks of combination therapy was described by a biphasic model to determine the efficacy: epsilon, of blocking viral production, the clearance: c, of free virus, and the loss of infected cells: delta.

RESULTS

Median epsilon was 98%, median c was 0.7/day, and median delta was 0.07/day. No significant association was found between viral kinetic and baseline parameters and virologic and biochemical treatment response. When compared with viral kinetic constants reported for higher dose adefovir dipivoxil monotherapy, epsilon was lower (P=0.026) and delta was higher (P=0.008) in this study whereas c did not differ between both studies.

CONCLUSIONS

Although a recent study did not show any differences in the reduction of HBV DNA comparing monotherapy with adefovir dipivoxil to adefovir-lamivudine combination therapy in patients with lamivudine-resistant chronic hepatitis B, mathematical analysis of early viral kinetics suggests an additional effect of lamivudine on the infected cell loss during adefovir-lamivudine combination therapy.

Safety and antiviral activity of emtricitabine (FTC) for the treatment of chronic hepatitis B infection: a two-year study

BACKGROUND/AIMS

The aim of this study was to evaluate long term safety and antiviral activity of different doses of emtricitabine given once daily to patients chronically infected with hepatitis B.

METHODS

Eligible patients were randomized in a double-blind, parallel study to evaluate 25, 100 or 200 mg once daily doses of emtricitabine for 48 weeks. Patients were then followed for an additional 48 weeks on open-label 200 mg emtricitabine. Serum HBV DNA, ALT, and hepatitis B serology were measured at regular intervals over the 2 years. Resistance surveillance was performed after 1 and 2 years on viremic samples, i.e. > 4700 copies/mL.

RESULTS

Emtricitabine was well tolerated and produced a dose proportional antiviral response. After 2 years, 53% of the patients had serum HBV DNA < or = 4700 copies/mL, 33% seroconverted to anti-HBe and 85% had normal ALT. Eighteen percent of the patients who had received 200 mg emtricitabine for 2 years developed resistance mutations.

CONCLUSIONS

Emtricitabine was well tolerated and demonstrated a potent antiviral response for up to 2 years in patients with chronic hepatitis B infection. Based on these data, 200 mg emtricitabine once daily was chosen as the optimal dose for future hepatitis B studies.

Response to long-term lamivudine treatment (up to 5 years) in patients with severe chronic hepatitis B, role of genotype and drug resistance

Lamivudine is effective in suppressing viral replication, normalizing alanine aminotransferase (ALT), and improving histological appearance in HBe positive and negative hepatitis. It is unclear whether hepatitis B virus (HBV) genotype influences the response to lamivudine. We report the long-term response of patients with chronic hepatitis B with and without cirrhosis at baseline treated with lamivudine according to HBV genotype. Retrospective review of charts of all patients treated with lamivudine monotherapy between 1993 and 2002. Response to therapy defined as ALT in the normal range, undetectable HBV DNA, and in the HBeAg positive group loss of HBeAg and/or the development of anti-HBe. HBV DNA measured by the Digene Hybrid capture assay (sensitivity 1.4 x 10(6) copies/mL). YMDD mutation at rtL180M and rtM204V/I measured by restriction digest of amplified products. Genotyping performed by sequencing and phylogenetic tree analysis of the preS region of the virus genome. Seventy-one patients treated with lamivudine for 6 months or more, 53 (75%) were male, average age 47 years, 38 (54%) were HBeAg+ and 33 (46%) HBeAg-. Mean baseline HBV DNA viral titre was 1280.2 copies/mL and 518 copies/mL respectively. Cirrhosis was present in 30 (42%). Sera were examined for YMDD mutations at last patient visit in 61 (86%), and were detected in 45 (74%), there being no association with a particular genotype. Data from up to 5 years on lamivudine indicated no difference in biochemical or virological response between genotypes. Cirrhosis was more prevalent with specific genotypes. We found no influence of HBV genotype on the development of resistance to lamivudine, however liver disease severity was influenced by genotype.