Long-term experience with lamivudine therapy for hepatitis B virus infection after liver transplantation

A Very Short Course of HBIg+NA Followed by Entecavir or Tenofovir Monotherapy Prevents HBV Recurrence in Low-Risk Liver Transplant Recipients

BACKGROUND

Monoprophylaxis with third-generation nucleos(t)ide analogues (NAs) can be safely adopted in hepatitis B virus (HBV)-positive, liver transplantation (LT) patients after at least 6 months of HBV immunoglobulin (HBIg)+NA. We investigated the efficacy of earlier initiation of post-LT entecavir (ETV) or tenofovir (TDF) monoprophylaxis.

METHODS

Between September 2011 and January 2017, all consecutive hepatitis B surface antigen (HBsAg)-positive transplanted patients were scheduled to receive HBIg with ETV or TDF for a period related to the risk for HBV reinfection: 1. low-risk patients (HBeAg-negative and HBV DNA < 12 IU/mL before LT) were due to withdraw from HBIg once HBsAg had become negative after a minimum of 7 days of HBIg+NA; 2. high-risk patients were due to receive HBIg for at least 6 months, after which they continued with third-generation NA monotherapy, only.

RESULTS

Twenty patients with a median interquartile range (IQR) follow-up of 46 (64-39) months were enrolled in the study (40% receiving ETV, 60% receiving TDF). Two low-risk patients refused early HBIg withdrawal and were therefore treated and analyzed along with the high-risk group. Eventually, there were 2 groups: group A, which included 12 low-risk patients, and group B, which included 8 patients (six high-risk, 2 low-risk). After transplantation, group A and B patients received HBIg+NA for a median (IQR) time of 7 (9-7) days and 9 (13-5) months, respectively. All 20 recipients demonstrated HBV DNA < 12 IU/mL and stable graft function during follow-up. Two patients (10%), 1 from each group, had HBsAg relapse. Notably, both patients who relapsed had hepatocellular carcinoma (HCC) diagnosed before LT and showed very low levels (< 0.25 IU/mL) of HBsAg after recurrence.

CONCLUSION

In low-risk HBsAg-positive recipients, HBIg may be safely discontinued within 2 weeks of LT and replaced by ETV or TDF monotherapy.

Safe and cost-effective control of post-transplantation recurrence of hepatitis B

A combination of hepatitis B immunoglobulin (HBIG) and nucleoside/nucleotide analogs (NUC) is the current standard of care for controlling hepatitis B recurrence after orthotopic liver transplantation (OLT). However, long-term HBIG administration is associated with several unresolved issues, including limited availability and extremely high cost, and thus several protocols for treatment with low-dose HBIG combined with NUC or HBIG-free regimens have been developed. This article reviews recent advances in post-OLT hepatitis B virus (HBV) control and future methodological directions. New NUC such as entecavir, tenofovir or lamivudine plus adefovir dipivoxil combinations induce a very low frequency of viral resistance. The withdrawal of HBIG after several months of OLT under new NUC continuation also has permissible effects. Even after HBV reactivation, NUC can usually achieve viral control when viral markers are strictly followed up. Another approach is to induce self-producing anti-HBV antibodies via vaccination with a hepatitis B surface antigen vaccine. However, HBV vaccination is not sufficiently effective in patients to treat liver cirrhosis type B after OLT because immune tolerance to the virus has already continued for several decades. Trials of its safety and cost-effectiveness are required. This review advocates a safe and economical approach to controlling post-OLT HBV recurrence.

KASL Clinical Practice Guidelines: Management of chronic hepatitis B

The guideline on the management of chronic hepatitis B (CHB) was first developed in 2004 and revised in 2007 by the Korean Association for the Study of the Liver (KASL). Since then there have been many developments, including the introduction of new antiviral agents and the publications of many novel research results from both Korea and other countries. In particular, a large amount of knowledge on antiviral resistance--which is a serious issue in Korea--has accumulated, which has led to new strategies being suggested. This prompted the new guideline discussed herein to be developed based on recent evidence and expert opinion.

TARGET POPULATION

The main targets of this guideline comprise patients who are newly diagnosed with CHB and those who are followed or treated for known CHB. This guideline is also intended to provide guidance for the management of patients under the following special circumstances: malignancy, transplantation, dialysis, coinfection with other viruses, pregnancy, and children.

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.

Current therapeutic strategies for recurrent hepatitis B virus infection after liver transplantation

Hepatitis B virus (HBV)-related liver disease is the leading indication for liver transplantation (LT) in Asia, especially in China. With the introduction of hepatitis B immunoglobulin (HBIG) and oral antiviral drugs, the recurrent HBV infection rate after LT has been evidently reduced. However, complete eradication of recurrent HBV infection after LT is almost impossible. Recurrent graft infection may lead to rapid disease progression and is a frequent cause of death within the first year after LT. At present, the availability of new oral medications, especially nucleoside or nucleotide analogues such as adefovir dipivoxil, entecavir and tenofovir disoproxil fumarate, further strengthens our ability to treat recurrent HBV infection after LT. Moreover, since combined treatment with HBIG and antiviral agents after liver re-transplantation may play an important role in improving the prognosis of recurrent HBV infection, irreversible graft dysfunction secondary to recurrent HBV infection in spite of oral medications should no longer be considered an absolute contraindication for liver re-transplantation. Published reviews focusing on the therapeutic strategies for recurrent HBV infection after LT are very limited. In this article, the current therapeutic strategies for recurrent HBV infection after LT and evolving new trends are reviewed to guide clinical doctors to choose an optimal treatment plan in different clinical settings.

Current management of hepatitis B virus infection before and after liver transplantation

The progress in treatment against hepatitis B virus (HBV) has substantially improved the outcome of all HBV-infected patients. We systematically reviewed the existing data in the management of HBV transplant patients in order to assess the optimal regimen in the pretransplant setting, for post-transplant prophylaxis and for therapy of HBV recurrent infection. All data suggest that an effective pretransplant anti-HBV therapy prevents post-transplant HBV recurrence. Pretransplant therapy has been based on lamivudine with addition of adefovir upon lamivudine resistance, but the use of newer, potent high-genetic barrier agents is expected to improve long-term efficacy. Moreover, it may lead to improvement of liver function, which sometimes removes the need for transplantation, although more objective criteria for removal from waiting lists are required. After liver transplantation, the combination of HBV immunoglobulin and one nucleos(t)ide analogue, mostly lamivudine, is currently the best approach, almost eliminating the probability of HBV recurrence. Treatment of post-transplant HBV recurrence has been mainly studied with lamivudine, but it will be most effective with entecavir and tenofovir, which have a low risk of resistance. In conclusion, the newer anti-HBV agents improve the treatment of HBV both pretransplant and post-transplant. HBV immunoglobulin is still used in combination with an anti-HBV agent for post-transplant prophylaxis. Monoprophylaxis with one of the new anti-HBV agents might be possible, particularly in patients preselected as having a low risk of HBV recurrence, but further data are needed and strategies to ensure compliance must be used.

Favorable outcome of de novo hepatitis B infection after liver transplantation with lamivudine and adefovir therapy

De novo hepatitis B virus (HBV) infection after orthotopic liver transplantation (OLT) always progresses to chronic hepatitis because of the patients' immunocompromised status, and only a few then acquire hepatitis B surface antigen (HBsAg) seroconversion even with efficient antiviral therapy. Here we reported the case of a liver transplant recipient with de novo HBV infection who had a favorable outcome after lamivudine (LAM) and adefovir dipivoxil (ADV) antiviral therapy. The patient received OLT because of end-stage primary biliary cirrhosis and was found to have de novo HBV infection 3 months later. She was treated with LAM, and her serum HBV DNA turned undetectable 2 weeks later. However, serum HBV DNA turned detectable again after 9 months of LAM therapy and a YMDD mutation was detected. The addition of ADV was efficient to treat LAM-resistant HBV. After 3 months of combination therapy, LAM was stopped and ADV monotherapy was continued. HBsAg seroconversion was achieved after an additional 12 months. The prevention and treatment of de novo HBV infection after OLT is discussed.

Prophylaxsis against recurrance of hepatitis B virus after liver transplantation: a retrospective analysis spanning 20 years

Liver transplantation (LT) in patients with hepatitis B virus (HBV) infection is associated with a high rate of graft loss and poor survival, unless re-infection can be prevented. Human hepatitis B immune globulin (HBIG) has long been utilized to prevent re-infection. More recently, an anti-viral agent has been utilized along with HBIG. However, the regimens utilized have varied considerably among LT programmes and the optimal regimen has never been defined. We conducted a retrospective analysis of 41 patients who underwent LT for HBV at our centre since 1985 and received either HBIG with or without an anti-viral agent. The mean age of these patients was 46 years; 81% were male and 88% white. The mean and maximal follow-up were 5.9 and 15 years respectively. Eight out of 15 E-antigen-positive patients who received HBIG alone developed recurrence after a mean of 17 months. In contrast, none of 10 E-Ag-negative patients who received HBIG alone and none of the 10 E-antigen-positive patients who received both HBIG and either lamivudine or adefovir developed recurrence. As long as the anti-HB surface remained detectable, no absolute minimum serum level appeared to lead to recurrent HBV. We concluded that recurrence of HBV following LT can be prevented in E-antigen-positive patients with a combination of HBIG and an anti-viral agent. In contrast, recurrence can be prevented in E-antigen-negative patients with HBIG alone. Maintaining a serum anti-HB surface level above a minimum arbitrary titre of 200 pg/mL did not appear to be necessary for effective HBIG prophylaxis.

Hepatitis B in liver transplant recipients

1. The use of low-dose immunosuppressive therapy along with pre- and posttransplantation nucleos(t)ide therapy and posttransplantation hepatitis B immunoglobulin (HBIG) has yielded marked improvements in survival. 2. Lamivudine (Epivir-HBV), adefovir (Hepsera), entecavir (Baraclude), tenofovir (Viread), emtricitabine (Emtriva), and the combination drugs tenofovir + emtricitabine (Truvada) and abacavir + lamivudine (Epzicom) are effective nucleos(t)ide antiviral agents that, in some cases, may help reverse liver disease sufficiently to avoid transplant. 3. In posttransplantation patients, virus suppression with some combination of HBIG and the nucleos(t)ide agents may prevent graft loss and death or the need for a second transplant. 4. In both the pre- and posttransplantation setting, the goal of hepatitis B virus management is complete virus suppression. 5. The use of low-dose intramuscular HBIG is evolving, with studies showing that dosing and cost can be reduced by 50-300% with a customized approach. 6. Elimination of HBIG from the treatment paradigm is currently under evaluation and may be possible with the use of newer medications that have no or low resistance rates. 7. Although there is growing evidence that some types of combination therapy may decrease the chance that drug resistance will develop and increase the likelihood of long-term success in preventing graft loss and death, additional research will be required to determine which combinations will work well in the long term, and which will not.

Established and emerging therapies for the treatment of viral hepatitis

Patients who are chronically infected with either hepatitis B or C viruses run the risk of developing cirrhosis and hepatocellular carcinoma in later life. Antiviral treatment offers the only means of interrupting this progression. To date, recombinant interferon alpha and the nucleos(t)ide analogues lamivudine and adefovir dipivoxil are the only licensed drugs for the treatment of chronic hepatitis B, whilst recombinant or pegylated interferons in combination with ribavirin are the ones used for chronic hepatitis C virus infections. The efficacy of these treatments, reasons for treatment failure, drug resistance and future options are discussed in the present review.

Study on the Efficacy and Safety of Adefovir Dipivoxil Treatment in Post–Liver Transplant Patients With Hepatitis B Virus Infection and Lamivudine-Resistant Hepatitis B Virus

Hepatitis B virus (HBV) recurrence and de novo HBV infection are frequent events in liver transplantation recipients. Treatment with lamivudine is initially efficient in both infections but the incidence of lamivudine-resistant HBV emergence increases over time. Adefovir appears to be promising in post-liver transplantation patients with recurrent HBV infection and lamivudine-resistant HBV. This study analyzed adefovir treatment in 42 post-liver transplantation patients who developed recurrent HBV or de novo HBV infection with lamivudine-resistant HBV (54.8% HCV-coinfected). Patients received 10 mg of oral adefovir once daily for a mean period of time of 21.5 months (range from 12 to 31 months). In 62.9% of patients, ALT levels decreased significantly. Serum HBV-DNA was undetectable in 64% of the cases. Twenty percent of patients lost HBeAg marker and 13.3% of them developed anti-HBe. In 9.5% of recipients, HBsAg became negative. There was no significant change in serum creatinine levels. In only one patient was worsening of the renal function detected, making dose adjustment necessary. No other side effects were reported. Our results confirm the efficacy and safety of adefovir treatment in post-liver transplantation patients with lamivudine-resistant HBV, neither were adefovir-resistant mutations identified in patients after 21 months of therapy, nor were there adverse events, especially renal toxicity.

YMDD variants of HBV DNA polymerase gene: Rapid detection and clinicopathological analysis with long-term lamivudine therapy after liver transplantation

AIM: To look for a rapid low-cost technique for the detection of HBV variants.

METHODS: Two patients who underwent orthotopic liver transplantation (OLT) for HBV infection were treated with lamivudine (100 mg daily) and HBV infection recurred in the grafted livers. The patients were monitored intensively for liver enzymes, hepatitis B surface antigen (HBsAg) and HBV DNA in serum. Liver biopsy was performed regularly. HBV DNA in a conserved polymerase domain (the YMDD locus) was amplified from serum of each patient by PCR and sequenced. HBV genotypes were analyzed by restriction fragment length polymorphism (RFLP) of the PCR products generated from a fragment of the polymerase gene.

RESULTS: YMDD wild-type HBV was detected in one patient by PCR-RFLP and DNA sequencing 19 mo after OLT, and YIDD mutant-type HBV in the other patient, 16 mo after OLT.

CONCLUSION: PCR-RFLP assay is an accurate and simple method for genotyping lamivudine-resistant HBV variants.

Treatment of hepatitis B and C after liver transplantation. Part 1, hepatitis B

The outcome of OLT for HBV-related liver disease is dependent on the prevention of allograft re-infection. Over the past decade, major advances have been made in the management of HBV transplant candidates. The advent of long-term hepatitis B immune globulin (HBIG) administration as a prophylaxis against HBV recurrence, and the introduction of new antiviral agents against HBV infection, such as lamivudine (LAM), were a major breakthrough in the management of these patients. Results of OLT for HBV infection are similar to those achieved with other indications. Pre-OLT antiviral treatment such as LAM can suppress HBV replication before OLT and thus decrease the risk of re-infection of the graft. Combination prophylaxis with LAM and HBIG after transplantation highly effectively reduces the rate of HBV re-infection, even in HBV replicative cirrhotic patients. The optimal HBIG protocol in the LAM era is yet to be defined: dosing of HBIG, routes of administration, and possibility of stopping HBIG. Several antiviral drugs have been developed for the management of HBV infection on the graft, so outcome is currently good.

Liver transplantation for HBV and management of reinfection

Follicular non-Hodgkin's lymphoma (NHL) represents the most common indolent lymphoma with a median survival of 10 years. A new prognostic index (FLIPI) provides prognostic information at diagnosis and at relapse. Initial treatments combining monoclonal antibody therapy using rituximab with chemotherapy appear to increase the response rate and decrease the risk of relapse with little increase in toxicity. Promising phase III trial results demonstrating improvements in outcome using rituximab have recently been reported. A number of phase II trials have also demonstrated encouraging activity combining radiolabeled antibodies in sequence with chemotherapy. The role of high-dose therapy and autologous transplantation is becoming more defined, with improvements in progression-free survival observed in the upfront and relapsed setting. The application of allogeneic transplantation, once restricted to young otherwise healthy patients has shown encouraging activity in older, relapsed, and refractory patients using nonmyeloablative conditioning regimens. These new treatment options make the management of newly diagnosed patients both exciting and a challenge.

Lamivudine treatment for acute severe hepatitis B: a pilot study

BACKGROUND

Experience with lamivudine treatment of immunocompetent patients with acute hepatitis B is limited.

AIM OF STUDY

To evaluate the safety and efficacy of lamivudine for the treatment of acute severe hepatitis B virus (HBV) infection in immunocompetent adults.

PATIENTS AND METHODS

Fifteen patients (10 men, 5 women, mean age 34.3+/-7.3 years) with severe acute HBV infection were treated with lamivudine 100 mg daily for 3-6 months, starting 3-12 weeks after onset of infection. Prior to treatment, 5 patients had grade 1-4 encephalopathy; all patients had severe coagulopathy (mean INR was 4.5+/-6.4), and all patients had evidence of severe hepatocyte lysis (mean alanine aminotransferase 3738+/-1659 U/L, and mean total serum bilirubin 18+/-6.8 mg/dl). All patients had evidence of highly replicative HBV (mean HBV DNA 13.5 x 10(6)+/-11 x 10(6) copies/ml).

RESULTS

Thirteen patients (86.6%) responded to treatment. Encephalopathy disappeared within 3 days of treatment and coagulopathy improved within 1 week. Serum HBV DNA was undetectable (by polymerase chain reaction) within 4 weeks, and serum liver enzyme levels normalized within 8 weeks. Two patients in whom lamivudine therapy was delayed developed fulminant hepatitis and underwent urgent liver transplantation. (One died of vascular complications 1 month later). The 11 patients who were serum HBeAg-positive before treatment seroconverted, and HBeAb developed within 12 weeks in 9 of them; HBsAg was undetectable in all 11 tested patients, and protective titer of HBsAb developed within 12-16 weeks in 9 of them. Therapy was well tolerated in all cases.

CONCLUSIONS

These data indicate that lamivudine induces a prompt clinical, biochemical, serological and virological response in immunocompetent patients with de novo HBV infection. Lamivudine may prevent the progression of severe acute disease to fulminant or chronic hepatitis and should be considered for use in selected patients. A large randomized controlled, double-blind prospective study is needed.

Current therapies for chronic hepatitis B virus infection

Patients who are chronically infected with the hepatitis B virus are at an increased risk of developing cirrhosis, hepatic decompensation and hepatocellular carcinoma. Therapeutic intervention offers the only means of interrupting this progression. Currently there are three licensed agents for the treatment of chronic hepatitis B virus infection. These are interferon-alpha, an immunomodulator, and two synthetic nucleos(t)ide analogs, namely lamivudine (Epivir, GlaxoSmithKline) and adefovir dipivoxil (Hepsera, Gilead Sciences). This review aims to summarize current experience with these drugs in the treatment and management of patients with chronic hepatitis B virus infection, their efficacy, and current problems of drug resistance. An outline of future treatment perspectives is also included.

Liver transplant and recurrent disease

Current prophylactic measures have greatly reduced recurrence rates of hepatitis B after liver transplantation. HBIG remains a critically important compound and although there is variability in dosing regimens and target anti-HBs levels, it is the backbone of recurrence prevention. Adjuvant therapies with nucleoside/nucleotide analogs alone have been limited by drug-resistant strains of HBV, but the armamentarium of these molecules continues to grow and hence the management of the post-LT HBV patient will evolve further. Currently lamivudine with HBIG remains an excellent option provided the patient has not developed resistance, especially in the pre-LT period. Adefovir is the drug of choice in that setting and perhaps the preferred drug in the pre-LT setting to allow the use of lamivudine post-LT. Further testing with tenofovir and newer compounds in development will expand these options. The use of multiple nucleoside analogs is an intriguing option, based on the HIV experience of reducing drug resistance and optimizing viral suppression, and will likely be further studied.

Adefovir dipivoxil therapy for lamivudine-resistant hepatitis B in pre- and post-liver transplantation patients

Three-hundred and twenty-four patients were enrolled in an open-label, multicenter, international study in which pre- and post-liver transplantation (LT) patients with recurrent chronic hepatitis B (CHB) and evidence of lamivudine-resistant HBV were treated with adefovir dipivoxil 10 mg once daily. In the pre- and post-LT cohorts, 128 and 196 patients were treated for a median duration of 18.7 and 56.1 weeks, respectively. In patients who received 48 weeks of treatment, 81% of the pre-LT and 34% of the post-LT cohort achieved undetectable serum hepatitis B virus (HBV) DNA (Roche Amplicor Monitor polymerase chain reaction [PCR] assay lower limit of quantification [LLQ] < 400 copies/mL) with a median change in serum HBV DNA from baseline of -4.1 log(10) and -4.3 log(10) copies/mL, respectively. Serum alanine aminotransferase (ALT), albumin, bilirubin, and prothrombin time normalized in 76%, 81%, 50%, and 83% of pre-LT patients and 49%, 76%, 75%, and 20% of post-LT patients. The Child-Pugh-Turcotte (CPT) score improved in over 90% of patients in both cohorts. Genotypic analysis of 122 HBV baseline samples revealed that 98% of these patients had lamivudine-resistant mutant HBV. No adefovir resistance mutations were identified in patients after 48 weeks of therapy. One-year survival was 84% for pre-LT and 93% for post-LT patients (Kaplan-Meier analysis). Treatment-related adverse effects associated with adefovir dipivoxil in this setting were primarily mild to moderate in severity. In conclusion, 48 weeks of adefovir dipivoxil resulted in significant improvements in virologic, biochemical, and clinical parameters in CHB patients pre- and post-LT with lamivudine-resistant HBV.

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Experience with lamivudine therapy for hepatitis B virus infection before and after liver transplantation, and review of the literature

OBJECTIVES

To analyse the results of lamivudine therapy on suppression of hepatitis B virus (HBV) replication before transplantation and on preventing graft reinfection postoperatively.

DESIGN

Long-term clinical study.

SETTING

Liver Institute and Department of Transplantation of a tertiary-care university-affiliated centre.

SUBJECTS

(1) 14 candidates for liver transplantation with decompensated liver disease caused by active replication of HBV; (2) six patients with recurrent HBV infection after transplantation.

INTERVENTION

Lamivudine 100 mg daily; administered in group 1 before surgery and continued after in nine patients who underwent transplantation; administered in group two postoperatively only. anti-hepatitis B surface antigen immunoglobulin (HBIg) was administered postoperatively in both groups.

MAIN OUTCOME MEASURES

Immunoassay evaluation of serum hepatitis B surface antigen, serum hepatitis Be antigen and serum HBV DNA (hybridization and PCR); sequencing through the tyrosine-methionine-aspartate-aspartate locus of the HBV polymerase gene in patients with lamivudine breakthrough; inflammation and fibrosis scoring on liver biopsy before and at least 2 years after lamivudine therapy in group 2.

RESULTS

Pretransplantation therapy (group 1) significantly suppressed HBV replication and enabled nine patients (64.2%) to undergo transplantation. Only one patient (7.1%) had lamivudine breakthrough, and one (7.1%) had recurrent HBV. Lamivudine administration begun after transplantation (mean 48.0 months, range 30-60 months) because of graft reinfection (group 2) was associated, over the long-term, with the emergence of high mutation rates (83.3%), histological disease progression (66.6%), and hepatic failure (33.3%).

CONCLUSIONS

In patients with chronic HBV infection and active viral replication, lamivudine therapy is effective when started before transplantation. However, its long-term administration after transplantation for recurrent HBV leads to high resistance rates. Combination therapy with lamivudine and HBIg immunoglobulin can substantially reduce the recurrence rate. Further studies on combination antiviral therapy are needed in this patient population.

Prevention of and treatment for hepatitis B virus infection after liver transplantation in the nucleoside analogues era

Post-transplant prophylaxis with hepatitis B immune globulin (HBIG) has significantly reduced hepatitis B virus (HBV) recurrence rates, but it is rather ineffective in patients with pretransplant viremia. Moreover, long-term HBIG administration is very expensive and may be associated with emergence of escape HBV mutants. Lamivudine has been widely used in the management of HBV transplant patients. Pretransplant lamivudine lowers HBV viremia, decreasing the risk of post-transplant HBV recurrence, but to try and minimize development of resistant HBV strains, it should start within the last 6 months of the anticipated transplantation timing. Preemptive post-transplant lamivudine monotherapy is associated with progressively increasing HBV recurrence rates, but combined therapy with lamivudine and HBIG at relatively low dosage is currently the most effective approach in this setting, even in HBV-DNA-positive patients, who also receive lamivudine in the pretransplant period. The most frequent therapy for post-transplant HBV recurrence is lamivudine, but the increasing resistance rates represent a rather challenging problem. Adefovir dipivoxil and entecavir are currently the most promising agents for lamivudine-resistant HBV strains. All these advances in anti-HBV therapy have made HBV liver disease an indication for liver transplantation irrespective of viral replication status, a complete turn around from 10 years ago.

Hepatitis B core antibody-positive grafts: recipient's risk

The transmission of hepatitis B virus infection through hepatitis B core antibody (anti-HBc)-positive liver grafts in hepatitis B surface antigen (HBsAg)-negative recipients has been established. The mandatory use of immunosuppression in transplant patients favors reactivation of latent virus that may be present in grafts from HBsAg-negative anti-HBc-positive donors. With the persistent organ donor scarcity, the use of these grafts cannot be avoided, especially in urgent cases and in areas where the prevalence of the hepatitis B virus is high, as in Asia. The recognition of posttransplant de novo hepatitis B from core antibody-positive liver donors has, therefore, led to modifications in graft allocation policies and the introduction of strategies for prophylaxis. The risk of developing this type of new-onset hepatitis B virus infection in liver transplant recipients and the various approaches to minimize this risk are reviewed. The peculiar implications of using core antibody-positive grafts in the context of living donor liver transplantation in Asia are discussed.

Effect of lamivudine against HBV reinfection after liver transplantation

AIM: To assess the prophylactic effect of lamivudine in preventing reinfection of HBV and the dynamic alternations of HBV markers in serum and liver tissue after liver transplantation.

METHODS: Twenty five recipients were non-randomly divided into HBV active replicating group (15 cases) and HBV non-active replicating group (10 cases) and control group (3 cases). Lamivudine 100 mg /day was administered to each patient before and after operation, 3 of 10 cases in non-active replicating group failed to take lamivudine on time and thus was grouped as control. The HBV markers in serum and bioptic liver tissues in 25 recipients were evaluated regularly with enzyme-linked radioimmunoassay, HBV DNA fluorescent quantitative assay, immunohistochemistry stain LSAB and digoxin labeled HBV DNA hybridization in situ.

RESULTS: Serum HBV DNA in 80% cases with active HBV replication became negative following 2-week periods of lamivudine treatment prior to liver transplantation. HBsAg in all recipients converted to negative after liver transplantation. HBsAb (9/15), HbcAb(13/15) and HBeAb (11/15) appeared within one week postoperatively, and disappeared gradually within 6 months. Serum HBV DNA was negative; Results of in situ hybridization in bioptic liver tissue showed that HBsAg, HBcAg as well as HBV DNA remained negative after treatment of lamivudine. 10 of 15 recipients had got to clinical clearance of HBV, HBV markers were undetectable in both serum and liver biopsy samples between 12 to 44 weeks (average 24 weeks), 1-, 2-year survival rate in this group reached 83%. Two of 15 subjects (13.3%) developed allograft HBV reinfection or recurrence of hepatitis in 2 years after the prophylactic treatment of lamivudine. In HBV non-active replicating group, the outcome was similar with that in the active group. The HBV antibody was HBsAb (+, 4/7), HBcAb (+, 6/7), HBeAb (+, 2/7), 3 of 7 recipients achieved HBV clinical clearance in both serum and liver bioptic samples, while in control group, all 3 recipients developed allograft HBV reinfection and recurrent hepatitis in 8, 10 and 12 months post-transplantation, respectively, one of three died from fibrosing cholestatic hepatitis, the other 2 cases recovered after the additional therapy of lamivudine. The overall allograft reinfection rate was 9.1% (2/22) and the overall 1-, 2-year accumulative survival rate was 87% in patients received lamivudine.

CONCLUSION: Lamivudine can effectively prevent liver allograft from HBV reinfection in HBV related decompensated liver cirrhosis and even in HBV active replicating recipient.

Genotypic and phenotypic resistance: longitudinal and sequential analysis of hepatitis B virus polymerase mutations in patients with lamivudine resistance after liver transplantation

OBJECTIVE

Lamivudine-resistant strains appear in 27-62.5% of liver transplant recipients treated with lamivudine for hepatitis B virus (HBV) recurrence, and may lead to failure of antiviral therapy. In an extension of our previous study, we investigated the molecular events associated with the emergence of lamivudine-resistant mutants in this population.

METHODS

Sequential serum samples from 10 consecutive patients with lamivudine resistance after liver transplantation were analyzed for viral genotype, precore mutants, and viral polymerase gene mutants (L528M, M552V, M552I) using restriction fragment length polymorphism. Quantitative analysis of HBV DNA was performed using hybridization assay and polymerase chain reaction.

RESULTS

Eight patients (80%) were infected with genotype D and two (20%) with genotype C. Polymerase mutants (genotypic resistance) were identified in all the patients. Phenotypic resistance (rise in serum HBV DNA titers above the detection limit of the hybridization assay) developed in five patients (50%); of the remainder, three (30%) did not have phenotypic resistance, and two were primary nonresponders. Genotypic resistance was detected earlier than phenotypic resistance (median 285 days [range 42-510] vs median 387 days [range 320-420], p = 0.055). In five patients (50%), the emergence of the YMDD mutants took over the wild type; in three (30%), the YMDD mutant took over the wild type, but the wild type re-emerged during lamivudine therapy; and in two (20%), the YMDD mutants were detected in a mixture with the wild type (in different percentages). The mean pretreatment serum ALT level was significantly lower in the patients who did not develop phenotypic resistance (p = 0.0002). The M552I pure viral population was found mainly in these patients, and all retained stable graft function (median follow-up 33 months). A high pretreatment HBV DNA level (>50 x 10(6) copies/ml) was highly statistically significantly correlated with the rapid occurrence of phenotypic resistance (r = -0.90, p = 0.04).

CONCLUSIONS

We reached the following conclusions: 1) In our area, liver transplant recipients who develop resistance to lamivudine given for recurrent HBV infection seem to be mainly infected with genotype D. 2) Re-emergence of the wild type can occur during lamivudine therapy. 3) Genotypic resistance precedes phenotypic resistance, although phenotypic resistance does not always follow genotypic resistance. 4) Quantitative determination of viremia and analysis of polymerase gene mutants are recommended for monitoring antiviral therapy of liver transplant patients with HBV reinfection in the graft.

Treatment of recurrent hepatitis B infection in liver transplant recipients

1. Therapeutic decisions are guided by a patient's clinical status (severity of disease and presence of comorbidities) and previous drug-exposure history. 2. Lamivudine is safe and effective in liver transplant recipients with recurrent hepatitis B virus (HBV) infection caused by wild-type virus or failure of hepatitis B immunoglobulin therapy. Lamivudine resistance, developing in approximately 25% after 12 months of therapy, is its main limitation. 3. Famciclovir is safe in liver transplant recipients; however, virological and clinical responses are less consistent than with lamivudine. Thus, lamivudine is favored over famciclovir as first-line therapy in transplant recipients with no previous exposure to nucleoside analogues. 4. Although limited in availability, adefovir dipivoxil appears safe and effective in treating liver transplant recipients with lamivudine-resistant HBV disease. Close monitoring of renal function is recommended, with dose adjustment in patients with reduced creatinine clearances. 5. Limited data suggest that intravenous ganciclovir, tenofovir disoproxil fumarate, and interferon alfa may be useful as rescue therapies for patients with lamivudine- or famciclovir-resistant HBV disease. 6. Antiviral therapy with two or more suitable agents may minimize the chance for viral resistance; therefore, future therapeutic strategies likely will use combination therapy in the long-term management of recurrent HBV disease.

Hepatitis B: progress in the last 15 years

1. Patients undergoing orthotopic liver transplantation (OLT) for hepatitis B without effective prophylaxis have a high risk for recurrent infection and severe graft damage, leading to death or re-OLT. 2. Long-term prophylaxis with hepatitis B immune globulin (HBIg) significantly reduces the risk for hepatitis B virus (HBV) recurrence and increases survival. Patients with detectable HBV DNA at the time of OLT have a high risk for recurrence despite HBIg prophylaxis. 3. Lamivudine (LAM) therapy for patients with decompensated HBV cirrhosis before OLT results in inhibition of viral replication and clinical improvement. Its efficacy is limited by the frequent emergence of LAM-resistant YMDD mutations. The ideal length of therapy with LAM pre-OLT has not yet been defined. 4. Prophylaxis of HBV recurrence with LAM monotherapy is not recommended because of the reappearance of hepatitis B surface antigen after OLT in approximately 50% of patients. 5. LAM is the best available treatment for patients with established recurrent hepatitis B. Long-term therapy is associated with the emergence of drug-resistant mutants in up to 60% of patients. Severe hepatitis and liver failure have been described among liver transplant recipients with YMDD mutations. 6. Combination therapy with HBIg and LAM prevents HBV recurrence in 90% to 100% of patients who undergo OLT for hepatitis B. The optimal HBIg protocol in the LAM era is yet to be defined. 7. Preliminary studies suggest that adefovir dipivoxil inhibits HBV replication in patients infected with LAM-resistant HBV strains. 8. Fifteen years ago, hepatitis B was regarded as a relative or absolute contraindication for OLT. Today, hepatitis B is a universally accepted indication for OLT.

Clinical impact and efficacy of lamivudine therapy in de novo hepatitis B infection after liver transplantation

De novo hepatitis B virus (HBV) infection after orthotopic liver transplantation (OLT) in patients negative for hepatitis B surface antigen (HBsAg) is between 1.7% and 3.5% in areas with a low prevalence of HBV infection. The importance of this problem and the efficacy of lamivudine treatment has not been defined in areas with a high prevalence of positivity to antibody to hepatitis B core antigen (Anti-HBc). To define the characteristics and the clinical impact of de novo HBV infection in OLT recipients and to evaluate the efficacy of lamivudine treatment in this context, 229 HBsAg (-) donors (145 men, 84 women) were retrospectively evaluated between June 1994 and June 2000. Forty-eight recipients were excluded for various reasons. The final study population included 181 patients that were prospectively followed up for more than 6 months after OLT. When de novo HBV infection was detected, liver allograft biopsy was performed and treatment with lamivudine was indicated if patients were HBV-DNA-positive with elevated ALT levels. Survival time was defined as the interval between diagnosis of HBV infection and death or last follow-up visit. Thirty-one of 229 liver donors (13.5%) were anti-HBc(+). After a mean follow-up of 54.4+/-30 months, 9 of the 181 recipients (5%) developed de novo HBV infection; 8 of 27 recipients (29.6%) of livers from anti-HBc(+) donors as compared with only one of 154 recipients (0.6%) of livers from anti-HBc(-) donors P < 0.005). Liver biopsies performed in 8 of 9 cases showed chronic active hepatitis in 7 patients and acute hepatitis in one patient who cleared HBV spontaneously during the first 3 months. Seven patients were treated with lamivudine for a mean period of 24.5 months; HBV-DNA became negative in 5 of 7 (71.4%), and HBeAg became undetectable in 3 of 6 patients (50%). Patient actuarial survival rates at 1, 3, and 5 years were 100%, 94.7%, and 81.2% for recipients of anti-HBc (+) livers and 95.2%, 83%, and 77.3% for recipients of anti-HBc (-) livers P = ns). In our area, the appearance of de novo HBV infection after OLT is related to grafting livers from anti-HBc (+) donors is associated with a benign outcome, with no liver failure or graft loss, and treatment with lamivudine is highly effective in the control of HBV replication.

Limited lamivudine and long-term hepatitis B immunoglobulin immunoprophylaxis for prevention of hepatitis B recurrence after liver transplantation

BACKGROUND

No consensus exists concerning dosage and duration of prophylactic hepatitis B immunoglobulin and lamivudine for prevention of hepatitis B recurrence after liver transplantation (LT).

METHODS

Lamivudine was discontinued 12 months after LT, maintaining hepatitis B immunoglobulin prophylaxis in eight patients who received lamivudine treatment before LT.

RESULTS

At LT, six patients were serum hepatitis B virus (HBV)-DNA negative, whereas two patients had low serum HBV-DNA levels. Hepatitis B surface (HBs) antigen and hepatitis B core antigen stained positively by immunohistochemistry in all hepatectomy specimens. All patients remained recurrence free during the 12 months on combination therapy with normal liver histological examination and negative HBs and HB core staining on biopsy specimens. No relapse occurred after lamivudine withdrawal during a median follow-up of 17.5 months (normal transaminases, negative serum HBs antigen, and HBV-DNA).

CONCLUSIONS

Discontinuation of lamivudine 12 months after LT is feasible and safe even in patients with ongoing low viral replication at LT, providing adequate prophylaxis with hepatitis B immunoglobulins.

Resistance surveillance in chronic hepatitis B patients treated with adefovir dipivoxil for up to 60 weeks

Current therapies for chronic hepatitis B virus (HBV) infection do not provide adequate long-term control of viral replication in the majority of patients. Monotherapy with nucleoside analogs, such as lamivudine and famciclovir, is effective for short periods but results in the emergence of drug-resistant HBV in a substantial number of patients within 1 year of therapy. Adefovir dipivoxil (ADV) has demonstrated clinical activity against wild-type and lamivudine-resistant HBV, but it is unclear whether resistance mutations will emerge after long-term therapy with this drug. To determine whether extended treatment with ADV led to the emergence of drug-resistant populations of HBV, we analyzed virus isolated from patients currently enrolled in a long-term open-label study. The reverse transcriptase domain of HBV polymerase was amplified and sequenced from patients that had received a cumulative exposure of up to 60 weeks of ADV. During our analyses, several previously unreported amino acid substitutions were observed in the reverse transcriptase domain of HBV. Importantly, none of the observed mutations occurred in more than 1 patient, nor were they associated with an adefovir-resistant phenotype in vitro. Furthermore, none of the patients from whom these mutant viruses were isolated had evidence of virologic rebound. In conclusion, these results, although based on a limited number of patients, suggest that treatment with ADV does not lead to the emergence of resistant virus after up to 60 weeks of therapy.

Seroconversion after the addition of famciclovir therapy in a child with hepatitis B virus infection after liver transplantation who developed lamivudine resistance

There is very little information about hepatitis B virus (HBV) infection in children after liver transplantation. This is the first report of the addition of famciclovir in a child who developed lamivudine resistance.A 5-year-old boy who was serum HBsAg-negative and was not vaccinated against HBV underwent living-related liver transplantation for fulminant hepatitis A. The donor was his mother, who was serum HBcAb-positive. No immunoprophylaxis was administered. HBV infection developed after 18 months and was treated with 3 mg/kg daily of lamivudine. Serum alanine aminotransferase normalized and HBV DNA load decreased significantly. Sixteen months later, lamivudine resistance developed; a mutation (M552I) was confirmed by sequencing through the YMDD locus of the HBV polymerase gene. The addition of 750 mg daily of famciclovir led to seroconversion and the disappearance of serum HBV DNA. Lamivudine in combination with famciclovir might be a therapeutic option for HBV reinfection after liver transplantation, also in children. Suppression of viral replication to undetectable values is possible even in the lamivudine-resistant mutant.

Hepatitis B and C in the liver transplant recipient: current understanding and treatment

1. Liver disease related to chronic viral hepatitis is the leading indication for orthotopic liver transplantation (OLT) worldwide. 2. The natural history of hepatitis B virus infection has been dramatically modified, and outcome has improved substantially in the last decade with the use of hepatitis B immunoglobulin and lamivudine. 3. Hepatitis C virus (HCV) recurrence, defined by histological injury, is almost universal, and a subset of patients (20% to 30%) develops allograft cirrhosis by the fifth year post-OLT. 4. Unfortunately, antiviral therapy for hepatitis C post-OLT, even when initiated preemptively before the development of histological recurrence in the first few weeks post-OLT, has failed to alter the natural history of HCV disease recurrence. 5. HCV-related allograft cirrhosis is associated with a high rate of decompensation and mortality.