Randomized controlled trial of tacrolimus versus microemulsified cyclosporin (TMC) in liver transplantation: poststudy surveillance to 3 years

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

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.

Population Pharmacokinetic Modeling Combined With Machine Learning Approach Improved Tacrolimus Trough Concentration Prediction in Chinese Adult Liver Transplant Recipients

This study aimed to develop and evaluate a population pharmacokinetic (PPK) combined machine learning approach to predict tacrolimus trough concentrations for Chinese adult liver transplant recipients in the early posttransplant period. Tacrolimus trough concentrations were retrospectively collected from routine monitoring records of liver transplant recipients and divided into the training data set (1287 concentrations in 145 recipients) and the test data set (296 concentrations in 36 recipients). A PPK model was first established using NONMEM. Then a machine learning model of Xgboost was adapted to fit the estimated individual pharmacokinetic parameters obtained from the PPK model with Bayesian forecasting. The performance of the final PPK model and Xgboost model was compared in the test data set. In the final PPK model, tacrolimus daily dose, postoperative days, hematocrit, aspartate aminotransferase, and concomitant voriconazole, were identified to significantly influence the clearance. The postoperative days along with hematocrit significantly influence the volume of distribution. In the Xgboost model, the first 5 predictors for predicting the clearance were concomitant with voriconazole, sex, single nucleotide polymorphisms of CYP3A4*1G and CYP3A5*3 in recipients, and tacrolimus daily dose, for the volume of distribution were postoperative days, age, weight, total bilirubin and graft : recipient weight ratio. In the test data set, the Xgboost model showed the minimum median prediction error of tacrolimus concentrations, less than the PPK model with or without Bayesian forecasting. In conclusion, a PPK combined machine learning approach could improve the prediction of tacrolimus concentrations for Chinese adult liver transplant recipients in the early posttransplant period.

Protective effect of silymarin on tacrolimus-induced kidney and liver toxicity

BACKGROUND

Tacrolimus (FK506) is an immunosuppressive agent and has toxic side effects such as nephrotoxicity, hepatotoxicity, and neurotoxicity. In our study, we aimed to investigate the protective effect of silymarin on renal and hepatic toxicity considered to be tacrolimus related.

METHODS

In this 6-week experimental study, 46 eight-week-old healthy male rats were used. The groups comprised the Control (healthy rats, n = 6), Tac (tacrolimus 1 mg/kg, n = 8), silymarin 100 mg/kg (SLI 100 mg/kg n = 8), Tac + SLI 100 (tacrolimus 1 mg/kg + SLI 100 n = 8), SLI 200 (SLI 200 mg/kg n = 8), and Tac + SLI 200 (tacrolimus 1 mg/kg + SLI 200 mg/kg n = 8). After 6 weeks, all rats were sacrificed, and the tissue follow-up procedure was performed for kidney and liver tissues, histopathology, and in situ TUNEL analysis. Blood samples were analyzed for the total antioxidant capacity (TAC), total oxidant capacity (TOC), alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), albumin, total bilirubin, creatine.

RESULTS

Histopathological findings of kidney and liver tissue of rats were determined to increase statistically in Tac group compared to SLI 1 00 and SLI 200 groups (P < 0.05). In addition, the Tac + SLI 100 and Tac + SLI 200 groups were found to be statistically similar to the Control group (P > 0.05). The in situ TUNEL method showed that the tacrolimus increased apoptosis while the silymarin decreased it. TOC levels increased statistically in Tac groups compared to silymarin-treated groups (P < 0.05). Although the TAC level was not statistically significant among the experimental groups (P > 0.05), the lowest was measured in the Tac group. The ALT, AST, GGT, total bilirubin, and creatine values were higher in the Tac group than in the silymarin groups (P < 0.05). There was no statistically significant difference between the groups with regard to the albumin level (P > 0.05).

CONCLUSION

In our study, we determined that tacrolimus caused damage to kidney and liver tissue. Histopathological, biochemical and apoptotic findings show that silymarin has a protective effect against nephrotoxicity and hepatotoxicity caused by tacrolimus.

Immunosuppressive drugs and associated complications in abdominal organ transplantation

PURPOSE OF REVIEW

Intensive care management of patients who have undergone organ transplantation of liver, small bowel, pancreas, and/or kidney requires a basic knowledge of immunosuppression principles and the management of immunosuppressive medications. This review highlights the core principles of immunosuppression management in abdominal organ transplantation with a focus on complications arising from immunosuppressive drugs, both in the immediate postoperative period and in long-term usage.

RECENT FINDINGS

The general principles of management of immunosuppression in the abdominal organ transplant population have remained largely unchanged. Improvements in drug monitoring coupled with improvements in knowledge of pathways involved in allograft rejection have further refined immunosuppressive therapy. Infectious and central nervous system complications remain prevalent and are common complications of immunosuppressive drug therapy.

SUMMARY

For the intensive care professional who cares for abdominal organ transplant recipients, a foundational knowledge of the core principles of immunosuppression management is essential. In addition, an understanding of the common immunosuppressive drug regimens and the complications associated with these regimens is required for optimal management, risk assessment, and outcomes.

Long-Term Tacrolimus Blood Trough Level and Patient Survival in Adult Liver Transplantation

Tacrolimus is the most widely used immunosuppressant in liver transplant (LT) patients. However, the ideal long-term target level for these patients is unknown. This retrospective study aimed to investigate the impact of tacrolimus blood concentration five years after LT on long-term patient survival outcomes in adult LT recipients. Patients who underwent LT between January 2004 and July 2014 at a tertiary medical center were included in this study (n = 189). The mean tacrolimus blood concentrations of each patient during the fifth year after LT were recorded and the overall survival rate was determined. A multivariate analysis of factors associated with long-term survival was conducted using a Cox’s model. The median follow-up period was 9.63 years, and 144 patients (76.2%) underwent live donor LT. Sixteen patients died within 5 years of LT. In the Cox’s model, patients with a mean tacrolimus blood trough level of 4.6–10.2 ng/mL had significantly better long-term survival than those with a mean tacrolimus blood trough level outside this range (estimated hazard ratio = 4.76; 95% confidence interval: 1.34–16.9, p = 0.016). Therefore, a tacrolimus level no lower than 4.6 ng/mL would be recommended in adult LT patients.

Real-World Administration of Once-Daily MeltDose® Prolonged-Release Tacrolimus (LCPT) Allows for Dose Reduction of Tacrolimus and Stabilizes Graft Function Following Liver Transplantation

The calcineurin inhibitor tacrolimus is included in most immunosuppressive protocols after liver transplantation. This retrospective, observational 24-month study investigated the tolerability of once-daily MeltDose^® prolonged-release tacrolimus (LCPT) after switching from twice-daily immediate-release tacrolimus (IR-Tac) in a real-world cohort of 150 patients with previous liver transplantation. No graft rejection or new safety signals were observed. Only 7.3% of patients discontinued LCPT due to side effects. In the overall patient population, median liver transaminases, total cholesterol, triglycerides, glucose, and HbA_1c remained constant after switching to LCPT. Total cholesterol significantly decreased (p ≤ 0.002) in patients with initially elevated levels (>200 mg/dL). A total of 71.8% of 96 patients maintained a glomerular filtration rate > 60 mL/min/1.73 m² throughout the study, while 44.7% of patients were classified as fast metabolizers and 55.3% as slow metabolizers. Median daily tacrolimus dose could be reduced by 50% in fast metabolizers and by 30% in slow metabolizers, while trough levels were maintained in the target range (4–6 ng/mL). In conclusion, our observational study confirmed previous evidence of good overall tolerability and a favorable outcome for the patients after switching from IR-Tac to LCPT after liver transplantation.

Effects of tacrolimus on the TGF‑β1/SMAD signaling pathway in paraquat‑exposed rat alveolar type II epithelial cells

Paraquat is a highly toxic pesticide, which often causes pulmonary interstitial fibrosis after poisoning, and there is no specific antidote. At present, limited studies have reported that tacrolimus, as an immunosuppressant, can inhibit pulmonary fibrosis, but the specific mechanism remains unknown. The aim of the present study was to demonstrate the effect of tacrolimus on the TGF-β1 pathway associated with pulmonary fibrosis in paraquat exposed alveolar type II epithelial cells, and to identify the antipulmonary fibrosis mechanism of tacrolimus The rat alveolar epithelial type II RLE-6TN cell line was exposed to paraquat and treated with or without tacrolimus for 24 h, or with a TGF-β1 receptor type I/II inhibitor (LY2109761) for 1, 4, 8 or 16 h. MTT assays were used to detect the viability of rat alveolar type II epithelial cells under these different treatment conditions, while the concentrations of TGF-β1, SMAD3, SMAD7 and connective tissue growth factor (CTGF) in the cell culture supernatant were determined using ELISAs. Additionally, reverse transcription-quantitative PCR and immunofluorescence were used to analyze the mRNA and protein expression levels of TGF-β1, SMAD3, CTGF and SMAD7. The results demonstrated that the inhibition of the proliferation of RLE-6TN cells exposed to 200 nmol/l paraquat was 26.05±2.99%. The inhibition rate of 10 ng/ml tacrolimus on paraquat-exposed alveolar type II epithelial cells was 18.40±3.49%. The inhibition rate caused by 5 µmol/l LY2109761 was 26.56±4.49%. The expression levels of TGF-β1, SMAD3 and CTGF, as well as their concentrations in the culture supernatant, were significantly downregulated in the tacrolimus group compared with the paraquat group. However, both the concentration and expression levels of SMAD7 were significantly upregulated in the tacrolimus group compared with the paraquat group. In conclusion, tacrolimus can reduce the levels of TGF-β1, SMAD3 and CTGF, increase the level of SMAD7 in TGF-β1 signaling pathway and protect the development of pulmonary fibrosis in paraquat exposed alveolar epithelial cells.

Conversion from Standard-Release Tacrolimus to MeltDose® Tacrolimus (LCPT) Improves Renal Function after Liver Transplantation

Renal impairment is a typical side effect of tacrolimus (Tac) treatment in liver transplant (LT) recipients. One strategy to avoid renal dysfunction is to increase the concentration/dose (C/D) ratio by improving drug bioavailability. LT recipients converted from standard-release Tac to MeltDose^® Tac (LCPT), a novel technological formulation, were able to reduce the required Tac dose due to higher bioavailability. Hence, we hypothesize that such a conversion increases the C/D ratio, resulting in a preservation of renal function. In the intervention group, patients were switched from standard-release Tac to LCPT. Clinical data were collected for 12 months after conversion. Patients maintained on standard-release Tac were enrolled as a control group. Twelve months after conversion to LCPT, median C/D ratio had increased significantly by 50% (p < 0.001), with the first significant increase seen 3 months after conversion (p = 0.008). In contrast, C/D ratio in the control group was unchanged after 12 months (1.75 vs. 1.76; p = 0.847). Estimated glomerular filtration rate (eGFR) had already significantly deteriorated in the control group at 9 months (65.6 vs. 70.6 mL/min/1.73 m² at study onset; p = 0.006). Notably, patients converted to LCPT already had significant recovery of mean eGFR 6 months after conversion (67.5 vs. 65.3 mL/min/1.73 m² at study onset; p = 0.029). In summary, conversion of LT recipients to LCPT increased C/D ratio associated with renal function improvement.

Successful treatment with tacrolimus in TAFRO syndrome: two case reports and literature review

RATIONALE

TAFRO syndrome is a systemic inflammatory disorder characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis, renal dysfunction, and organomegaly. In contrast to that in multicentric Castleman disease, interleukin-6 targeting strategies seem ineffective in some TAFRO syndrome cases; however, the optimal treatment remains unclear. Here, we report 2 cases of TAFRO syndrome, where 1 with cardiomyopathy, successfully treated with tacrolimus. This is the first case report of successful treatment with tacrolimus in TAFRO syndrome.

PATIENT CONCERNS

Both patients (cases 1 and 2) developed fever, anasarca, thrombocytopenia, renal dysfunction, and mild hepatosplenomegaly.

DIAGNOSES

In both patients, lymph node pathology revealed mixed type Castleman disease-like features, and bone marrow showed reticulin myelofibrosis. TAFRO syndrome was diagnosed based on the patients' laboratory, clinical, and pathologic findings. In case 2, we observed a rare complication of cardiomyopathy with no evidence of takotsubo cardiomyopathy or viral myocarditis.

INTERVENTIONS AND OUTCOMES

In case 1, tocilizumab combined with glucocorticoids was ineffective and caused septic shock; additionally, cyclosporine A was discontinued because of hepatotoxicity. However, tacrolimus was effective in resolving TAFRO syndrome without any adverse events. In case 2, tacrolimus completely reversed TAFRO syndrome and was also effective in cardiomyopathy.

LESSONS

This report suggests that tacrolimus is potentially effective and safe as an initial treatment and a glucocorticoid-sparing agent. Our literature review shows that calcineurin inhibitors, including tacrolimus, may be effective in TAFRO syndrome. Since previous studies indicate a role of Th1 inflammation in TAFRO syndrome pathogenesis, tacrolimus may, therefore, be effective in treating TAFRO syndrome.

Care of the Patient with Liver Failure Requiring Transplantation

Patients undergo liver transplantation to address chronic liver failure, acute fulminant liver failure, or primary liver cancer. Depending on acuity, patients with decompensated chronic or acute fulminant liver failure generally require preoperative intensive care unit admission to manage organ dysfunction. Those with chronic liver failure are allocated an organ based on waiting list position determined by their local organ procurement organization (OPO). This position is dependent upon blood type and Model for End- Stage Liver Disease (MELD) score. These patients thus are critically ill and require preoperative ICU monitoring and care. Patients with hepatocellular carcinoma (HCC) who require liver transplantation are given a MELD exception and rarely require preoperative ICU care. The patient’s ability to undergo liver transplant in the setting of HCC is determined by the Milan criteria or the University of California, San Francisco (UCSF) criteria.

Once-daily tacrolimus in liver transplantation: a 'me-too drug', or a therapeutic advantage

PURPOSE OF REVIEW

To provide latest information on differences between standard tacrolimus (TAC BID) and slow-released formulation of tacrolimus (Advagraf) in liver transplantation (LTx), and to discuss the latter's therapeutic value as a distinct entity.

RECENT FINDINGS

Two articles on de-novo studies, several on conversion and one on survival analysis from the European Liver Transplant Registry published recently showed that low-dose Advagraf immediately after transplantation provided same protection to the kidney as standard dose delayed until day 5, and was associated with lower rejection rate; to maintain the same trough level after late conversion to Advagraf, an approximately 1.25-fold higher dose was needed on average; if studied by questionnaire, conversion improved medication adherence; and registry data provided evidence of long-term survival benefit of Advagraf over TAC BID (7 and 8% graft and patient survival rates over a 3-year period; P < 0.002 and P < 0.003, respectively).

SUMMARY

Pharmacokinetic differences between TAC BID and Advagraf translate into less interpatient and intrapatient variability and improve adherence. If survival benefit of Advagraf administration de novo after LTx as demonstrated by the European Liver Transplant Registry analysis is confirmed in an independent cohort, Advagraf will leave the area of the 'me-too' drugs to become the immunosuppressant of choice.

Emerging drugs for prevention of T-cell mediated rejection in liver and kidney transplantation

INTRODUCTION

Acute and chronic graft rejection continues to be an important problem after solid organ transplantation. With the introduction of potent immunosuppressive agents such as calcineurin inhibitors, the risk of rejection has been significantly reduced. However, the adverse effects of life-long immunosuppression remain a concern, and there exist a fine balance between over-immunosuppression and risk of rejection. Areas covered: In this review, the current standard of care in immunosuppressive therapy, including the use of steroids, calcineurin inhibitors, mycophenolate prodrugs and mammalian target of rapamycin inhibitors, will be discussed. Newer immunosuppressive agents showing promising early data after liver and kidney transplantation will also be explored. Expert Opinion: Currently, calcineurin inhibitors continue to be a vital component of immunosuppressive therapy after solid organ transplantation. Although minimization and avoidance strategies have been developed, the ultimate goal of inducing tolerance remains elusive. Newer emerging agents should have potent and specific immunosuppressive activity, with minimal associated side effects. An individualized approach should be adopted to tailor immunosuppression according to the different needs of recipients.

Maintenance immunosuppression for adults undergoing liver transplantation: a network meta-analysis

BACKGROUND

As part of liver transplantation, immunosuppression (suppressing the host immunity) is given to prevent graft rejections resulting from the immune response of the body against transplanted organ or tissues from a different person whose tissue antigens are not compatible with those of the recipient. The optimal maintenance immunosuppressive regimen after liver transplantation remains uncertain.

OBJECTIVES

To assess the comparative benefits and harms of different maintenance immunosuppressive regimens in adults undergoing liver transplantation through a network meta-analysis and to generate rankings of the different immunosuppressive regimens according to their safety and efficacy.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers until October 2016 to identify randomised clinical trials on immunosuppression for liver transplantation.

SELECTION CRITERIA

We included only randomised clinical trials (irrespective of language, blinding, or publication status) in adult participants undergoing liver transplantation (or liver retransplantation) for any reason. We excluded trials in which participants had undergone multivisceral transplantation or participants with established graft rejections. We considered any of the various maintenance immunosuppressive regimens compared with each other.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS using Bayesian methods and calculated the odds ratio, rate ratio, and hazard ratio (HR) with 95% credible intervals (CrI) based on an available-case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance.

MAIN RESULTS

We included a total of 26 trials (3842 participants) in the review, and 23 trials (3693 participants) were included in one or more outcomes in the review. The vast majority of the participants underwent primary liver transplantation. All of the trials were at high risk of bias, and all of the evidence was of low or very low quality. In addition, because of sparse data involving trials at high risk of bias, it is not possible to entirely rely on the results of the network meta-analysis. The trials included mainly participants undergoing primary liver transplantation of varied aetiologies. The follow-up in the trials ranged from 3 to 144 months. The most common maintenance immunosuppression used as a control was tacrolimus. There was no evidence of difference in mortality (21 trials; 3492 participants) or graft loss (15 trials; 2961 participants) at maximal follow-up between the different maintenance immunosuppressive regimens based on the network meta-analysis. In the direct comparison, based on a single trial including 222 participants, tacrolimus plus sirolimus had increased mortality (HR 2.76, 95% CrI 1.30 to 6.69) and graft loss (HR 2.34, 95% CrI 1.28 to 4.61) at maximal follow-up compared with tacrolimus. There was no evidence of differences in the proportion of people with serious adverse events (1 trial; 719 participants), proportion of people with any adverse events (2 trials; 940 participants), renal impairment (8 trials; 2233 participants), chronic kidney disease (1 trial; 100 participants), graft rejections (any) (16 trials; 2726 participants), and graft rejections requiring treatment (5 trials; 1025 participants) between the different immunosuppressive regimens. The network meta-analysis showed that the number of adverse events was lower with cyclosporine A than with many other immunosuppressive regimens (12 trials; 1748 participants), and the risk of retransplantation (13 trials; 1994 participants) was higher with cyclosporine A than with tacrolimus (HR 3.08, 95% CrI 1.13 to 9.90). None of the trials reported number of serious adverse events, health-related quality of life, or costs.

FUNDING

14 trials were funded by pharmaceutical companies who would benefit from the results of the trial; two trials were funded by parties who had no vested interest in the results of the trial; and 10 trials did not report the source of funding.

AUTHORS' CONCLUSIONS

Based on low-quality evidence from a single small trial from direct comparison, tacrolimus plus sirolimus increases mortality and graft loss at maximal follow-up compared with tacrolimus. Based on very low-quality evidence from network meta-analysis, we found no evidence of difference between different immunosuppressive regimens. We found very low-quality evidence from network meta-analysis and low-quality evidence from direct comparison that cyclosporine A causes more retransplantation compared with tacrolimus. Future randomised clinical trials should be adequately powered; performed in people who are generally seen in the clinic rather than in highly selected participants; employ blinding; avoid postrandomisation dropouts or planned cross-overs; and use clinically important outcomes such as mortality, graft loss, renal impairment, chronic kidney disease, and retransplantation. Such trials should use tacrolimus as one of the control groups. Moreover, such trials ought to be designed in such a way as to ensure low risk of bias and low risks of random errors.

Influence of tacrolimus metabolism rate on renal function after solid organ transplantation

The calcineurin inhibitor (CNI) tacrolimus (TAC) is an integral part of the immunosuppressive regimen after solid organ transplantation. Although TAC is very effective in prevention of acute rejection episodes, its highly variable pharmacokinetic and narrow therapeutic window require frequent monitoring of drug levels and dose adjustments. TAC can cause CNI nephrotoxicity even at low blood trough levels (4-6 ng/mL). Thus, other factors besides the TAC trough level might contribute to CNI-related kidney injury. Unfortunately, TAC pharmacokinetic is determined by a whole bunch of parameters. However, for daily clinical routine a simple application strategy is needed. To address this problem, we and others have evaluated a simple calculation method in which the TAC blood trough concentration (C) is divided by the daily dose (D). Fast TAC metabolism (C/D ratio < 1.05) was identified as a potential risk factor for an inferior kidney function after transplantation. In this regard, we recently showed a strong association between fast TAC metabolism and CNI nephrotoxicity as well as BKV infection. Therefore, the TAC C/D ratio may assist transplant clinicians in a simple way to individualize the immunosuppressive regimen.

Serial Liver Stiffness Measurements and Monitoring of Liver-Transplanted Patients in a Real-Life Clinical Practice

BACKGROUND

Liver transplanted patients need close surveillance for early signs of graft disease.

OBJECTIVES

Transient elastography can safely be repeated over time, offering serial liver stiffness measurement values. Serial stiffness measurements were compared to single baseline stiffness measurements in predicting the appearance of liver-related clinical events and guiding subsequent clinical decisions.

METHODS

One hundred and sixty liver transplanted patients were observed for three years in our real-life practice.

RESULTS

Liver stiffness measurements were stable in 75% of patients, decreased in 4% of patients, and increased in 21% of patients. The pattern of increased stiffness measurements was associated with both HCV-RNA positive status and the presence of an active biliary complication of liver transplantation and was more predictive of a clinically significant event resulting from any disease of the transplanted liver when compared to a stable pattern or to a single liver stiffness measurement. The procedures that were consequently performed were often diagnostic for unexpected situations, both in HCV-RNA positive and HCV-RNA negative patients.

CONCLUSIONS

The pattern of longitudinally increased liver stiffness measurements efficiently supported clinical decisions for individualized management strategies. Repeated transient elastography in real-life clinical practice appears to have a practical role in monitoring liver transplanted patients.

A cost-utility analysis of prolonged-release tacrolimus relative to immediate-release tacrolimus and ciclosporin in liver transplant recipients in the UK

BACKGROUND

Calcineurin inhibitors (CNIs) represent the cornerstone of immunosuppressive therapy after liver transplantation. A recent network meta-analysis (NMA) evaluated the relative efficacy of CNIs ciclosporin, prolonged-release (PR) tacrolimus, and immediate-release (IR) tacrolimus in adult liver transplant recipients based on randomized and large observational trials published since 2000. Based on the NMA findings, the present study evaluated the cost-utility of PR tacrolimus relative to ciclosporin or IR tacrolimus in liver transplant recipients in the UK.

METHODS

A Markov model was developed to evaluate the cost-utility of immunosuppressive regimens in liver transplant recipients, capturing costs associated with immunosuppression, retransplantation, acute rejection (AR), and cytomegalovirus infection. Mortality, graft loss, and AR odds ratios were derived from the NMA. Costs were taken from the British National Formulary and the NHS National Tariff and expressed in 2016 pounds sterling. Future costs and effects were discounted at 3.5% annually.

RESULTS

Over 25 years, PR tacrolimus resulted in increased life expectancy and quality-adjusted life expectancy (QALE) relative to IR tacrolimus and ciclosporin. Relative to ciclosporin, QALE increased by 1.17 quality-adjusted life years (QALYs) with PR tacrolimus while costs increased by GBP £4645, yielding an incremental cost-effectiveness ratio (ICER) of £3962 per QALY gained. Relative to IR tacrolimus, QALE increased by 0.78 QALYs and costs by £1474, resulting in an ICER of £1889 per QALY gained. Sensitivity analysis showed the analysis to be most sensitive to dosing assumptions.

CONCLUSIONS

Based on a UK-specific analysis of the projected cost-utility of PR tacrolimus relative to IR tacrolimus and ciclosporin, PR tacrolimus was cost-effective, improving life expectancy and QALE relative to both IR tacrolimus and ciclosporin, yielding ICERs below £20 000 per QALY gained. The main limitations of the study were data source heterogeneity and omitting the economic and clinical effects of treating aspects of recurrent liver disease.

''Minimizing tacrolimus'' strategy and long-term survival after liver transplantation

AIM: To investigate the effect of the ‘‘minimizing tacrolimus’’ strategy on long-term survival of patients after liver transplantation (LT).

METHODS: We conducted a retrospective study of 319 patients who received LT between January 2009 and December 2011 at the First Affiliated Hospital of Zhejiang University School of Medicine. Following elimination of ineligible patients, 235 patients were included in the study. The relationship between early tacrolimus (TAC) exposure and survival period was analyzed by Kaplan Meier curves. Adverse effects related to TAC were evaluated by the χ² test. Routine monitoring of blood TAC concentration (TC) was performed using the PRO-Trac^TM II Tacrolimus Elisa Kit (Diasorin, United States).

RESULTS: Of 235 subjects enrolled in the study, 124 (52.8%) experienced adverse effects due to TAC. When evaluating mean TC, the survival time of patients with a mean TC < 5 ng/mL was significantly shorter than that in the other groups (911.3 ± 131.6 d vs 1381.1 ± 66.1 d, 911.3 ± 131.6 d vs 1327.3 ± 47.8 d, 911.3 ± 131.6 d vs 1343.2 ± 83.1 d, P < 0.05), while the survival times of patients with a mean TC of 5-7, 7-10 and 10-15 ng/mL were comparable. Adverse effects due to TAC in all four groups were not significantly different. When comparing the standard deviation (SD) of TC among the groups, the survival time of patients with a SD of 2-4 was significantly longer than that in the other groups (1388.8 ± 45.4 d vs 1029.6 ± 131.3 d, 1388.8 ± 45.4 d vs 1274.9 ± 57.0 d, P < 0.05), while in patients with a SD < 2 and SD > 4, the survival time was not statistically different. Adverse effects experienced in all three groups were not statistically different. In Cox regression analysis, male patients and those with a primary diagnosis of benign disease, mean TC > 5 ng/mL and TC SD 2-4 had better outcomes.

CONCLUSION: The early ‘‘minimizing tacrolimus’’ strategy with a mean TC of 5-10 ng/mL and SD of 2-4 was beneficial in terms of long-term survival after LT.

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

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

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.

Severe fibrosis in patients with recurrent hepatitis C after liver transplantation: a French experience on 250 patients over 15 years (the Orfèvre study)

BACKGROUND AND AIMS

Recurrent hepatitis C after liver transplantation (LT) is associated with rapid fibrosis progression. The aim of this study was to evaluate the cumulative risk for severe fibrosis and the factors influencing it.

PATIENTS AND METHODS

Two hundred and fifty LT patients were included 1 to 15years after LT. Recurrence of chronic hepatitis C on liver graft was classified according to Metavir score.

RESULTS

Kaplan-Meyer estimates for actuarial progression to severe fibrosis (Metavir>F3) showed a probability of 15.2% and 44.5% at 5 and 10years, respectively. Predictive factors for progression to severe fibrosis were: use of tacrolimus as main CNI, recipient age at time of biopsy<55, donor age ≥45, graft HCV re-infection<3months, biologically suspected graft re-infection and lack of response to antiviral treatment after LT. Multivariate analysis disclosed that only donor age ≥45 (hazard ratio 2.243, 95%CI 1.264-3.983, P=0.0058) and lack of response to antiviral treatment (hazard ratio 2.816, 95%CI 1.227-6.464, P=0.0146) were associated to severe fibrosis.

CONCLUSIONS

Our study confirms that donor age ≥45 and lack of response to antiviral treatment after LT are major predictive factors of progression of HCV recurrence on liver graft.

REFINE: a randomized trial comparing cyclosporine A and tacrolimus on fibrosis after liver transplantation for hepatitis C

REFINE was a 12-month, prospective, open-label study in 356 patients receiving de novo liver transplantation for hepatitis C virus (HCV) cirrhosis, randomized to cyclosporine A (CsA) or tacrolimus with (i) no steroids, IL-2 receptor antibody induction and mycophenolic acid, or (ii) slow steroid tapering. The primary analysis population based on availability of liver biopsies comprised 165 patients (88 CsA, 77 tacrolimus). There was no difference in the primary endpoint, fibrosis stage ≥2 at 12 months, which occurred in 63/88 CsA-treated patients (71.6%) and 52/77 tacrolimus-treated patients (67.5%) (odds ratio [OR] 1.11; 95% CI 0.56, 2.21; p = 0.759). Similarly, no significant between-group difference occurred at month 24 (OR 1.15; 95% CI 0.47, 2.80; p = 0.767). Among steroid-free patients, fibrosis score ≥2 was significantly less frequent with CsA versus tacrolimus at month 12 (7/37 [18.9%] vs. 16/38 [42.1%]; p = 0.029). HCV viral load was similar in both the tacrolimus- and CsA-treated cohorts. Mean blood glucose was significantly higher with tacrolimus from day 15 onward. Biopsy-proven acute rejection, graft loss and death were similar. These results showed no differences in posttransplant HCV-induced liver fibrosis between patients treated with CsA or tacrolimus in steroid-containing regimens, whereas CsA in steroid-free protocols was associated with reduced severity of fibrosis progression at 1 year posttransplant.

Low incidence of Pneumocystis jirovecii pneumonia in an unprophylaxed liver transplant cohort

BACKGROUND

Liver transplant recipients are managed with a range of immunosuppressive regimens that place them at heightened risk of life-threatening opportunistic infections such as Pneumocystis jirovecii pneumonia (PJP). No routine PJP prophylaxis is used at out institution. We reviewed the incidence of PJP in this cohort of unprophylaxed liver transplant recipients.

METHODS

We examined all liver transplants performed between January 2000 and January 2012 in Ireland's National Liver Transplant Centre, St. Vincent's University Hospital, Dublin. Cases were identified through a computerized database and through the histopathology and microbiology registration system. The diagnosis of PJP was confirmed by identification of Pneumocystis cysts in bronchoalveolar lavage (BAL) fluid or on autopsy specimens using Grocott-Gomori methenamine-silver nitrate or modified Wright-Giemsa staining methods.

RESULTS

During the study period, 687 liver transplants were performed. We found 7 cases of PJP with an incidence rate of 0.84 per 1000 person transplant years. Five cases occurred within 12 months of transplant with 2 cases occurring at 56 and 60 months, respectively. Two cases were diagnosed at postmortem; 1 previously had negative cytology from BAL, while the other could not be bronchoscoped because of rapid deterioration in the clinical condition. Three of the 5 treated patients died.

CONCLUSIONS

The incidence of PJP in this cohort was very low, but the case fatality rate was high. Two cases occurred well after the usual recommended period of prophylaxis. In institutions with a very low risk of infection, targeted rather than universal prophylaxis may be reasonable.

Immunosuppression in HCV-positive liver-transplant recipients

PURPOSE OF REVIEW

The purpose of this review is to evaluate the historical and recent literature as it pertains to current immunosuppression regimens in hepatitis C virus (HCV)-positive (+) liver-transplant recipients.

RECENT FINDINGS

Recent findings suggest that there are unique differences between HCV transplant recipients and non-HCV transplant recipients, not only in the graft's inflammatory response, but also to the treatments used to prevent and combat rejection.

SUMMARY

HCV (+) transplant recipients present unique challenges. Over the years, there has been progress but there is clearly no consensus regarding the optimal immunosuppressive medications or drug regimens; however, there continues to be advancements in the management of patients with HCV. Though current studies do not provide clear evidence as to optimal immunosuppression, they do identify questions ideally addressed by large, randomized controlled trials.

Recurrent hepatitis C virus infection post liver transplantation: impact of choice of calcineurin inhibitor

Recurrence of hepatitis C virus infection following liver transplantation (LT) for hepatitis C is universal. After LT, hepatitis C is associated with accelerated fibrosis progression and reduced graft and patient survival. Furthermore, responses to antiviral therapy in patients with recurrent hepatitis C virus post-transplant are consistently sub-optimal. Calcineurin inhibitors (CNIs) like cyclosporine A (CsA) and tacrolimus continue to dominate immunosuppressive regimens in this population; however, there is still uncertainty as to whether either offers an advantage in terms of patient outcomes. Although tacrolimus demonstrates improved efficacy in the general LT population, differences have begun to emerge between these agents regarding diabetogenic potential, antiviral activity, and fibrosis progression in patients with hepatitis C. This review critically evaluates the existing literature, providing an overview of the reported differences, concluding that despite conflicting evidence, a potential benefit of CsA in patients with hepatitis C is supported by the data and warrants further investigation. Future studies examining the role of CNIs in hepatitis C virus-positive LT recipients are required to accurately examine the effects of CNIs on outcomes such as fibrosis progression, survival, and effects on response to antiviral therapy, to provide robust information that allows clinicians to make an informed choice concerning which CNI is best for their patients.

Early tacrolimus exposure after liver transplantation: relationship with moderate/severe acute rejection and long-term outcome

BACKGROUND & AIMS

Liver transplant (LT) patients might be overimmunosuppressed as recommendations for tacrolimus trough concentrations (TC) within 4-6 weeks after liver transplantation are set too high (10-15 ng/ml). Early tacrolimus exposure was evaluated in relation to acute rejection and long-term outcomes.

METHODS

Four hundred and ninety-three consecutive LT patients receiving tacrolimus as primary immunosuppression (1995-2008) were analyzed. Acute rejection was diagnosed using protocol biopsies at day 6.1 ± 2.5. Median follow-up was 7.3 years (IQR 3.9-10.5). Early tacrolimus exposure (<15 days) was evaluated against moderate/severe acute rejection, chronic rejection, graft loss, chronic renal impairment and mortality using multiple logistic and Cox regression.

RESULTS

Maintenance immunosuppression was tacrolimus monotherapy (48.1%), double therapy combination with antimetabolites or steroids (18%), or triple therapy combination with antimetabolites and steroids (33.9%). Histological grade of acute rejection was moderate in 157 cases (31.8%) and severe in 19 cases (3.9%). Tacrolimus TC>7 ng/ml on the day of protocol biopsy was associated with less moderate/severe rejection (23.8%) compared with<7 ng/ml (41.2%) (p = 0.004). Mean tacrolimus TC 7-10 ng/ml within 15 days after LT were associated with reduced risk of graft loss (RR = 0.46; p = 0.014) compared to TC 10-15 ng/ml. A peak TC>20 ng/ml within this period was independently related to higher mortality (RR = 1.67; p = 0.005), particularly due to cardiovascular events, infections and malignancy (RR = 2.15; p = 0.001). Early tacrolimus exposure did not influence chronic rejection (p = 0.58), or chronic renal impairment (p = 0.25).

CONCLUSIONS

During the first 2 weeks after LT, tacrolimus TC between 7 and 10 ng/ml are safe in terms of acute rejection and are associated with longer graft survival.

Living-donor liver transplantation and hepatitis C

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

Immunomodulating therapy in liver transplantation: principles and practice

Liver transplantation has enjoyed dramatic success as a treatment option for patients suffering from chronic end-stage liver diseases. It also serves as a definitive treatment for certain genetic conditions such as familial amyloidosis and primary oxalosis, and as a potential curative therapy in selected cases of primary liver cancer. Currently, over 50,000 patients are alive with functioning liver transplants. Liver transplantation owes its success to advances in surgical technique, improvements in anesthesia and critical care, and advances in treatment of post-transplant complications including improved therapies for cytomegalovirus infections. But perhaps the most important advances in liver transplantation arise in the context of improvements in our understanding of the molecular biology of transplant immunology and the development of new agents that allow for manipulation of immunological signaling pathways. These improvements in immunosuppressive therapy have dramatically increased both graft and patient survival.

Tacrolimus trough levels, rejection and renal impairment in liver transplantation: a systematic review and meta-analysis

We hypothesized that current trough concentrations of tacrolimus after liver transplantation are set too high, considering that clinical consequences of rejection are not severe while side effects are increased.We systematically reviewed 64 studies (32 randomized controlled trials and 32 observational studies) to determine how lower tacrolimus trough concentrations than currently recommended affect acute rejection rates and renal impairment. Among randomized trials the mean of tacrolimus trough concentration during the first month was positively correlated with renal impairment within 1 year (r = 0.73; p = 0.003), but not with acute rejection, either defined using protocol biopsies (r = -0.37; p = 0.32) or not (r = 0.11; p = 0.49). A meta-analysis of randomized trials directly comparing tacrolimus trough concentrations (five trials for acute rejection [n = 957] and two trials for renal impairment [n = 712]) showed that "reduced tacrolimus" trough concentrations (<10 ng/mL) within the first month after liver transplantation were associated with less renal impairment at 1 year (RR = 0.51 [0.38-0.69]), with no significant influence on acute rejection (RR = 0.92 [0.65-1.31]) compared to "conventional tacrolimus" trough levels (>10 ng/mL). Lower trough concentrations of tacrolimus (6-10 ng/mL during the first month) would be more appropriate after liver transplantation. Regulatory authorities and the pharmaceutical industry should allow changes of regulatory drug information.

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

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

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

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

Liver transplantation and hepatitis C

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

Evolving concepts in the selection of immunosuppression regimen for liver transplant recipients

The introduction of calcineurin inhibitor (CNI) based immunosuppression has revolutionized the field of liver transplantation by dramatically reducing the incidence of acute cellular rejection and prolonging patient and allograft survival. However, the introduction of CNIs has also come at the price of increased patient morbidity, particularly with regard to the well-known nephrotoxic effects of the medications. In an effort to minimize the adverse effects, immunosuppression regimen have evolved to include the use of various induction agents and purine synthesis inhibitors to limit the dose of CNI necessary to achieve low acute cellular rejection rates. Careful assessments of risks and benefits are needed as these newer agents have their own side effect profiles. In addition, the impact of newer immunosuppression regimen on hepatitis C (HCV) recurrence has not been completely elucidated. This review will provide an overview of the most common immunosuppression regimen used in liver transplantation and discuss their impact on acute cellular rejection, patient and allograft survival, and HCV recurrence.

Pharmacokinetics for once-daily versus twice-daily tacrolimus formulations in de novo liver transplantation: a randomized, open-label trial

Tacrolimus, a cornerstone immunosuppressant, is available as a twice-daily formulation (tacrolimus bid). A once-daily prolonged-release formulation (tacrolimus qd) has been developed. This 6-week, randomized, phase 2, multicenter, open-label, prospective trial in primary liver transplant recipients investigated and compared the pharmacokinetics (PK) of tacrolimus for qd and bid formulations. All patients received tacrolimus-based immunosuppression (tacrolimus qd, n = 67; bid, n = 62). PK data were available for 77 patients (tacrolimus qd, n = 45; bid, n = 32). Tacrolimus area under the curve (AUC) from 0 to 24 hours (AUC(0-24) ) at equivalent doses was approximately 50% lower for tacrolimus qd than for bid on day 1 (146 versus 264 ng · h/mL, respectively), but by day 14 was comparable between treatments (324 and 287 ng · h/mL, respectively) with higher tacrolimus qd doses. There was a strong correlation between AUC(0-24) and concentration at 24 hours for tacrolimus qd and bid (r = 0.92 and r = 0.76, respectively). Furthermore, the relationship between these 2 parameters (ie, the slope of the line) was also similar for the 2 formulations. Efficacy endpoints were comparable for both formulations at 6 weeks with no marked differences in incidence, nature, or severity of adverse events between treatments (although the study was not powered to draw efficacy conclusions). These results suggest that targeting the same trough levels will achieve similar total AUC over 24 hours for both tacrolimus qd and tacrolimus bid in de novo liver transplant recipients.

Effect of calcineurin inhibitors in the outcome of liver transplantation in hepatitis C virus-positive recipients

BACKGROUND

There is a paucity of good studies evaluating the impact of calcineurin inhibitors on posttransplantation outcome in hepatitis C virus (HCV)-infected liver transplant (LT) recipients.

METHODS

We sought to determine whether there are differences on posttransplantation survival and histologic recurrence in HCV-LT recipients based on initial immunosuppression (IS) by conducting a prospective study comparing tacrolimus (Tac) versus cyclosporine-based IS in patients undergoing LT between 2001 and 2007. Protocol liver biopsies were performed.

RESULTS

Baseline characteristics (demographics, liver function at LT, genotype distribution, donor, surgery, and IS except for the type of calcineurin inhibitor) did not differ between groups. Severe disease (defined as bridging fibrosis, cirrhosis, cholestatic hepatitis, or allograft loss or death because of recurrent disease in the first year) was present in 67 of 253 (26.5%) and was equally distributed in the CsA and Tac groups (27% vs. 26%; P=0.68). Two thirds of protocol biopsies performed at 1 year showed some fibrosis without differences between CsA and Tac groups (75% vs. 70%). Advanced fibrosis (bridging fibrosis and cirrhosis) was diagnosed in 30% CsA and 24.5% Tac patients (P=NS). No differences in survival at 1 and 7 years were observed (83% and 67% vs. 78% and 64%, respectively, P=0.4). In summary, in patients undergoing LT for HCV-related liver disease, posttransplantation outcome is not related to the calcineurin inhibitor used.

Update on liver transplantation

Indications for liver transplant are expanding and most patients can expect a long-term successful outcome. Who should receive this life-saving gift and how should they be managed in an era of diminishing donors and increasing demand?

Comparative study of the cellular pharmacodynamics of calcineurin inhibitors between patients with chronic renal failure awaiting renal transplantation and cirrhosis patients awaiting liver transplantation

The in vitro response of peripheral blood mononuclear cells (PBMCs) to the suppressive effects of calcineurin inhibitors is known to correlate with the clinical efficacy of drugs used in renal transplantations. The present study was conducted to examine the differences of PBMC responses to calcineurin inhibitors between chronic renal failure (CRF) patients awaiting renal transplantation and cirrhosis patients awaiting liver transplantation. The study included 99 CRF patients awaiting renal transplantation and 27 cirrhosis patients awaiting liver transplantation. Twenty milliliters of venous blood was taken 1-7 days before transplantation. The in vitro drug concentrations giving 50% inhibition of PBMC blastogenesis stimulated with concanavalin A (IC(50)s) were calculated. The suppressive effects of tacrolimus against PBMC blastogenesis were more than 10-100 times stronger than those of cyclosporine. The median IC(50) value for cyclosporine against the CRF PBMCs was not significantly different from the median IC(50) value against the cirrhosis PBMCs. In contrast, tacrolimus sensitivity in cirrhosis PBMCs is approximately seven times higher than that in CRF PBMCs. The median IC(50) value for tacrolimus against cirrhosis PBMCs was significantly lower and therefore the effect was stronger in comparison to the CRF PBMCs (p < 0.001). These data suggest that the PBMCs of cirrhosis patients, in comparison to those of CRF patients, are highly sensitive to the suppressive effect of tacrolimus. However, PBMC sensitivity to cyclosporine was not significantly different between the CRF and cirrhosis patients. These observations raise the possibility that treatment with tacrolimus, rather than cyclosporine, may therefore be a better choice to reduce the risks of allograft rejection in liver transplantation.

Renal function and cardiovascular risk profile after conversion from ciclosporin to tacrolimus: prospective study in 80 liver transplant recipients

BACKGROUND

Increased risk of cardiovascular and cerebrovascular disease in liver transplant recipients results in particular from the side effects of calcineurin inhibitor-based immunosuppressive therapy. Several studies have demonstrated a more favourable outcome for patients receiving tacrolimus (TAC) as compared with ciclosporin (CS).

AIM

To investigate the effects of conversion from CS to TAC on cardiovascular risk factors and renal function in liver transplant recipients.

METHODS

In a prospective study, all except two patients had chronic kidney disease stages 2-4 (n = 80), according to estimated glomerular filtration rate using the abbreviated Modification of Diet in Renal Disease equation.

RESULTS

Conversion was accompanied with a mean decrease of total cholesterol from 194.6 +/- 54.0 mg/dL to 175.8 +/- 44.2 mg/dL (P < 0.001), low density lipoprotein cholesterol from 106.7 +/- 39.2 mg/dL to 90.9 +/- 28.6 mg/dL (P < 0.001) and mean arterial blood pressure values from 102.2 +/- 13.2 mm Hg to 95.9 +/- 11.7 mm Hg (P < 0.001). Renal function remained stable. No cases of de novo diabetes mellitus were identified. The Framingham risk score was significantly reduced from 5.2 +/- 4.4 at baseline to 4.4 +/- 5.3 after 12 months (P = 0.006).

CONCLUSIONS

Conversion from CS to TAC has been shown to improve the cardiovascular risk profile and may retard further decline of renal function after liver transplantation.

A comprehensive review of immunosuppression used for liver transplantation

Since liver transplantation was approved for the treatment of end stage liver disease, calcineurin inhibitors (CNI's) have played a critical role in the preservation of allograft function. Unfortunately, these medications cause a variety of Side effects such as diabetes, hypertension and nephrotoxicity which in turn result in significant morbidity and reduced quality of life. A variety of newer immunosuppressants have been evaluated over the last decade in an attempt to either substitute for CNI's or use with reduced dose CNI's while still preserving allograft function However, current data does not recommend complete cessation of CNI's due to unacceptably high rates of allograft rejection. As these medications have their own unique adverse effects, a careful assessment on their risks and benefits is essential, particularly when additive or synergistic effects with CNI's may occur. Furthermore, the impact of these newer medications on the risk of hepatitis C recurrence and progression remains to be elucidated. Controlled trials are urgently required to assist transplant physicians with choosing the optimum immunosuppressive regimen for their patients. This review will discuss commonly used immunosuppressants prescribed in liver transplantation, emerging therapties and where appropriate, the impact of these medications on the recurrence of hepatitis C after liver transplantation.

Clinical Significance of the Cellular Pharmacodynamics of Tacrolimus in Living-Donor Liver Transplantation

Successful immunosuppressive therapy is critical for liver transplantation; however, a considerable number of patients experience fatal rejection or alternatively exhibit serious infection resulting from excessive immunosuppression. The in vitro tacrolimus response of peripheral blood mononuclear cells (PBMCs) before transplantation was compared to the clinical outcome up to 4 weeks after operation in 28 living-donor liver transplant recipients treated with tacrolimus. The tacrolimus IC50 values against concanavalin A-induced PBMC blastogenesis in vitro were calculated. These recipients were classified into two groups with the mean tacrolimus IC50 (0.18 ng/ml) as the cutoff point, after which the clinical outcome between the patient groups was compared. The allograft rejection incidence in the low-sensitivity group (IC50 < 0.18 ng/ml; n = 16) was 6/12 (50.0%), which was significantly higher than the incidence of 2/16 (12.5%) in the high-sensitivity group (IC50 > 0.18 ng/ml; n = 12) ( p = 0.0297). In contrast, the infection incidence in the high-sensitivity group was 6/16 (37.5%), which was significantly higher than that of the low-sensitivity group (1/12; 8.3%) ( p = 0.0401). These data suggest that patients exhibiting a low PBMC sensitivity to tacrolimus have a risk of rejection, whereas highly sensitive patients have a risk of infection in living-donor liver transplantations under tacrolimus therapy.