Conversion to everolimus in maintenance liver transplant patients: a multicenter, retrospective analysis

Basics and Art of Immunosuppression in Liver Transplantation

Liver transplantation is one of the most challenging areas in the medical field. Despite that, it has already been established as a standard treatment option, especially in decompensated cirrhosis and selected cases of hepatocellular carcinoma and acute liver failure. Complications due to graft rejection, including mortality and morbidity, have greatly improved over time due to better immunosuppressive agents and management protocols. Currently, immunosuppression in liver transplant patients makes use of the best possible combinations of effective agents to achieve optimal immunosuppression for long-term graft survival. Induction agents are no longer used routinely, and the aim is to provide minimal immunosuppression in the maintenance phase. Currently available immunosuppressive agents are mainly classified as biological and pharmacological agents. Though the protocols may vary among the centers and over time, the basics of effective use usually remain similar. Most protocols use the combination of multiple agents with different mechanisms of action to reduce the dose and minimize the side effects. Along with the improvement in operative and perioperative techniques, this art of immunosuppression has contributed to the recent progress made in the outcomes of liver transplants. In this review, we will discuss the various types of immunosuppressive agents currently in use, the different protocols of immunosuppression used, and the art of optimal use for achieving maximum immunosuppression without increasing toxicity. We will also discuss the practical aspects of various immunosuppression regimens, including drug monitoring, and briefly discuss the concepts of immunosuppression minimization and withdrawal.

Therapeutic drug monitoring in kidney and liver transplantation: current advances and future directions

INTRODUCTION

Immunosuppressive drugs (ISD) present a narrow therapeutic window and extremely high inter- and intra-individual pharmacokinetic variability, which complicates their use in solid organ transplant recipients. In order to find a narrow appropriate equilibrium for each patient with the aim of maintaining clinical efficacy and reducing the risk of adverse drug reactions, a complex both clinical and biological monitoring is required, in particular through the use of therapeutic drug monitoring (TDM).

AREA COVERED

This review provides an overview of the available information on the relationship between exposure to immunosuppressive drugs and their efficacy and/or toxicity in kidney and liver transplantation. The aim of the review is to describe the pharmacodynamic/pharmacokinetic relationship that exists for immunosuppressive drugs, to summarize the studies that assess the value of TDM for these drugs in clinical practice, and to present the target and monitoring strategies aimed at optimizing patient immunosuppression, which could help to take a step forward in the field of solid organ transplant patient care.

EXPERT OPINION

To improve the care of transplant patients, several TDM innovations can be pursued by investigators. Among these, the development of microsampling methods for TDM or the combination of pharmacodynamic biomarkers with ISD exposure measurements appear to be relevant strategies.

Metabolic Disorders in Liver Transplant Recipients: The State of the Art

Liver transplantation represents a chief therapeutic approach for acute liver failure, end-stage liver disease and hepatocellular carcinoma. Despite witnessing advancements in short- and medium-term survival over recent decades, attributed to refinements in surgical techniques and immunosuppressive protocols, long-term mortality remains impervious to modification. Notably, cardiovascular disease emerges as a predominant cause of mortality among liver transplant recipients. This trend is accentuated by the increasing prominence of non-alcoholic steatohepatitis-related cirrhosis as an indication for liver transplantation. Moreover, the administration of immunosuppressive agents is intricately linked to the degradation of the metabolic profile in liver transplant recipients, thereby contributing to the initiation or exacerbation of cardiovascular risk factors, such as hypertension, diabetes, and dyslipidaemia. In addition, the post-liver transplantation period is marked by a decline in lifestyle quality and a failure to acknowledge the psychological distress experienced by patients throughout the transplant process. These factors can precipitate a deterioration in the patient's metabolic profile, exacerbated by suboptimal therapeutic compliance. This narrative review aims to comprehensively address the principal metabolic disorders intricately associated with liver transplantation.

Determination of five mTOR inhibitors in human plasma for hepatocellular carcinoma treatment using QuEChERS-UHPLC-MS/MS

A fast and reliable QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) method for pre-processing combined with Ultra - high performance liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS) was established for the analysis of five mammalian rapamycin target protein (mTOR) inhibitors (vistusertib, AZD8055, pictilisib, everolimus, temsirolimus)in human plasma. Extraction was achieved by addition of acetonitrile to the sample followed by anhydrous magnesium sulfate and 30 mg C18 for salting out and purification, respectively. MTOR inhibitors were detected using selective response monitoring (SRM) under positive ion electrospray mode. Vistusertib, AZD8055 and pictilisib showed good linearity with a range of 1-80 ng/ml, Additionally, the concentration of everolimus and temsirolimus was 2.5-200 ng/ml and10-800 ng/ml, respectively. The linear correlation coefficient (R2) of each analysis was ≥ 0.9950. The limit of detection (LOD) and Limit of Quantitation (LOQ) were 0.015-0.75 ng/ml and 1-10 ng/ml, respectively. This method showed a high accuracy with high recovery rate and excellent stability. This method is fast, accurate and reliable, suitable for quantitative detection of mTOR inhibitors in human plasma.

Evolving challenges with long-term care of liver transplant recipients

The number of liver transplants (LT) performed worldwide continues to rise, and LT recipients are living longer post-transplant. This has led to an increasing number of LT recipients requiring lifelong care. Optimal care post-LT requires careful attention to both the allograft and systemic issues that are more common after organ transplantation. Common causes of allograft dysfunction include rejection, biliary complications, and primary disease recurrence. While immunosuppression prevents rejection and reduces incidences of some primary disease recurrence, it has detrimental systemic effects. Most commonly, these include increased incidences of metabolic syndrome, various malignancies, and infections. Therefore, it is of utmost importance to optimize immunosuppression regimens to prevent allograft dysfunction while also decreasing the risk of systemic complications. Institutional protocols to screen for systemic disease and heightened clinical suspicion also play an important role in providing optimal long-term post-LT care. In this review, we discuss these common complications of LT as well as unique considerations when caring for LT recipients in the years after transplant.

Antineoplastic chemotherapy and immunosuppression in liver transplant recipients: Squaring the circle?

BACKGROUND

Malignancies are a major cause of late death after liver transplantation (LT). In LT recipients presenting a malignancy, antineoplastic chemotherapy is central part of the therapeutic arsenal, but management of both immunosuppressive and antineoplastic chemotherapy can be very challenging. The aim of the present retrospective study was to describe a recent single center cohort of LT recipients treated with antineoplastic cytotoxic chemotherapy.

METHODS

All LT recipients who received antineoplastic chemotherapy in our center between 2005 and 2021 were included.

RESULTS

The study population included 72 antineoplastic chemotherapy courses in 69 patients. There was a majority of men (81.9%); median age at LT was 54.9 (range 1-68) and was 63.0 (18-79) at the diagnosis of malignancy. Lung carcinomas (23.6%), head and neck carcinomas (20.8%), lymphomas (16.7%), and recurrent hepatocellular carcinoma (HCC) (8.3%) were the most frequent malignancies. Neoadjuvant (30.6%), adjuvant (12.5%) or palliative (54.2%) chemotherapy was performed. Immunosuppressive regimen was modified from a calcineurin inhibitor (CNI)-based to an everolimus-based regimen (63.5% of CNI discontinuation). Median survival after diagnosis of malignancy was 22.5 months and 5-year survival was 30.1%. Chemotherapy regimen was considered optimal in 81.9% of the cases. Multivariate analysis disclosed that non-PTLD N+ stage malignancy (HR = 5.52 95%CI [1.40;21.69], p = .014), non-PTLD M+ stage malignancy (HR = 10.55 95%CI [3.20;34.73], p = .0001), and suboptimal chemotherapy (HR = 2.73 95%CI [1.34;5.56], p = .005) were significantly associated with poorer prognosis. No rejection episode occurred during chemotherapy.

CONCLUSIONS

The present study is the first one focused on antineoplastic chemotherapy in LT recipients. Our results suggest that immunosuppressive drugs and antineoplastic chemotherapy can be managed satisfactorily in most cases but this needs confirmation from larger cohorts.

Risks and ways of preventing kidney dysfunction in drug-induced immunosuppression in solid organ recipients

Immunosuppressive therapy (IMT) is the cornerstone of treatment after transplantation. The goal of immunosuppression is to prevent acute and chronic rejection while maximizing patient survival and long-term graft function. However, the expected effects of IMT must be balanced against the major adverse effects of these drugs and their toxicity. The purpose of this review is to summarize world experience on current immunosuppressive strategies and to assess their effects on renal function.

Current aspects of renal dysfunction after liver transplantation

The development of chronic kidney disease (CKD) after liver transplantation (LT) exerts a severe effect on the survival of patients. The widespread adoption of the model for end-stage liver disease score strongly impacted CKD incidence after the procedure, as several patients are transplanted with previously deteriorated renal function. Due to its multifactorial nature, encompassing pre-transplantation conditions, perioperative events, and nephrotoxic immunosuppressor therapies, the accurate identification of patients under risk of renal disease, and the implementation of preventive approaches, are extremely important. Methods for the evaluation of renal function in this setting range from formulas that estimate the glomerular filtration rate, to non-invasive markers, although no option has yet proved efficient in early detection of kidney injury. Considering the nephrotoxicity of calcineurin inhibitors (CNI) as a factor of utmost importance after LT, early nephroprotective strategies are highly recommended. They are based mainly on delaying the application of CNI during the immediate postoperative-period, reducing their dosage, and associating them with other less nephrotoxic drugs, such as mycophenolate mofetil and everolimus. This review provides a critical assessment of the causes of renal dysfunction after LT, the methods of its evaluation, and the interventions aimed at preserving renal function early and belatedly after LT.

Immunosuppressive Drugs

Immunosuppressant is a class of medicines that inhibit or decrease the intensity of the immune response in the body. Most of these medications are used to allow the body less likely to resist a transplanted organ. In solid organ transplantation, immunosuppressive agents are needed for the activation of early-stage immunosuppression, the management of late-stage immunosuppression or for the maintenance of organ rejection. The emergence of novel agents and improvements in immunosuppression regimens after transplantation are significant factors leading to this progress. However, these drugs also increase the risk of infection, cancers and specific adverse side effects specific to each agent in patients particularly in pregnant women and fertility issues. Corona virus disease being hot topic of debate is has given positive outcome to immunosuppressive drugs however need more attention in future. Transplant centers across the world utilize multiple immunosuppression protocols; nevertheless, each patient can require an individually formulated immunosuppression regimen to manage the advantages and possible damage of treatment thus eliminating the likelihood of their primary disease recurrence.

Real-Life Experience of mTOR Inhibitors in Liver Transplant Recipients in a Region Where Living Donation Is Predominant

Background: Mammalian target of rapamycin (mTOR) inhibitors, such as everolimus and sirolimus, may be efficacious in preserving renal function in liver transplantation (LT) recipients while preventing hepatocellular carcinoma (HCC) recurrence.

Materials and Methods: In this study, we retrospectively evaluated the safety, efficacy, and renoprotective effects of mTOR inhibitors in LT recipients. Among the 84 patients enrolled, mTOR inhibitor was commenced during the first year after LT. Renal function was measured by estimated glomerular filtration rate (eGFR) using the Modification of Diet in Renal Disease equation.

Results: Regarding the type of mTOR inhibitor, everolimus was used in 71 patients and sirolimus in 13 patients. Concomitant tacrolimus was used in 63 patients (75.0%). For total enrolled patients, kidney function did not significantly change during 12 months after initiation of mTOR inhibitors, although tacrolimus-withdrawn patients (n = 21) showed better kidney function compared to tacrolimus-minimized patients (n = 63) after conversion. However, a significant improvement in kidney function was observed in the eGFR <60 ml/min/1.73 m2 group (n = 19) 12 months after initiation of mTOR inhibitors, for both patient groups with early + mid starters (n = 7, stating within 1 year after LT) and late starters (n = 12, starting over 1 year after LT). mTOR inhibitors were safely administered without serious adverse events that led to drug discontinuation.

Conclusion: We demonstrated that patients with renal impairment showed significant improvement in renal function regardless of the timing of mTOR inhibitor start, suggesting that switch to mTOR inhibitors may be beneficial when renal function declines.

Early use of everolimus improved renal function after adult deceased donor liver transplantation

Background

Methods

Results

Conclusions

Immunosuppressive regimens for adult liver transplant recipients in real-life practice: consensus recommendations from an Italian Working Group

It is a well-recognized fact that implementing new guidelines in clinical practice may be difficult; therefore the Italian Society for Organ and Tissue Transplantation (SITO) set out to define practical immunosuppression tools for the management of liver transplantation patients. In 2017, an Italian Working Group of liver transplant experts and hepatologists issued a set of consensus statements along with evidence-based recommendations on the use of everolimus after liver transplantation. This article presents the evidence- and consensus-based algorithms developed within the Italian Working Group, which are aimed towards guiding clinicians in the selection of immunosuppressive regimens for the management of adult liver transplant recipients in real-life practice. The liver transplant recipient population, typically managed in clinical practice, was divided into the following categories: (1) standard patients; (2) critically ill patients; (3) patients with a specific etiology; (4) patients with hepatocellular carcinoma; (5) and patients with de novo malignancies. The algorithms are divided into two parts, according to the time from transplantation (0-3 months and > 3 months) and are discussed here along with relevant supporting literature, when available. Ultimately, it is hoped that the evidence- and consensus-based algorithms developed within the Italian Working Group, and presented here, contribute to simplify, personalize, and optimize immunosuppression of liver transplantation recipients in clinical practice.

Renal disease in the allograft recipient

Chronic renal failure after liver transplantation (LT) is significantly more frequent than after lung or heart transplantation and it results in an increased short and long-term mortality. Renal impairment may occur before LT (functional or due to preexisting parenchymal kidney disease), in the peri-operative period or later after LT. The number of patients with renal failure after LT has increased due to the liver allocation based on MELD and to the more liberal use of higher risk grafts. Calcineurin inhibitor (CNI) nephrotoxicity is the most important cause of renal dysfunction but is a modifiable factor. Strategy to prevent CNI-associated nephrotoxicity is post-op CNI minimization by induction therapy and reduced dose and/or delayed introduction of CNI in combination with mycophenolate mofetil (MMF) or everolimus with no penalty in term of rejection. With everolimus, usually started one month after LT, a drastic minimization of CNI is possible and this results in superior kidney function until at least 3 years follow up. At the moment of renal impairment a drastic reduction of CNI dose together with the introduction of MMF results in an improvement in GFR at 6 to 2 years with a low rate of acute rejection. However, secondary prevention fails to normalize renal function in most of the patients once e GFR <60 ml/min/1.73m²ml.

Immunosuppression in liver transplant

The increasing potency of immunosuppression (IS) agents resulted in significantly decreased rates of steroid resistant rejection and rejection related graft loss in liver transplantation (LT). Currently, more than two thirds of late mortality after LT is unrelated to graft function. However, the increased benefit of more potent IS drugs, coupled with the prolonged survival of transplant recipients led to longer patients exposure to these drugs and their unwanted adverse effects, creating a double-edged sword. In this article the authors describe the mechanism of action and the adverse effects of the most commonly used immunosuppressed drugs, and the most commonly used IS regimens for both induction and maintenance regimens. The balance between the ideal IS regimen to prevent rejection and the need to minimize the dose of IS drugs in order to prevent the adverse effects related to its use requires the knowledge of the science and the experience with the art of medicine. The different protocols aimed at protecting renal function and preventing the development of de novo cancer and metabolic syndrome are discussed here. The main causes of mortality late after liver transplant are associated with prolonged use of IS medications, and clear evidence exists about over-immunosuppression of recipients of liver transplant. The current status of strategies of IS minimization and withdrawal are reviewed in this article, with evaluation of its benefits and pitfalls.

Risk factors of tuberculosis after liver transplant in a tertiary care hospital

BACKGROUND

Tuberculosis (TB) is a serious opportunistic infection in liver transplant (LT) recipients with a high rate of morbidity and mortality. This study aims to clarify the frequency and risk factors for tuberculosis in LT recipients.

METHODS

A total of 884 LT recipients were investigated retrospectively at China Medical University Hospital, Taichung, Taiwan. We performed a case-control study (1:2) to investigate the potential risk factors and disease onset of TB after LT.

RESULTS

Among the 884 LT recipients, 25 of TB cases (2.8%) were reported from 2009 to 2016. The overall incidence of TB was 744 cases per 100,000 patient-year, which was 18-fold higher than the general population in Taiwan. The median time to develop TB after liver transplant was 20 months. Of the TB cases, 15 were pulmonary TB and 10 were extra-pulmonary TB. Five cases of those extra-pulmonary TB occurred in the first post-transplant year. Overall five-year survival rate was 63.3%. Multivariate analyses identified apical fibrotic change in pre-transplant computed tomographic (CT) finding and the exposure to mammalian target of rapamycin (mTOR) inhibitors before TB event as independent risk factors for TB development (Odd ratio (OR) 10.79, 95% confidence interval (CI), 1.73-67.49, p = 0.01; OR 3.847, 95% CI 0.80-18.51, P = 0.09, respectively).

CONCLUSION

TB incidence in LT recipients is high in this study. Among those post-transplant recipients with long-term immunosuppression, abnormal CT finding and exposure to mTOR inhibitors before liver transplant might be the risk factors for TB.

mTOR inhibitors in pediatric liver transplant recipients

BACKGROUND

During the past decade, mTOR inhibitors (mTORi), everolimus and sirolimus, have been increasingly used after adult liver transplantation (LT). The aim of the present study was to describe the use of mTORi in pediatric LT recipients.

METHODS

All pediatric LT recipients who received mTORi before December 2017 from 4 European pediatric LT centers were included and analyzed.

RESULTS

The present retrospective study included 30 patients; 21 were male (70%), median age was 9.3 years (range: 1.2-17.1 years) at mTORi introduction. Main indications for mTORi introduction were pre-existing liver malignancy (43.3%), calcineurin inhibitor (CNI) nephrotoxicity (26.7%), or rejection (23.4%). At last follow-up, mTORi CNIs were withdrawn in 10 patients (10/29, 34.5%). The median dose of mTORi was 1.8 mg/day (range: 0.3-5.0) or 0.058 mg/kg/day (range: 0.01-0.26), and the median trough level was 5.1 μg/L (range: 1.0-15.5). After a median follow-up of 2.8 years (range: 0.2-10.0), 50.0% of the patients presented with at least one adverse event. The main adverse events included hyperlipidemia, proteinuria, dermatitis, and mucitis. Overall mTORi discontinuation rate was 23.3% (10.0% because of adverse event). Introduction of mTORi had no significant impact on renal function.

CONCLUSION

Our results suggest that mTORi can be used in pediatric LT recipients in different clinical situations, both to reinforce immunosuppressive therapy, and to reduce CNI and related toxicity.

Cardiovascular Disease Outcomes Related to Early Stage Renal Impairment After Liver Transplantation

BACKGROUND

In the general population, even mild renal disease is associated with increased cardiovascular (CV) complications. Whether this is true in liver transplant recipients (LTR) is unknown.

METHODS

This was a retrospective cohort study of 671 LTR (2002-2012) from a large urban tertiary care center and 37 322 LTR using Vizient hospitalization data linked to the United Network for Organ Sharing. The 4-variable Modification of Diet in Renal Disease equation estimated glomerular filtration rate (eGFR). Outcomes were 1-year CV complications (death/hospitalization from myocardial infarction, heart failure, atrial fibrillation, cardiac arrest, pulmonary embolism, or stroke) and mortality. Latent mixture modeling identified trajectories in eGFR in the first liver transplantation (LT) year in the 671 patients.

RESULTS

Mean (SD) eGFR was 72.1 (45.7) mL/min per 1.73 m. Six distinct eGFR trajectories were identified in the local cohort (n = 671): qualitatively normal-slow decrease (4% of cohort), normal-rapid decrease (4%), mild-stable (18%), mild-slow decrease (35%), moderate-stable (30%), and severe-stable (9%). In multivariable analyses adjusted for confounders and baseline eGFR, the greatest odds of 1-year CV complications were in the normal-rapid decrease group (odds ratio, 10.6; 95% confidence interval, 3.0-36.9). Among the national cohort, each 5-unit lower eGFR at LT was associated with a 2% and 5% higher hazard of all-cause and CV-mortality, respectively (P < 0.0001), independent of multiple confounders.

CONCLUSIONS

Even mild renal disease at the time of LT is a risk factor for posttransplant all-cause and CV mortality. More rapid declines in eGFR soon after LT correlate with risk of adverse CV outcomes, highlighting the need to study whether early renal preservation interventions also reduce CV complications.

Very Early Introduction of Everolimus in De Novo Liver Transplantation: Results of a Multicenter, Prospective, Randomized Trial

Early everolimus (EVR) introduction and tacrolimus (TAC) minimization after liver transplantation may represent a novel immunosuppressant approach. This phase 2, multicenter, randomized, open-label trial evaluated the safety and efficacy of early EVR initiation. Patients treated with corticosteroids, TAC, and basiliximab were randomized (2:1) to receive EVR (1.5 mg twice daily) on day 8 and to gradually minimize or withdraw TAC when EVR was stable at >5 ng/mL or to continue TAC at 6-12 ng/mL. The primary endpoint was the proportion of treated biopsy-proven acute rejection (tBPAR)-free patients at 3 months after transplant. As secondary endpoints, composite tBPAR plus graft/patient loss rate, renal function, TAC discontinuation rate, and adverse events were assessed. A total of 93 patients were treated with EVR, and 47 were controls. After 3 months from transplantation, 87.1% of patients with EVR and 95.7% of controls were tBPAR-free (P = 0.09); composite endpoint-free patients with EVR were 85% (versus 94%; P = 0.15). Also at 3 months, 37.6% patients were in monotherapy with EVR, and the tBPAR rate was 11.4%. Estimated glomerular filtration rate was significantly higher with EVR, as early as 2 weeks after randomization. In the study group, higher rates of dyslipidemia (15% versus 6.4%), wound complication (18.32% versus 0%), and incisional hernia (25.8% versus 6.4%) were observed, whereas neurological disorders were more frequent in the control group (13.9% versus 31.9%; P < 0.05). In conclusion, an early EVR introduction and TAC minimization may represent a suitable approach when immediate preservation of renal function is crucial.

International Liver Transplantation Society Consensus Statement on Immunosuppression in Liver Transplant Recipients

Effective immunosupression management is central to achieving optimal outcomes in liver transplant recipients. Current immunosuppression regimens and agents are highly effective in minimizing graft loss due to acute and chronic rejection but can also produce a substantial array of toxicities. The utilization of immunosuppression varies widely, contributing to the wide disparities in posttransplant outcomes reported between transplant centers. The International Liver Transplantation Society (ILTS) convened a consensus conference, comprised of a global panel of expert hepatologists, transplant surgeons, nephrologists, and pharmacologists to review the literature and experience pertaining to immunosuppression management to develop guidelines on key aspects of immunosuppression. The consensus findings and recommendations of the ILTS Consensus guidelines on immunosuppression in liver transplant recipients are presented in this article.

Cross-sectional analysis of immunosuppressive regimens focused on everolimus after liver transplantation in a Korean high-volume transplantation center

Background

The mammalian target of the rapamycin inhibitor has dual inhibitory effects on cell growth and angiogenesis. This study aimed to analyze the usage of everolimus on actual immunosuppression (IS) regimens through a cross-sectional study in a high-volume liver transplantation (LT) center.

Methods

Our institutional LT database was searched for adult patients who underwent primary LT surgery between January 2010 and December 2016. We identified 2,093 LT recipients with observation periods of 1 to 8 years.

Results

We divided the 2,093 recipients into three groups according to the posttransplant follow-up period as follows: group A (12–36 months; n=680), group B (37–60 months; n=560), and group C (>60 months; n=853). The individual IS agents were tacrolimus in 1,807 patients (86.3%), cyclosporine in 169 patients (8.1%), mycophenolate mofetil (MMF) in 1,310 patients (62.6%), and everolimus in 115 patients (5.5%). The most common IS regimens were tacrolimus-MMF combination and tacrolimus monotherapy, regardless of the posttransplant period. Patients with pretransplant malignancies were administered everolimus more frequently than those without pretransplant malignancies (P<0.001). In 102 patients with hepatocellular carcinoma recurrence or de novo malignancies, IS regimens included everolimus-tacrolimus in 41 patients (40.2%), tacrolimus-MMF in 27 patients (26.4%), tacrolimus in 20 patients (19.6%), MMF in 10 patients (9.8%), cyclosporine in three patients (2.9%), and cyclosporine-MMF in one patient (1.0%).

Conclusions

Administration of everolimus after LT has been gradually increasing with the expansion of indications in our institutional practice. Currently, the role of everolimus is minimal and not comparable to that of tacrolimus, but it has a unique position in the field of IS after LT.

Assessing the role of everolimus in reducing hepatocellular carcinoma recurrence after living donor liver transplantation for patients within the UCSF criteria: re-inventing the role of mammalian target of rapamycin inhibitors

Backgrounds/Aims

The protective effect of everolimus (EVR) in hepatocellular carcinoma (HCC) patients who receive liver transplantation in terms of reducing the recurrence has not been sufficiently investigated in clinical trials. In this second stage of our ongoing study, we intend to analyze the effects of EVR as an immunosuppressant, when it is started in the early phase after living donor liver transplantation (LDLT), on HCC recurrence in patients with HCC within the University of California at San Francisco (UCSF) criteria.

Methods

From January 2011 to June 2013, a total of 250 patients underwent LDLT for HCC at our institute. The patients with HCC within the UCSF criteria were included in the study and divided in two groups depending upon the postoperative immunosuppression. Group A: HCC patients that received EVR+TAC based immunosuppressive regimen (n=37). Group B: HCC patients that received standard TAC based immunosuppressive regimen without EVR (n=29). The target trough level for EVR was 3 to 5 ng/ml while for TAC it was 8–10 ng/ml.

Results

For group A patients, the mean trough level of the EVR was 3.47±1.53 ng/ml (range, 1.5–11.2) with a daily dose of 1.00±0.25 mg/day. For group A and B, the average TAC trough levels were 6.97±3.98 ng/ml (range, 2.50 to 11.28 ng/ml) and 6.93±2.58 (range, 2–16.30), respectively. The 1-year, 3-year and 4-year overall survival achieved for Group A patients was 94.95%, 86.48% and 86.48%, respectively while for Group B patients it was 82.75%, 68.96%, and 62.06%, respectively (p=0.0217).

Conclusions

EVR use in liver transplant recipients in the early stage after transplantation reduces the HCC recurrence rates in HCC patients within the UCSF criteria.

Use of everolimus in liver transplantation

In recent years, the use of mammalian target of rapamycin inhibitors has gained traction in their use as alternative or adjunct immunosuppressants in the post-liver transplantation (LT) setting. The efficacy of everolimus (EVR) in de novo LT is established and a reasonable time to initiate EVR is 30 d from LT surgery. Initiating EVR early post-LT allows for calcineurin inhibitor (CNI) reduction, thus reducing nephrotoxicity in LT recipients. However, data is inadequate on the appropriate timing for conversion from CNI to EVR maintenance in order to achieve optimal renoprotective effect without compromising drug efficacy. Adverse effects of proteinuria, hypercholesterolemia and hyperlipidemia are significantly higher as compared to standard CNI and long-term implications on graft and patient survival in LT is still unclear. Future research to explore strategies to minimise EVR adverse effects will be crucial for the success of EVR as an important alternative or adjunct immunosuppressive therapy in LT.

Recommendations of everolimus use in liver transplant

Mammalian target of rapamycin (mTOR) inhibitors, everolimus (EVL) and sirolimus are immunosuppressive agents with a minor nephrotoxic effect, limited to the development of proteinuria in some cases. The combination of EVL and low-dose tacrolimus has proven to be as safe and effective as standard therapy with tacrolimus for the prevention of acute cellular rejection. Early initiation of EVL-based immunosuppressive regimens with reduced exposure to calcineurin inhibitors has been shown to significantly improve renal function of LT recipients during induction and maintenance phases, with comparable efficacy and safety profiles. In patients with established kidney failure, initiating EVL may enable clinicians to reduce calcineurin inhibitors exposure, thereby contributing to the improved renal function of these patients. Although there is not sufficient evidence to recommend their use to prevent the recurrence of hepatocellular carcinoma and the progression of de novo tumours, they are used in this context in routine clinical practice.

Immunosuppression strategies in liver transplantation patient; patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) consists the main primary malignant tumor of the liver. There is an underlining liver cirrhosis mainly attributed to chronic hepatitis B virus or hepatitis C virus, alcoholic liver disease, nonalcoholic steatohepatitis and other pathologic conditions. Liver transplantation consists a radical management, treating both cancer and cirrhosis. By introducing the Milan Criteria for liver transplantation in HCC patients there was a 5-year survival escalation. Even though there is a careful selection of patients with HCC for transplantation, recurrent disease is still high. The role of immusuppression therapy is of paramount importance, in order to avoid acute and chronic graft rejection while protecting the patient from tumor recurrence. In recent years newer immunosuppressive agents such as the mTOR inhibitors are proposed, having dual properties, as both immunosuppressive and antitumors agents.

Use of Everolimus in Liver Transplantation: Recommendations From a Working Group

Immunosuppression after liver transplantation (LT) is presently based on use of calcineurin inhibitors (CNI), although they are associated with an increased incidence of renal dysfunction, cardiovascular complications, and de novo and recurrent malignancies. Over the past decade, mammalian target of rapamycin inhibitors have received considerable attention as immunosuppressants because they are associated with a more favorable renal profile versus CNI, as well as antiproliferative activity in clinical studies. Comprehensive guidelines on use of everolimus (EVR) in LT are still lacking. In Italy, a project, named Everolimus: the road to long-term functioning, was initiated to collect the experience on EVR after LT with the aim of providing guidance for transplant clinicians. Herein, recommendations by this national consensus group, based on Delphi methodology, are presented. Consensus was reached on 20 of the 23 statements proposed, and their level of evidence, grade of recommendation, and percent of agreement are reported. Statements are grouped into 4 areas: (A) renal function; (B) time of EVR introduction, CNI reduction and elimination, and risk for graft rejection; (C) antiproliferative effects of EVR; and (D) management of EVR-related adverse events. The high level of consensus shows that there is good agreement on the routine use of EVR in predefined clinical scenarios, especially in light of posttransplant nephrotoxicity and other adverse events associated with long-term administration of CNIs.

The authors summarize the recommendations reached by an Italian National Consensus group using the Delphi methodology on the use of everolimus in liver transplantation, particularly its role in renal function, antiproliferative effects, adverse events, timing of introduction, and rejection risk.

Modification of immunosuppressive therapy as risk factor for complications after liver transplantation

Management of complications post-liver transplantation (LT) includes immunosuppressive manipulations with the aim to reduce the overall burden of immunologic suppression and compensate for renal, cardiovascular, metabolic toxicities, and for the increased oncologic risk. Two approaches can be implemented to reduce immunosuppression-related adverse events: upfront schedules tailored to the pretransplant individual patient's risk profile versus downstream modifications in the event of immunosuppression-related complications. Upfront strategies are supported by evidence originating from prospective randomized trials and consist of triple/quadruple schedules whereby calcineurin inhibitors (CNI)-exposure is reduced with combination of anti-CD25 monoclonal antibodies, antimetabolites and corticosteroids. Quadruple regimens allow for staggering of CNI introduction and higher renal function in the early term, but their superiority in the long term has not yet been established. A more recent upfront schedule contemplates early (4 weeks) introduction of mammalian target of rapamycin inhibitor (mTORi) everolimus and allows for reduction of CNI up to 4 years posttransplantation. Incorporation of mTORi has the potential to prolong time to recurrence for patients with hepatocellular carcinoma. However, as suggested by the available evidence, downstream immunosuppressive manipulations are more frequently adopted in clinical practice. These encompass CNI replacement and immunosuppression withdrawal. Switching CNI to mTORi monotherapy is the option most commonly adopted to relieve renal function and compensate for posttransplant malignancies. Its impact is dependent on interval from transplantation and underlying severity of renal impairment. Introduction of mTORi is associated with longer overall survival for patients with extrahepatic posttransplant malignancies, but results are awaited for recurrences of hepatocellular carcinoma. Immunosuppression withdrawal seems feasible (70%) in very long term survivors (>10 years), but is not associated with reversal of immunosuppression-related complications. Awaiting novel immunosuppressive drug categories, integration of upfront strategies with the aim to reduce CNI-exposure and a low threshold for adjustment in the posttransplant course are both advisable to improve long-term outcomes of LT.

Therapeutic Drug Monitoring of Everolimus: A Consensus Report

In 2014, the Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology called a meeting of international experts to provide recommendations to guide therapeutic drug monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice. EVR is a potent inhibitor of the mammalian target of rapamycin, approved for the prevention of organ transplant rejection and for the treatment of various types of cancer and tuberous sclerosis complex. EVR fulfills the prerequisites for TDM, having a narrow therapeutic range, high interindividual pharmacokinetic variability, and established drug exposure-response relationships. EVR trough concentrations (C0) demonstrate a good relationship with overall exposure, providing a simple and reliable index for TDM. Whole-blood samples should be used for measurement of EVR C0, and sampling times should be standardized to occur within 1 hour before the next dose, which should be taken at the same time everyday and preferably without food. In transplantation settings, EVR should be generally targeted to a C0 of 3-8 ng/mL when used in combination with other immunosuppressive drugs (calcineurin inhibitors and glucocorticoids); in calcineurin inhibitor-free regimens, the EVR target C0 range should be 6-10 ng/mL. Further studies are required to determine the clinical utility of TDM in nontransplantation settings. The choice of analytical method and differences between methods should be carefully considered when determining EVR concentrations, and when comparing and interpreting clinical trial outcomes. At present, a fully validated liquid chromatography tandem mass spectrometry assay is the preferred method for determination of EVR C0, with a lower limit of quantification close to 1 ng/mL. Use of certified commercially available whole-blood calibrators to avoid calibration bias and participation in external proficiency-testing programs to allow continuous cross-validation and proof of analytical quality are highly recommended. Development of alternative assays to facilitate on-site measurement of EVR C0 is encouraged.

Protecting the Kidney in Liver Transplant Recipients: Practice-Based Recommendations From the American Society of Transplantation Liver and Intestine Community of Practice

Both acute and chronic kidney disease are common after liver transplantation and result in significant morbidity and mortality. The introduction of the Model for End-stage Liver Disease score has directly correlated with an increased prevalence of perioperative renal dysfunction and the number of simultaneous liver-kidney transplantations performed. Kidney dysfunction in this population is typically multifactorial and related to preexisting conditions, pretransplantation renal injury, perioperative events, and posttransplantation nephrotoxic immunosuppressive therapies. The management of kidney disease after liver transplantation is challenging, as by the time the serum creatinine level is significantly elevated, few interventions affect the course of progression. Also, immunological factors such as antibody-mediated kidney rejection have become of greater interest given the rising liver-kidney transplant population. Therefore, this review, assembled by experts in the field and endorsed by the American Society of Transplantation Liver and Intestine Community of Practice, provides a critical assessment of measures of renal function and interventions aimed at preserving renal function early and late after liver and simultaneous liver-kidney transplantation. Key points and practice-based recommendations for the prevention and management of kidney injury in this population are provided to offer guidance for clinicians and identify gaps in knowledge for future investigations.

Immunoregulatory Effects of Everolimus on In Vitro Alloimmune Responses

Everolimus (EVL) is a novel mTOR-inhibitor similar to sirolimus (SRL) that is used in organ transplant recipients, often in combination with tacrolimus (TAC) or mycophenolate (MPA). The current study aims to determine its effects on regulatory T cells. Increasing concentrations of EVL, MPA and TAC alone or in combination were added to MLRs of healthy volunteers. Lymphoproliferation by 3H-TdR incorporation and the percentage of newly generated CD4+CD127-CD25+FOXP3+ (total Treg) and CD4+CD127-CD25HighFOXP3+ (natural Treg) in CFSE labeled responder cells were assessed by flow cytometry. In comparison to medium controls, EVL and other agents dose-dependently inhibited 3H-TdR incorporation in HLA-2DR-matched and HLA-mismatched MLRs (n = 3-10). However, EVL significantly amplified newly generated total and natural Tregs in CFSE labeled responder cells (p<0.05) at all concentrations, while MPA and SRL did this only at sub-therapeutic concentrations and inhibited at therapeutic levels. In contrast, TAC inhibited newly generated Tregs at all concentrations. When tested in combination with TAC, EVL failed to reverse TAC inhibition of Treg generation. Combinations of EVL and low concentrations of MPA inhibited proliferation and amplified Treg generation in an additive manner when compared to medium controls or each drug tested alone (p<0.05). The relative tolerogenic effect from high to low was EVL > SRL> MPA > TAC. If the results from these in vitro studies are extrapolated to clinical transplantation, it would suggest EVL plus low concentrations of MPA may be the most tolerogenic combination.

Optimization of immunosuppressive medication upon liver transplantation against HCC recurrence

The introduction of liver transplant listing criteria for hepatocellular cancer (HCC) has significantly improved oncological outcomes and survival. But despite this HCC recurrence is still problematic. There is emerging evidence that the choice of immunosuppression (IS) after transplant for HCC can influence oncological survival and HCC recurrence. The following is a short summary of what has been published on HCC recurrence with the different classes of immunosuppressive agents in present use, concluding with the possible rationalization of the use of these immunosuppressive agents in the post-transplant patient at high risk of recurrence.

Lipids in liver transplant recipients

Hyperlipidemia is very common after liver transplantation and can be observed in up to 71% of patients. The etiology of lipid disorders in these patients is multifactorial, with different lipid profiles observed depending on the immunosuppressive agents administered and the presence of additional risk factors, such as obesity, diabetes mellitus and nutrition. Due to recent improvements in survival of liver transplant recipients, the prevention of cardiovascular events has become more important, especially as approximately 64% of liver transplant recipients present with an increased risk of cardiovascular events. Management of dyslipidemia and of other modifiable cardiovascular risk factors, such as hypertension, diabetes and smoking, has therefore become essential in these patients. Treatment of hyperlipidemia after liver transplantation consists of life style modification, modifying the dose or type of immunosuppressive agents and use of lipid lowering agents. At the start of administration of lipid lowering medications, it is important to monitor drug-drug interactions, especially between lipid lowering agents and immunosuppressive drugs. Furthermore, as combinations of various lipid lowering drugs can lead to severe side effects, such as myopathies and rhabdomyolysis, these combinations should therefore be avoided. To our knowledge, there are no current guidelines targeting the management of lipid metabolism disorders in liver transplant recipients. This paper therefore recommends an approach of managing lipid abnormalities occurring after liver transplantation.

Everolimus plus mycophenolate mofetil as initial immunosuppression in liver transplantation

BACKGROUND

The purpose of this study was to assess the efficacy and safety of a de novo immunosuppressive regimen with everolimus (EVL) plus mycophenolate mofetil (MMF) without calcineurin inhibitors (CNI) for liver transplantation. The secondary purpose was to compare the renal function with a control group of patients treated with tacrolimus plus MMF.

METHODS

Sixteen male and 4 female liver transplant patients received immunosuppression with EVL plus MMF without CNI, with induction with steroids and 16 with basiliximab also. In 10 cases it was indicated as induction immunosuppression without CNI as prevention against nephrotoxicity and neurotoxicity or recurrence of hepatocarcinoma in predisposed patients and in another 10 after withdrawing CNI during the immediate post-transplant period, before hospital discharge, as the result of toxicity, mainly nephrotoxicity and neurotoxicity or the presence of hepatocarcinoma with a high risk of recurrence. A control group comprising 31 patients taking tacrolimus plus MMF was included to compare the renal function.

RESULTS

The mean follow-up time was 24 months. One patient had a recurrence of hepatocarcinoma at 8 months after transplant. The cases of nephrotoxicity and neurotoxicity resolved favorably. There were 7 rejections (35%); 2 evolved to chronic rejection with both needing retransplantation, 2 resolved with dose adjustment, and 3 required conversion to CNI. The side effects were hyperlipidemia (25%), wound dehiscence (10%), lymphedema (10%), cytomegalovirus infection (25%), myelotoxicity (25%) and proteinuria >1 g in 1 case (5%). No differences were found in renal function between the two groups.

CONCLUSIONS

This regimen was proven to be efficient to prevent and treat nephrotoxicity and neurotoxicity with an acceptable tolerability profile. However, the high associated rejection rate indicates that great caution is required in its use during the immediate post-transplant period. It is advisable to associate the regimen with low doses of CNI and to have agile methods available to monitor EVL to enable rapid dose adjustment.

Everolimus in de novo liver transplant recipients: a systematic review

BACKGROUND

Everolimus has no nephrotoxicity and is used to treat patients with post-liver transplant chronic renal insufficiency. The present systematic review was to evaluate the efficacy and safety of everolimus in de novo liver transplant patients.

DATA SOURCES

Randomized controlled trials comparing everolimus for de novo liver transplant in PubMed, the Cochrane Library, and ScienceDirect published up to March 31, 2014 were searched by two independent reviewers. Mean differences and 95% confidence interval (95% CI) for renal function, relative risk (RR) and 95% CI for treated biopsy-proven acute rejection (tBPAR), graft loss, death, neoplasms/tumor recurrence, and adverse events were collected. Meta-analyses were performed with RevMan version 5.10.

RESULTS

A total of four randomized controlled trials covering 1119 cases were included. The meta-analyses revealed that compared with standard exposure of calcineurin inhibitors (CNIs), everolimus combined with reduced CNIs improved creatinine clearance (calculated with the Cockcroft-Gault formula) by 5.13 mL/min at one year (95% CI: 0.42-9.84; P=0.03), and decreased tBPAR (RR: 0.56; 95% CI: 0.35-0.90; P=0.02). Everolimus initiation with CNIs elimination improved glomerular filtration rate (GFR, measured with the modification of diet in renal disease formula) of 10.42 mL/min/1.73 m2 (95% CI: 3.44-17.41; P<0.01) one year after treatment, but increased tBPAR (RR: 1.71; 95% CI: 1.15-2.53; P<0.01). Everolimus decreased the risk of neoplasms/tumor recurrence after liver transplant (RR: 0.60; 95% CI: 0.34-1.03; P=0.06), but was associated with greater risk of adverse events which resulted in drug discontinuation (RR: 1.98; 95% CI: 1.49-2.64; P<0.01).

CONCLUSIONS

Early introduction of everolimus combined with low-dose or no CNI in de novo liver transplant significantly improves renal function one year post treatment. Everolimus combined with low-dose CNI decreases the risk of tBPAR one year after liver transplant, but everolimus administered without CNIs increases tBPAR.

Chronic Kidney Disease and Related Long-Term Complications After Liver Transplantation

Liver transplantation is the standard of care for patients with decompensated cirrhosis. Liver transplantation recipients have excellent short-term and long-term outcomes including patient and graft survival. Since the adoption of model for end-stage liver disease (MELD)-based allocation policy, the incidence of post-transplant end stage renal disease has risen significantly. Occurrence of Stage 4 chronic kidney disease and end stage renal disease substantially increases the risk of post-transplant deaths. Because majority of late post-transplant mortality is due to nonhepatic post-transplant comorbidities, personalized care directed toward risk factor modification may further improve post-transplant survival.

Renal function improvement in liver transplant recipients after early everolimus conversion: A clinical practice cohort study in Spain

A national, multicenter, retrospective study was conducted to assess the results obtained for liver transplant recipients with conversion to everolimus in daily practice. The study included 477 recipients (481 transplantations). Indications for conversion to everolimus were renal dysfunction (32.6% of cases), hepatocellular carcinoma (HCC; 30.2%; prophylactic treatment for 68.9%), and de novo malignancy (29.7%). The median time from transplantation to conversion to everolimus was 68.7 months for de novo malignancy, 23.8 months for renal dysfunction, and 7.1 months for HCC and other indications. During the first year of treatment, mean everolimus trough levels were 5.4 (standard deviation [SD], 2.7) ng/mL and doses remained stable (1.5 mg/day) from the first month after conversion. An everolimus monotherapy regimen was followed by 28.5% of patients at 12 months. Patients with renal dysfunction showed a glomerular filtration rate (4-variable Modification of Diet in Renal Disease) increase of 10.9 mL (baseline mean, 45.8 [SD, 25.3] versus 57.6 [SD, 27.6] mL/minute/1.73 m(2) ) at 3 months after everolimus initiation (P < 0.001), and 6.8 mL at 12 months. Improvement in renal function was higher in patients with early conversion (<1 year). Adverse events were the primary reason for discontinuation in 11.2% of cases. The probability of survival at 3 years after conversion to everolimus was 83.0%, 71.1%, and 59.5% for the renal dysfunction, de novo malignancy, and HCC groups, respectively. Everolimus is a viable option for the treatment of renal dysfunction, and earlier conversion is associated with better recovery of renal function. Prospective studies are needed to confirm advantages in patients with malignancy.

From immunosuppression to tolerance

The past three decades have seen liver transplantation becoming a major therapeutic approach in the management of end-stage liver diseases. This is due to the dramatic improvement in survival after liver transplantation as a consequence of the improvement of surgical and anaesthetic techniques, of post-transplant medico-surgical management and of prevention of disease recurrence and other post-transplant complications. Improved use of post-transplant immunosuppression to prevent acute and chronic rejection is a major factor in these improved results. The liver has been shown to be more tolerogenic than other organs, and matching of donor and recipients is mainly limited to ABO blood group compatibility. However, long-term immunosuppression is required to avoid severe acute and chronic rejection and graft loss. With the current immunosuppression protocols, the risk of acute rejection requiring additional therapy is 10-40% and the risk of chronic rejection is below 5%. However, the development of histological lesions in the graft in long-term survivors suggest atypical forms of graft rejection may develop as a consequence of under-immunosuppression. The backbone of immunosuppression remains calcineurin inhibitors (CNI) mostly in association with steroids in the short-term and mycophenolate mofetil or mTOR inhibitors (everolimus). The occurrence of post-transplant complications related to the immunosuppressive therapy has led to the development of new protocols aimed at protecting renal function and preventing the development of de novo cancer and of dysmetabolic syndrome. However, there is no new class of immunosuppressive drugs in the pipeline able to replace current protocols in the near future. The aim of a full immune tolerance of the graft is rarely achieved since only 20% of selected patients can be weaned successfully off immunosuppression. In the future, immunosuppression will probably be more case oriented aiming to protect the graft from rejection and at reducing the risk of disease recurrence and complications related to immunosuppressive therapy. Such approaches will include strategies aiming to promote stable long-term immunological tolerance of the liver graft.

Evaluating the efficacy, safety and evolution of renal function with early initiation of everolimus-facilitated tacrolimus reduction in de novo liver transplant recipients: Study protocol for a randomized controlled trial

BACKGROUND

Introduction of calcineurin inhibitors had led to improved survival rates in liver transplant recipients. However, long-term use of calcineurin inhibitors is associated with a higher risk of chronic renal failure, neurotoxicity, de novo malignancies, recurrence of hepatitis C viral (HCV) infection and hepatocellular carcinoma. Several studies have shown that everolimus has the potential to provide protection against viral replication, malignancy, and progression of fibrosis, as well as preventing nephrotoxicity by facilitating calcineurin inhibitor reduction without compromising efficacy. The Hephaistos study evaluates the beneficial effects of early initiation of everolimus in de novo liver transplant recipients.

METHODS/DESIGN

Hephaistos is an ongoing 12-month, multi-center, open-label, controlled study aiming to enroll 330 de novo liver transplant recipients from 15 centers across Germany. Patients are randomized in a 1:1 ratio (7-21 days post-transplantation) to receive everolimus (trough levels 3-8 ng/mL) with reduced tacrolimus (trough levels <5 ng/mL), or standard tacrolimus (trough levels 6-10 ng/mL) after entering a run-in period (3-5 days post-transplantation). In the run-in period, patients are treated with induction therapy, mycophenolate mofetil, tacrolimus, and corticosteroids according to local practice. Randomization is stratified by HCV status and model of end-stage liver disease scores at transplantation. The primary objective of the study is to exhibit superior renal function (estimated glomerular filtration rate assessed by the Modification of Diet in Renal Disease (MDRD)-4 formula) with everolimus plus reduced tacrolimus compared to standard tacrolimus at Month 12. Other objectives are: to assess the incidence of treated biopsy-proven acute rejection, graft loss, or death; the incidences of components of the composite efficacy endpoint; renal function via estimated glomerular filtration rate using various formulae (MDRD-4, Nankivell, Cockcroft-Gault, chronic kidney disease epidemiology collaboration and Hoek formulae); the incidence of proteinuria; the incidence of adverse events and serious adverse events; the incidence and severity of cytomegalovirus and HCV infections and HCV-related fibrosis.

DISCUSSION

This study aims to demonstrate superior renal function, comparable efficacy, and safety in de novo liver transplant recipients receiving everolimus with reduced tacrolimus compared with standard tacrolimus. This study also evaluates the antiviral benefit by early initiation of everolimus.

TRIAL REGISTRATION

NCT01551212 .

Experience of using everolimus in the early stage of living donor liver transplantation

OBJECTIVES

The aim of our study was to review the experience of early use of everolimus for recipients after adult-to-adult living donor liver transplantation.

METHODS

From February 2012 to December 2012, 80 recipients underwent living donor liver transplantation. Forty-three of them used everolimus as an adjunct to the calcineurin inhibitors (CNIs) in the early postoperative period. Thirty-nine patients had hepatocellular carcinoma (HCC) and poor renal function was noted in 9 patients. Ten of them were females and 33 were males. The age varied from 39 to 75 years old. The starting date of use was within 1 week in 33 patients, 2 weeks in 9 patients, and 1 patient was administered on postoperative day 20. The initial doses of everolimus were 0.25 mg every 12 hours and increased to 0.5 mg every 12 hours to target the level at 3-5 ng/mL. Doppler ultrasound was performed regularly postoperative days 1, 4, and 14.

RESULTS

The mean time between liver transplantation and everolimus treatment was 12 ± 8 days. The maximum dose of everolimus used was 1 mg/d with a target trough level between 3 and 5 ng/mL. At 3 months, a target trough level of 3 ng/mL was achieved. Six of 9 renal failure patients showed significant recovery of renal function, whereas 3 of them showed further deterioration and 1 required hemodialysis. During the follow-up period of 9 ± 6 months, all showed good patency of hepatic artery without thrombosis. Three patients (7%) developed HCC recurrence, whereas 1 patient died at the 10th month postoperative due to sepsis. Elevation of lipid profile was noted in 5 patients. Stomatitis was the most frequent side effect and occurred in 15 patients.

CONCLUSIONS

The early use of everolimus was safe and feasible. Also, it can be safely used in patients with prior renal failure while reducing the doses of CNIs. Although the recurrence rate of HCC was reduced, further study is ongoing to evaluate the long-term impact of everolimus on prevention of HCC recurrence.

The role of everolimus in liver transplantation

During the last 5 decades, liver transplantation has witnessed rapid development in terms of both technical and pharmacologic advances. Since their discovery, calcineurin inhibitors (CNIs) have remained the standard of care for immunosuppression therapy in liver transplantation, improving both patient and graft survival. However, adverse events, particularly posttransplant nephrotoxicity, associated with long-term CNI use have necessitated the development of alternate treatment approaches. These include combination therapy with a CNI and the inosine monophosphate dehydrogenase inhibitor mycophenolic acid and use of mammalian target of rapamycin (mTOR) inhibitors. Everolimus, a 40-O-(2-hydroxyethyl) derivative of mTOR inhibitor sirolimus, has a distinct pharmacokinetic profile. Several studies have assessed the role of everolimus in liver transplant recipients in combination with CNI reduction or as a CNI withdrawal strategy. The efficacy of everolimus-based immunosuppressive therapy has been demonstrated in both de novo and maintenance liver transplant recipients. A pivotal study in 719 de novo liver transplant recipients formed the basis of the recent approval of everolimus in combination with steroids and reduced-dose tacrolimus in liver transplantation. In this study, everolimus introduced at 30 days posttransplantation in combination with reduced-dose tacrolimus (exposure reduced by 39%) showed comparable efficacy (composite efficacy failure rate of treated biopsy-proven acute rejection, graft loss, or death) and achieved superior renal function as early as month 1 and maintained it over 2 years versus standard exposure tacrolimus. This review provides an overview of the efficacy and safety of everolimus-based regimens in liver transplantation in the de novo and maintenance settings, as well as in special populations such as patients with hepatocellular carcinoma recurrence, hepatitis C virus-positive patients, and pediatric transplant recipients. We also provide an overview of ongoing studies and discuss potential expansion of the role for everolimus in these settings.

mTOR inhibitors and dyslipidemia in transplant recipients: a cause for concern?

Post-transplant dyslipidemia is exacerbated by mammalian target of rapamycin (mTOR) inhibitors. Early clinical trials of mTOR inhibitors used fixed dosing with no concomitant reduction in calcineurin inhibitor (CNI) exposure, leading to concerns when consistent and marked dyslipidemia was observed. With use of modern concentration-controlled mTOR inhibitor regimens within CNI-free or reduced-exposure CNI regimens, however, the dyslipidemic effect persists but is less pronounced. Typically, total cholesterol levels are at the upper end of normal, or indicate borderline risk, in kidney and liver transplant recipients, and are lower in heart transplant patients under near-universal statin therapy. Of note, it is possible that mTOR inhibitors may offer a cardioprotective effect. Experimental evidence for delayed progression of atherosclerosis is consistent with evidence from heart transplantation that coronary artery intimal thickening and the incidence of cardiac allograft vasculopathy are reduced with everolimus versus cyclosporine therapy. Preliminary data also indicate that mTOR inhibitors may improve arterial stiffness, a predictor of cardiovascular events, and may reduce ventricular remodeling and decrease left ventricular mass through an anti-fibrotic effect. Post-transplant dyslipidemia under mTOR inhibitor therapy should be monitored and managed closely, but unless unresponsive to therapy should not be regarded as a barrier to its use.

Mammalian target of rapamycin inhibitors are associated with lower rates of hepatocellular carcinoma recurrence after liver transplantation: a systematic review

Calcineurin inhibitors (CNIs) have been associated in a dose-dependent fashion with an increased risk of post-transplant hepatocellular carcinoma (HCC) recurrence. The mammalian target of rapamycin inhibitors (mTORi) (sirolimus/everolimus) might represent an alternative immunosuppressive regimen with antineoplastic effect. In the present systematic review, the association between mTORi and HCC recurrence after liver transplantation (LT) was evaluated and compared against that of CNIs-treated patients. In total, 3666 HCC liver transplant recipients from 42 studies met the inclusion criteria. Patients under CNIs developed HCC recurrence significantly more frequently, compared with patients under mTORi (448/3227 or 13.8% vs. 35/439 or 8%, P < 0.001), although patients treated with CNIs had a higher proportion of HCC within Milan criteria (74% vs. 69%) and lower rates of microvascular invasion, compared with mTORi-treated patients (22% vs. 44%) (P < 0.05). Patients on everolimus had significantly lower recurrence rates of HCC, compared with those on sirolimus or CNIs (4.1% vs. 10.5% vs. 13.8%, respectively, P < 0.05), but everolimus-treated recipients had shorter follow-up period (13 vs. 30 vs. 43.2 months, respectively) and more frequently been transplanted for HCC within Milan criteria (84% vs. 60.5% vs. 74%, respectively, P < 0.05). Our findings favor the use of mTORi instead of CNIs to control HCC recurrence after LT, but comparative studies with longer follow-up are needed for final conclusions.

Multiple indications for everolimus after liver transplantation in current clinical practice

AIM: To assess our experience with the use and management of everolimus-based regimens post-liver transplantation and to redefine the potential role of this drug in current clinical practice.

METHODS: From October 1988 to December 2012, 1023 liver transplantations were performed in 955 patients in our Unit. Seventy-four patients (7.74%) received immunosuppression with everolimus at some time post-transplantation. Demographic characteristics, everolimus indication, time elapsed from transplantation to the introduction of everolimus, doses and levels administered, efficacy, side effects, discontinuation and post-conversion survival were analyzed.

RESULTS: Mean age at the time of conversion to everolimus was 57.7 ± 10 years. Indications for conversion were: refractory rejection 31.1%, extended hepatocellular carcinoma in explanted liver 19%, post-transplant hepatocellular carcinoma recurrence 8.1%, de novo tumour 17.6%, renal insufficiency 8.1%, severe neurotoxicity 10.8%, and others 5.4%. Median time from transplantation to introduction of everolimus was 6 mo (range: 0.10-192). Mean follow-up post-conversion was 22 ± 19 mo (range: 0.50-74). The event for which the drug was indicated was resolved in 60.8% of patients, with the best results in cases of refractory rejection, renal insufficiency and neurotoxicity. Results in patients with cancer were similar to those of a historical cohort treated with other immunosuppressants. The main side effects were dyslipidemia and infections. Post-conversion acute rejection occurred in 14.9% of cases. The drug was discontinued in 28.4% of patients.

CONCLUSION: Everolimus at low doses in combination with tacrolimus is a safe immunosuppressant with multiple early and late indications post-liver transplantation.

Current strategies for immunosuppression following liver transplantation

BACKGROUND

New strategies for immunosuppression (IS) after liver transplantation (LTx) are in part responsible for the increased patient and graft survival seen over time. With a few basic exceptions-notably the continued use of steroids and calcineurin inhibitors (CNIs)-IS drugs and regimens being used today are different from those used 30 years ago. While graft loss due to acute or chronic rejection has become rare, the side effect burden of IS drugs exerts a significant toll on patients.

CONCEPTS/TRENDS

CNIs continue to form the backbone of IS regimens, although their use is hampered by nephrotoxicity and other adverse effects. Consequently, a variety of CNI reduction or withdrawal strategies have formed the basis of clinical trials or entered into clinical practice. These trials have included the use of everolimus, an mTOR inhibitor, and anti-interleukin-2 receptor antibodies. Basiliximab, as well as other lymphocyte nondepleting and depleting agents, have shown benefit in induction regimens.

SUMMARY

Along with steroid reduction or elimination, current strategies for IS after LTx continue to explore novel combinations of agents, with an aim toward striking a balance between diminution of rejection and the need for avoiding adverse effects of the IS drugs. Long-term maintenance strategies are also discussed in this review, as is development of tolerance and antibody-mediated rejection.

The Role of mTOR Inhibitors in Liver Transplantation: Reviewing the Evidence

Despite the success of liver transplantation, long-term complications remain, including de novo malignancies, metabolic syndrome, and the recurrence of hepatitis C virus (HCV) and hepatocellular carcinoma (HCC). The current mainstay of treatment, calcineurin inhibitors (CNIs), can also worsen posttransplant renal dysfunction, neurotoxicity, and diabetes. Clearly there is a need for better immunosuppressive agents that maintain similar rates of efficacy and renal function whilst minimizing adverse effects. The mammalian target of rapamycin (mTOR) inhibitors with a mechanism of action that is different from other immunosuppressive agents has the potential to address some of these issues. In this review we surveyed the literature for reports of the use of mTOR inhibitors in adult liver transplantation with respect to renal function, efficacy, safety, neurological symptoms, de novo tumors, and the recurrence of HCC and HCV. The results of our review indicate that mTOR inhibitors are associated with efficacy comparable to CNIs while having benefits on renal function in liver transplantation. We also consider newer dosing schedules that may limit side effects. Finally, we discuss evidence that mTOR inhibitors may have benefits in the oncology setting and in relation to HCV-related allograft fibrosis, metabolic syndrome, and neurotoxicity.

Everolimus monotherapy or combined therapy in liver transplantation: indications and results

INTRODUCTION

Everolimus is a potent immunosuppressant with several advantages over calcineurin inhibitors, such as good tolerance, preventive effects on cardiovascular morbidity, and mortality and cancer prevention as it inhibits cell proliferation.

PATIENTS AND METHODS

Between April 1986 and December 2010, we performed 1500 liver transplants (OLT) in 1341 recipients, including 57 patients who were prescribed everolimus 24 (42.1%) as monotherapy and 33 (57.9%) as treatments combined with other immunosuppressants. We performed a retrospective analysis of our experience with conversion to everolimus in OLT recipients.

RESULTS

The 43 men and 14 women had a mean overall age at transplantation of 59.1 ± 10 years. The most frequent indication for OLT was hepatocellular carcinoma (HCC; 53.8%). Everolimus was introduced to prevent HCC recurrence (53%), development of de novo tumors (33%), address renal dysfunction (7%), or overcome side effects of other immunosuppressants (7%). We observed a significant improvement in renal function using the estimated glomerular filtration rate (Crockcroft-Gault formula) from 68.5 mL/min before to 74.5 mL/min after switching to everolimus. The 72% of recipients who developed ≥1 adverse event, most frequently showed hyperlipidemia (34.4%).

CONCLUSION

Both monotherapy and combined everolimus regimens were well-tolerated immunosuppressive regimens in liver transplant recipients with recurrent or de novo malignancies. Everolimus improved renal function. The most common side effects were hyperlipidemia, edema, and mouth ulcerations, which were well controlled with anti-lipidemic agents or decreased everolimus dosages.