Review of the pharmacological management of hepatitis B viral infection before and after liver transplantation

Antiviral prophylaxis against hepatitis B recurrence after liver transplantation: Current concepts

The advance in treatment against hepatitis B virus (HBV) infection with the development of nucleos(t)ide analogues (NAs) with high genetic barrier to resistance, including entecavir and tenofovir, has improved clinical outcomes of patients transplanted for HBV infection, by preventing HBV recurrence after liver transplantation (LT) effectively. Currently, after LT, the combination of hepatitis B immunoglobulin (HBIG) and a high-barrier NA is considered as the standard of care for prophylaxis against HBV recurrence. However, because of the high cost of intravenous high-dose HBIG, other routes of HBIG administration, such as intramuscular or subcutaneous, have come to the foreground. In addition, several transplant centres tend to use a NA as monoprophylaxis, following a short post-LT period of HBIG and NA combination. Lately, studies using HBIG-free prophylactic regimens with entecavir or tenofovir have shown promising outcomes in preventing HBV recurrence, mostly regarding patients with undetectable HBV DNA at the time of LT. Although vaccination against HBV has been an attractive prophylactic approach, its efficacy has been controversial. Moreover, further studies are needed regarding long-term outcomes of complete withdrawal anti-HBV prophylaxis. For patients transplanted for HBV/HDV co-infection, combined regimen should be administered for a longer period post-LT. Finally, the use of grafts from hepatitis B core antibody-positive donors is safe for HBV-negative recipients, with the administration of lifelong antiviral prophylaxis.

Epidemiological characteristics of de novo hepatitis B infection in liver transplant recipients-An experience from a tertiary care centre in Qatar

BACKGROUND

The emergence of hepatitis B surface antigen in a patient with previously negative hepatitis B virus (HBV) serology post-orthotropic liver transplant (OTLX) is known as de novo hepatitis B (DNHB). As there are no data on patients with DNHB available from Qatar, we aim to do a pioneer study indexing their clinical profile and epidemiology of patients with DNHB in Qatar.

MATERIALS AND METHODS

This descriptive epidemiological study was done by retrospectively reviewing records of 159 post-OTLX patients. HBV serology of these patients post-OTLX was reviewed, and 17 were identified as DNHB cases. Baseline epidemiological characteristics were defined and compared between DNHB cases and the rest. DNHB cases were analyzed statistically using the chi-square test and Kaplan-Meier curve.

RESULTS

The majority of the subjects were men (65%) and Qataris (40%). Mean age was 57.4 ± 12.5 years. Bulk of them underwent OTLX in China (44%). The overall incidence of DNHB was 10.7%, with transplants in China having significantly higher incidence than transplants from all other countries. The mortality rate was 23.5% in DNHB cases compared to 2.8% in non-DNHB. 67% of patients survived at least 64 months after the diagnosis of DNHB. Five-year survival did not vary significantly between those with DNHB and those without.

CONCLUSION

Orthotropic liver transplant in centers selecting donors liberally without screening for HBV poses the risk of DNHB. We recommend having protective levels of HBs antibodies before OTLX. Prophylactic antiviral treatment should be considered until peri-operative HBV transmission has been excluded by screening hepatic tissue for HBV DNA.

Significance of Hepatitis B Recurrence in Liver Transplantation Recipients

Background

A combination of antihepatitis B immunoglobulin and antiviral agents is the most common regimen for prophylaxis of hepatitis B recurrence after liver transplantation. However, hepatitis B recurrence still happens. The significance of hepatitis B recurrence is less mentioned.

Materials

Forty-eight of the 313 hepatitis B liver transplant recipients having hepatitis B recurrence were included in this study. The patients were divided into group A, the patients transplanted for hepatitis B-related liver failure, and group B, the patients transplanted for hepatitis B-related cirrhosis and HCC. The clinical manifestations after hepatitis B recurrence were recorded.

Results

Among the 48 patients with hepatitis B recurrence, 23 patients were in group A and 25 patients in group B. The age was 51.6 ± 9.4 years in group A and 52.8 ± 6.4 in group B (p = 0.869). The MELD score prior to transplantation was 23.1 ± 9.9 in group A patients and 12.9 ± 5.6 in group B patients (p < 0.001). The median (interquartile) interval from transplantation to hepatitis B recurrence was 10 (2-19) months for group A patients and 13 (8.5-35) months for group B patients (p = 0.051). After hepatitis B recurrence, the liver function was almost normal in both groups. In group B patients, 10 patients had HCC recurrence with 7 of 10 patients having hepatitis B recurrence earlier than HCC recurrence. The interval between hepatitis B and HCC recurrence was 1 to 15 months. The 1-, 3-, and 5-year survival rates were 82.6%, 73.9%, and 69.0%, respectively, for group A patients and 96%, 76%, and 68%, respectively, for group B patients (p = 0.713).

Conclusion

The patients have uneventful liver function under antiviral agent while hepatitis B recurred. For the patients having HCC prior to transplantation, close monitoring of HCC recurrence is necessary if hepatitis B recurs.

Long-term safety and efficacy of tenofovir disoproxil fumarate substitution for hepatitis B immunoglobulin following liver transplantation

Background and Aims

Limitations to the use of long‐term Hepatitis B Immunoglobulin (HBIg) following liver transplantation for hepatitis B (HBV) have led to the substitution of HBIg with oral nucleo(s)tide analogue prophylaxis. We prospectively assessed the long‐term safety and efficacy of switching to tenofovir disoproxil fumarate (TDF) from HBIg.

Methods

An open‐label, multicenter switch study was conducted to evaluate the substitution of TDF for HBIg whilst continuing lamivudine (LAM) therapy in preventing the recurrence of HBV in patients who had been maintained as hepatitis B surface antigen (HBsAg)‐negative posttransplantation for at least 12 months.

Results

Eighteen patients were enrolled (median age 66 years, range 42–78 years); 84% were male, and 78% on calcineurin inhibitors. Median time after transplantation was 14 years (range 5–19), and median duration of HBIg/LAM prior to the switch was 10 years (range 1–14). Median follow‐up was 5 years (range 5–8). Of 18 patients, 16 (89%) remained HBsAg and HBV DNA negative at the end of follow‐up. Two patients had re‐emergence of HBsAg without a detectable HBV DNA and no clinical sequelae. Creatinine clearance significantly reduced (median 59 mL/min to 51 mL/min, P = 0.03), necessitating dose reduction of TDF in six (33%) participants, with two eventually ceasing TDF. One patient switched back to HBIg by choice. All patients who changed therapy maintained an undetectable HBsAg.

Conclusion

Substitution of HBIg with TDF in patients on LAM is well tolerated and effective for the long‐term prevention of HBV recurrence posttransplantation. Renal dysfunction occurs frequently in the posttransplant setting and can require dose adjustment of TDF or change of therapy.

Reactivation of hepatitis B after liver transplantation: Current knowledge, molecular mechanisms and implications in management

Chronic hepatitis B (CHB) is a major global health problem affecting an estimated 350 million people with more than 786000 individuals dying annually due to complications, such as cirrhosis, liver failure and hepatocellular carcinoma (HCC). Liver transplantation (LT) is considered gold standard for treatment of hepatitis B virus (HBV)-related liver failure and HCC. However, post-transplant viral reactivation can be detrimental to allograft function, leading to poor survival. Prophylaxis with high-dose hepatitis B immunoglobulin (HBIG) and anti-viral drugs have achieved remarkable progress in LT by suppressing viral replication and improving long-term survival. The combination of lamivudine (LAM) plus HBIG has been for many years the most widely used. However, life-long HBIG use is both cumbersome and costly, whereas long-term use of LAM results in resistant virus. Recently, in an effort to develop HBIG-free protocols, high potency nucleos(t)ide analogues, such as Entecavir or Tenofovir, have been tried either as monotherapy or in combination with low-dose HBIG with excellent results. Current focus is on novel antiviral targets, especially for covalently closed circular DNA (cccDNA), in an effort to eradicate HBV infection instead of viral suppression. However, there are several other molecular mechanisms through which HBV may reactivate and need equal attention. The purpose of this review is to address post-LT HBV reactivation, its risk factors, underlying molecular mechanisms, and recent advancements and future of anti-viral therapy.

Prevention and Treatment of Recurrent Hepatitis B after Liver Transplantation

Chronic hepatitis B is a global health problem that leads to development of various complications, such as cirrhosis, liver cancer, and liver failure requiring liver transplantation. The recurrence of hepatitis B virus (HBV) post-liver transplantation is a major cause of allograft dysfunction, cirrhosis of the allograft, and graft failure. Patients with high viral load at the time of transplantation, hepatitis B e antigen (HBeAg) positivity, or those with a history of anti-viral drug resistance are considered as high-risk for recurrent HBV post-liver transplantation, while patients with low viral load, including HBeAg negative status, acute liver failure, and hepatitis D virus (HDV) co-infection are considered to be at low-risk for recurrent HBV post-liver transplantation. Antivirals for patients awaiting liver transplantation(LT) cause suppression of HBV replication and reduce the risk of recurrent HBV infection of the allograft and, therefore, all HBV patients with decompensated cirrhosis should be treated with potent antivirals with high genetic barrier to resistance (entecavir or tenofovir) prior to liver transplantation. Prevention of post-liver transplantation recurrence should be done using a combination of hepatitis B immunoglobulin (HBIG) and antivirals in patients at high risk of recurrence. Low dose HBIG, HBIG-free protocols, and monoprophylaxis with high potency antivirals can still be considered in patients at low risk of recurrence. Even, marginal grafts from anti-HBc positive donors can be safely used in hepatitis B surface antigen (HBsAg) negative, preferably in anti-hepatitis B core (HBc)/anti-hepatitis B surface (HBs) positive recipients. In this article, we aim to review the mechanisms and risk factors of HBV recurrence post-LT in addition to the various treatment strategies proposed for the prevention of recurrent HBV infection.

One-year extended, monthly vaccination prophylaxis combined with hepatitis B immune globulin for hepatitis B after liver transplantation

AIM

The feasibility of vaccination in liver transplant recipients is highly controversial, and the present study aimed to investigate the efficacy of a 1-year extended, monthly vaccine prophylaxis protocol of a second-generation recombinant vaccine for transplant recipients.

METHODS

The recombinant hepatitis B vaccine (10 µg) was administrated s.c. every month for 12 months as the vaccination protocol to 39 liver transplant recipients in stable condition, including those with hepatitis B-related chronic liver disease (n = 30), those with acute hepatitis B liver failure (hepatitis B surface antibody [HBsAb], n = 4), and those with hepatitis B core antibody positive grafts (n = 5). A fixed dose of hepatitis B immune globulin (HBIG) was administrated during the study based on the monoprophylaxis approach, and the increase in the hepatitis B surface antibody titer was measured to evaluate the efficacy of the vaccination.

RESULTS

The vaccination protocol was initiated a mean of 54 months (range, 13-124) after liver transplantation, and all patients tolerated the vaccination well without adverse effects. The overall hepatitis B virus (HBV) recurrence rate was 5% (2/39) based on hepatitis B surface antigen positivity, and 2% (1/39) based on HBV DNA detectability. Six (15%) patients showed a good response to vaccination with an increase in the HBsAb titer greater than 100 IU/L at the end of vaccination, but only three (8%) maintained an adequate HBsAb level to spare HBIG during the 2-year observation period.

CONCLUSION

While a few patients demonstrated an adequate response to vaccination, the clinical indication for the HBV vaccination for liver transplant recipients is currently minimal.

Recent advance of the hepatitis B virus inhibitors: a medicinal chemistry overview

Hepatitis B Virus (HBV) is one of the most prevalent viral infections of human worldwide. The therapies are limited in the clinical context because of negative side effects of interferons and the development of viral resistance to the nucleoside/nucleotide inhibitors. In this review, we summarize the recent advances in design and development of potent anti-HBV inhibitors from natural sources and synthetic compounds, targeting different steps in the life cycle of HBV. We attempt to emphasize the major structural modifications, mechanisms of action and computer-aided docking analysis of novel potent inhibitors that need to be addressed in the future to design potent anti-HBV molecules.

Late liver function test abnormalities post-adult liver transplantation: a review of the etiology, investigation, and management

Approximately 24,000 liver transplants are performed annually worldwide, almost 7000 of which are performed in the USA. Survival is excellent and continues to improve, with 1-year survival currently exceeding 85 %, but effective management of patients after liver transplantation is critical to achieve optimal results. A plethora of diseases can affect the transplanted allograft, ranging from recurrence of the original disease to de novo liver pathology, and diagnosis can be complicated by nonclassical presentation, de novo disease, or inconclusive histology. Patients can remain asymptomatic despite significant damage to the transplanted liver, so prompt identification and treatment of liver disease after transplantation is crucial to preserve allograft function. Liver function tests are routinely taken throughout the postoperative period to monitor the graft. Although nonspecific, they are inexpensive, noninvasive, and sensitive for allograft disease and can quickly alert physicians to the presence of asymptomatic pathology. This review will outline possible causes of liver function test abnormalities in the late posttransplant period and provide guidance for investigation, diagnosis, and management.

Application of nucleoside analogues to liver transplant recipients with hepatitis B

Hepatitis B is a common yet serious infectious disease of the liver, affecting millions of people worldwide. Liver transplantation is the only possible treatment for those who advance to end-stage liver disease. Donors positive for hepatitis B virus (HBV) core antibody (HBcAb) have previously been considered unsuitable for transplants. However, those who test negative for the more serious hepatitis B surface antigen can now be used as liver donors, thereby reducing organ shortages. Remarkable improvements have been made in the treatment against HBV, most notably with the development of nucleoside analogues (NAs), which markedly lessen cirrhosis and reduce post-transplantation HBV recurrence. However, HBV recurrence still occurs in many patients following liver transplantation due to the development of drug resistance and poor compliance with therapy. Optimized prophylactic treatment with appropriate NA usage is crucial prior to liver transplantation, and undetectable HBV DNA at the time of transplantation should be achieved. NA-based and hepatitis B immune globulin-based treatment regimens can differ between patients depending on the patients' condition, virus status, and presence of drug resistance. This review focuses on the current progress in applying NAs during the perioperative period of liver transplantation and the prophylactic strategies using NAs to prevent de novo HBV infection in recipients of HBcAb-positive liver grafts.

Tenofovir/entecavir monotherapy after hepatitis B immunoglobulin withdrawal is safe and effective in the prevention of hepatitis B in liver transplant recipients

BACKGROUND AND AIMS

Combination of hepatitis B immunoglobulin (HBIG) and a nucleos(t)ide analog (NA) is considered the standard of care for prophylaxis of hepatitis B virus (HBV) recurrence after liver transplantation (LT). However, use of lifelong HBIG has significant limitations. We evaluated the efficacy and safety of entecavir (ETV) or tenofovir disoproxil fumarate (TDF) after withdrawal of HBIG in patients who had been under HBIG-regimen prophylaxis post LT.

METHODS

Patients at low risk of recurrence were eligible for HBIG discontinuation (fulminant HBV hepatitis, co-infection with hepatitis D virus, and hepatitis B e antigen-negative cirrhotic patients with HBV DNA levels <300 copies/mL). All patients had received HBIG, with or without NA, for at least 12 months after LT. After HBIG discontinuation, they continued with ETV or TDF monotherapy. Patients were followed up with HBV serum markers and evaluation of renal function.

RESULTS

Between September 2011 and June 2014, 58 liver transplant recipients were converted to TDF (31, 53%) or ETV (27, 47%). Mean follow-up after conversion was 28 ± 5 months (range 13-36 months). Five patients (8.6%) developed detectable hepatitis B surface antigen at 7, 9, 13, 15, and 22 months after HBIG discontinuation. However, in every case seroconversion was transitory, serum HBV DNA was undetectable, with no clinical manifestations of HBV recurrence. No adverse effects were observed or dose reductions required associated with ETV or TDF.

CONCLUSIONS

Maintenance therapy with newer NAs, after discontinuation of HBIG prophylaxis, was safe and effective, with a low rate of serological recurrence and no evident clinical, biochemical, or virological consequences.

Change of strategies and future perspectives against hepatitis B virus recurrence after liver transplantation

A few decades ago, liver transplantation in patients with chronic hepatitis B virus (HBV) infection was considered a relative contraindication because of the high rate of graft infections and poor prognosis. Since then, remarkable progress was introduced by using nucleos(t)ide analogues and/or hepatitis B immunoglobulin (HBIg) and liver transplantation for HBV-related disease is now becoming one of the good indication. However, high cost burden is the main problem for this combination prophylaxis for a long time use, and this issue should be emerged to be resolved. In this review, we show the progress of post anti-HBV strategies showing the history from introduction of HBIg and nucleos(t)ide analogues to recent new strategies with hepatitis B vaccine or saving or stopping protocols of HBIg, and clarify and discuss how to do for further improvement of prevention strategies with better quality.

Telbivudine is associated with improvement of renal function in patients transplanted for HBV liver disease

Recent studies showed that telbivudine in patients with hepatitis B virus (HBV) infection improved their glomerular filtration rate (GFR), but data regarding its impact on renal function in liver transplant (LT) recipients are very limited. We evaluated 17 consecutive recipients who received at baseline nucleos(t)ide analogue(s) (NAs) other than telbivudine for 12 months, and then they were switched to telbivudine prophylaxis for another 12 months. In each patient, laboratory data including evaluation of GFR (using MDRD and CKD-EPI) were prospectively recorded. The changes in GFR (ΔGFR) between baseline and after 12 months (1st period) and between telbivudine initiation and 24 months (2nd period) were evaluated. All patients remained serum HBsAg and HBV-DNA negative. GFR-MDRD at baseline, 12 months and 24 months were 72 ± 18, 67.8 ± 16 and 70.3 ± 12 mL/min, respectively, (P = 0.025 for comparison between 12 months and 24 months). ΔGFR at the 1st period was significantly lower, compared with ΔGFR at the 2nd period [mean ΔGFR-MDRD: -4.2 (range: -24-9) vs 2.5 (range: -7-22) mL/min, P = 0.013; mean ΔGFR-CKD-EPI: -4.2 (range: -19-10) vs 4.0 (range: -7-23) mL/min, P = 0.004], although the serum levels of calcineurin inhibitors were similar between the two periods. A second group of recipients (n = 17) who remained under the same nontelbivudine NA(s) for 24 months had a decline in the mean eGFR during the total follow-up period. In conclusion, we showed that telbivudine administration in LT recipients for HBV cirrhosis was effective and it was associated with significant improvement in renal function, but this remains to be confirmed in larger well-designed studies.

Intravenous immunoglobulins in liver transplant patients: Perspectives of clinical immune modulation

Shortage of appropriate donor grafts is the foremost current problem in organ transplantation. As a logical consequence, waiting times have extended and pretransplant mortality rates were significantly increasing. The implementation of a priority-based liver allocation system using the model of end-stage liver disease (MELD) score helped to reduce waiting list mortality in liver transplantation (LT). However, due to an escalating organ scarcity, pre-LT MELD scores have significantly increased and liver recipients became more complex in recent years. This has finally led to posttransplant decreasing survival rates, attributed mainly to elevated rates of infectious and immunologic complications. To meet this challenging development, an increasing number of extended criteria donor grafts are currently accepted, which may, however, aggravate the patients’ infectious and immunologic risk profiles. The administration of intravenous immunoglobulins (IVIg) is an established treatment in patients with immune deficiencies and other antibody-mediated diseases. In addition, IVIg was shown to be useful in treatment of several disorders caused by deterioration of the cellular immune system. It proved to be effective in preventing hyperacute rejection in highly sensitized kidney and heart transplants. In the liver transplant setting, the administration of specific Ig against hepatitis B virus is current standard in post-LT antiviral prophylaxis. The mechanisms of action of IVIg are complex and not fully understood. However, there is increasing experimental and clinical evidence that IVIg has an immuno-balancing impact by a combination of immuno-supporting and immuno-suppressive properties. It may be suggested that, especially in the context of a worsening organ shortage with all resulting clinical implications, liver transplant patients should benefit from immuno-regulatory capabilities of IVIg. In this review, perspectives of immune modulation by IVIg and impact on outcome in liver transplant patients are described.

Accurate Detection of Hepatitis B Virus G1896A Mutant by Developed Taqman-ARMS Followed a Strict Control System

BACKGROUND

Hepatitis B virus (HBV) G1896A mutation was associated with HBeAg seronegativity and hepatitis B related acute-on-chronic liver failure. In this study, we developed Taqman amplification refractory mutation system (Taqman-ARMS) and established a strict control system to detect HBV G1896A mutant.

METHODS

HBV viral DNA was isolated from 60 patient serum samples, and full-length HBV genome was cloned. Then, Taqman-ARMS was used to detect HBV G1896A mutant.

RESULTS

The assay has the sensitivity of 1E+3 IU/ml G1896A template, and 0.1% weak population virus with G1896A could be found in mixtures. Total of all 60 clinical samples random collected were detected by Taqman-ARMS, the results were consistent with those by DNA sequencing.

CONCLUSION

The proposed Taqman-ARMS real-time PCR method for the detection of G1896A mutation of HBV was rapid, simple, sensitive, specific, and applicable in the clinical setting.

Intramuscular hepatitis B immunoglobulins for reinfection control after liver transplantation: a cost-saving alternative

Aim: We explore the effectiveness and cost–effectiveness of intramuscular versus intravenous hepatitis B immunoglobulins (HBIG-IV vs HBIG-IM) to prevent reinfection with the hepatitis B virus after orthotopic liver transplantation. Patients & methods: Overall, 14 patients had orthotopic liver transplantation in 2003–2013 at Ghent University Hospital for HBV-related liver disease. On average 32 months after transplantation patients switched from high-dose HBIG-IV to low-dose HBIG-IM, always in combination with a nucleos(t)ide analog. Results: Seven patients were switched so far. No significant differences between HBIG-IV and HBIG-IM were found in HBsAg and hepatitis B virus-DNA. Conclusion: Switching patients from HBIG-IV to HBIG-IM can be done safely if well monitored. Net yearly savings for the healthcare payer were €5000 for each patient switched to HBIG-IM.

Antiviral therapies for hepatitis B virus-related hepatocellular carcinoma

Chronic hepatitis B virus (HBV) infection is a critical risk factor for the carcinogenesis and progression of hepatocellular carcinoma (HCC). It promotes HCC development by inducing liver fibrogenesis, genetic and epigenetic alterations, and the expression of active viral-coded proteins. Effective antiviral treatments inhibit the replication of HBV, reduce serum viral load and accelerate hepatitis B e antigen serum conversion. Timely initiation of antiviral treatment is not only essential for preventing the incidence of HCC in chronic hepatitis B patients, but also important for reducing HBV reactivation, improving liver function, reducing or delaying HCC recurrence, and prolonging overall survival of HBV-related HCC patients after curative and palliative therapies. The selection of antiviral drugs, monitoring of indicators such as HBV DNA and hepatitis B surface antigen, and timely rescue treatment when necessary, are essential in antiviral therapies for HBV-related HCC.

Management of patients with hepatitis B in special populations

The development of effective nucleos(t)ide analogs (NAs) against hepatitis B virus (HBV) has improved the outcome of patients with chronic hepatitis B (CHB). This review updates issues related to the management of CHB patients included in special populations. Entecavir (ETV) and tenofovir (TDF) represent the currently recommended first-line NAs in patients with HBV decompensated cirrhosis. The combination of HBV immunoglobulin (usually for a finite duration) and NA is considered the standard of care for prophylaxis against HBV recurrence after liver transplantation. TDF is the best choice for hemodialysis patients and in patients with chronic kidney disease with nucleoside resistance. ETV and telbivudine are the preferred options in naïve renal transplant recipients and with low viremia levels, respectively. All hepatitis B surface antigen (HBsAg)-positive candidates should be treated with NAs before renal transplantation to achieve undetectable HBV DNA at the time of transplantation. Conventional interferon or NAs can also be used in children, on the basis of well-established therapeutic indication. Pregnant women at high risk of perinatal transmission could be treated with lamivudine, telbivudine or TDF in the last trimester of pregnancy. HBsAg-positive patients under immunosuppression should receive NA pre-emptively (regardless of HBV DNA levels) up to 12 mo after its cessation. In HBsAg negative, anti-HBc positive patients under immunosuppression, further studies are needed to form a final conclusion; however, it seems that anti-HBV prophylaxis is justified in such patients with hematological diseases and/or for those receiving rituximab-containing regimens, regardless of their anti-HBs or serum HBV DNA status.

Management of viral hepatitis in liver transplant recipients

Recurrence of viral hepatitis after liver transplantation (LT) can progress to graft failure and lead to a decrease in long-term survival. Recently, there have been remarkable improvement in the treatment of chronic hepatitis B (CHB) using potent antiviral agents. Combination of hepatitis B immunoglobulin and potent antiviral therapy has brought marked advances in the management of CHB for liver transplant recipients. Post-transplant antiviral therapy for hepatitis C virus infection is generally reserved for patients showing progressive disease. Acheiving a sustained virological response in patients with LT greatly ameliorates graft and overall survival, however this only occurs in 30% of transplant recipient using pegylated interferon and ribavirin (RBV). Direct acting antivirals such as protease inhibitors, polymerase or other non-structural proteins inhibitors are anticipated to establish the new standard of care for transplant recipients. In liver transplant recipients, hepatitis E virus infection is an uncommon disease. However, it can lead to chronic hepatitis and cirrhosis and may require retransplantation. Recently, 3-month course of RBV monotherapy has been reported as an effective treatment. This review focuses on the recent management and therapeutic approaches of viral hepatitis in liver transplant recipient.

Inhibitors of hepatitis B virus attachment and entry

Inhibition of virus entry has become a major concept in the development of new antiviral drugs. Entry inhibitors can either neutralize activities of viral surface proteins or target essential host factors such as (co)receptors. Due to its distinct tissue tropism and the highly specific viral and cellular factors involved in its entry, hepatitis B virus (HBV) is an ideal candidate for entry inhibition. Hepatitis B immunoglobulins neutralize infection by binding to the S-domain of HBV surface proteins and are used to prevent reinfection of the graft after liver transplantation. Novel S or preS-specific monoclonal antibodies are currently in development. The identification of sodium-taurocholate cotransporting polypeptide (NTCP) as a bona fide receptor has revealed a suitable target for HBV entry inhibition. NTCP receptor function is blocked by a variety of different agents including Myrcludex B, a synthetic N-acylated preS1-derived lipopeptide that inhibits HBV entry in vitro and in vivo with high efficacy. Current antiviral treatment for chronic HBV-infected patients focuses on the inhibition of the viral polymerase via nucleos(t)ide analogues (NA). Entry inhibitors in combination with NAs could block reinfection and shield naive hepatocytes that emerge from natural liver turnover, opening up new therapeutic options.

New nucleos(t)ide analogue monoprophylaxis after cessation of hepatitis B immunoglobulin is effective against hepatitis B recurrence

New nucleos(t)ide agents (NAs) [entecavir (ETV) and tenofovir (TDF)] have made hepatitis B immunoglobulin (HBIG)-sparing protocols an attractive approach against hepatitis B virus (HBV) recurrence after liver transplantation (LT). Twenty-eight patients transplanted for HBV cirrhosis in our centre were prospectively evaluated. After LT, each patient received HBIG (1000 IU IM/day for 7 days and then monthly for 6 months) plus ETV or TDF and then continued with ETV or TDF monoprophylaxis. All patients had undetectable HBV DNA at the time of LT, and they were followed up with laboratory tests including glomerular filtration rate (GFR) after LT. All patients (11 under ETV and 17 under TDF) remained HBsAg/HBV DNA negative during the follow-up period [median: 21 (range 9-43) months]. GFR was not different between TDF and ETV groups of patients at 6 and 12 months and last follow-up (P value >0.05 for all comparisons). The two groups of patients were similar regarding their ratio of maximum rate of tubular phosphate reabsorption to the GFR (TmP/GFR). In conclusion, in this prospective study, we showed for the first time that maintenance therapy with ETV or TDF monoprophylaxis after 6 months of low-dose HBIG plus ETV or TDF after LT is highly effective and safe.