Significant improvement in the outcome of HCV-infected transplant recipients by avoiding rapid steroid tapering and potent induction immunosuppression

Liver Transplantation from a Human Leukocyte Antigen-Matched Sibling Donor: Effectiveness of Direct-Acting Antiviral Therapy against Hepatitis C Virus Infection

Through living-donor liver transplantation (LDLT) from a human leukocyte antigen (HLA)-matched sibling donor, it may be possible to stop the use of immunosuppressants. It is possible that acute antibody-mediated rejection and chronic active antibody-mediated rejection through the positivity of donor-specific anti-HLA antibodies and/or T cell-mediated rejection may affect the prognosis of liver transplantation. The etiologies of liver diseases of the recipient may also affect the post-transplantation course. Herein, we report on the successful re-treatment with direct-acting antiviral (DAA) therapy against hepatitis C virus (HCV) infection in a patient who underwent a LDLT from HLA-matched sibling donor. After liver transplantation for HCV-related liver diseases, it is easy for HCV to re-infect the graft liver under a lack of immunosuppressants. DAA therapy against HCV re-infection immediately after transplantation should be commenced, and it is important to eradicate HCV for better prognosis of the recipients in LDLT for HCV-related liver diseases.

Immunosuppression in liver and intestinal transplantation

Immunosuppression handling plays a key role in the early and long-term results of transplantation. The development of multiple immunosuppressive drugs led to numerous clincial trials searching to reach the ideal regimen. Due to heterogeneity of the studied patient cohorts and flaws in many, even randomized controlled, study designs, the answer still stands out. Nowadays triple-drug immunosuppression containing a calcineurin inhibitor (preferentially tacrolimus), an antimetabolite (using mycophenolate moffettil or Azathioprine) and short-term steroids with or without induction therapy (using anti-IL2 receptor blocker or anti-lymphocytic serum) is the preferred option in both liver and intestinal transplantation. This chapter aims, based on a critical review of the definitions of rejection, corticoresistant rejection and standard immunosuppression to give some reflections on how to reach an optimal immunosuppressive status and to conduct trials allowing to draw solid conclusions. Endpoints of future trials should not anymore focus on biopsy proven, acute and chronic, rejection but also on graft and patient survival. Correlation between early- and long-term biologic, immunologic and histopathologic findings will be fundamental to reach in much more patients the status of operational tolerance.

Post liver transplant recurrent and de novo viral infections

Survival following liver transplantation has changed dramatically owing to improvement in surgical techniques, peri-operative care and optimal immunosuppressive therapy. Post-Liver transplant (LT) de novo or recurrent viral infection continues to cause major allograft dysfunction, leading to poor graft and patient survival in untreated patients. Availability of highly effective antiviral drugs has significantly improved post-LT survival. Patients transplanted for chronic hepatitis B infection should receive life-long nucleos(t)ide analogues, with or without HBIg for effective viral control. Patients with chronic hepatitis C should be commenced on directly acting antiviral (DAA) drugs prior to transplantation. DAA therapy for post-LT recurrent hepatitis C infection is associated with close to 100% sustained virological response (SVR), irrespective of genotype. De novo chronic Hepatitis E infection is an increasingly recognised cause of allograft dysfunction in LT recipients. Untreated chronic HEV infection of the graft may lead to liver fibrosis and allograft failure. CMV and EBV can reactivate leading to systemic illness following liver transplantation. With COVID-19 pandemic, post-transplant patients are at risk of SARS-Co-V2 infection. Majority of the LT recipients require hospitalization, and the mortality in this population is around 20%. Early recognition of allograft dysfunction and identification of viral aetiology is essential in the management of post-LT de novo or recurrent infections. Optimising immunosuppression is an important step in reducing the severity of allograft damage in the treatment of post-transplant viral infections. Viral clearance or control can be achieved by early initiation of high potency antiviral therapy.

Hepatitis C virus intrinsic molecular determinants may contribute to the development of cholestatic hepatitis after liver transplantation

Cholestatic hepatitis C (CHC) is a severe form of hepatitis C virus (HCV) infection recurrence that leads to high graft loss rates early after liver transplantation (LT). To investigate the pathogenic mechanisms of CHC, we analysed HCV quasispecies in CHC patients compared to a control group (mild hepatitis C recurrence) by deep pyrosequencing. At the time of LT, NS5B quasispecies complexity was similar between the two groups but, after LT, it decreased more sharply in CHC patients than in the control group. Interestingly, the major variant before LT propagated efficiently and remained as the dominant sequence after LT in 62 % of CHC patients versus 11 % of controls (P=0.031). Sequence analysis of the complete non-structural region in a limited number of patients revealed a potential 12 aa signature specific to the CHC group. These data suggest that intrinsic molecular determinants in the circulating HCV quasispecies may provide a fitness advantage, contributing to the development of CHC.

Incidence of Post-Liver Transplant Hepatic Dysfunction After Sustained Virologic Response Following Direct-Acting Anti-Hepatitis C Therapy

OBJECTIVES

Newly developed, direct-acting antiviral therapy is effective in over 90% of cases to eradicate hepatitis C virus infection. Direct-acting antiviral therapy is also effective in liver transplant recipients with recurrent hepatitis C virus infection. However, hepatic function after sustained virologic response in transplant recipients is unknown. Here, we aimed to uncover the incidence of hepatic dysfunction in this patient group at our center.

MATERIALS AND METHODS

Our study included 40 consecutive (January 2014 to February 2016) and compliant posttransplant recipients who achieved sustained viral response from direct-acting antiviral therapy. Patients were investigated for incidence and causes of hepatic dysfunction.

RESULTS

In our patient group, 4 (10%) experienced hepatic dysfunction with stable baseline immunosuppression, with 2 having drastic increases in alanine aminotransferase at 15 and 32 weeks after direct-acting antiviral therapy. Biopsies showed hepatitis, and both patients were treated with hydrocortisone, which increased their baseline immunosuppression. The 3rd patient had an increase in bilirubin at 21 weeks posttherapy, with biopsy showing macrovascular steatosis. The 4th patient had a rapid increase in bilirubin at 7 weeks after direct-acting antiviral therapy, with biopsy showing significant duct loss.

CONCLUSIONS

During the study period, 10% of patients experienced hepatic dysfunction after sustained viral response. Presumed causative factors included partial immune reconstitution and nonalcoholic fatty liver disease.

Management of Immunosuppression in Liver Transplantation

Liver transplantation outcomes have significantly improved over the past few decades owing largely to the introduction of effective immunosuppression medications. Further comprehension of the unique immune microenvironment of the liver has led to the development of newer molecular targeted therapeutics. Understanding the mechanism of action and adverse effect profiles of these medications is crucial for appropriate management of posttransplant patients. In this review, the author describes the immunologic response elicited by liver transplantation, chronicles the various immunosuppressant drug classes, discusses the evidence behind their use, and evaluates the management of special subpopulations of posttransplantation patients.

Fibrosing cholestatic hepatitis C in post-transplant adult recipients of liver transplantation

Hepatitis C recurrence continues to present a major challenge in liver transplantation (LT). Approximately 10% of hepatitis C virus (HCV)-positive recipients will develop fibrosing cholestatic hepatitis (FCH) after LT. FCH is clinically characterized as marked jaundice with cholestatic hepatic dysfunction and high titers of viremia. Pathologically, FCH manifests as marked hepatocyte swelling, cholestasis, periportal peritrabecular fibrosis and only mild inflammation. This progressive form usually involves acute liver failure, and rapidly results in graft loss. A real-time and precise diagnosis based on histopathological examination and viral measurement is indispensable for the adequate treatment of FCH. Typical pathological findings of FCH are shown. Currently, carefully selected combinations of direct-acting antivirals (DAAs) offer the potential for highly effective and safe regimens for hepatitis C, both in the pre- and post-transplant settings. Here, we review FCH caused by HCV in LT recipients, and current strategies for sustained virological responses after LT. Only a few cases of successfully treated FCH C after LT by DAAs have been reported. The diagnostic findings and therapeutic dilemma are discussed based on a literature review.

Management of post liver transplantation recurrent hepatitis C infection with directly acting antiviral drugs: a review

Recurrent HCV infection (rHCV) of the liver allograft following transplantation is universal and is associated with poor graft and patient survival in comparison with other indications. Treatment of rHCV infection in the previous era with pegylated interferon and ribavirin was associated with low sustained virological response (SVR) due to poor tolerability, adverse events and graft rejection. Recently, directly acting antiviral drugs (DAA) have been approved for the treatment of hepatitis C infection and a number of clinical trials have been conducted across various centers in the management of rHCV infection of the graft. In this review we discuss about recent studies that have emerged on the use of NS5b polymerase inhibitor, sofosbuvir in combination with second generation protease inhibitor, simeprevir, fixed dose ledipasvir or daclatasvir with or without ribavirin in the treatment of post transplant rHCV infection.

Prednisolone does not affect direct-acting antivirals against hepatitis C, but inhibits interferon-alpha production by plasmacytoid dendritic cells

BACKGROUND

Chronic hepatitis C virus (HCV) infection compromises long-term outcomes of liver transplantation. Although glucocorticosteroid-based immunosuppression is commonly used, discussion is ongoing on the effect of prednisolone (Pred) on HCV recurrence and response to antiviral therapy post transplantation. Recently, new drugs (direct-acting antivirals) have been approved for the treatment of HCV, however, it remains unknown whether their antiviral activity is affected by Pred. The aim of this study was to investigate the effects of Pred on the antiviral activity of asunaprevir (Asu), daclatasvir (Dac), ribavirin (RBV), and interferon-alpha (IFN-α), and on plasmacytoid dendritic cells (PDCs), the main IFN-α-producing immune cells.

METHODS

The effects of Pred and antiviral compounds were tested in both a subgenomic and infectious HCV replication model. Furthermore, effects were tested on human PDCs stimulated with a Toll-like receptor-7 ligand.

RESULT

Pred did not directly affect HCV replication and did not inhibit the antiviral action of Asu, Dac, RBV, or IFN-α. Stimulated PDCs potently suppressed HCV replication. This suppression was reversed by treating PDCs with Pred. Pred significantly decreased IFN-α production by PDCs without affecting cell viability. When Asu and Dac were combined with PDCs, a significant cooperative antiviral effect was observed.

CONCLUSION

This study shows that Pred acts on the antiviral function of PDCs. Pred does not affect the antiviral action of Asu, Dac, RBV, or IFN-α. This implies that there is no contraindication to combine antiviral therapies with Pred in the post-transplantation management of HCV recurrence.

Management of Hepatitis C Post-liver Transplantation: a Comprehensive Review

Infection with hepatitis C virus (HCV) is a common cause of chronic liver disease, and HCV-related cirrhosis and hepatocellular carcinoma are the leading causes for liver transplantation in the Western world. Recurrent infection of the transplanted liver allograft is universal in patients with detectable HCV viremia at the time of transplant and can cause a spectrum of disease, ranging from asymptomatic chronic infection to an aggressive fibrosing cholestatic hepatitis. Recurrent HCV is more aggressive in the post-transplant population and is a leading cause of allograft loss, morbidity, and mortality. Historically, treatment of recurrent HCV has been limited by low rates of treatment success and high side effect profiles. Over the past few years, promising new therapies have emerged for the treatment of HCV that have high rates of sustained virological response without the need for interferon based regimens. In addition to being highly effective, these treatments have higher rates of adherence and a lower side effect profile. The purpose of this review is to summarize current therapies in recurrent HCV infection, to review the recent advances in therapy, and to highlight areas of ongoing research.

Acute cellular rejection versus recurrent hepatitis C after liver transplantation: Clinical and pathological features driving a rational diagnostic approach

AIM

The aim of our study was develop and validate an algorithm system based on morphological features for finding the differences between recurrent hepatitis C virus (HCV) and acute cellular rejection (ACR) in liver biopsies of HCV-transplanted patients.

METHODS

Two hundred and eighty-eight liver biopsies were analyzed from 121 patients transplanted for HCV. A diagnostic consensus was reached between clinicians and pathologists in 214 biopsies for the diagnosis of recurrent HCV or ACR. A random sample of 114 liver biopsies (derivation cohort) was taken to generate the diagnostic tree and was subsequently evaluated using the validation cohort in 100 liver biopsies by recursive partitioning analysis of morphological variables and time since transplantation.

RESULTS

The presence of endotheliitis together with a time of less than 6 weeks since LT definitely excluded recurrent HCV. After obtaining the regression tree, diagnostic accuracy was 96% and 93% in the derivation and validation cohort, respectively. Both cases surpassed the pathologist's original diagnosis, which had a diagnostic accuracy of 91% (P < 0.05, for both comparisons).

CONCLUSION

A recursive partitioning analysis of the morphological features in liver biopsies from HCV-transplanted patients may be useful for easily distinguishing between recurrent HCV and ACR.

Management of post transplant hepatitis C in the direct antiviral agents era

Hepatitis C virus (HCV) infection is one of the main indications for liver transplantation. Viral recurrence occurs in all patients with detectable serum HCV RNA at the time of transplantation leading to cirrhosis in 20-30% of patients within 5 years. Viral eradication using antiviral therapy has been shown to improve patient and graft survival. Pegylated interferon (PEG-IFN) and ribavirin (RBV) antiviral therapy achieved SVR in around 30% of transplant recipients. In the non-transplant setting, first generation NS3/4 protease inhibitors, boceprevir or telaprevir associated with PEG-IFN and RBV, has improved the SVR rates to 75% in genotype 1 infected patients. However, tolerability and drug-drug interactions with calcineurin inhibitors are both limiting factors of their use in transplant recipients. In the non-transplant patients, using new direct-acting antiviral therapy has dramatically improved the efficacy of antiviral C therapy over recent years leading to SVR rates over 90% in phase II and III clinical trials, without PEG-IFN and/or RBV. Preliminary results in transplant patients showed better efficacy, better tolerability and less drug-drug interactions.

Management of recurrent hepatitis C virus after liver transplantation

Chronic hepatitis C virus (HCV) infection is the leading cause of death from liver disease and the leading indication for liver transplantation (LT) in the United States and Western Europe. LT represents the best therapeutic alternative for patients with advanced chronic liver disease caused by HCV or those who develop hepatocarcinoma. Reinfection by HCV of the graft is universal and occurs in 95% of transplant patients. This reinfection can compromise graft function and patient survival. In a few cases, the histological recurrence is minimal and non-progressive; however, in most patients it follows a more rapid course than in immunocompetent persons, and frequently evolves into cirrhosis with graft loss. In fact, the five-year and ten-year survival of patients transplanted because of HCV are 75% and 68%, respectively, compared with 85% and 78% in patients transplanted for other reasons. There is also a pattern of recurrence that is very severe, but rare (< 10%), called fibrosing cholestatic hepatitis, which often involves rapid graft loss. Patients who present a negative HCV viremia after antiviral treatment have better survival. Many studies published over recent years have shown that antiviral treatment of post-transplant HCV hepatitis carried out during the late phase is the best option for improving the prognosis of these patients. Until 2011, PEGylated interferon plus ribavirin was the standard of care, resulting in a sustained virological response in around 30% of recipients. The addition of protease inhibitors, such as boceprevir or telaprevir, to the standard of care, or the use of other direct-acting antiviral drugs may involve therapeutic changes in the context of HCV recurrence. This may result a better prognosis for these patients, particularly those with severe recurrence or factors predicting rapid progression of fibrosis. However, the use of these agents in LT still requires clarification in terms of safety and efficacy.

Natural history, treatment and prevention of hepatitis C recurrence after liver transplantation: Past, present and future

Hepatitis C virus (HCV)-related liver disease, including cirrhosis and hepatocellular carcinoma is the main indication for liver transplantation (LT) worldwide. Post-transplant HCV re-infection is almost universal and results in accelerated progression from acute hepatitis to chronic hepatitis, and liver cirrhosis. Comprehension and treatment of recurrent HCV infection after LT have been major issues for all transplant hepatologists and transplant surgeons for the last decades. The aim of this paper is to review the evolution of our knowledge on the natural history of HCV recurrence after LT, including risk factors for disease progression, and antiviral therapy. We will focus our attention on possible ways (present and future) to improve the final long-term results of LT for HCV-related liver disease.

Hepatitis viruses and liver transplantation: evolving trends in antiviral management

Viral hepatitis is both a leading indication for liver transplant (LT) and an important cause of posttransplant graft loss and mortality. Treatment and prevention of hepatitis B virus in LT recipients, with the observed corresponding improvement in post-LT outcomes, is among the great success stories in transplantation. By comparison, treatment of hepatitis C virus with safe and effective regimens is only just becoming a reality. Chronic hepatitis E virus infection in LT recipients represents a newly described phenomenon that can also lead to graft loss; early diagnosis and treatment may be key in the management of these patients.

Challenges of recurrent hepatitis C in the liver transplant patient

Cirrhosis secondary to hepatitis C virus (HCV) is a very common indication for liver transplant. Unfortunately recurrence of HCV is almost universal in patients who are viremic at the time of transplant. The progression of fibrosis has been shown to be more rapid in the post-transplant patients than in the transplant naïve, hence treatment of recurrent HCV needs to be considered for all patients with documented recurrent HCV. Management of recurrent HCV is a challenging situation both for patients and physicians due to multiple reasons as discussed in this review. The standard HCV treatment with pegylated interferon and Ribavarin can be considered in these patients but it leads to a lower rate of sustained virologic clearance than in the non-transplanted population. Some of the main challenges associated with treating recurrent HCV in post-transplant patients include the presence of cytopenias; need to monitor drug-drug interactions and the increased incidence of renal compromise. In spite of these obstacles all patients with recurrent HCV should be considered for treatment since it is associated with improvement in survival and a delay in fibrosis progression. With the arrival of direct acting antiviral drugs there is renewed hope for better outcomes in the treatment of post-transplant HCV recurrence. This review evaluates current literature on this topic and identifies challenges associated with the management of post-transplant HCV recurrence.

Management of HCV transplant patients with triple therapy

Hepatitis C virus (HCV) infection is one of the leading causes of end-stage liver disease and the main indication for liver transplantation (LT) in most countries. All patients who undergo LT with detectable serum HCV RNA experience graft reinfection. Between 20 and 30% of patients have developed cirrhosis at 5 years post-LT. The outcome of transplant patients with cirrhosis on the graft is severe, with a rate of decompensation at 1 year of approximately 40%. To date, retransplantation is the only option in patients with decompensated liver disease. Until 2011, standard antiviral therapy with pegylated interferon (PEG-IFN) and ribavirin (RBV), was the only effective therapy. Obtaining a sustained virological response (SVR) in patients with LT greatly improves overall and graft survival but this only occurs in 30% of transplanted patients. Direct acting antivirals (DAAs) such as protease inhibitors (PI), polymerase or other non-structural proteins inhibitors represent a new era in HCV associated liver disease. Although their use in the field of LT will certainly be essential there are some limitations because of safety and tolerance. One limitation is the potential interaction with calcineurin inhibitors. We describe the results of triple therapy with boceprevir (BOC) or telaprevir (TVR) for efficacy and safety and comment on future therapeutic strategies in liver transplant recipients.

Immunosuppression minimization vs. complete drug withdrawal in liver transplantation

Despite the increase in long-term survival, liver transplant recipients still exhibit higher morbidity and mortality than the general population. This is in part attributed to the lifelong administration of immunosuppression and its associated side effects. Several studies reported in the last decades have evaluated the impact of immunosuppression minimization in liver transplant recipients, but results have been inconsistent due to the heterogeneity of study designs and insufficient sample sizes. On the other hand, complete immunosuppression withdrawal has proven to be feasible in approximately 20% of carefully selected liver transplant recipients, especially in older patients and those with longer duration after transplantation. The long-term risks and clinical benefits of this strategy, however, also need to be clarified. As a consequence, and despite the general perception that a large proportion of liver recipients are over-immunosuppressed, it is currently not possible to derive evidence-based guidelines on how to manage long-term immunosuppression to improve clinical outcomes. Large clinical trials of drug minimization and/or withdrawal focused on clinically-relevant long-term outcomes are required. Development of personalized medicine tools and a deeper understanding of the pathogenesis of idiopathic inflammatory graft lesions will be pre-requisites to achieve these goals.

Current status of immunosuppression in liver transplantation

With advancements in immunosuppressive strategies and availability of better immunosuppressive agents, survival rate following liver transplantation has improved significantly in the recent times. Besides improvements in surgical techniques, the most important factor that has contributed to this better outcome is the progress made in the field of immunosuppression. Over the last several years, the trend has changed to tailored immunosuppression with the aim of achieving optimal graft function while avoiding its undesirable side effects. Induction agents are no longer used routinely and the aim is to provide minimal immunosuppression in the maintenance phase. The present review discusses the various types of immunosuppressive agents, their mechanism of action, clinical utility, advantages and disadvantages, and their side effects in short and long-term. It also discusses about tailoring immunosuppression in presence of various situations such as renal dysfunction, metabolic syndrome, hepatitis C recurrence, cytomegalovirus infections and so on. The issue of chronic kidney disease and the available renal sparing immunosuppressive strategies has been particularly stressed upon. Finally, it discusses about the practical aspects of various immunosuppression regimens including drug monitoring.

Strategies to reduce hepatitis C virus recurrence after liver transplantation

Hepatitis C virus (HCV) is a major health problem that leads to chronic hepatitis, cirrhosis and hepatocellular carcinoma, being the most frequent indication for liver transplantation in several countries. Unfortunately, HCV re-infects the liver graft almost invariably following reperfusion, with an accelerated history of recurrence, leading to 10%-30% of patients progressing to cirrhosis within 5 years of transplantation. In this sense, some groups have even advocated for not re-transplanting this patients, as lower patient and graft outcomes have been reported. However, the management of HCV recurrence is being optimized and several strategies to reduce post-transplant recurrence could improve outcomes, decrease the rate of re-transplantation and optimize the use of available grafts. Three moments may be the focus of potential actions in order to decrease the impact of viral recurrence: the pre-transplant moment, the transplant environment and the post-transplant management. In the pre-transplant setting, it is not well established if reducing the pre transplant viral load affects the risk for HCV progression after transplant. Obviously, antiviral treatment can render the patient HCV RNA negative post transplant but the long-term benefit has not yet been fully established to justify the cost and clinical risk. In the transplant moment, factors as donor age, cold ischemia time, graft steatosis and ischemia/reperfusion injury may lead to a higher and more aggressive viral recurrence. After the transplant, discussion about immunosuppression and the moment to start the treatment (prophylactic, pre-emptive or once-confirmed) together with new antiviral drugs are of interest. This review aims to help clinicians have a global overview of post-transplant HCV recurrence and strategies to reduce its impact on our patients.

Management practices of hepatitis C virus infected alcoholic hepatitis patients: A survey of physicians

AIM: To survey gastroenterologists and hepatologists regarding their current views on treating hepatitis C virus (HCV) infected alcoholic hepatitis (AH) patients.

METHODS: A sixteen item questionnaire was electronically mailed to gastroenterologists and hepatologists. A reminder was sent after 2 mo to increase the response rate. Participation of respondents was confidential. Accessing secured web site to respond to the questionnaire was considered as informed consent. Responses received on the secured website were downloaded in an excel sheet for data analysis.

RESULTS: Analyzing 416 responses to 1556 (27% response rate) emails, 57% respondents (56% gastroenterologists) reported HCV prevalence > 20% amongst AH patients. Sixty nine percent often treated AH and 46% preferred corticosteroids (CS). Proportion of respondents with consensus (75% or more respondents agreeing on question) on specific management of HCV infected AH were: routine HCV testing (94%), HCV not changing response to CS (80%) or pentoxifylline (91%), no change in approach to treating HCV infected AH (75%). None of respondent variables: age, specialty, annual number of patients seen, and HCV prevalence could predict respondent to be in consensus on any of or all 4 questions. Further, only 4% would choose CS for treating HCV infected AH as opposed to 47% while treating HCV negative AH.

CONCLUSION: Gastroenterologists and hepatologists believe that AH patients be routinely checked for HCV. However, there is lack of consensus on choice of drug for treatment and outcome of HCV positive AH patients. Studies are needed to develop guidelines for management of HCV infected AH patients.

Management of recurrent hepatitis C in orthotopic liver transplant recipients

End-stage liver disease and hepatocellular carcinoma from chronic hepatitis C are the most common indications for orthotopic liver transplantation and the incidence of both are projected to increase over the next decade. Recurrent hepatitis C virus infection of the allograft is associated with an accelerated progression to cirrhosis, graft loss, and death. This article presents an overview of the natural history of hepatitis C virus recurrence in liver transplant recipients and guidance on optimal management strategies.

Immunomodulating options for liver transplant patients

Much has changed since the early years of liver transplantation. Improvements in post-transplant survival are largely due to more selective and less toxic immunosuppression regimens and advances in operative and perioperative care. This has allowed liver transplantation to become an extremely successful treatment option for patients with endstage liver disease. Beginning with cyclosporine, a cyclic endecapeptide of fungal origin and the first of the calcineurin inhibitors to find widespread use, immunosuppressive regimens have evolved to include additional calcineurin inhibitors, steroids, mTOR inhibitors, antimetabolites and antibodies, mostly targeting T-cell activation. This review will present currently available immunosuppressive agents used in the perioperative period of liver transplantation, as well as maintenance treatments, tailoring therapeutic strategies for specific populations, and advances in immune monitoring and tolerance.

Current management and perspectives for HCV recurrence after liver transplantation

Hepatitis C virus (HCV) infection is one of the leading causes of end-stage liver disease and the main indication for liver transplantation (LT) in most countries. All patients who undergo LT with detectable serum HCV RNA experience graft reinfection. Between 20 and 30% of patients develop cirrhosis within 5 years post-LT. The outcome of transplant patients with cirrhosis on the graft is severe, with a rate of decompensation at 1 year of around 40%. To date, retransplantation is the only option for patients who develop decompensation. Until 2011, standard antiviral therapy, using pegylated interferon (PEG-IFN) and ribavirin (RBV), was the only effective therapy. Obtaining a sustained virological response (SVR) in the setting of LT greatly improves overall and graft survival, but this only concerns 30% of transplanted patients. Direct-acting antivirals (DAA) such as protease inhibitors, polymerase or other non-structural proteins inhibitors represent a new era in HCV-associated liver disease. Although their use in the field of liver transplantation seems to be essential, there are some limitations due to safety and tolerance. One limitation is the potential interaction with calcineurin inhibitors. We describe the preliminary results of triple therapy with boceprevir or telaprevir in terms of efficacy and safety in liver transplant recipients.

Living-donor liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompression. In areas with low deceased-donor organ availability like Japan, living-donor liver transplantation (LDLT) is similarly indicated for HCV cirrhosis as deceased-donor liver transplantation (DDLT) in Western countries and accepted as an established treatment for HCV-cirrhosis, and the results are equivalent to those of DDLT. To prevent graft failure due to recurrent hepatitis C, antiviral treatment with pegylated-interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. In contrast to DDLT, many Japanese LDLT centers have reported modified treatment regimens as best efforts to secure first graft, such as aggressive preemptive antiviral treatment, escalation of dosages, and elongation of treatment duration.

Importance of liver biopsy findings in immunosuppression management: biopsy monitoring and working criteria for patients with operational tolerance

Obstacles to morbidity-free long-term survival after liver transplantation (LT) include complications of immunosuppression (IS), recurrence of the original disease and malignancies, and unexplained chronic hepatitis and graft fibrosis. Many programs attempt to minimize chronic exposure to IS by reducing dosages and stopping steroids. A few programs have successfully weaned a highly select group of recipients from all IS without apparent adverse consequences, but long-term follow-up is limited. Patients subjected to adjustments in IS are usually followed by serial liver chemistry tests, which are relatively insensitive methods for detecting allograft damage. Protocol biopsy has largely been abandoned for hepatitis C virus-negative recipients, at least in part because of the inability to integrate routine histopathological findings into a rational clinical management algorithm. Recognizing a need to more precisely categorize and determine the clinical significance of findings in long-term biopsy samples, the Banff Working Group on Liver Allograft Pathology has reviewed the literature, pooled the experience of its members, and proposed working definitions for biopsy changes that (1) are conducive to lowering IS and are compatible with operational tolerance (OT) and (2) raise concern for closer follow-up and perhaps increased IS during or after IS weaning. The establishment of guidelines should help us to standardize analyses of the effects of various treatments and/or weaning protocols and more rigorously categorize patients who are assumed to show OT. Long-term follow-up using standardized criteria will help us to determine the consequences of lowering IS and to define and determine the incidence and robustness of OT in liver allografts.

Hepatitis C virus recurrence and immunosuppression-free state after liver transplantation

HCV-related disease is the most common indication for liver transplantation (LT). HCV recurrence, which is almost universal, has a significant impact on patient and graft survival after LT and still represents a great unsolved issue for the liver transplant community. Several treatment strategies have been proposed. Since antiviral therapy has limited efficacy and can be administrated only in selected transplant recipients and additionally that immunosuppressive drugs have a negative impact on HCV re-infection, the achievement of an immunosuppression-free state after LT could play a central role in the avoidance of rapid HCV recurrence.

Prevention of hepatitis C recurrence after liver transplantation: An update

Hepatitis C related liver failure and hepatocarcinoma are the most common indications for liver transplantation in Western countries. Recurrent hepatitis C infection of the allograft is universal and immediate following liver transplantation, being associated with accelerated progression to cirrhosis, graft loss and death. Graft and patient survival is reduced in liver transplant recipients with recurrent Hepatitis C virus (HCV) infection compared to HCV-negative recipients. Many variables may impact on recurrent HCV liver disease. Overall, excess immunosuppression is believed to be a key factor; however, no immunosuppressive regimen has been identified to be more beneficial or less harmful. Donor age limitations, exclusion of moderately to severely steatotic livers and minimization of ischemic times could be a potential strategy to minimize the severity of HCV disease in transplanted subjects. After transplantation, antiviral therapy based on pegylated IFN alpha with or without ribavirin is associated with far less results than that reported for immunocompetent HCV-infected patients. New findings in the field of immunotherapy and genomic medicine applied to this context are promising.

HCV in liver transplantation

HCV-related cirrhosis represents the leading indication for liver transplantation in the Western countries. HCV reinfection after liver transplantation occurs in virtually all patients transplanted for HCV-related liver disease Histological evidence of chronic HCV infection develops in 50 to 90 % of patients by 12 months after liver transplantation, and cirrhosis occurs in about 20 % of patients within 5 years after transplant. Several studies have evaluated host, viral, and transplant-related factors that might be associated with the severity of HCV recurrence. Among host factors, immunosuppression is one of the major factors that accounts for accelerated HCV recurrence and it has been an area of extensive research and controversy. Donor age, steatosis, and immunogenetic factors are also relevant in determining the outcome in patients transplanted for HCV-related cirrhosis. A major step to prevent complications of HCV recurrence related to the rapid fibrosis is the posttransplant antiviral treatment. Two strategies have been tried: pre-emptive or other strategies as soon as possible after liver transplantation or elective therapy once there is histological evidence of recurrent hepatitis C. Retransplantation due to graft failure from recurrent hepatitis C is rarely an option in the era of organ shortage as it is associated with poor outcome, but many case needs to be considered early in the evolution of disease. New antivirals may change the outcome dramatically of patients transplanted for HCV cirrhosis.

A plant-derived flavonoid inhibits entry of all HCV genotypes into human hepatocytes

BACKGROUND & AIMS

Interferon-based therapies for hepatitis C virus (HCV) infection are limited by side effects and incomplete response rates, particularly among transplant recipients. We screened a library of plant-derived small molecules to identify HCV inhibitors with novel mechanisms.

METHODS

We isolated phenolic compounds from Marrubium peregrinum L (Lamiaceae). Replication of HCV RNA, virus production, and cell entry were monitored using replicons and infectious HCV. Inhibition of HCV was measured in hepatoma cells and primary human hepatocytes using luciferase reporter gene assays, core enzyme-linked immunosorbent assays, or infectivity titration. We tested the bioavailability of the compound in mice.

RESULTS

We identified a flavonoid, ladanein (BJ486K), with unreported antiviral activity and established its oral bioavailability in mice. Natural and synthetic BJ486K inhibited a post-attachment entry step, but not RNA replication or assembly; its inhibitory concentration 50% was 2.5 μm. BJ486K was effective against all major HCV genotypes, including a variant that is resistant to an entry inhibitor; it prevented infection of primary human hepatocytes. Combined administration of BJ486K and cyclosporine A had a synergistic effect in inhibition of HCV infection.

CONCLUSIONS

BJ486K has oral bioavailability and interferes with entry of HCV into cultured human hepatocytes. It synergizes with cyclosporine A to inhibit HCV infection. Its inhibitory effects are independent of HCV genotype, including a variant that is resistant to an entry inhibitor against scavenger receptor class B type I. Flavonoid derivatives therefore might be developed as components of combination therapies because they are potent, broadly active inhibitors of HCV entry that could prevent graft reinfection after liver transplantation.

Impact of donor histology on survival following liver transplantation for chronic hepatitis C virus infection: a Scandinavian single-center experience

OBJECTIVE

Survival following liver transplantation for hepatitis C virus (HCV) infection is affected by several factors. The aims of this single-center study were to evaluate survival from 1992 to 2006 in HCV-infected liver transplant recipients and to identify factors influencing patient and graft survival, with particular focus on donor liver histopathology.

MATERIAL AND METHODS

Survival among 84 patients transplanted for HCV-related liver disease at the Sahlgrenska University Hospital during the above period was evaluated. Median follow-up time was 57 months (range 28-87). A perioperative liver biopsy from the donor liver graft was available in 68 cases. Biopsies were assessed for fibrosis, necroinflammatory activity, and degree of steatosis. Patient and graft survival according to relevant factors including donor histopathology were analyzed by Kaplan-Meier analysis.

RESULTS

We found an association between donor liver fibrosis and patient survival (p = 0.016) as well as between graft survival and portal inflammation in the donor liver (p = 0.026). Both these associations remained significant in multivariate analysis (p = 0.007 and 0.017 respectively). Moreover, recipient age over 60 was found predictive of patient survival and repeated steroid boluses or steroid-resistant rejection of graft survival. Donor age was high throughout the study period.

CONCLUSION

Histopathological features, especially portal inflammation and stage of fibrosis, in the donor liver may deleteriously affect graft and patient survival following HCV-related liver transplantation. Thus, pretransplant evaluation of donor histopathology may be of value in the selection of donors for transplantation of HCV-positive individuals, especially among donors older than 60 years.

[Liver transplantation: personalized immunosuppression in patients with hepatitis C virus infection and hepatocellular carcinoma]

Transplantation has become the treatment of choice in end-stage liver disease, with 5-year survival rates of around 68-74% in European and North-American registries (www.unos.org, www.eltr.org, www.ont.es). These results are largely due to the development of powerful immunosuppressive agents, mainly calcineurin inhibitors. However, these immunosuppressive drugs are not free of adverse effects, especially nephrotoxicity. Moreover, two of the most frequent indications for transplantation, cirrhosis due to hepatitis C virus and hepatocellular carcinoma, can recur in the transplanted graft. Whether specific immunosuppression could be less harmful in these conditions is the subject of debate. With the greater use of suboptimal donors and of expanded criteria for liver transplantation in patients with hepatocellular carcinoma, aggressive recurrences can be expected to increase. The present review attempts to elucidate whether there is an immunosuppression strategy that could minimize the risk of aggressive tumoral recurrence or recurrence of hepatitis C.

Risk for immune-mediated graft dysfunction in liver transplant recipients with recurrent HCV infection treated with pegylated interferon

BACKGROUND & AIMS

Patients with recurrent hepatitis C virus infection treated with pegylated interferon (PEG) after liver transplantation can develop severe immune-mediated graft dysfunction (IGD) characterized by plasma cell hepatitis or rejection.

METHODS

We conducted a multicenter case-control study of 52 liver transplant recipients with hepatitis C to assess the incidence of, risk factors for, and outcomes of PEG-IGD. Data from each patient were compared with those from 2 matched patients who did not develop PEG-IGD (n = 104). We performed a multivariate analysis of risk factors and analyzed treatment and outcomes of graft dysfunction subtypes.

RESULTS

Overall incidence of PEG-IGD during a 10-year study period was 7.2%. Risk factors included no prior PEG therapy (odds ratio = 5.3; P < .0001), therapy with PEGα-2a (odds ratio = 4.7; P = .03), and immune features (mainly plasma cell hepatitis) on pre-PEG therapy liver biopsies (odds ratio = 3.9; P = .005). The PEG-IGD group had lower long-term patient (61.5% vs 91.3% of controls) and graft (38.5% vs 85.6% of controls) survival and higher rates of retransplantation (34.6% vs 6.7% of controls) (all, P < .0001), without increases in sustained virologic response. Variables associated with increased mortality included acute rejection as the PEG-IGD sub-type (hazard ratio [HR] = 2.4; P = .002), a high level of alkaline phosphatase at PEG initiation (HR = 1.003; P = .005), and lack of a sustained virologic response (HR = 3.3; P = .04). Variables associated with graft failure included a high level of alkaline phosphatase at PEG initiation (HR = 1.002; P = .04) and lack of a sustained virologic response (HR = 2.1; P = .04).

CONCLUSIONS

PEG-IGD has high morbidity and mortality and is not associated with increased rates of virologic response. It is important to avoid PEG therapy in liver transplant recipients with specific clinical, biochemical, and histologic risk factors for PEG-IGD.

Spanish society of liver transplantation (SETH) consensus recommendations on hepatitis C virus and liver transplantation

In November 2010, the Spanish Society of Liver Transplantation (Sociedad Española de Trasplante Hepático, SETH) held a consensus conference. One of the topics of debate was liver transplantation in patients with hepatitis C. This document reviews (i) the natural history of post-transplant hepatitis C, (ii) factors associated with post-transplant prognosis in patients with hepatitis C, (iii) the role of immunosuppression in the evolution of recurrent hepatitis C and response to antiviral therapy, (iv) antiviral therapy, both before and after transplantation, (v) follow-up of patients with recurrent hepatitis C and (vi) the role of retransplantation.

Immunosuppression and HCV recurrence after liver transplantation

HCV related liver disease is the most common indication for liver transplantation. Recurrence of HCV infection is universal and has a substantial impact on patient and graft survival. Immunosuppression is a major factor responsible for the accelerated recurrence and compressed natural history of recurrent HCV infection. Accumulating experience has provided data to support certain strategies for immunosuppressive regimens. From the available evidence, more severe recurrence results from repeated bolus corticosteroid therapy and anti-lymphocyte antibodies used to treat rejection. Low dose and slow tapering of steroids are better than high dose maintenance and/or rapid tapering. Recent meta-analyses favour steroid-free regimens but these are complicated to interpret as the absence of steroids may simply represent less immunopotency. There is no difference in HCV recurrence between tacrolimus and cyclosporine regimens, but tacrolimus increases graft and patient survival in HCV transplanted patients. There may be a beneficial effect of maintenance azathioprine given for 6 months or longer. There is no conclusive evidence for benefit of mycophenolate and interleukin-2 receptor blockers. Few data are available for mTOR inhibitors. Better evidence is needed to establish the optimal immunosuppressive regimen for HCV recipients and more randomized trials should be performed.

Hepatitis C virus viral kinetics during α-2a or α-2b pegylated interferon plus ribavirin therapy in liver transplant recipients with different immunosuppression regimes

BACKGROUND

Predictors of sustained virological response (SVR) to antiviral therapy post-liver transplantation (LT) for chronic hepatitis C are needed. In non-transplanted patients, viral kinetics can predict SVR.

OBJECTIVES

To determine the early viral kinetics in LT recipients with different immunosuppression (tacrolimus - Tac- vs. cyclosporine - CsA-) during treatment with peg-IFN+RBV.

STUDY DESIGN

Prospective pilot study in HCV-1b infected patients: (LT CsA n=8; Tac n=8; non-LT n=4), treated with IFN α-2a vs. α-2b (180 μg or 1.5 μg/kg, respectively) once weekly plus weight-based RBV. Median CsA or Tac baseline trough levels were 141 and 7.70 ng/mL, respectively. HCV-RNA was quantified before treatment and after 3, 6, 12h; days 1-6; and weeks 4, 12, 24, 48 and 78 (follow-up).

RESULTS

Different kinetics were observed: early viral load declines with shoulder phase (n=12), delayed monophasic without first phase (n=5, all CsA), and biphasic (n=1) or flat (n=1), without influence of IL28B rs12979860 donor/recipient alleles. In LT, median declines (log(10)UI/mL) at week 4 were -3.62 and -1.49 for Tac vs. CsA; and -2.10 vs.-1.50 for IFN α-2a vs. α-2b (NS), with a trend for faster declines in Tac patients. Generalized additive models suggested a cut-off for predicting response in LT patients of 30 days for Tac, but beyond day 40 for CsA.

CONCLUSION

In LT, the viral kinetics during peg-IFN+RBV treatment is delayed. HCV-RNA at 48 h. may not be predictive of response, and CsA-immunosupressed patients with delayed monophasic declines may potentially achieve ETVR and SVR despite unfavourable or absent early viral load declines.

Liver transplantation and hepatitis C

Hepatitis-C-virus- (HCV-) related end-stage cirrhosis is the primary indication for liver transplantation in many countries. Unfortunately, however, HCV is not eliminated by transplantation and graft reinfection is universal, resulting in fibrosis, cirrhosis, and finally graft decompensation. The use of poor quality organs, particularly from older donors, has a highly negative impact on the severity of recurrence and patient/graft survival. Although immunosuppressive regimens have a considerable impact on the outcome, the optimal regimen after liver transplantation for HCV-infected patients remains unclear. Disease progression monitoring with protocol biopsy and new noninvasive methods is essential for predicting patient/graft outcome and starting antiviral treatment with the appropriate timing. Antiviral treatment with pegylated interferon and ribavirin is currently considered the most promising regimen with a sustained viral response rate of around 30% to 35%, although the survival benefit of this regimen remains to be investigated. Living-donor liver transplantation is now widely accepted as an established treatment for HCV cirrhosis and the results are equivalent to those of deceased donor liver transplantation.

Impact of calcineurin inhibitors with or without interferon on hepatitis C virus titers in a chimeric mouse model of hepatitis C virus infection

Cyclosporine A (CSA) has potent effects against hepatitis C virus (HCV) in vitro, but its clinical efficacy after liver transplantation (LT) is uncertain. We evaluated the impact of CSA and tacrolimus (TAC) with or without concomitant interferon (IFN) therapy on serum HCV titers in a chimeric mouse model of HCV infection. Six groups of HCV-infected mice received only the vehicle, IFN, CSA, CSA and IFN, TAC, or TAC and IFN for 4 weeks. The quantitative HCV polymerase chain reaction levels were determined after 1, 2, and 4 weeks of drug administration. There were no significant differences in the HCV titers after 4 weeks of treatment between the non-IFN-treated groups (log HCV titers: 3.5 ± 0.3 for the vehicle group, 4.4 ± 0.6 for the CSA group, and 4.3 ± 0.4 for the TAC group, P = 0.3). Although IFN had a consistent effect of reducing HCV titers across the groups, there was no significant impact of CSA on HCV levels when it was used alone or in combination with IFN at any time point. The 4-week HCV titers were as follows: 3.2 ± 0.3 for the IFN group, 4.7 ± 0.4 for the CSA/IFN group, and 4.0 ± 0.5 for the TAC/IFN group (P = 0.07). The CSA/IFN and TAC/IFN groups did not differ significantly (P = 0.6). Six of the 7 animals in the IFN group (85.7%) had an HCV titer decline ≥ 1 log, whereas in the test groups (CSA/IFN and TAC/IFN), 6 of 9 animals (66.7%) achieved a 1-log decline in the HCV titer (P = 1). Using this animal model, we could find no evidence supporting the routine use of CSA after LT in HCV-infected patients.

Immunosuppression, liver injury and post-transplant HCV recurrence

Hepatitis C virus (HCV) infection is a major cause for liver transplantation worldwide. Still, HCV re-infection of the graft occurs in almost all cases. Most liver transplant recipients experience episodes of graft hepatitis associated with fibrosis progression and graft failure. Clinical management of graft hepatitis can be challenging as in addition to rejection and HCV-induced hepatitis various other factors might be involved including toxic liver injury, steatohepatitis, ischaemic bile duct lesions or infections with other pathogens. Treatment options are often contradictory for different causes of graft hepatitis, and the role of distinct immunosuppressive drugs has been discussed controversially. Corticosteroids increase the infectivity of HCV by altering expression levels of entry factors and other immunosuppressive agents may have diverse effects on HCV replication and fibrosis progression. Interferon alpha-therapy of hepatitis C shows limited efficacy and tolerability in liver transplant recipients and may also cause rejection. In this review we summarize the current knowledge on mechanisms of liver injury in post-transplant hepatitis C, discuss the pros and cons of immunosuppressive agents in this specific setting and describe potential novel approaches to prevent HCV reinfection.

Liver transplantation and hepatitis C

Hepatitis C virus (HCV)-related end-stage cirrhosis with/without hepatocellular carcinoma is the primary indication for liver transplantation in many countries. Unfortunately, HCV is not eliminated by transplantation and graft re-infection is the rule, resulting in HCV-related graft disease. The natural history of recurrent hepatitis is variable; overall, progression to cirrhosis occurs in 20-30% and allograft failure in 10% after 5-10 years from transplantation. The use of poor quality organs, particularly from old donors, has a significant negative impact on disease severity and transplant outcome. In contrast, antiviral therapy, particularly if it results in permanent eradication of the virus, is associated with improved histology, reduced rate of graft decompensation and enhanced outcome. Disease monitoring, through protocol liver biopsies and new non-invasive tools, is essential to select patients at need of antiviral therapy. Peginterferon with ribavirin, used similarly to what is done in the non-transplant setting, is currently the treatment of choice; sustained viral response is achieved in about 35% of cases. Side effects, particularly anemia, are extremely frequent and sometimes severe (rejection, de novo autoimmune hepatitis). Retransplantation (RT) is the last option for the small subset of patients with allograft failure due to HCV recurrence who fulfil minimum criteria based on RT survival models.

m-TOR inhibitors: what role in liver transplantation?

The development of calcineurin inhibitors (CNIs) led to marked improvements in patient and graft survival after liver transplantation (LTx). We have been left, however, with a dependence on immunosuppressive agents with nephrotoxicity, neurotoxicity, adverse impacts on cardiac risk profile, and risk for malignancy. These challenges need to be met against a dominance of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC) as indications for liver transplant. Unmet needs for immunosuppression (IS) in LTx include: (1) Effective drugs that avoid CNIs toxicities. (2) Agents without adverse impact on HCV recurrence. (3) Compounds that minimize risk of HCC recurrence. New immunosuppressives will need to address the above needs while supporting patient and graft survival equivalent to those achievable with CNIs, ideally without important new toxicities. Two new classes of agents are currently in advanced clinical development: belatacept, and the mammalian target of rapamycin inhibitors (m-TORi). This manuscript will review evidence for a role for m-TORi in LTx in a range of clinical scenarios including patients with CNI nephrotoxicity or neurotoxicity, patients at risk of (or with) HCV recurrence, and patients at risk of HCC recurrence.

Hot topic in hepatitis C virus research: the type of immunosuppression does not matter

1. The natural history of recurrent hepatitis C virus (HCV) is highly variable. Old donor age is a factor that has consistently been shown to affect disease progression. 2. Overall, immunosuppression determines the progression of HCV-related disease; however, the type of immunosuppressive agent used for induction or maintenance is not a key factor. 3. Steroid boluses should be avoided; they are associated with increased viremia, fibrosis progression, and reduced survival. 4. Antiviral therapy, particularly if it is successful, is associated with improved outcomes for liver transplant recipients with HCV. 5. There are no convincing data for modifying the type of immunosuppression before antiviral therapy is started.