Everolimus with reduced tacrolimus improves renal function in de novo liver transplant recipients: a randomized controlled trial

Association between everolimus combination therapy and cancer risk after liver transplantation: A nationwide population-based quasi-cohort study

The potential of everolimus (EVR) in reducing hepatocellular carcinoma (HCC) among recipients following liver transplantation has been reported. This nationwide population-based quasi-cohort study investigated whether combining EVR with calcineurin inhibitor therapy affects the risk of HCC and extrahepatic cancers compared to a time duration-matched cohort of recipients not receiving EVR. Using data covering the entire population from Korea, liver transplant recipients who had initiated immunosuppressants between June 2015 and February 2020 were included, and divided into 2 groups: the EVR combination and noncombination groups. We calculated adjusted hazard ratios (aHRs) and absolute risk reduction for the risk of HCC and extrahepatic cancer with EVR combination therapy using a Cox regression model. A time duration-matched retrospective cohort of 932 recipients in both of the groups was identified. The EVR combination group showed a lower risk of HCC (aHR, 0.53; 95% confidence interval, 0.30-0.94) and extrahepatic cancers (aHR, 0.30; 95% confidence interval, 0.14-0.63) compared to the noncombination group. The absolute risk reduction was 0.004 for HCC and 0.012 for extrahepatic cancer. The findings suggest that adding EVR to calcineurin inhibitor therapy reduces cancer risk in liver transplant recipients, highlighting the importance of considering cancer risk when choosing immunosuppressive therapies.

Optimization and Protection of Kidney Health in Liver Transplant Recipients: Intra- and Postoperative Approaches

Postoperative acute kidney injury after liver transplant (LT) has long-term implications for kidney health. LT recipients are at risk of acute kidney injury due to a number of factors related to the donor liver, intraoperative factors including surgical technique, as well as recipient factors, such as pre-LT kidney function and postoperative complications. This review discusses these factors in detail and their impact on posttransplant kidney function. Long-term risk factors such as calcineurin inhibitors have also been discussed. Additionally, the impact of liver allocation policies on pre- and post-LT kidney health is discussed.

Everolimus Personalized Therapy: Second Consensus Report by the International Association of Therapeutic Drug Monitoring and Clinical Toxicology

ABSTRACT

The Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology established the second consensus report to guide therapeutic drug monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice 7 years after the first version was published in 2016. This version provides information focused on new developments that have arisen in the last 7 years. For the general aspects of the pharmacology and TDM of EVR that have retained their relevance, readers can refer to the 2016 document. This edition includes new evidence from the literature, focusing on the topics updated during the last 7 years, including indirect pharmacological effects of EVR on the mammalian target of rapamycin complex 2 with the major mechanism of direct inhibition of the mammalian target of rapamycin complex 1. In addition, various concepts and technical options to monitor EVR concentrations, improve analytical performance, and increase the number of options available for immunochemical analytical methods have been included. Only limited new pharmacogenetic information regarding EVR has emerged; however, pharmacometrics and model-informed precision dosing have been constructed using physiological parameters as covariates, including pharmacogenetic information. In clinical settings, EVR is combined with a decreased dose of calcineurin inhibitors, such as tacrolimus and cyclosporine, instead of mycophenolic acid. The literature and recommendations for specific organ transplantations, such as that of the kidneys, liver, heart, and lungs, as well as for oncology and pediatrics have been updated. EVR TDM for pancreatic and islet transplantation has been added to this edition. The pharmacodynamic monitoring of EVR in organ transplantation has also been updated. These updates and additions, along with the previous version of this consensus document, will be helpful to clinicians and researchers treating patients receiving EVR.

Bibliometric and LDA analysis of acute rejection in liver transplantation: Emerging trends, immunotherapy challenges, and the role of artificial intelligence

With the rising demand for liver transplantation (LT), research on acute rejection (AR) has become increasingly diverse, yet no consensus has been reached. This study presents a bibliometric and latent Dirichlet allocation (LDA) topic modeling analysis of AR research in LT, encompassing 1399 articles. The United States, Zhejiang University, and the University of California, San Francisco emerged as leading contributors, while Levitsky J and Uemoto SJ were key researchers. The most influential journals included the American Journal of Transplantation, Journal of Hepatology, and Transplantation. The analysis reveals a transition from traditional histological assessments to molecular diagnostics, genetic and epigenetic profiling, and noninvasive biomarkers such as donor-derived cell-free DNA (dd-cfDNA) and microRNAs. Advances in immune checkpoint inhibitors (ICIs), cell-based therapies (Tregs, mesenchymal stem cells (MSCs)), AI-guided immunosuppression, and nanoparticle-mediated drug delivery systems reflect a growing emphasis on precision medicine. In addition, recent exploration of microbiome-based therapies and regenerative medicine, including MSCs and their extracellular vesicles, offers promising new avenues for reducing long-term immunosuppressive drug dependency and enhancing graft survival. These developments not only improve early AR detection and personalized treatment but also reduce toxicity, foster immune tolerance, and expand the scope of individualized therapeutic options. Global collaboration, supported by cutting-edge research and AI-driven decision-making, remains essential for refining AR strategies, improving graft survival, and achieving better long-term patient outcomes.

Optimal tacrolimus levels for reducing CKD risk and the impact of intrapatient variability on CKD and ESRD development following liver transplantation

BACKGROUND/AIMS

This study aimed to identify the risk factors for chronic kidney disease (CKD) and end-stage renal disease (ESRD) following liver transplantation (LT), with a specific focus on tacrolimus levels and intrapatient variability (IPV).

METHODS

Among the 1,076 patients who underwent LT between 2000 and 2018, 952 were included in the analysis. The tacrolimus doses and levels were recorded every 3 months, and the IPV was calculated using the coefficient of variability. The cumulative incidence rates of CKD and ESRD were calculated based on baseline kidney function at the time of LT. The impact of tacrolimus levels and their IPV on the development of CKD and ESRD was evaluated, and the significant risk factors were identified.

RESULTS

Within a median follow-up of 97.3 months, the 5-year cumulative incidence rates of CKD (0.58 vs. 0.24) and ESRD (0.07 vs. 0.01) were significantly higher in the acute kidney injury group than in the normal glomerular filtration rate (GFR) group. In the normal GFR group, the tacrolimus levels were identified as a risk factor for CKD, with a level of ≤4.5 ng/mL suggested as optimal for minimizing the risk of CKD. Furthermore, the IPV of tacrolimus levels and doses emerged as a significant risk factor for CKD development in both groups (p<0.05), with tenofovir disoproxil fumarate also being a risk factor in HBV-infected patients. The IPV of tacrolimus levels was also a significant factor in ESRD development (p<0.05).

CONCLUSION

This study elucidated the optimal tacrolimus trough level and highlighted the impact of IPV on the CKD and ESRD development post-LT.

Advancing immunosuppression in liver transplantation: the role of regulatory T cells in immune modulation and graft tolerance

Prolonged immunosuppressive therapy in liver transplantation (LT) is associated with significant adverse effects, such as nephrotoxicity, metabolic complications, and heightened risk of infection or malignancy. Regulatory T cells (Tregs) represent a promising target for inducing immune tolerance in LT, with the potential to reduce or eliminate the need for life-long immunosuppression. This review summarizes current knowledge on the roles of Tregs in LT, highlighting their mechanisms and the impact of various immunosuppressive agents on Treg stability and function. The liver's distinct immunological microenvironment, characterized by tolerogenic antigen-presenting cells and high levels of interleukin (IL)-10 and transforming growth factor-β, positions this organ as an ideal setting for Treg-mediated tolerance. We discuss Treg dynamics in LT, their association with rejection risk, and their utility as biomarkers of transplant outcomes. Emerging strategies, including the use of low-dose calcineurin inhibitors with mammalian target of rapamycin inhibitors, adoptive Treg therapy, and low-dose IL-2, aim to enhance Treg function while providing sufficient immunosuppression. Thus, the future of LT involves precision medicine approaches that integrate Treg monitoring with tailored immunosuppressive protocols to optimize long-term outcomes for LT recipients.

Estimation of lifetime costs for patients receiving a transplant: the case of liver transplantation related to hepatitis B in Italy

Introduction

In Italy, post-liver transplant (LT) hepatitis B virus (HBV) reinfection prophylaxis is frequently based on a combined regimen of anti-HBV immunoglobulin (HBIG) and oral antivirals. However, little information is available at the national level on the cost of LT and the contribution of HBV prophylaxis. This study aimed to quantify the direct healthcare cost for adult patients undergoing LT for HBV-related disease over a lifetime horizon and from the perspective of a National Healthcare Service.

Methods

A pharmaco-economic model was implemented with a 4-tiered approach consisting of 1) preliminary literature research to define the research question; 2) pragmatic literature review to retrieve existing information and inform the model; 3) micro-simulated patient cycles; and 4) validation from a panel of national experts.

Results

The average lifetime healthcare cost of LT for HBV-related disease was €395,986. The greatest cost drivers were post-transplant end-stage renal failure (31.9% of the total), immunosuppression (20.6%), and acute transplant phase (15.8%). HBV reinfection prophylaxis with HBIG and antivirals accounted for 12.4% and 6.4% of the total cost, respectively; however, lifetime HBIG prophylaxis was only associated with a 6.6% increase (~€422 k). Various sensitivity analyses have shown that discount rates have the greatest impact on total costs.

Conclusion

This analysis showed that the burden of LT due to HBV is not only clinical but also economic.

Early Conversion to Everolimus Within 180 Days of Living Donor Liver Transplantation

BACKGROUND

Early conversion to Everolimus (EVR) post deceased donor liver transplant has been associated with improved renal function but increased rejection. Early EVR conversion has not been evaluated after living donor liver transplant (LDLT). A retrospective cohort study was conducted to compare the rate of rejection and renal function in patients converted to EVR early post-LDLT to patients on calcineurin inhibitors (CNIs).

METHODS

This was a single center retrospective cohort study of adult LDLT recipients between January 2012 and July 2019. Patients converted to EVR within 180 days of transplant were compared to patients on CNIs. The primary endpoint was biopsy proven acute rejection (BPAR) at 24 months posttransplant. Key secondary endpoints included eGFR at 24 months, change in eGFR, adverse events, and all-cause mortality.

RESULTS

From a total of 173 patients involved in the study: 58 were included in the EVR group and 115 in the CNI group. Median conversion to EVR was 26 days post-LDLT. At 24 months, there was no difference in BPAR (22.7% EVR vs. 19.1% CNI, p = 0.63). Median eGFR at 24 months posttransplant was not significantly different (68.6 [24.8 to 112.4] mL/min EVR vs. 75.9 [35.6-116.2] mL/min CNI, p = 0.103). Change in eGFR from baseline was worse in the EVR group (-13.0 [-39.9 to 13.9] mL/min EVR vs. -5.0 [-31.2 to 21.2] mL/min CNI, p = 0.047). Median change from conversion to 24 months posttransplant (EVR group only) was -3.43 mL/min/1.73 m2 (-21.0 to 9.6).

CONCLUSIONS

Early EVR conversion was not associated with increased risk of rejection among LDLT recipients. Renal function was not impacted. EVR may be considered as an alternative after LDLT in patients intolerant of CNIs.

Immunosuppression in liver transplant oncology: position paper of the Italian Board of Experts in Liver Transplantation (I-BELT)

Liver transplant oncology (TO) represents an area of increasing clinical and scientific interest including a heterogeneous group of clinical-pathological settings. Immunosuppressive management after LT is a key factor relevantly impacting result. However, disease-related guidance is still lacking, and many open questions remain in the field. Based on such a substantial lack of solid evidences, the Italian Board of Experts in Liver Transplantation (I-BELT) (a working group including representatives of all national transplant centers), unprecedently promoted a methodologically sound consensus conference on the topic, based on the GRADE approach. The group final recommendations are herein presented and commented. The 18 PICOs and Statements and their levels of evidence and grades of recommendation are reported and grouped into seven areas: (1) risk stratification by histopathological and bio-molecular parameters and role of mTORi post-LT; (2) steroids and HCC recurrence; (3) management of immunosuppression when HCC recurs after LT; (4) mTORi monotherapy; (5) machine perfusion and HCC recurrence after LT; (6) physiopathology of tumor-infiltrating lymphocytes and immunosuppression, the role of inflammation; (7) immunotherapy in liver transplanted patients. The interest in mammalian targets of rapamycin inhibitors (mTORi), for steroid avoidance and the need for a reduction to CNI exposure emerged from the consensus process. A selected list of unmet needs prompting further investigations have also been developed. The so far heterogeneous and granular approach to immunosuppression in oncologic patients deserves greater efforts for a more standardized therapeutic response to the different clinical scenarios. This consensus process makes a first unprecedented step in this direction, to be developed on a larger scale.

Recurrent rejections after liver transplantation for hepatocellular carcinoma with stem cell features in an adult patient

Patients with hepatoblastoma featuring carcinoma characteristics have better outcomes after liver transplantation, than after chemotherapy and resection. Possibly this should be extrapolated to aggressive subtypes of hepatocellular carcinomas in non-cirrhotic livers, where early liver transplantation might also be indicated. However, the risks associated with liver transplantation and immunosuppressive treatment after liver transplantation are once again demonstrated by this case of a 32-year-old women with a negative personal and familial history of liver diseases. She underwent transplantation (DBD) for a hepatocellular carcinoma with stem cell features (HCC-HS; an aggressive 'hepatoblast subtype' of hepatocellular carcinoma) after chemotherapeutical downstaging techniques failed to sufficiently downstage the tumor. Despite being on conventional immunosuppressive regimens (tacrolimus and mycophenolate mofetil with initial corticosteroids tapered), this patient still developed two severe rejection episodes, one of which necessitated retransplantation (DCD). Both episodes were preceded by alterations in tacrolimus trough levels, either intentionally, when tacrolimus was reduced within a nephroprotective regimen, or unintentionally, when rifampicin, a CYP3A4 inducer, significantly lowered the trough levels. Together, these episodes stress the importance of therapeutic drug monitoring of tacrolimus. Furthermore, the patient experienced an everolimus-linked drug-induced thrombotic microangiopathy, underwent multiple ERCPs for an anastomotic stricture and only one and a half year after the first liver transplantation she already suffers from long-term immunosuppressive-related side effects such as impaired glucose tolerance, hypertension and a potential cardiomyopathy. At present, she is still alive and experienced no recurrence of her primary tumor. Her case underscores the significant challenges in post-liver transplantation care.

Everolimus Mitigates the Risk of Hepatocellular Carcinoma Recurrence after Liver Transplantation

To obtain long-term data on the use of everolimus in patients who underwent liver transplantation for hepatocellular carcinoma, we conducted a retrospective, single-center analysis of adult recipients transplanted between 2013 and 2021. Patients on everolimus-incorporating immunosuppression were matched with those on tacrolimus using an inverse probability of treatment weighting methodology. Two propensity-matched groups of patients were thus compared: 233 (45.6%) receiving everolimus versus 278 (54.4%) on tacrolimus. At a median (interquartile range) follow-up of 4.4 (3.8) years after transplantation, everolimus patients showed a reduced risk of recurrence versus tacrolimus (7.7% versus 16.9%; RR = 0.45; p = 0.002). At multivariable analysis, microvascular infiltration (HR = 1.22; p < 0.04) and a higher tumor grading (HR = 1.27; p < 0.04) were associated with higher recurrence rate while being within Milan criteria at transplant (HR = 0.56; p < 0.001), a successful pre-transplant downstaging (HR = 0.63; p = 0.01) and use of everolimus (HR = 0.46; p < 0.001) had a positive impact on the risk of post-transplant recurrence. EVR patients with earlier drug introduction (≤30 days; p < 0.001), longer treatment duration (p < 0.001), and higher drug exposure (≥5.9 ng/mL; p < 0.001) showed lower recurrence rates versus TAC. Based on our experience, everolimus provides a reduction in the relative risk of hepatocellular carcinoma recurrence, especially for advanced-stage patients and those with earlier drug administration, higher drug exposure, and longer time on treatment. These data advocate for early everolimus introduction after liver transplantation to reduce the attrition rate consequent to chronic immunosuppression.

Current Use of Immunosuppression in Liver Transplantation

Since the first successful liver transplant in 1967, immunosuppression has allowed liver transplantation to become the standard treatment of end-stage liver disease. Over the decades, the rates of rejection have decreased, and patient survival outcomes have significantly improved in large part due to the introduction and advancements of immunosuppression medications. However, the adverse effects associated with long-term immunosuppression have created new challenges facing liver transplantation and added significantly to posttransplantation morbidity. This review presents the data and rationale for immunosuppression approaches, addresses the main controversies related to immunosuppression in liver transplantation, and explores some of the newer advancements in immunosuppressive drug therapy.

Long Term Complications of Immunosuppression Post Liver Transplant

Improvement in immunosuppression has led to a remarkable improvement in short-term and long-term outcomes post-liver transplant (LT). However, with improvements in long-term survival, complications related to immunosuppressive drugs, either directly or indirectly, have also increased. The adverse events could be drug-specific, class-specific, or generic. Calcineurin inhibitors (cyclosporine and tacrolimus) are the backbone of the immunosuppression after LT and the main culprit associated with most of the complications, including renal failure, post-transplant diabetes mellitus (PTDM), and metabolic syndrome. Steroids are also implicated in the development of diabetes, osteoporosis, and metabolic syndrome post-LT. The development of infections and de novo malignancies (DNMs) is a generic effect linked to the overall cumulative immunosuppression. The development of these complications significantly hampers the quality of life and leads to increased morbidity and mortality post-LT. Thus, it is important to minimize the cumulative immunosuppression dose while simultaneously preventing allograft rejection. This review provides up-to-date, comprehensive knowledge of the complications of long-term immunosuppression post-LT along with associated risk factors and strategies to minimize the risk of complications.

Chronic Kidney Disease After Liver Transplantation

Chronic kidney disease among liver transplant recipients is common and associated with an increased mortality risk. Several risk factors and causes for the development of chronic kidney disease have been identified. They can be divided into perioperative factors, such as unresolved acute kidney injury; donor-related factors, such as the use of extended criteria liver allografts; and recipient-related factors, such as the use of calcineurin inhibitors and the presence of metabolic syndrome, diabetes, and obesity. There is a bimodal progression, more prominent during the initial post-transplant months, followed by a gradual but progressive decline over the subsequent years. Management strategies to prevent and treat chronic kidney disease in the general population can be reasonably applied to the liver transplant population and include addressing comorbidities such as hypertension and diabetes. Strategies to minimize or withdraw calcineurin inhibitors from the immunosuppressive regimen can slow progression of kidney dysfunction. Patients with advanced chronic kidney disease should be considered for kidney transplantation due to its survival advantage. Allocation policy in the United States confers safety-net allocation priority for liver transplant recipients who develop advanced chronic kidney disease within the first year of liver transplantation.

The Renal Histological Correlates of Refractory Renal Dysfunction After Liver Transplantation

Background

Kidney dysfunction is common after liver transplantation (LT) and is often attributed to calcineurin inhibitors (CNIs). Very few studies have looked at histological causes.

Material and methods

The study is a retrospective analysis of histological findings and diagnosis in all patients who underwent a kidney biopsy after LT from 2010 to 2020. Data are shown as mean ± standard deviation or medians (25-75 interquartile range).

Results

The study cohort consisted of 26 patients (25 males, 1 female), aged 55 ± 7 years at the time of the kidney biopsy. Kidney biopsies were done at 27.5 (6.7-60.7) months after LT. At the time of the kidney biopsy, the median serum creatinine was 2.10 (1.50-2.86) mg/dl and proteinuria was 3.8 (1.8-5.9) gm/day. Twenty-four (92%) patients were on CNIs. The diagnoses on kidney biopsies were diabetic nephropathy (n = 7), focal segmental glomerulosclerosis (n = 4), CNI nephrotoxicity (n = 3), IgA nephropathy (n = 4), chronic glomerulonephritis (n = 3), hypertensive nephropathy (n = 1), membranous glomerulonephritis (n = 1), acute on chronic interstitial nephritis (n = 1), and C1q nephropathy (n = 1), and the sample was inadequate in one patient. A total of sixteen patients had progression of kidney disease. The kidney function remained stable/improved in 6 (23%) patients, follow-up data were not available for 4 patients. Fourteen (53.8%) patients (including one with CNI nephrotoxicity) required hemodialysis at 13.5 (5.7-29) months after the kidney biopsy.

Conclusion

Although the kidney biopsy diagnosed the cause of unexplained renal insufficiency in LT recipients, the majority of patients progressed to end-stage renal disease despite treatment modifications. The use of CNIs was an uncommon cause of renal impairment.

The Role of mTOR Inhibitors after Liver Transplantation for Hepatocellular Carcinoma

Liver transplantation is a treatment option for nonresectable patients with early-stage HCC, with more significant advantages when Milan criteria are fulfilled. An immunosuppressive regimen is required to reduce the risk of graft rejection after transplantation, and CNIs represent the drugs of choice in this setting. However, their inhibitory effect on T-cell activity accounts for a higher risk of tumour regrowth. mTOR inhibitors (mTORi) have been introduced as an alternative immunosuppressive approach to conventional CNI-based regimens to address both immunosuppression and cancer control. The PI3K-AKT-mTOR signalling pathway regulates protein translation, cell growth, and metabolism, and the pathway is frequently deregulated in human tumours. Several studies have suggested the role of mTORi in reducing HCC progression after LT, accounting for a lower recurrence rate. Furthermore, mTOR immunosuppression controls the renal damage associated with CNI exposure. Conversion to mTOR inhibitors is associated with stabilizing and recovering renal dysfunction, suggesting an essential renoprotective effect. Limitations in this therapeutic approach are related to their negative impact on lipid and glucose metabolism as well as on proteinuria development and wound healing. This review aims to summarize the roles of mTORi in managing patients with HCC undergoing LT. Strategies to overcome common adverse effects are also proposed.

Liver transplantation immunology: Immunosuppression, rejection, and immunomodulation

Outcomes after liver transplantation have continuously improved over the past decades, but long-term survival rates are still lower than in the general population. The liver has distinct immunological functions linked to its unique anatomical configuration and to its harbouring of a large number of cells with fundamental immunological roles. The transplanted liver can modulate the immunological system of the recipient to promote tolerance, thus offering the potential for less aggressive immunosuppression. The selection and adjustment of immunosuppressive drugs should be individualised to optimally control alloreactivity while mitigating toxicities. Routine laboratory tests are not accurate enough to make a confident diagnosis of allograft rejection. Although several promising biomarkers are being investigated, none of them is sufficiently validated for routine use; hence, liver biopsy remains necessary to guide clinical decisions. Recently, there has been an exponential increase in the use of immune checkpoint inhibitors due to the unquestionable oncological benefits they provide for many patients with advanced-stage tumours. It is expected that their use will also increase in liver transplant recipients and that this might affect the incidence of allograft rejection. Currently, the evidence regarding the efficacy and safety of immune checkpoint inhibitors in liver transplant recipients is limited and cases of severe allograft rejection have been reported. In this review, we discuss the clinical relevance of alloimmune disease, the role of minimisation/withdrawal of immunosuppression, and provide practical guidance for using checkpoint inhibitors in liver transplant recipients.

Combination of everolimus and low-dose tacrolimus controls histological liver allograft injury as sufficiently as high-dose tacrolimus

Introduction

The combination of everolimus (EVR) and low-dose tacrolimus (lowTAC) prevents T cell-mediated rejection of liver grafts as sufficiently as high-dose tacrolimus (highTAC) and mycophenolate, but is associated with a preserved kidney function within the first years after orthotopic liver transplantation (OLT). However, none of the available studies assessed the histological pattern of graft injury or fibrosis in surveillance biopsies (svLbx).

Methods

All svLbx taken under at least one month of stable immunosuppression with either EVR (aim 3-8 ng/ml) combined with lowTAC (aim 3-5 ng/ml) or highTAC (aim 5-8 ng/ml) combined with mycophenolate (500-1500 mg/day) within the first three to four years after OLT at our center were included. Patients who were switched to EVR because of insufficient control of alloreactivity were excluded.

Results

Reasons for switches to EVR were mainly malignancies before or after OLT, or chronic kidney injury. We were able to include 20 svLbx with EVR/lowTAC and 49 with highTAC/mycophenolate. Both groups had similar liver enzymes and similar kidney function. The EVR/lowTAC group exhibited lower TAC trough levels at svLbx (4.4 vs. 6.6 ng/ml; p<.001) in comparison to highTAC/mycophenolate. Histological graft injury quantified by the rejection activity index and hepatitis activity index (Ishak), as well as fibrosis were not significantly different between the EVR/lowTAC and highTAC/mycophenolate groups. Likewise, subclinical TCMR, histological criteria justifying immunosuppression minimization, and steatosis had equal prevalence in both regimens. Immunosuppression was adjusted according to the svLbx findings. Immunosuppression regimens had similarly low rates of rejection after immunosuppression reduction, when relevant graft injury was absent in the biopsy.

Discussion

In conclusion, EVR/lowTAC seems to control alloreactivity and histological graft injury as sufficiently as highTAC/mycophenolate within the first 3-4 years after OLT.

Safety and efficacy of everolimus initiation from the first month after liver transplantation: A systematic review and meta-analysis

INTRODUCTION

Everolimus, a selective inhibitor of mamalian target of rapamycin (mTORi), is considered to be an alternative immunosuppressive regimen in the liver transplantation (LT) setting. However, most of the transplant centers avoid its early use (i.e., during the first month) after LT mainly due to safety issues.

METHODS

We searched for all articles published between 01/2010 and 7/2022 to evaluate the effectiveness and safety of initial/early administration of everolimus after LT.

RESULTS

Seven studies (three randomized controlled trials and four prospective cohort studies) were included: initial/early everolimus-including therapy (group 1) was used in 512 (51%) and calcineurin inhibitor (CNI) based therapy (group 2) in 494 (49%) patients. No significant difference was found between group 1 and group 2 patients regarding the rates of biopsy-proven acute rejection episodes (Odds Ratio [OR]: 1.27, 95% CI: .67-2.41, p = .465) and hepatic artery thrombosis (OR: .43, 95% CI: .09-2.02, p = .289). Everolimus was associated with higher rates of dyslipidemia (14.2% vs. 6.8%, p = .005) and incisional hernia (29.2% vs. 10.1%, p < .001). Finally, no difference was found between the two groups regarding recurrence of hepatocellular carcinoma (Risk Rates [RR]: 1.22 95%CI: .66-2.29, p = .524) and mortality (RR: .85 95%CI: .48-1.50, p = .570).

CONCLUSION

Use of initial/early everolimus seems to be effective with a satisfactory safety profile, making its administration a reasonable therapeutic option in the LT setting.

Experience with the mTOR Inhibitor Everolimus in Pediatric Liver Graft Recipients

INTRODUCTION

Immunosuppression after pediatric liver transplantation remains a major challenge. MTOR inhibitors provide a promising therapeutic approach in combination with reduced CNI after transplantation. However, there are still few data regarding their use in children.

PATIENTS

We analyzed 37 patients with a median age of 10 years, who received Everolimus for one or more of the following indications: I = chronic graft dysfunction (n = 22); II = progressive renal impairment (n = 5); III = non-tolerable side effects with previous immunosuppressive medication (n = 6); and IV = malignancies (n = 10). The median follow-up time was 36 months.

RESULTS

Patient survival was 97%, and graft survival 84%, respectively. Stabilization of graft function was observed in 59% in subgroup 1, with 18.2% ultimately requiring retransplantation. No patient in subgroup IV developed recurrence of his primary tumor or PTLD by the endpoint of the study. Side effects were observed in 67.5% of the study patients, with infections being the most frequent (n = 20; 54.1%). There were no relevant effects on growth and development.

CONCLUSION

Everolimus seems to be a treatment option in selected pediatric liver graft recipients for whom other regimens are not suitable. Overall, the efficacy was good and the side effect profile appeared to be acceptable.

Liver Transplantation for the Nonhepatologist

Liver transplantation (LT) is a life-saving and evidence-based intervention for patients with acute liver failure and chronic end-stage liver disease. Significant progress has been made in advancing pre-LT management, transplant techniques, post-LT long-term care, and immunosuppression regimes. However, as rates of DC continue to increase, causes of liver disease and indications for LT continue to be investigated to ensure equity and further improve liver allocation models, waitlist outcomes, and post-LT outcomes for all patient populations.

Where Are We Now with Liver Transplantation in Neuroendocrine Neoplasms? The Place of Liver Transplantation for Grades 1 and 2 Well-Differentiated Unresectable Liver Metastatic Neuroendocrine Tumours

PURPOSE OF REVIEW

This review outlines the role of liver transplantation in selected patients with unresectable neuroendocrine tumour liver metastases. It discusses the international consensus on eligibility criteria and outlines the efforts taking place in the UK and Ireland to develop effective national liver transplant programmes for neuroendocrine tumour patients.

RECENT FINDINGS

In the early history of liver transplantation, indications included cancer metastases to the liver as well as primaries of liver origin. Often, liver transplantation was a salvage procedure. The early results were disappointing, including in patients with neuroendocrine tumours. These data discouraged the widespread adoption of liver transplantation for neuroendocrine tumour liver metastases (NET LM). A few centres persisted in performing liver transplantation for patients with NET LM and in determining parameters predictive of good outcomes. Their work has provided evidence for benefit of liver transplantation in a selected group of patients with NET LM. Liver transplantation for NET LM is now accepted as a valid indication by many professional bodies, including the European Neuroendocrine Tumour Society (ENETS) and the United Network for Organ Sharing (UNOS). It is nevertheless rarely utilised. The UK and the Republic of Ireland are commencing a pilot programme of liver transplantation in selected patients. This programme will help develop the expertise and infrastructure to make liver transplantation for NET LM a routine procedure.

Impact of very early introduction of everolimus on liver regeneration after partial liver transplantation in rats

BACKGROUND/PURPOSE

This experimental study in rats aimed to investigate the impact of very early introduction (within 3 h) of everolimus (EVR) + reduced-tacrolimus (TAC) after partial liver transplantation (LT) on liver regeneration, rejection, and survival.

METHODS

Based on appropriate dose of EVR + reduced-TAC in 70% hepatectomy (Experiment 1), allogeneic 30% partial LT (Experiment 2) and whole LT (Experiment 3) were performed.

RESULTS

After partial LT in EVR + reduced-TAC therapy, restoration of liver graft weight (to that of the whole liver) was delayed compared with standard dose TAC monotherapy (standard-TAC) on day 3 (59.3% vs. 72.9%; p < .001) and 14 (88.1% vs. 95.5%; p = .01). Survival was 75%, which was not as high as the value of 100% observed for standard-TAC, because neither infection nor rejection could be prevented. By contrast, survival after whole LT was 100% as neither infection nor rejection occurred.

CONCLUSIONS

The very early introduction of EVR + reduced-TAC after partial LT delayed liver regeneration, and made it difficult to manage the dose required to suppress both infection and rejection. On the other hand, EVR + reduced-TAC could be introduced safely very early after whole LT.

Long-Term Effects of Everolimus-Facilitated Tacrolimus Reduction in Living-Donor Liver Transplant Recipients with Hepatocellular Carcinoma

BACKGROUND The study objective was to evaluate the effect of everolimus (EVR) in combination with reduced tacrolimus (rTAC) compared with a standard TAC (sTAC) regimen on hepatocellular carcinoma (HCC) recurrence in de novo living-donor liver transplantation recipients (LDLTRs) with primary HCC at liver transplantation through 5 years after transplantation. MATERIAL AND METHODS In this multicenter, non-interventional study, LDLTRs with primary HCC, who were previously randomized to either everolimus plus reduced tacrolimus (EVR+rTAC) or standard tacrolimus (sTAC), and who completed the 2-year core H2307 study, were followed up. Data were collected retrospectively (end of core to the start of follow-up study), and prospectively (during the 3-year follow-up study). RESULTS Of 117 LDLTRs with HCC at LT in the core H2307 study (EVR+rTAC, N=56; sTAC, N=61), 86 patients (EVR+rTAC, N=41; sTAC, N=45) entered the follow-up study. Overall HCC recurrence was lower but statistically non-significant in the EVR+rTAC group (3.6% vs 11.5% in sTAC; P=0.136) at 5 years after LT. There was no graft loss or chronic rejection. Acute rejection and death were comparable between treatment groups. Higher mean estimated glomerular filtration rate in the EVR+rTAC group (76.8 vs 65.8 mL/min/1.73 m² in sTAC) was maintained up to 5 years. Reported adverse events were numerically lower in the EVR+rTAC group (41.0% vs 53.5% sTAC) but not statistically significant. CONCLUSIONS Although statistically not significant, early EVR initiation reduced HCC recurrence, with comparable efficacy and safety, and better long-term renal function, than that of sTAC treatment.

Population pharmacokinetics of everolimus in adult liver transplant patients: Comparison to tacrolimus disposition and extrapolation to pediatrics

Everolimus has recently been used to prevent graft rejection in liver transplantation and reduces the incidence of kidney dysfunction caused by calcineurin inhibitors. In this study, a population pharmacokinetic analysis was conducted to improve the individualization of everolimus therapy. Japanese post-liver transplant patients whose blood everolimus concentrations were measured between March 2018 and December 2020 were included in this study. A nonlinear mixed-effect modeling program was used to explore covariates that affect everolimus pharmacokinetics. Individual everolimus pharmacokinetic parameters estimated by the post-hoc Bayesian analysis using the final model were compared with the tacrolimus dose per trough concentration (D/C) ratio in each patient. The final model was extrapolated to pediatric liver transplant patients for external evaluation. A total of 937 concentrations from 87 adult patients were used in the model-building process. Everolimus clearance was significantly affected by the estimated glomerular filtration rate, concomitant use of fluconazole, sex, as well as total daily dose of everolimus (TDM effect). The estimated individual apparent clearance of everolimus by the post-hoc Bayesian analysis was moderately correlated with the D/C ratio of tacrolimus in each patient (R²  = 0.330, p < 0.0001). The estimation accuracy in pediatric patients was considerably high, except for one infant out of 13 patients. In conclusion, population pharmacokinetic analysis clarified several significant covariates for everolimus pharmacokinetics in liver transplant patients. Everolimus pharmacokinetics moderately correlated with tacrolimus pharmacokinetics and could be extrapolated from adult to pediatric patients by body size correction, except for infants.

Immunosuppressive Drugs in Liver Transplant: An Insight

Liver transplantation (LT) is the standard of care for end-stage liver failure and hepatocellular carcinoma. Over the years, immunosuppression regimens have improved, resulting in enhanced graft and patient survival. At present, the side effects of immunosuppressive agents are a significant threat to post-LT quality of life and long-term outcome. The role of personalized immunosuppression is to reach a delicate balance between optimal immunosuppression and minimal side effects. Today, immunosuppression in LT is more of an art than a science. There are no validated markers for overimmunosuppression and underimmunosuppression, only a few drugs have therapeutic drug monitoring and immunosuppression regimens vary from center to center. The immunosuppressive agents are broadly classified into biological agents and pharmacological agents. Most regimens use multiple agents with different modes of action to reduce the dosage and minimize the toxicities. The calcineurin inhibitor (CNI)-related toxicities are reduced by antibody induction or using mTOR inhibitor/antimetabolites as CNI sparing or CNI minimization strategies. Post-liver transplant immunosuppression has an intensive phase in the first three months when alloreactivity is high, followed by a maintenance phase when immunosuppression minimization protocols are implemented. Over time some patients achieve "tolerance," defined as the successful stopping of immunosuppression with good graft function and no indication of rejection. Cell-based therapy using immune cells with tolerogenic potential is the future and may permit complete withdrawal of immunosuppressive agents.

Five-year outcomes in liver transplant patients receiving everolimus with or without a calcineurin inhibitor: Results from the CERTITUDE study

BACKGROUND AND AIMS

To report 5-year outcomes of the CERTITUDE study.

METHODS

An observational study in patients with liver transplantation (LTx) compared the long-term impact of immunosuppression (with/without a calcineurin inhibitor) on renal function, cancers, major cardiovascular events (MACEs) and other safety parameters. All patients completing the 6-month SIMCER study were recruited and analysed according to treatment received at randomization and actual treatment received during the follow-up.

RESULTS

Of the 143 enrolled patients, 119 completed the 5-year follow-up (everolimus [EVR], n = 55; tacrolimus [TAC], n = 64). The mean absolute change in estimated glomerular filtration rate was not statistically different between both groups (TAC, -15.53 ml/min/1.73 m² and EVR, -14.56 ml/min/1.73 m² ). In the treatment subgroups based on actual treatment received, renal function was preserved better in the EVR subgroup compared with other subgroups (p = .051). Treated biopsy-proven acute rejection was higher in the EVR group (15.4% vs. 6.4%); however, the majority of events were mild in severity. MACE occurred in 9.2% vs. 14.1% of patients in the EVR and TAC groups respectively (p = .370). De novo cancer was reported in 14 and 5 patients in EVR and TAC groups respectively. Hepatocellular carcinoma (HCC) recurrence was observed in the TAC group alone (n = 4). Adverse events and treatment discontinuation owing to an adverse event were higher in the EVR group.

CONCLUSIONS

The CERTITUDE study demonstrated that EVR- and TAC-based regimens have comparable efficacy, safety and tolerability up to 5 years post-LTx.

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.

[Update: Immunosuppression in organ transplantation]

Immunosuppression is an essential prerequisite for successful transplantation. In order to reduce the sometimes-considerable side effects, combination therapies with different agents are used. This article aims to provide an up-to-date overview of immunosuppression after liver and kidney transplantation.

Prädiktoren für erfolgreiche Lebertransplantationen und Risikofaktoren

Die Lebertransplantation ist die einzige kurative Therapieoption einer chronischen Leberinsuffizienz im Endstadium. Daneben stellen onkologische Lebererkrankungen wie das HCC eine weitere Indikation für die Lebertransplantation dar, ebenso wie das akute Leberversagen.

Seit der ersten erfolgreichen Lebertransplantation durch Professor Thomas E. Starzl im Jahr 1967 haben sich nicht nur die chirurgischen, immunologischen und anästhesiologischen Techniken und Möglichkeiten geändert, sondern auch die Indikationen und das Patientengut. Hinzu kommt, dass die Empfänger ein zunehmendes Lebensalter und damit einhergehend mehr Begleiterkrankungen aufweisen.

Die Zahl an Lebertransplantationen ist weltweit weiter ansteigend. Es benötigen aber mehr Menschen eine Lebertransplantation, als Organe zur Verfügung stehen. Dies liegt am zunehmenden Bedarf an Spenderorganen bei gleichzeitig weiter rückläufiger Zahl postmortaler Organspenden.

Diese Diskrepanz zwischen Spenderorganen und Empfängern kann nur zu einem kleinen Teil durch Split-Lebertransplantationen oder die Leberlebendspende kompensiert werden.

Um den Spenderpool zu erweitern, werden zunehmend auch marginale Organe, die nur die erweiterten Spenderkriterien („extended donor criteria [EDC]“) erfüllen, allokiert. In manchen Ländern zählen hierzu auch die sogenannten DCD-Organe (DCD: „donation after cardiac death“), d. h. Organe, die erst nach dem kardiozirkulatorischen Tod des Spenders entnommen werden.

Es ist bekannt, dass marginale Spenderorgane mit einem erhöhten Risiko für ein schlechteres Transplantat- und Patientenüberleben nach Lebertransplantation einhergehen.

Um die Qualität marginaler Spenderorgane zu verbessern, hat sich eine rasante Entwicklung der Techniken der Organkonservierung über die letzten Jahre gezeigt. Mit der maschinellen Organperfusion besteht beispielsweise die Möglichkeit, die Organqualität deutlich zu verbessern. Insgesamt haben sich die Risikokonstellationen von Spenderorgan und Transplantatempfänger deutlich geändert.

Aus diesem Grunde ist es von großer Bedeutung, spezifische Prädiktoren für eine erfolgreiche Lebertransplantation sowie die entsprechenden Risikofaktoren für einen schlechten postoperativen Verlauf zu kennen, um das bestmögliche Transplantat- und Patientenüberleben nach Lebertransplantation zu ermöglichen.

Diese Einflussfaktoren, inklusive möglicher Risiko-Scores, sollen hier ebenso wie die neuen technischen Möglichkeiten in der Lebertransplantation beleuchtet werden.

Everolimus versus mycophenolate mofetil in liver transplantation: every improvement in renal function matters

The current edition of the journal features a Spanish, nationwide, multi-institutional study by Gomez Bravo MA et al. exploring the advantages of everolimus (EVR)-facilitated tacrolimus (TAC) minimization versus TAC in combination with mycophenolate mofetil (MMF) after liver transplantation (LT).

Early Everolimus-Facilitated Reduced Tacrolimus in Liver Transplantation: Results From the Randomized HEPHAISTOS Trial

Everolimus-facilitated reduced-exposure tacrolimus (EVR + rTAC) at 30 days after liver transplantation (LT) has shown advantages in renal preservation. This study evaluated the effects of early initiation of EVR + rTAC in de novo LT recipients (LTRs). In HEPHAISTOS (NCT01551212, EudraCT 2011-003118-17), a 12-month, multicenter, controlled study, LTRs were randomly assigned at 7 to 21 days after LT to receive EVR + rTAC or standard-exposure tacrolimus (sTAC) with steroids. The primary objective was to demonstrate superior renal function (assessed by estimated glomerular filtration rate [eGFR]) with EVR + rTAC versus sTAC at month 12 in the full analysis set (FAS). Other assessments at month 12 included the evaluation of renal function in compliance set and on-treatment (OT) patients, efficacy (composite endpoint of graft loss, death, or treated biopsy-proven acute rejection [tBPAR] and individual components) in FAS, and safety. In total, 333 patients (EVR + rTAC, 169; sTAC, 164) were included in the FAS. A high proportion of patients was nonadherent in maintaining tacrolimus trough levels (EVR + rTAC, 36.1%; sTAC, 34.7%). At month 12, the adjusted least square mean eGFR was numerically higher with EVR + rTAC versus sTAC (76.2 versus 72.1 mL/minute/1.73 m2 , difference: 4.1 mL/minute/1.73 m2 ; P = 0.097). A significant difference of 8.3 mL/minute/1.73 m2 (P = 0.03) favoring EVR + rTAC was noted in the compliance set. Incidence of composite efficacy endpoint (7.7% versus 7.9%) and tBPAR (7.1% versus 5.5%) at month 12 as well as incidence of treatment-emergent adverse events (AEs) and serious AEs were comparable between groups. A lower proportion of patients discontinued EVR + rTAC than sTAC treatment (27.2% versus 34.1%). Early use of everolimus in combination with rTAC showed comparable efficacy, safety, and well-preserved renal function versus sTAC therapy at month 12. Of note, renal function was significantly enhanced in the compliance set.

Safety of Tacrolimus Monotherapy within 12 Months after Liver Transplantation in the Era of Reduced Tacrolimus and Mycophenolate Mofetil: National Registry Study

Tacrolimus monotherapy is accepted as a feasible option during early post-liver transplantation as per current international consensus guidelines. However, its effects in the recent era of reduced tacrolimus (TAC) and mycophenolate mofetil (MMF) remain unclear. Liver recipients who either received TAC monotherapy from the treatment onset or switched from TAC/MMF to TAC-mono within 12 months (TAC-mono group; n = 991) were chronologically matched to patients who continued to receive TAC/MMF (TAC/MMF group; n = 991) at the corresponding time points on time-conditional propensity scores. Outcomes within 12 months after matched time points were compared. Biopsy-proven rejection (TAC/MMF: 3.5% vs. TAC-mono: 2.6%; p = 0.381) and graft failure (0.2% vs. 0.7%; p = 0.082) were similar in both groups. However, the decline in eGFR was 3.1 mL/min/1.73 m2 (95% CI: 0.8-5.3) greater at six months (p = 0.008) and 2.4 mL/min/1.73 m2 (95% CI: -0.05-4.9) greater at 12 months (p = 0.048) after the matched time points in TAC-mono group than that in TAC/MMF group. TAC trough levels were also higher in the TAC-mono group throughout the study period. TAC-mono within 12 months after liver transplantation is immunologically safe. However, it can increase the required TAC dose and the decline in renal function than that in TAC/MMF combination therapy.

[Kidney failure after liver transplantation]

One third of cirrhotic patients present impaired kidney function. It has multifactorial causes and has a harmful effect on patients' morbi-mortality before and after liver transplant. Kidney function does not improve in all patients after liver transplantation and liver-transplant recipients are at high risk of developing chronic kidney disease. Causes for renal dysfunction can be divided in three groups: preoperative, peroperative and postoperative factors. To date, there is no consensus for the modality of evaluation the risk for chronic kidney disease after liver transplantation, and for its prevention. In the present review, we describe the outcome of kidney function after liver transplantation, and the prognostic factors of chronic kidney disease to determine a risk stratification for each patient. Furthermore, we discuss therapeutic options to prevent kidney dysfunction in this setting, and highlight the indications of combined liver-kidney transplantation.

Prognostic Impact of Early Recovering Acute Kidney Injury Following Liver Transplantation: A Multicenter Retrospective Study

BACKGROUND

Acute kidney injury (AKI) is a common complication after liver transplantation (LT), but the specific impact of rapidly resolving AKI is not elucidated. This study investigates the factors associated with early recovery from AKI and its association with post-LT outcomes.

METHODS

Retrospective analysis of 441 liver transplant recipients with end-stage liver disease without pretransplant renal impairment. AKI was defined according to Kidney Disease Improving Global Outcomes criteria and early renal recovery by its disappearance within 7 d post-LT.

RESULTS

One hundred forty-six patients (32%) developed a post-LT AKI, of whom 99 (69%) recovered early and 45 (31%) did not. Factors associated with early recovery were Kidney Disease Improving Global Outcomes stage 1 (odds ratio [OR],14.11; 95% confidence interval [CI], 5.59-40.22; P < 0.0001), minimum prothrombin time >50 % (OR, 4.50; 95% CI, 1.67-13.46; P = 0.003) and aspartate aminotransferase peak value <1000 U/L (OR, 4.07; 95% CI, 1.64-10.75; P = 0.002) within 48 h post-LT. Patients with early recovery had a renal prognosis similar to that of patients without AKI with no difference in estimated glomerular filtration rate between day 7 and 1 y. Their relative risk of developing chronic kidney disease was 0.88 (95% CI, 0.55-1.41; P = 0.6) with survival identical to patients without AKI and better than patients without early recovery (P < 0.0001).

CONCLUSIONS

Most patients with post-LT AKI recover early and have a similar renal prognosis and survival to those without post-LT AKI. Factors associated with early renal recovery are related to the stage of AKI, the extent of liver injury, and the early graft function. Patients at risk of not recovering may benefit the most from perioperative protective strategies, particularly those aimed at minimizing the adverse effects of calcineurin inhibitors.

An Essential Guide for Managing Post-Liver Transplant Patients: What Primary Care Physicians Should Know

With long-term survival after liver transplantation becoming the rule, care for medical problems arising over time in liver-transplanted patients gained increasing importance. The most common causes of death occurring more than 1 year after liver transplantation are unrelated to liver diseases and facilitated by immunosuppressive treatments; examples are malignancies, renal failure, and cardiovascular, metabolic, and infectious diseases. Recipients receive life-long follow-up care at transplant centers, however, the increasing number of liver-transplanted patients is saturating the health care supply that transplant centers have to offer. Primary care physicians are increasingly exposed to liver-transplanted patients, even in the early periods after transplant, and an understanding of the most common risks and complications faced by these patients would enhance their care. This article reviews the long-term care of liver transplant recipients, emphasizing the key internal medicine-related issues that should be known by primary care physicians. A specific section is devoted to implementing strategies to involve these physicians in the long-term follow-up of liver-transplanted patients in close collaboration with transplant hepatologists.

Donor-derived cell-free DNA levels predict graft injury in liver transplant recipients

Donor-derived cell-free DNA (dd-cfDNA) has been evaluated as a rejection marker in organ transplantation. This study sought to assess the utility of dd-cfDNA to diagnose graft injury in liver transplant recipients (LTR) and as a predictive biomarker prior to different causes of graft dysfunction. Plasma from single and multicenter LTR cohorts was analyzed for dd-cfDNA. Phenotypes of treated biopsy-proven acute rejection (AR, N = 57), normal function (TX, N = 94), and acute dysfunction no rejection (ADNR; N = 68) were divided into training and test sets. In the training set, dd-cfDNA was significantly different between AR versus TX (AUC 0.95, 5.3% cutoff) and AR versus ADNR (AUC 0.71, 20.4% cutoff). Using these cutoffs in the test set, the accuracy and NPV were 87% and 100% (AR vs. TX) and 66.7% and 87.8% (AR vs. ADNR). Blood samples collected serially from LTR demonstrated incremental elevations in dd-cfDNA prior to the onset of graft dysfunction (AR > ADNR), but not in TX. Dd-cfDNA also decreased following treatment of rejection. In conclusion, the serial elevation of dd-cfDNA identifies pre-clinical graft injury in the context of normal liver function tests and is greatest in rejection. This biomarker may help detect early signs of graft injury and rejection to inform LTR management strategies.

Outcome and safety of a surveillance biopsy guided personalized immunosuppression program after liver transplantation

Graft survival beyond year 1 has not changed after orthotopic liver transplantation (OLT) over the last decades. Likewise, OLT causes comorbidities such as infection, renal impairment and cancer. We evaluated our single-center real-world individualized immunosuppression program after OLT, based on 211 baseline surveillance biopsies (svLbx) without any procedural complications. Patients were classified as low, intermediate and high rejection risk based on graft injury in svLbx and anti-HLA donor-specific antibodies. While 32% of patients had minimal histological inflammation, 57% showed histological inflammation and 23% advanced fibrosis (>F2), which was not predicted by lab parameters. IS was modified in 79% of patients after svLbx. After immunosuppression reduction in 69 patients, only 5 patients showed ALT elevations and three of these patients had a biopsy-proven acute rejection, two of them related to lethal comorbidities. The rate of liver enzyme elevation including rejection was not significantly increased compared to a svLbx control cohort prior to the initiation of our structured program. Immunosuppression reduction led to significantly better kidney function compared to this control cohort. In conclusion, a biopsy guided personalized immunosuppression protocol after OLT can identify patients requiring lower immunosuppression or patients with graft injury in which IS should not be further reduced.

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.

Predictive Factors for Humoral Response After 2-dose SARS-CoV-2 Vaccine in Solid Organ Transplant Patients

Background

A weak immunogenicity has been reported in solid organ transplant (SOT) recipients after 2 doses of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine. The aim of this retrospective study was to identify the predictive factors for humoral response in SOT patients.

Methods

Three hundred and ninety-three SOT patients from our center with at least 4 wk of follow-up after 2 doses of mRNA-based vaccine were included in this study. Anti-SARS-Cov-2 spike protein antibodies were assessed before and after vaccination.

Results

Anti-SARS-CoV-2 antibodies were detected in 34% of the patients: 33.7% of kidney transplant patients, 47.7% of liver transplant patients, and 14.3% of thoracic transplant patients (P = 0.005). Independent predictive factors for humoral response after vaccination were male gender, a longer period between transplantation and vaccination, liver transplant recipients, a higher lymphocyte count at baseline, a higher estimated glomerular filtration rate and receiving the tacrolimus + everolimus ± steroids combination. Conversely, the nondevelopment of anti-SARS-CoV-2 antibodies after vaccination was associated with younger patients, thoracic organ recipients, induction therapy recipients, and tacrolimus + mycophenolic acid ± steroids recipients.

Conclusions

The immunosuppressive regimen is a modifiable predictive factor for humoral response to SARS-CoV-2 vaccine.

Post-liver transplantation chronic kidney disease is associated with increased cardiovascular disease risk and poor survival

Chronic kidney disease (CKD) is common following liver transplantation (LT). We aimed to investigate the frequency, risk factors, and impact of CKD on cardiovascular disease (CVD), graft, and patient survival. We analyzed 752 patients who received LT at the University of Alberta. Development of CKD was defined as eGFR <60 ml/min for greater than 3 months, intrinsic renal disease or presence of end-stage renal disease requiring renal replacement therapy. 240 patients were female (32%), and mean age at LT was 53 ± 11 years. CKD was diagnosed in 448 (60%) patients. On multivariable analysis, age (OR 1.3; P = 0.01), female sex (OR 3.3; P < 0.001), baseline eGFR (OR 0.83; P < 0.001), MELD (OR 1.03; P = 0.01), de novo metabolic syndrome (OR 2.3; P = 0.001), and acute kidney injury (OR 3.5; P < 0.001) were associated with CKD. A higher tacrolimus concentration to dose ratio was protective for CKD (OR 0.69; P < 0.001). CKD was associated with post-transplant CVD (26% vs. 16% P < 0.001), reduced graft (HR 1.4; P = 0.02), and patient survival (HR 1.3; P = 0.03). CKD is a frequent complication following LT and is associated with an increased risk of CVD and reduced graft and patient survival.

Strategies to Improve Immune Suppression Post-Liver Transplantation: A Review

Since the first liver transplantation operation (LT) in 1967 by Thomas Starzl, efforts to increase survival and prevent rejection have taken place. The development of calcineurin inhibitors (CNIs) in the 1980s led to a surge in survival post-transplantation, and since then, strategies to prevent graft loss and preserve long-term graft function have been prioritized. Allograft rejection is mediated by the host immune response to donor antigens. Prevention of rejection can be achieved through either immunosuppression or induction of tolerance. This leads to a clinical dilemma, as the choice of an immunosuppressive agent is not an easy task, with considerable patient and graft-related morbidities. On the other hand, the induction of graft tolerance remains a challenge. Despite the fact that the liver exhibits less rejection than any other transplanted organs, spontaneous graft tolerance is rare. Most immunosuppressive medications have been incriminated in renal, cardiovascular, and neurological complications, relapse of viral hepatitis, and recurrence of HCC and other cancers. Efforts to minimize immunosuppression are directed toward decreasing medication side effects, increasing cost effectiveness, and decreasing economic burden without increasing the risk of rejection. In this article, we will discuss recent advances in strategies for improving immunosuppression following liver transplantation.

Post-Liver Transplant Acute Kidney Injury

Acute kidney injury (AKI) is a common condition following liver transplantation (LT). It negatively impacts patient outcomes by increasing the chances of developing chronic kidney disease and reducing graft and patient survival rates. Multiple definitions of AKI have been proposed and used throughout the years, with the International Club of Ascites definition being the most widely now used for patients with cirrhosis. Multiple factors are associated with the development of post-LT AKI and can be categorized into pre-LT comorbidities, donor and recipient characteristics, operative factors, and post-LT factors. Many of these factors can be optimized in an attempt to minimize the risk of AKI occurring and to improve renal function if AKI is already present. A special consideration during the post-LT phase is needed for immunosuppression as certain immunosuppressive medications can be nephrotoxic. The calcineurin inhibitor tacrolimus (TAC) is the mainstay of immunosuppression but can result in AKI. Several strategies including use of the monoclonoal antibody basilixamab to allow for delayed initiation of tacrolimus therapy and minimization through combination and minimization or elimination of TAC through combination with mycophenolate mofetil or mammalian target of rapamycin inhibitors have been implemented to reverse and avoid AKI in the post-LT setting. Renal replacement therapy may ultimately be required to support patients until recovery of AKI after LT. Overall, by improving renal function in post-LT patients with AKI, outcomes can be improved.