Graft survival following living-donor renal transplantation: a comparison of tacrolimus and cyclosporine microemulsion with mycophenolate mofetil and steroids

Effectiveness of Maintenance Immunosuppression Therapies in a Matched-Pair Analysis Cohort of 16 Years of Renal Transplant in the Brazilian National Health System

The maintenance of patients with renal transplant typically involves two or more drugs to prevent rejection and prolong graft survival. The calcineurin inhibitors (CNI) are the most commonly recommended medicines in combinations with others. While immunosuppressive treatment regimens are well established, there is insufficient long-term effectiveness data to help guide future management decisions. The study analyzes the effectiveness of treatment regimens containing CNI after renal transplantation during 16 years of follow-up with real-world data from the Brazilian National Health System (SUS). This was a retrospective study of 2318 SUS patients after renal transplantion. Patients were propensity score-matched (1:1) by sex, age, type and year of transplantation. Kaplan-Meier analysis was used to estimate the cumulative probabilities of survival. A Cox proportional hazard model was used to evaluate factors associated with progression to graft loss. Multivariable analysis, adjusted for diabetes mellitus and race/color, showed a greater risk of graft loss for patients using tacrolimus plus mycophenolate compared to patients treated with cyclosporine plus azathioprine. In conclusion, this Brazilian real-world study, with a long follow-up period using matched analysis for relevant clinical features and the representativeness of the sample, demonstrated improved long-term effectiveness for therapeutic regimens containing cyclosporine plus azathioprine. Consequently, we recommend that protocols and clinical guidelines for renal transplantation should consider the cyclosporine plus azathioprine regimen as a potential first line option, along with others.

Prospective randomized study of conversion from tacrolimus to cyclosporine A to improve glucose metabolism in patients with posttransplant diabetes mellitus after renal transplantation

Tacrolimus (TAC) increases the risk of posttransplant diabetes (PTDM) compared with cyclosporine A (CYC). The present 12-month, multicenter, investigator-driven, prospective, randomized study was designed to assess whether conversion from tacrolimus to CYC can reverse PTDM after renal transplantation. Predominantly white patients with PTDM according to the 2005 American Diabetes Association criteria were randomized to either replacement of TAC with CYC or continuation of their TAC-based regimen after stratification for type of glucose-lowering therapy, steroid therapy, and hepatitis C status. At 12 months, 14 of 41 patients with complete data in the CYC arm (34%; 95%CI 19%-49%) were free of diabetes, whereas this was the case in only 4 of 39 patients (10%; 95%CI 3%-20%) in the TAC arm (P = .01). At 12 months, 39% of patients in the CYC arm were off glucose-lowering medication vs 13% of patients in the TAC arm (P = .01). The CYC group decreased glycated hemoglobin level during the 12-month follow-up, resulting in significantly lower levels compared with the TAC group (6.0 ± 0.9% vs 7.1 ± 1.7% at 12 months; P = .002). In conclusion, replacement of TAC with CYC significantly improves glucose metabolism and has the potential to reverse diabetes during the first year after conversion. (EU Clinical Trials Register No. 2006-001765-42).

Immunosuppressive therapy for kidney transplantation in adults: a systematic review and economic model

BACKGROUND

End-stage renal disease is a long-term irreversible decline in kidney function requiring renal replacement therapy: kidney transplantation, haemodialysis or peritoneal dialysis. The preferred option is kidney transplantation, followed by immunosuppressive therapy (induction and maintenance therapy) to reduce the risk of kidney rejection and prolong graft survival.

OBJECTIVES

To review and update the evidence for the clinical effectiveness and cost-effectiveness of basiliximab (BAS) (Simulect(®), Novartis Pharmaceuticals UK Ltd) and rabbit anti-human thymocyte immunoglobulin (rATG) (Thymoglobulin(®), Sanofi) as induction therapy, and immediate-release tacrolimus (TAC) (Adoport(®), Sandoz; Capexion(®), Mylan; Modigraf(®), Astellas Pharma; Perixis(®), Accord Healthcare; Prograf(®), Astellas Pharma; Tacni(®), Teva; Vivadex(®), Dexcel Pharma), prolonged-release tacrolimus (Advagraf(®) Astellas Pharma), belatacept (BEL) (Nulojix(®), Bristol-Myers Squibb), mycophenolate mofetil (MMF) (Arzip(®), Zentiva; CellCept(®), Roche Products; Myfenax(®), Teva), mycophenolate sodium (MPS) (Myfortic(®), Novartis Pharmaceuticals UK Ltd), sirolimus (SRL) (Rapamune(®), Pfizer) and everolimus (EVL) (Certican(®), Novartis) as maintenance therapy in adult renal transplantation.

METHODS

Clinical effectiveness searches were conducted until 18 November 2014 in MEDLINE (via Ovid), EMBASE (via Ovid), Cochrane Central Register of Controlled Trials (via Wiley Online Library) and Web of Science (via ISI), Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects and Health Technology Assessment (The Cochrane Library via Wiley Online Library) and Health Management Information Consortium (via Ovid). Cost-effectiveness searches were conducted until 18 November 2014 using a costs or economic literature search filter in MEDLINE (via Ovid), EMBASE (via Ovid), NHS Economic Evaluation Database (via Wiley Online Library), Web of Science (via ISI), Health Economic Evaluations Database (via Wiley Online Library) and the American Economic Association's electronic bibliography (via EconLit, EBSCOhost). Included studies were selected according to predefined methods and criteria. A random-effects model was used to analyse clinical effectiveness data (odds ratios for binary data and mean differences for continuous data). Network meta-analyses were undertaken within a Bayesian framework. A new discrete time-state transition economic model (semi-Markov) was developed, with acute rejection, graft function (GRF) and new-onset diabetes mellitus used to extrapolate graft survival. Recipients were assumed to be in one of three health states: functioning graft, graft loss or death.

RESULTS

Eighty-nine randomised controlled trials (RCTs), of variable quality, were included. For induction therapy, no treatment appeared more effective than another in reducing graft loss or mortality. Compared with placebo/no induction, rATG and BAS appeared more effective in reducing biopsy-proven acute rejection (BPAR) and BAS appeared more effective at improving GRF. For maintenance therapy, no treatment was better for all outcomes and no treatment appeared most effective at reducing graft loss. BEL + MMF appeared more effective than TAC + MMF and SRL + MMF at reducing mortality. MMF + CSA (ciclosporin), TAC + MMF, SRL + TAC, TAC + AZA (azathioprine) and EVL + CSA appeared more effective than CSA + AZA and EVL + MPS at reducing BPAR. SRL + AZA, TAC + AZA, TAC + MMF and BEL + MMF appeared to improve GRF compared with CSA + AZA and MMF + CSA. In the base-case deterministic and probabilistic analyses, BAS, MMF and TAC were predicted to be cost-effective at £20,000 and £30,000 per quality-adjusted life-year (QALY). When comparing all regimens, only BAS + TAC + MMF was cost-effective at £20,000 and £30,000 per QALY.

LIMITATIONS

For included trials, there was substantial methodological heterogeneity, few trials reported follow-up beyond 1 year, and there were insufficient data to perform subgroup analysis. Treatment discontinuation and switching were not modelled.

FUTURE WORK

High-quality, better-reported, longer-term RCTs are needed. Ideally, these would be sufficiently powered for subgroup analysis and include health-related quality of life as an outcome.

CONCLUSION

Only a regimen of BAS induction followed by maintenance with TAC and MMF is likely to be cost-effective at £20,000-30,000 per QALY.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42014013189.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Aging Kidney and Aging-Related Disease

With the development of society and improvement of health care, the life span is much longer than before, which brings serious aging problems. Among all the aging problems, renal aging grows to be nonnegligible issue. The aging process of kidney is always accompanied with structural and functional changes. Molecular changes, including Klotho and Sirtuins, are the basic causes of phenotypical changes. Cell senescence and cell autophagy play fundamental roles in the process of renal aging. To effectively intervene in the process of renal aging, different methods have been tried separately, which could produce different effects. Effective intervention of renal aging could be meaningful for healthy state of the whole body.

Cyclosporine versus tacrolimus: cost-effectiveness analysis for renal transplantation in Brazil

OBJECTIVE To analyze the cost-effectiveness of treatment regimens with cyclosporine or tacrolimus, five years after renal transplantation. METHODS This cost-effectiveness analysis was based on historical cohort data obtained between 2000 and 2004 and involved 2,022 patients treated with cyclosporine or tacrolimus, matched 1:1 for gender, age, and type and year of transplantation. Graft survival and the direct costs of medical care obtained from the National Health System (SUS) databases were used as outcome results. RESULTS Most of the patients were women, with a mean age of 36.6 years. The most frequent diagnosis of chronic renal failure was glomerulonephritis/nephritis (27.7%). In five years, the tacrolimus group had an average life expectancy gain of 3.96 years at an annual cost of R$78,360.57 compared with the cyclosporine group with a gain of 4.05 years and an annual cost of R$61,350.44. CONCLUSIONS After matching, the study indicated better survival of patients treated with regimens using tacrolimus. Moreover, regimens containing cyclosporine were more cost-effective [corrected].

Obesity, metabolic syndrome and diabetes mellitus after renal transplantation: prevention and treatment

The prevalence of the metabolic syndrome in dialysis patients is high and further increases after transplantation due to weight gain and the detrimental metabolic effects of immunosuppressive drugs. Corticosteroids cause insulin resistance, hyperlipidemia, abnormal glucose metabolism and arterial hypertension. The calcineurin inhibitor tacrolimus is diabetogenic by inhibiting insulin secretion, whereas cyclosporine causes hypertension and increases cholesterol levels. Mtor antagonists are responsible for hyperlipidemia and abnormal glucose metabolism by mechanisms that also implicate insulin resistance. The metabolic syndrome in transplant recipients has numerous detrimental effects such as increasing the risk of new onset diabetes, cardiovascular disease events and patient death. In addition, it has also been linked with accelerated loss of graft function, proteinuria and ultimately graft loss. Prevention and management of the metabolic syndrome are based on increasing physical activity, promotion of weight loss and control of cardiovascular risk factors. Bariatric surgery before or after renal transplantation in patients with body mass index >35 kg/m(2) is an option but its long term effects on graft and patient survival have not been investigated. Steroid withdrawal and replacement of tacrolimus with cyclosporine facilitate control of diabetes, whereas replacement of cyclosporine and mtor antagonists can improve hyperlipidemia. The new costimulation inhibitor belatacept has potent immunosuppressive properties without metabolic adverse effects and will be an important component of immunosuppressive regimens with better metabolic risk profile. Medical treatment of cardiovascular risk factors has to take potential drug interactions with immunosuppressive medication and drug accumulation due to renal insufficiency into account.

Role of tacrolimus combination therapy with mycophenolate mofetil in the prevention of organ rejection in kidney transplant patients

Introduction:

Several new medications are now available for immunosuppression in the kidney transplant field. Tacrolimus and mycophenolate mofetil were first introduced for immunosuppression in renal transplantation in the mid 1990s. Since then, the combination of tacrolimus and mycophenolate mofetil has been evaluated in numerous clinical trials. The outcomes of these trials have varied due to differences in induction and/or maintenance therapy, drug dosing and monitoring protocols, and study design. The aim of this review is to analyze the literature critically and to provide an overview of tacrolimus and mycophenolate mofetil combination therapy in renal transplantation.

Cyclosporine Versus Tacrolimus in Immunosuppressive Maintenance Regimens in Renal Transplants in Brazil: Survival Analysis from 2000 to 2004

BACKGROUND

In Brazil, the National Health System (SUS) is responsible for almost all renal transplants. SUS protocols recommend using cyclosporine, in association with azathioprine and corticosteroids, to maintain the immunosuppression that is essential for successful renal transplant. Alternatively, cyclosporine can be replaced by tacrolimus.

OBJECTIVE

To evaluate the effectiveness of therapeutic schema involving cyclosporine or tacrolimus after renal transplant during a 60-month follow-up period.

METHODS

A historical cohort study, from 2000 to 2004, was conducted using 5686 patients who underwent renal transplant and received cyclosporine or tacrolimus. Uni - and multivariate analyses were performed using the Cox model to examine factors associated with progression to treatment failure.

RESULTS

Most of the patients were male, aged 38 years or older, for whom the most frequent primary diagnosis of chronic renal failure (CRF) was glomerulonephritis/nephritis. Higher risk of treatment failure was associated with: therapeutic regimen (tacrolimus, HR 1.38, 95% CI 1.14 to 1.67), patient age at transplantation (additional year, HR 1.01, 95% CI 1.00 to 1.02), donor type (deceased, HR 1.60, 95% CI 1.35 to 1.89), median time of dialysis prior to transplantation (>24 mo, HR 1.29, 95% CI 1.09 to 1.52), and primary CRF diagnosis (diabetes, HR 1.54, 95% CI 1.09 to 2.17).

CONCLUSIONS

The risk of treatment failure of patients receiving tacrolimus was observed to be 1.38 times that of those receiving cyclosporine, after adjusting the model for possible confounding factors such as patient sex, patient age, graft origin, prior time of dialysis, and cause of CRF. Our results were obtained from an observational study, and further studies are necessary to evaluate whether compliance with SUS clinical protocols could result in more effective care for renal transplant recipients.

Ciclosporina versus tacrolimus no transplante renal no Brasil: uma comparação de custos

No Brasil, o Sistema Único de Saúde (SUS) é responsável maioria dos transplantes renais. Para a manutenção dessas intervenções, os protocolos recomendam uso da ciclosporina ou tacrolimus, associado com corticosteróides e azatioprina ou micofenolato. Na perspectiva do SUS, realizou-se análise econômica sobre recursos ambulatoriais, hospitalares e medicamentos utilizados por paciente e grupo terapêutico. Foi construída coorte de 2000 a 2004, com 5.174 pacientes em transplantes renais e em uso de ciclosporina ou tacrolimus, identificados por relacionamento probabilístico em registros do SUS. A coorte continha 4.015 pacientes em uso de ciclosporina e 1.159 com tacrolimus. A maioria era do sexo masculino, idade < 38 anos, cujos diagnósticos primários mais freqüentes eram nefrites, doenças cardiovasculares e causas indeterminadas. Após 48 meses, observou-se gasto superior para transplantes renais em hospitais do Nordeste, doador cadáver, naqueles em diálises > 24 meses antes do transplantes renais e no grupo do tacrolimus. Constatou-se maior gasto total com recursos hospitalares, ambulatoriais e medicamentos para os transplantes renais em pacientes com esquemas com tacrolimus, quando comparados com o grupo da ciclosporina.

Impact of donor age on renal allograft function and survival

BACKGROUND

The lack of cadaveric donors coupled with a rapidly growing number of potential recipients have stimulated the implementation of several strategies, including the acceptance of older donors, to increase the organ pool and reduce the waiting list for kidney transplantation. However several studies have demonstrated higher incidences of delayed graft function and poor graft outcomes among kidneys harvested from older donors.

OBJECTIVE

The objective of this study was to evaluate the influence of donor age on the function and long-term survival of renal allografts.

PATIENTS

We performed a retrospective review of the clinical data from 441 adult kidney transplantation from cadaveric heart-beating donors performed in our unit from May 1989 to May 2007.

RESULTS

Recipients of kidney allografts from older donors were significantly older (49.2 vs 43.7 years; P < .0001) and had a higher incidence of delayed graft function (15.1% vs 5.4%; P = .005). Renal function was superior following kidney transplantation using younger donors not only at 3 months (P < .0001) and 12 months (P < .0001) posttransplantation, but also upon long-term follow-up at 60 months (P < .0001) and 96 months (P = .030). Allograft survival censored for death with a functioning graft and patient survival were not different when comparing older versus younger donors. Multivariate analysis confirmed the lack of correlation between donor age and allograft failure.

CONCLUSION

Donor age showed no influence on allograft survival. However, kidney allografts from older donors displayed lower first year and long-term renal function.

[Immunosuppressor treatment in kidney transplantation from a live donor]

Live-donor transplantations have features that can influence the posttransplantation immunosuppressor treatment: a good-quality kidney and good transplantation conditions, which allow immediate return to kidney function with a high glomerular filtration rate and a lower risk of acute rejection. Very few studies have specifically evaluated the immunosuppressor treatment in the receiver of a kidney from a live donor and many questions remain unanswered. Nevertheless, according to clinical experience, it seems reasonable to use an induction treatment of IL-2 receptor monoclonal antibodies in the receivers of live-donor kidneys (with the exception of HLA-identical transplantations) whether or not the two are related. As for maintenance treatment, it seems important to preserve the number of nephrons in the graft using proliferation signal inhibitors instead of anticalcineurins. On the other hand, for transplantations where the donor and receiver are HLA-identical, it is more difficult to make recommendations because of many unanswered questions, which will remain so as long as specific randomized trials are not conducted.

Renal transplantation in the elderly

Elderly patients are increasingly being considered for kidney transplantation due to a global explosion of the aging population with end-stage renal disease (ESRD). However, mounting scarcity of available organs for transplant has led to a wider disparity between organ supply and demand. Consequently, the criteria for accepting kidneys for transplantation have been extended in an attempt to allow the use of organs from elderly donors or those with significant co-morbidities, so-called "expanded criteria donor" (ECD) kidneys. Excellent outcomes have been achieved from ECD kidneys with appropriate donor and recipient profiling and selection. With increasing recovery efforts directed at older donors, the concept of age-matching is becoming more accepted as a method of optimizing utilization of organs in elderly donors and recipients. Utilization of pulsatile perfusion has further improved ECD outcomes and helped the decision-making process for the UNOS (United Network for Organ Sharing) offer. However, age-related immune dysfunction and associated co-morbidities make the elderly transplant recipients ever more susceptible to complications associated with immunosuppressive agents. Consequently, the elderly population is at a higher risk to develop infections and malignancy in the post-transplant period notwithstanding improved transplant outcomes. Appropriate immunosuppressive agents and dosages should be selected to minimize adverse events while reducing the risk of acute rejections and maximizing patient and renal allograft survival.

Risk factors for cardiovascular events after successful renal transplantation

BACKGROUND

Cardiovascular disease is a frequent cause of morbidity after renal transplantation. The aims of this study were to evaluate the incidence of cardiovascular events and to identify the main risk factors for cardiovascular complications and mortality in 2071 white adults with a renal transplant functioning for at least 1 year.

METHODS

Clinical events, routine biochemistry, and prescribed drugs at month 1, month 6, and yearly after transplantation were analyzed.

RESULTS

The incidence of cardiovascular events increased over time. At 15 years after transplantation, only 47% of surviving patients had not experienced any cardiovascular event. Risk factors associated with cardiovascular complications were male gender (P=0.04), age (P<0.0001), arterial hypertension before transplantation (P<0.0001), longer pretransplant dialysis (P<0.0001), cardiovascular event before transplantation (P<0.0001), older era of transplantation (P=0.0009), center-specific effect (P=0.003), posttransplant diabetes mellitus (P=0.01), increased pulse pressure after transplantation (P=0.02), intake of corticosteroids (P=0.016), intake of azathioprine (P=0.016), lower serum albumin after transplantation (P=0.004), and higher serum triglyceride levels after transplantation (P=0.007). The risk of death was increased in patients with low or elevated hematocrit, while it was minimal with values around 38%.

CONCLUSIONS

The occurrence of fatal and nonfatal cardiovascular events after successful renal transplantation not only relates to baseline cardiovascular risk factors present at transplantation, but also to immunosuppressive drugs and posttransplantation traditional and nontraditional risk factors.

[Transplantation from a living related donor: Results]

The results of transplantation from a living donor (LDT) are constantly better than those of cadaveric transplantation (2004 Report of the French Agency of Biomedicine: graft survival 80 versus 63% at 10 years). Transplantation from an HLA-identical sibling is in any case the best combination, but there is no significant difference in graft survival when the donor is a parent, a child, a non HLA-identical sibling, a spouse or an unrelated person. The reasons for these better results are several: the quality of the kidney transplant, the absence of brain death, the advantage of a programmed surgery and of preemptive transplantation. It is admitted now that HLA compatibility plays a minor role. As in cadaveric transplantation, acute rejection, delayed graft function, pretransplant HLA immunisation, age of the donor and the recipient and possibly the discrepancy between the weight of the donor and the recipient are determinants of transplant outcome.

Renal transplantation: older recipients and donors

The majority of patients receiving a renal allograft, including a kidney from an older donor, do well. Renal transplantation from a living donor is associated with distinct advantages, including prolonged allograft survival. When live donors are not available, however, deceased donor kidneys provide suitable renal function that frequently lasts the lifetime of elderly recipients. Elderly patients who receive a kidney transplant enjoy improved survival, better quality of life, and lower medical costs than those who remain on dialysis.

Mycophenolate mofetil dose reductions and discontinuations after gastrointestinal complications are associated with renal transplant graft failure

BACKGROUND

Mycophenolate mofetil (MMF) use in renal transplantation has steadily increased since 1995 because of its ability to lower the risks of rejection and chronic allograft nephropathy. However, significant gastrointestinal (GI) complications may lead to MMF dose reductions and discontinuations. Little is known of the association between MMF dose reductions and discontinuations following GI complications and graft survival.

METHODS

Using the United States Renal Data System, we identified 3,675 adult recipients (age >or=18) with a diagnosed GI complication who were prescribed MMF at the time of first GI diagnosis and had Medicare as their primary insurer. MMF doses were ascertained from Medicare payment records. We estimated risk of graft loss associated with MMF dose adjustments after GI diagnosis: dosage unchanged (reference), reduced <50%, reduced >or=50%, and MMF discontinued. Patients were followed until graft loss, death, last recorded immunosuppression prescription, or 3 years posttransplant.

RESULTS

Compared to those with no MMF dose reductions or discontinuations, the risk of graft failure increased with MMF doses reduction >or=50% (HR=2.36, 95% CI 1.23-4.54) and those with MMF discontinuation (2.72, CI 1.60-4.64).

CONCLUSION

Renal transplant recipients who underwent MMF dose reduction or withdrawal following GI diagnosis are associated with increased risk of graft failure.

Evaluation of the cost effectiveness of sirolimus versus tacrolimus for immunosuppression following renal transplantation in the UK

INTRODUCTION

Immunosuppressive therapy is required to prevent graft rejection. Calcineurin inhibitors such as tacrolimus are paradoxically toxic to the kidney, whereas sirolimus (rapamycin; Rapamune) is not generally associated with the nephrotoxicity of CNIs. The purpose of this study was to evaluate the relative cost utility of sirolimus versus tacrolimus for the primary prevention of graft rejection in renal transplant recipients in the UK.

METHODS

A stochastic simulation model was constructed using clinical trial and observational data comparing the two treatments. Time duration was up to 20 years. Costs were from a UK NHS perspective, valued at 2003 prices and discounted at 6%. Benefits were discounted at 1.5%. Simulated events included patient and graft survival, haemodialysis, peritoneal dialysis, re-transplants and acute rejection. Costs were summed for events and various maintenance therapies. Utility was differentially accredited depending upon survival and using the alternative renal replacement therapies. Outcome was predicted using post-transplant creatinine levels up to 3 years. Extensive statistical economic and sensitivity analyses were undertaken.

RESULTS

Over the 10-year horizon, sirolimus gained 0.72 years (discounted) of functioning graft over tacrolimus, resulting in an incremental cost per year of functioning graft that was dominant. Over a 20-year time horizon, the cost effectiveness of sirolimus over tacrolimus further improved with an average discounted gain in years of a functioning graft of 1.8 years, resulting in an incremental cost-utility ratio that was also dominant. The number of haemodialysis events was 48,243 for sirolimus recipients versus 127,829 for those receiving tacrolimus and peritoneal dialysis events 40,872 versus 105,249, respectively. Similar values were obtained when real-life observational data on tacrolimus use in Cardiff, Wales were entered into the model. Using data from Cardiff, sirolimus remained dominant over tacrolimus under all scenarios.

CONCLUSION

Our study suggests that sirolimus may be more cost effective than tacrolimus for the primary prevention of graft rejection in renal transplant recipients in the UK. Sirolimus was economically 'dominant' under almost all scenarios investigated. This finding was robust using statistical economic analysis and univariate sensitivity analysis.

Evaluation of the cost-effectiveness of Sirolimus versus cyclosporin for immunosuppression after renal transplantation in the United Kingdom

OBJECTIVE

The purpose of this study was to evaluate the cost-effectiveness of sirolimus compared with cyclosporin for the postsurgical management of renal transplant recipients, from the perspective of the UK National Health Service and the Personal Social Service.

METHODS

A discrete event stochastic simulation model was developed to evaluate both cost-effectiveness and cost utility over 10 and 20 years after transplant using historical data on 937 renal transplant recipients from the University Hospital of Wales in Cardiff, United Kingdom. The simulation was designed to forecast the incidence of acute rejection events, graft failure, retransplant, frequency of hemodialysis (HD) and peritoneal dialysis (PD), and death. Cox proportional hazard models were derived from historical transplant data, in which 1-, 2-, and 3-year post-transplant serum creatinine levels were used as the key drivers for predicting graft success and survival. Costs were reported as year-2003 UK pounds sterling (1 UK pound = US $1.76). Probabilistic sensitivity analysis was conducted and results reported with particular attention to 2 threshold values, 30,000/QALY and 20,000/QALY RESULTS: Over a 10-year time horizon, treatment with sirolimus was projected to produce a gain of 0.60 discounted year of functioning graft with a cost savings of 276 UK pounds per patient. Over a 20-year time horizon these benefits increased to 1.59 discounted years of functioning graft and a cost savings of 7405 UK pounds per patient. Using sensitivity analysis of the 10-year model, the only factors found to cause the probability of exceeding a 30,000 ceiling to be >5% were the proportion of subjects maintaining continuous graft function and the use of low-dose cyclosporin. With the 20-year model, sirolimus maintained cost-effectiveness across most scenarios in sensitivity analysis.

CONCLUSIONS

In this model analysis, sirolimus was cost-effective compared with cyclosporin for 10 to 20 years after renal transplantation in the United Kingdom, from the perspective of the UK National Health Service and Personal Social Service.

Strategies for minimizing immunosuppression in kidney transplantation

Immunosuppression remains the cause of most morbidity following organ transplantation. However, its use is also responsible for the outstanding graft and patient survival rates commonplace in modern transplantation. Thus, the predominant challenge for transplant clinicians is to provide a level of immunosuppression that prevents graft rejection while preserving immunocompetence against environmental pathogens. This review will outline several strategies for minimizing or tailoring the use of immunosuppressive drugs. The arguments for various strategies will be based on clinical trial data rather than animal studies. A distinction will be made between conventional immunosuppressive drug reduction based on over-immunosuppression, and newer induction methods specifically designed to lessen the need for chronic immunosuppression. Based on the available data we suggest that most patients can be transplanted with less immunosuppression than is currently standard.

Renal transplantation, immunosuppression and the skin: an update

Transplant medicine has seen many innovations over past decades and continues to evolve into the 21st century. Newer immunosuppressive strategies in renal transplantation are associated with better patient and graft survival rates; however, the adverse toxicities and long-term side effects associated with these agents present a number of challenges. Certain immunosuppressants are commonly used in dermatologic disorders, however, dermatologists may be less familiar with the clinical efficacy, side-effect profile, and dosage of newer immunosuppressive agents. A knowledge of the molecular and cellular mechanisms of action of these agents gives us a better understanding of how these agents contribute to the cutaneous and mucosal complications frequently seen post-transplant. With the advent of new immunosuppressive therapies and different treatment regimens, there is an increasing need for a multidisciplinary approach to balancing the risks and benefits of these medications to the individual transplant recipient. This review will highlight the different immunosuppressive agents and their effect on the skin while focusing on the evidence base to support the commonly used immunosuppressive regimes, newer protocols aimed at achieving maximum graft survival with minimal side effects, and important drug interactions with which all dermatologists should be familiar.

What is the calcineurin inhibitor of choice for pediatric renal transplantation?

Cyclosporine microemulsion (CyA) and tacrolimus (Tac) are the principal immunosuppressants prescribed for adult and pediatric renal transplantation. In the majority of patients, these calcineurin inhibitors have been used in combination with other immunosuppressive drugs, such as azathioprine or mycophenolate mofetil (MMF). In this review we will address the question of what calcineurin inhibitor we should use in an individual pediatric renal transplant patient. Well-designed randomized studies in children showed no difference in short-term patient and graft survival with cyclosporine microemulsion and tacrolimus. However Tac is significantly more effective than CyA microemulsion in preventing acute rejection after renal transplantation in a pediatric population when used in conjunction with azathioprine and corticosteroids. This difference disappears when calcineurin inhibitors are used in combination with MMF as both Tac and CyA produce similar rejection rates and graft survival. However, Tac is associated with improved graft function at 1 and 2 yr post-transplant. Adverse events of hypomagnesaemia and diarrhea seem to be higher in Tac group whereas hypertrichosis, flu syndrome and gum hyperplasia occurs more frequently in the CyA group. The incidence of post-transplant diabetes mellitus was almost identical between Tac and CyA treated patients. The recommendation drawn from the available data is that both CyA and Tac can be used safely and effectively in children. However Tac may be preferable to CyA because of steroid sparing effect and less hirsutism. We recommend that cyclosporine should be chosen when patients experience Tac-related adverse events. Nevertheless, the best calcineurin inhibitor should be decided on individual patients according to variable risk factors, such as risk of rejection in sensitized patient or delayed graft function. The possibility of adverse events should also be considered.

Experience with cyclosporine in the Canary Islands

Cyclosporine (CsA) is currently the basis of most immunosuppressive protocols after solid organ transplantation. The introduction of Neoral, a new microemulsion formulation of CsA, and more recently a range of adjunctive immunosuppressants have further enhanced short-term efficacy and tolerability of CsA-based immunosuppression. In addition, Neoral C2 monitoring has been shown to have advantages not only in the early posttransplant period, but also for maintenance transplant patients. The major long-term disadvantage associated with CsA is the development of nephrotoxicity and chronic allograft nephropathy (CAN), which is the second major cause of graft failure. Thus, strategies to reduce the risk of CAN include CsA-sparing protocols, use of C2 level monitoring, introduction of non-nephrotoxic adjunctive immunosuppressants, and optimal management of additional risk factors. Other important side effects related to CsA-based immunosuppression include hypertension, diabetes, and hyperlipidemia. Optimal management of these conditions may lead to significant reduction of cardiovascular-related morbidity and mortality following solid organ transplantation.

Cyclosporine: advantages versus disadvantages vis-à-vis tacrolimus

Despite a different molecular structure and biochemical properties, cyclosporine and tacrolimus--by inhibiting calcineurin activity--have been shown in the previous two decades of solid organ transplantation to be well tolerated and effective immunosuppressants. Initial randomized clinical trials showed a lower incidence of acute rejection in tacrolimus than in cyclosporine-treated patients, in combination with steroids and azathioprine. But in conjunction with mycophenolate mofetil, the difference in the incidence of acute rejection episodes is less clear. In general, short- and medium-term outcome variables (1-year serum creatinine, graft and patient survival) with cyclosporine and tacrolimus are excellent, and (almost) identical, with both substances having the same intrinsic nephrotoxic potential. On the other hand, cyclosporine and tacrolimus have a different impact on cardiovascular risk factors with tacrolimus having a better profile on arterial tension and lipid metabolism and cyclosporine on glucose metabolism. However, at present no data are available to discern that these differences in risk profile alter patient or graft survival or long-term cardiovascular morbidity/mortality. Therefore, prospective long-term trials are needed to study the quantitative impact of different immunosuppressive agents and concomitant cardiovascular risk factors on long-term patient and graft survival, before evidence-based (patient, graft, or cardiovascular) risk reduction can be firmly claimed by tailoring calcineurin inhibitors.