Everolimus with reduced calcineurin inhibitor in thoracic transplant recipients with renal dysfunction: a multicenter, randomized trial

Chronic renal insufficiency in heart transplant recipients: risk factors and management options

Renal dysfunction after heart transplantation is a frequently observed complication, in some cases resulting in significant limitation of quality of life and reduced survival. Since the pathophysiology of renal failure (RF) is multifactorial, the current etiologic paradigm for chronic kidney disease after heart transplantation relies on the concept of calcineurin inhibitor (CNI)-related nephrotoxicity acting on a predisposed recipient. Until recently, the management of RF has been restricted to the minimization of CNI dosage and general avoidance of classic nephrotoxic risk factors, with somewhat limited success. The recent introduction of proliferation signal inhibitors (PSIs) (sirolimus and everolimus), a new class of immunosuppressive drugs lacking intrinsic nephrotoxicity, has provided a completely new alternative in this clinical setting. As clinical experience with these new drugs increases, new renal-sparing strategies are becoming available. PSIs can be used in combination with reduced doses of CNIs and even in complete CNI-free protocols. Different strategies have been devised, including de novo use to avoid acute renal toxicity in high-risk patients immediately after transplantation, or more delayed introduction in those patients developing chronic RF after prolonged CNI exposure. In this review, the main information on the clinical relevance and pathophysiology of RF after heart transplantation, as well as the currently available experience with renal-sparing immunosuppressive regimens, particularly focused on the use of PSIs, is reviewed and summarized, including the key practical points for their appropriate clinical usage.

Plasma neutrophil gelatinase-associated lipocalin and worsening renal function during everolimus therapy after heart transplantation

Recently, the mammalian target of rapamycin inhibitor everolimus (EVL) has been introduced as a novel immunosuppressant for heart transplant (HTx) recipients, and is expected to preserve renal function compared to conventional calcineurin inhibitors (CNIs). However, a considerable number of recipients treated with EVL were not free from worsening renal function regardless of CNI reduction. Data were collected retrospectively from 27 HTx recipients who had received EVL (trough concentration, 3.1-9.2 ng/mL) along with reduced CNIs (%decreases in trough concentration, 27.3 ± 13.0%) because of switching from mycophenolate mophetil due to digestive symptoms or neutropenia, progressive coronary artery vasculopathy, or persistent renal dysfunction, and had been followed over 1 year between August 2008 and January 2013. Estimated glomerular filtration rate (eGFR) decreased in 5 recipients (18.5%) during the study period. Univariate logistic regression analysis demonstrated that a higher plasma neutrophil gelatinase-associated lipocalin (P-NGAL) level was the only significant predictor for a decrease in eGFR over a 1-year EVL treatment period among all baseline parameters (P = 0.008). eGFR and proteinuria worsened almost exclusively in patients with baseline P-NGAL ≥ 85 ng/mL, which was the cutoff value calculated by an ROC analysis (area under the curve, 0.955; sensitivity, 1.000; specificity, 0.955). In conclusion, higher P-NGAL may be a novel predictor for the worsening of renal function after EVL treatment that is resistant to CNI reduction in HTx recipients.

Prescription trends of immunosuppressive drugs in post-heart transplant recipients in Taiwan, 2000-2009

PURPOSE

Significantly increasing heart transplantations have been performed in Taiwan in the past decades, but the trends of maintenance immunosuppression for heart transplant recipients have not been well known. In this study, we aimed to explore the trends of maintenance immunosuppressive therapy and common complications for heart transplant recipients.

METHODS

We retrospectively analyzed ambulatory prescriptions in 488 heart transplant recipients for the period 2000-2009. Patient complications after heart transplantation were also identified.

RESULTS

The annual number of new heart transplant recipients ranged from 18 to 68. The 5-year survival rate was 77.9%. The total number of regimens was 10 in 2000, and increased to 28 in 2009. Most prescriptions were immunosuppressive combinations (95.5%-89.5%). The majority of immunosuppressive regimens were a triple regimen: cyclosporine, mycophenolic acid and corticosteroid in 2009. Cyclosporine was a predominant calcineurin inhibitor with a decreasing trend from 73.9% to 59.1%, whereas the use of tacrolimus significantly increased from 11.9% to 38.4%. Mycophenolic acid was the most frequently used antimetabolite (60.1%-80.3%), while the use of azathioprine was reduced (21.6%-2.3%). From 2008, the launch of everolimus initiated a new era in the utilization of mammalian target of rapamycin inhibitors for maintenance immunosuppression.

CONCLUSIONS

Cyclosporine remained the most frequently used calcineurin inhibitors, and tacrolimus increased gradually. Mycophenolic acid was the most popular antimetabolite rather than azathioprine. The rapidly increased everolimus combined regimen may change the patterns of maintenance immunosuppression. The increasing number of combination therapies indicates an active role of everolimus and a tendency of complex tailored individual therapies.

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

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

Immunosuppression in lung transplantation

Lung transplantation can be a life-saving procedure for those with end-stage lung diseases. Unfortunately, long term graft and patient survival are limited by both acute and chronic allograft rejection, with a median survival of just over 6 years. Immunosuppressive regimens are employed to reduce the rate of rejection, and while protocols vary from center to center, conventional maintenance therapy consists of triple drug therapy with a calcineurin inhibitor (cyclosporine or tacrolimus), antiproliferative agents [azathioprine (AZA), mycophenolate, sirolimus (srl), everolimus (evl)], and corticosteroids (CS). Roughly 50% of lung transplant centers also utilize induction therapy, with polyclonal antibody preparations [equine or rabbit anti-thymocyte globulin (ATG)], interleukin 2 receptor antagonists (IL2RAs) (daclizumab or basiliximab), or alemtuzumab. This review summarizes these agents and the data surrounding their use in lung transplantation, as well as additional common and novel therapies in lung transplantation. Despite the progression of the management of lung transplant recipients, they continue to be at high risk of treatment-related complications, and poor graft and patient survival. Randomized clinical trials are needed to allow for the development of better agents, regimens and techniques to address above mentioned issues and reduce morbidity and mortality among lung transplant recipients.

Everolimus initiation and early calcineurin inhibitor withdrawal in heart transplant recipients: a randomized trial

In a randomized, open-label trial, everolimus was compared to cyclosporine in 115 de novo heart transplant recipients. Patients were assigned within 5 days posttransplant to low-exposure everolimus (3–6 ng/mL) with reduced-exposure cyclosporine (n = 56), or standard-exposure cyclosporine (n = 59), with both mycophenolate mofetil and corticosteroids. In the everolimus group, cyclosporine was withdrawn after 7–11 weeks and everolimus exposure increased (6–10 ng/mL). The primary efficacy end point, measured GFR at 12 months posttransplant, was significantly higher with everolimus versus cyclosporine (mean ± SD: 79.8 ± 17.7 mL/min/1.73 m2 vs. 61.5 ± 19.6 mL/min/1.73 m2; p < 0.001). Coronary intravascular ultrasound showed that the mean increase in maximal intimal thickness was smaller (0.03 mm [95% CI 0.01, 0.05 mm] vs. 0.08 mm [95% CI 0.05, 0.12 mm], p = 0.03), and the incidence of cardiac allograft vasculopathy (CAV) was lower (50.0% vs. 64.6%, p = 0.003), with everolimus versus cyclosporine at month 12. Biopsy-proven acute rejection after weeks 7–11 was more frequent with everolimus (p = 0.03). Left ventricular function was not inferior with everolimus versus cyclosporine. Cytomegalovirus infection was less common with everolimus (5.4% vs. 30.5%, p < 0.001); the incidence of bacterial infection was similar. In conclusion, everolimus-based immunosuppression with early elimination of cyclosporine markedly improved renal function after heart transplantation. Since postoperative safety was not jeopardized and development of CAV was attenuated, this strategy may benefit long-term outcome.

Impact of the reduction of calcineurin inhibitors on renal function in heart transplant patients: a systematic review and meta-analysis

AIMS

Calcineurin inhibitors (CNIs) taken after heart transplantation lead to excellent short-term outcomes, but long-term use may cause chronic nephrotoxicity. Our aim was to identify, appraise, select and analyse all high-quality research evidence relevant to the question of the clinical impact of CNI-sparing strategies in heart transplant patients.

METHODS

We carried out a systematic review and meta-analysis of randomized controlled trials on CNI reduction in heart transplant recipients. Primary outcomes were kidney function and acute rejection after 1 year. Secondary outcomes included graft loss, all-cause mortality and adverse events.

RESULTS

Eight open-label studies were included, with 723 patients (four tested de novo CNI reduction and four maintenance CNI reduction). Calcineurin inhibitor reduction did not improve creatinine clearance at 12 months 5.46 [-1.17, 12.03] P = 0.32 I(2)  = 65.4%. Acute rejection at 12 months (55/360 vs. 52/332), mortality (18/301 vs. 15/270) and adverse event rates (55/294 vs. 52/281) did not differ between the low-CNI and standard-CNI groups. There was significant benefit on creatinine clearance in patients with impaired renal function at 6 months [+12.23 (+5.26, +18.82) ml min(-1) , P = 0.0003] and at 12 months 4.63 [-4.55, 13.82] P = 0.32 I(2)  = 75%.

CONCLUSIONS

This meta-analysis did not demonstrate a favourable effect of CNI reduction on kidney function, but there was no increase in acute rejection. To provide a better analysis of the influence of CNI reduction patterns and associated treatments, a meta-analysis of individual patient data should be performed.

Immunosuppression and allograft rejection following lung transplantation: evidence to date

The enduring success of lung transplantation is built on the use of immunosuppressive drugs to stop the immune system from rejecting the newly transplanted lung allograft. Most patients receive a triple-drug maintenance immunosuppressive regimen consisting of a calcineurin inhibitor, an antiproliferative and corticosteroids. Induction therapy with either an antilymphocyte monoclonal or an interleukin-2 receptor antagonist are prescribed by many centres aiming to achieve rapid inhibition of recently activated and potentially alloreactive T lymphocytes. Despite this generic approach acute rejection episodes remain common, mandating further fine-tuning and augmentation of the immunosuppressive regimen. While there has been a trend away from cyclosporine and azathioprine towards a preference for tacrolimus and mycophenolate mofetil, this has not translated into significant protection from the development of chronic lung allograft dysfunction, the main barrier to the long-term success of lung transplantation. This article reviews the problem of lung allograft rejection and the evidence for immunosuppressive regimens used both in the short- and long-term in patients undergoing lung transplantation.

The impact of genetic polymorphisms, diltiazem, and demographic variables on everolimus trough concentrations in lung transplant recipients

Everolimus (EVR) has inter-individual pharmacokinetic (PK) variability and a narrow therapeutic index. The study objective was to determine whether genetic polymorphisms, co-medications, and/or demographic variables accounted for inter-individual variability in EVR PK in lung transplant recipients (LTxR). LTxR were genotyped for ABCB1 c.1236C>T, ABCB1 c.2677G>T/A, ABCB1 c.3435C>T, CYP3A4*1B, CYP3A5*3, CYP2C8*2/*3/*4, and pregnane X receptor (NR1I2) c.44477T>C, c.63396C>T, c.69789A>G polymorphisms. The primary outcome was the difference in dose-adjusted EVR levels (EVR L/D) between ABCB1 diplotype groups (2 vs. 1 vs. 0 copies of the 1236C/2677G/3435C haplotype). Sixty-five LTxR were included. There was no significant difference in EVR L/D between ABCB1 CGC diplotype groups (CGC/CGC = 2.4 ± 1.1 [n = 9] vs. CGC/XXX = 2.5 ± 1.7 [n = 36] vs. XXX/XXX = 2.7 ± 1.7 ng/mL per mg/d [n = 20]; p = 0.9). CYP3A5*3, CYP3A4*1B, CYP2C8*3/*4, and NR1I2 polymorphisms were not associated with EVR L/D. EVR L/D was 3.4 ± 1.7 in LTxR receiving diltiazem (DILT) vs. 1.8 ± 1.1 ng/mL per mg/d in LTxR not receiving DILT (p <0.001). Demographic variables, including cystic fibrosis, were not associated with EVR PK. DILT use increased EVR L/D, but selected polymorphisms in ABCB1, CYP3A5, CYP3A4, CYP2C8, and NR1I2 did not affect EVR L/D in LTxR. Genotyping LTxR for these polymorphisms is unlikely to aid clinicians in optimizing EVR therapy.

Oedema, solid organ transplantation and mammalian target of rapamycin inhibitor/proliferation signal inhibitors (mTOR-I/PSIs)

Mammalian target of rapamycin inhibitor (mTOR-I)/proliferation signal inhibitors (PSI) including sirolimus and everolimus represent a new class of drugs increasingly used in solid-organ transplantation as alternatives to calcineurin inhibitors for patients with renal dysfunction, transplant coronary arterial vasculopathy or malignancy. The most frequently occurring mTOR-I/PSI-related adverse events are similar to those associated with other immunosuppressive therapies, but some side effects are more characteristic of proliferation signal inhibitors (e.g. lymphocele, arthralgia, oedema and hyperlipidaemia). The present paper review incidence, clinical presentation and mechanism of oedema within the clinical experience of mTOR-I/PSI in solid organ transplantation.

Plasma NGAL and glomerular filtration rate in cardiac transplant recipients treated with standard or reduced calcineurin inhibitor levels

AIM

Predictors of renal recovery following conversion from calcineurin inhibitor- to proliferation signal inhibitor-based therapy are lacking. We hypothesized that plasma NGAL (P-NGAL) could predict improvement in glomerular filtration rate (GFR) after conversion to everolimus.

PATIENTS & METHODS

P-NGAL was measured in 88 cardiac transplantation patients (median 5 years post-transplant) with renal dysfunction randomized to continuation of conventional calcineurin inhibitor-based immunosuppression or switching to an everolimus-based regimen.

RESULTS

P-NGAL correlated with measured GFR (mGFR) at baseline (R(2) = 0.21; p < 0.001). Randomization to everolimus improved mGFR after 1 year (median [25-75 % percentiles]: ΔmGFR 5.5 [-0.5-11.5] vs -1 [-7-4] ml/min/1.73 m(2); p = 0.006). Baseline P-NGAL predicted mGFR after 1 year (R(2) = 0.18; p < 0.001), but this association disappeared after controlling for baseline mGFR.

CONCLUSION

P-NGAL and GFR correlate with renal dysfunction in long-term heart transplantation recipients. P-NGAL did not predict improvement of renal function after conversion to everolimus-based immunosuppression.

Everolimus in heart transplantation: an update

The evidence base relating to the use of everolimus in heart transplantation has expanded considerably in recent years, providing clinically relevant information regarding its use in clinical practice. Unless there are special considerations to take into account, all de novo heart transplant patients can be regarded as potential candidates for immunosuppression with everolimus and reduced-exposure calcineurin inhibitor therapy. Caution about the use of everolimus immediately after transplantation should be exercised in certain patients with the risk of severe proteinuria, with poor wound healing, or with uncontrolled severe hyperlipidemia. Initiation of everolimus in the early phase aftertransplant is not advisable in patients with severe pretransplant end-organ dysfunction or in patients on a left ventricular assist device beforetransplant who are at high risk of infection or of wound healing complications. The most frequent reason for introducing everolimus in maintenance heart transplant patients is to support minimization or withdrawal of calcineurin inhibitor therapy, for example, due to impaired renal function or malignancy. Due to its potential to inhibit the progression of cardiac allograft vasculopathy and to reduce cytomegalovirus infection, everolimus should be initiated as soon as possible after heart transplantation. Immediate and adequate reduction of CNI exposure is mandatory from the start of everolimus therapy.

Use of mTOR inhibitors in chronic heart transplant recipients with renal failure: calcineurin-inhibitors conversion or minimization?

BACKGROUND

In the last decade, mTOR inhibitors (mTOR-is) have become the cornerstone of the calcineurin inhibitor (CNI)-reduced/free regimens aimed to the preservation of post-transplant renal function. We compared utility and safety of the total replacement of calcineurin inhibitors with a mTOR-i with a strategy based on calcineurin inhibitor minimization and concomitant use of m-TOR-i.

METHODS

In a retrospective multi-center cohort of 394 maintenance cardiac recipients with renal failure (GFR<60 mL/min/1.73 m(2)), we compared 235 patients in whom CNI was replaced with a mTOR-i (sirolimus or everolimus) with 159 patients in whom mTOR-is were used to minimize CNIs. A propensity score analysis was carried out to balance between group differences.

RESULTS

Overall, after a median time of 2 years from mTOR-i initiation, between group differences for the evolution of renal function were not observed. In a multivariate adjusted model, improvement of renal function was limited to patients with mTOR-i usage within 5years after transplantation, particularly with the conversion strategy, and in those patients who could maintain mTOR-i therapy. Significant differences between strategies were not found for mortality, infection and mTOR-i withdrawal due to drug-related adverse events. However, conversion group tended to have a higher acute rejection incidence than the minimization group (p=0.07).

CONCLUSION

In terms of renal benefits, our results support an earlier use of mTOR-is, irrespective of the strategy. The selection of either a conversion or a CNI minimization protocol should be based on the clinical characteristics of the patients, particularly their rejection risk.

Prevention and treatment of coronary artery vasculopathy

PURPOSE OF REVIEW

Cardiac allograft vasculopathy (CAV) is still one of the major causes of death following heart transplantation. Here, we review the recent advances in its prevention and treatment.

RECENT FINDINGS

Preventive measures comprise control of classical risk factors, prophylaxis against cytomegalovirus, avoidance of graft endothelial damage during heart transplantation, and prevention of acute rejection. These measures can be effective if begun early. The treatment options for established CAV are limited, percutaneous revascularization and coronary artery bypass graft only being viable for a minority of patients because of the diffuse nature of CAV. Retransplantation is the only definitive therapy for CAV and may be considered for suitable patients with advanced CAV and allograft dysfunction. One of the most promising developments in the recent years is the use of mTOR inhibitors, which can now be regarded as effective in preventing CAV in de novo patients; their role in the treatment of established CAV is still uncertain despite some encouraging recent findings.

SUMMARY

The implementation of measures and lifestyles that help prevent CAV should be a priority of postheart transplantation management. Research should urgently evaluate mTOR inhibitors for the treatment of established CAV.

Current strategies and future trends in immunosuppression after heart transplantation

PURPOSE OF REVIEW

Current immunosuppressive drugs have provided excellent outcomes after heart transplantation. However, more patients suffer from long-term complications of these drugs. A series of prospective randomized trials has been conducted and has offered disparate results. This report reviews the challenges of immunosuppressive therapy during the past decade, describes recent reports and explores potential future trends in immunosuppressive protocols in heart transplantation.

RECENT FINDINGS

The traditional combination of cyclosporine, azathioprine and steroids has been changed to tacrolimus (Tac) or cyclosporine in combination with mycophenolate mofetil (MMF) and steroids due to the results of several trials. The use of mammalian target of rapamycin inhibitors in combination with Tac or cyclosporine A has not shown a clear benefit compared with MMF. All different combinations have shown some positive effects counteracted by side-effects and negative synergism of combinations. Future protocols need to be adapted according to individual patient's needs and risks.

SUMMARY

The changing population of heart transplantation patients has become older and sicker. Immunosuppression strategies should be developed for each patient based on their risk for rejection and their risk for developing important complications of immunosuppressive therapy.

Recommendations on the use of everolimus in lung transplantation

The antiproliferative effect of everolimus provides a therapeutic option in the immunosuppression therapy of lung transplantation, by reducing both the risk of acute rejection and the process of progressive fibrosis that determines chronic graft rejection. However, few data on the use of everolimus in lung transplantation have been published to date, and the specific indications of the drug, along with the most adequate time for its introduction or dosing, have not been defined yet. The aim of this article is to propose recommendations for the use of everolimus in lung transplant recipients, including indications, dosing schedules and the use of concomitant immunosuppression. This consensus document has been developed by experts of all the Spanish lung transplant groups from the review of the existing literature and the clinical experience.

A comprehensive review of everolimus clinical reports: a new mammalian target of rapamycin inhibitor

As new immunosuppressive agents are introduced to the market, clinicians are faced with the daunting task of sifting through the published literature to decide the value that the agent will add to their own practice. We often must extrapolate information provided through study in other solid-organ transplantation populations than our specific area of interest as we interpret the results and outcomes. With these challenges in mind, this compilation of published work for the newest mammalian target of rapamycin inhibitor everolimus (Certican; Novartis Pharmaceuticals, Hanover, NJ) (Zortress; Novartis Pharmaceuticals, Basel, Switzerland) is intended to provide a concise but thorough presentation of available literature so that the reader who may be unfamiliar with the agent can make their own judgment. Both Ovid and PubMed search engines were queried with a particular focus on high-impact articles noted in the Web of Science or Citation Index. Work described solely in abstract or case report form was excluded, as well as meta-analyses or those that were editorial or commentary in nature. Included were publications presented using the English language that described adult human subjects who received a heart, lung, kidney, or liver allograft. The goal of this strategy was to allow for the inclusion of pertinent literature in an unbiased fashion. Tables are provided that outline trial specific information, leaving a discussion of major outcomes to the text of the review.

Everolimus and sirolimus in combination with cyclosporine have different effects on renal metabolism in the rat

Enhancement of calcineurin inhibitor nephrotoxicity by sirolimus (SRL) is limiting the clinical use of this drug combination. We compared the dose-dependent effects of the structurally related everolimus (EVL) and sirolimus (SRL) alone, and in combination with cyclosporine (CsA), on the rat kidney. Lewis rats were treated by oral gavage for 28 days using a checkerboard dosing format (0, 3.0, 6.0 and 10.0 CsA and 0, 0.5, 1.5 and 3.0 mg/kg/day SRL or EVL, n = 4/dose combination). After 28 days, oxidative stress, energy charge, kidney histologies, glomerular filtration rates, and concentrations of the immunosuppressants were measured along with ¹H-magnetic resonance spectroscopy (MRS) and gas chromatography- mass spectrometry profiles of cellular metabolites in urine. The combination of CsA with SRL led to higher urinary glucose concentrations and decreased levels of urinary Krebs cycle metabolites when compared to controls, suggesting that CsA+SRL negatively impacted proximal tubule metabolism. Unsupervised principal component analysis of MRS spectra distinguished unique urine metabolite patterns of rats treated with CsA+SRL from those treated with CsA+EVL and the controls. SRL, but not EVL blood concentrations were inversely correlated with urine Krebs cycle metabolite concentrations. Interestingly, the higher the EVL concentration, the closer urine metabolite patterns resembled those of controls, while in contrast, the combination of the highest doses of CsA+SRL showed the most significant differences in metabolite patterns. Surprisingly in this rat model, EVL and SRL in combination with CsA had different effects on kidney biochemistry, suggesting that further exploration of EVL in combination with low dose calcineurin inhibitors may be of potential benefit.

Virtual histology assessment of cardiac allograft vasculopathy following introduction of everolimus--results of a multicenter trial

In this 12-month multicenter Scandinavian study, 78 maintenance heart transplant (HTx) recipients randomized to everolimus with reduced calcineurin inhibitor (CNI) exposure or continued standard CNI-therapy underwent matched virtual histology (VH) examination to evaluate morphological progression of cardiac allograft vasculopathy (CAV). Parallel measurement of a range of inflammatory markers was also performed. A similar rate of quantitative CAV progression was observed in the everolimus (n = 30) and standard CNI group (n = 48) (plaque index 1.9 ± 3.8% and 1.6 ± 3.9%, respectively; p = 0.65). However, VH analysis revealed a significant increase in calcified (2.4 ± 4.0 vs. 0.3 ± 3.1%; p = 0.02) and necrotic component (6.5 ± 8.5 vs. 1.1 ± 8.6%; p = 0.01) among everolimus patients compared to controls. The increase in necrotic and calcified components was most prominent in everolimus patients with time since HTx >5.1 years and was accompanied by a significant increase in levels of von Willebrand (vWF) factor (p = 0.04) and vascular cell adhesion molecule (VCAM) (p = 0.03). Conversion to everolimus and reduced CNI is associated with a significant increase in calcified and necrotic intimal components and is more prominent in patients with a longer time since HTx. A significant increase in vWF and VCAM accompanied these qualitative changes and the prognostic implication of these findings requires further investigation.

Cyclosporine immunosuppression does not prevent the production of donor-specific antibody capable of mediating allograft vasculopathy

BACKGROUND

Late cardiac graft rejection, primarily mediated by allograft vasculopathy (AV), remains a major limitation to cardiac transplantation, even in the face of significant calcineurin inhibitor (CNI) immunosuppression. The role played by alloantibody in AV is unclear. Evidence that CNI immunosuppression suppresses CD4(+) T-cell function would suggest that antibody production and effector function would be severely limited in CNI-treated patients. In this study we examine the capacity of CNI-treated animals to develop effective alloantibody that can mediate AV.

METHODS

Wild-type (WT) B6 mice were alloimmunized using donor splenocytes or a fully major histocompatibility complex-mismatched allogeneic abdominal aortic graft in the presence of CNI immunosuppression (30 or 50 mg/kg/day cyclosporine A). Anti-serum was harvested and tested using complement-dependent in vitro cytotoxicity assays. Anti-serum was passively transferred to immunodeficient RAG1(-/-) recipients of allogeneic grafts. C4d deposition was quantified in the allografts from WT recipients.

RESULTS

CNI immunosuppression did not prevent the development of alloantibody in response to either immunization method (p < 0.05). Passive transfer of anti-serum generated AV lesions in immunodeficient graft recipients and mediated complement-dependent destruction of donor cells (p < 0.05). C4d deposition was localized to the media of grafts of CNI treated animals.

CONCLUSIONS

CNI therapy does not prevent the production of alloantibody with the capacity to mediate AV. C4d deposition in the media suggests a role for medial smooth muscle cell loss in antibody-mediated AV lesion development in our model.

Cyclosporine lowering with everolimus versus mycophenolate mofetil in heart transplant recipients: long-term follow-up of the SHIRAKISS randomized, prospective study

BACKGROUND

Cyclosporine nephrotoxicity negatively impacts long-term outcome after heart transplantation (HT). We previously reported 1-year results from a randomized study showing that cyclosporine-lowering strategies based on everolimus or mycophenolate mofetil (MMF) are equally effective for reducing progression of renal dysfunction. It is unknown whether this efficacy could be maintained over the long term.

METHODS

Thirty-four recipients 1 to 4 years after HT and with 25 to 60 ml/min of creatinine clearance (CrCl) were randomized to everolimus with a very low dose (C(0): 50 to 90 ng/ml, n = 17) or MMF with low dose of cyclosporine (C(0): 100 to 150 ng/ml, n = 17). Follow-up was prolonged up to 3 years, and calculated CrCl was the main efficacy measure.

RESULTS

Cyclosporine was maintained at 70% and 30% lower than baseline in the everolimus and MMF arms, respectively, throughout the 3-year study period. CrCl remained stable in the everolimus patients (+7% from baseline; p = 0.7), but improved in the MMF patients (+20% from baseline; p < 0.01), with a trend toward improved values compared with everolimus patients (46 ± 12 vs 56 ± 15 ml/min; p = 0.06). Subgroup analysis revealed that baseline proteinuria markedly influenced the renal function response to everolimus: whereas in patients with baseline proteinuria CrCl significantly worsened (-20%; p = 0.04), it improved in those without (+15%; p = 0.03). Safety was comparable between the two study arms.

CONCLUSIONS

Cyclosporine nephrotoxicity improved after a prolonged dose reduction in patients receiving MMF. The everolimus-based strategy provided a similar benefit only to patients without baseline proteinuria. While raising caution against the universal use of everolimus for kidney protection, our long-term results support the need for customized approaches in the management of drug toxicities in maintenance HT recipients.

A retrospective 12-month study of conversion to everolimus in lung transplant recipients

BACKGROUND

Everolimus has potent antifibrotic effects that may potentially affect the clinical course of bronchiolitis obliterans syndrome (BOS) or provide nephroprotective immunosuppressive regimens for lung transplantation.

METHODS

We retrospectively assessed the 12-month outcomes of the conversion to everolimus among lung recipients in six Spanish centers.

RESULTS

From March 2005 to December 2007, 65 lung recipients who were at a mean posttransplantation time of 10.2 ± 7.9 months were converted to everolimus, mainly because of BOS (64.6%) or renal insufficiency (RI; 12.3%). The initial dose of everolimus was 1.9 ± 0.6 mg/d and the mean blood trough levels were stable over time (6.4 ± 2.8 ng/mL at 12 months). Conversion to everolimus allowed us to eliminate the calcineurin inhibitor (CNI) in 21% of patients. Among the overall population, the forced expiratory volume at 1 second (FEV(1)) and renal function remained stable. Mean FEV(1) did not change among the 35 (81%) patients surviving BOS at 12 months: preconversion FEV(1): 1.449.5 ± 641.9 mL vs 12-month FEV(1): 1420.0 ± 734.6 mL (P = .866). There was a significant improvement in renal function among the RI patients with mean glomerular filtration rates of 42.2 ± 15.2 mL/min/1.73 m(2) (P = .043) at 6 and 44.4 ± 18.8 mL/min/1.73 m(2) at 12 months, (P = .063) and a decrease in the use of CNIs from 1% of RI patients preconversion to 57% at 6 and 75% at 12 months. With a mean of 8.1- months follow-up (range: 1-31.3) overall survival was 84.6% at 1 year and 50% at 22.3 months. Progressive BOS was the main cause of death. Reasons for everolimus discontinuation were patient death (n = 10), lack of efficacy (n = 4), gastrointestinal adverse events (n = 2), and edema (n = 2).

CONCLUSIONS

BOS and RI were the main indications for conversion to everolimus among lung recipients. Conversion to everolimus improved renal function among patients converted because of RI. The present results were inconclusive regarding effects of everolimus on BOS.

Safety and efficacy of molecularly targeted agents in patients with metastatic kidney cancer with renal dysfunction

Multiple molecularly targeted agents (MTAs) have been approved for the management of metastatic renal cell carcinoma (mRCC). Sunitinib and mammalian target of rapamycin inhibitors (temsirolimus, everolimus) are primarily metabolized in the liver, whereas the metabolism of bevacizumab is unclear. There are limited data on the toxicity profile and the efficacy of these agents in patients with renal insufficiency (RI). This is clinically relevant, especially as about one-third of patients with mRCC have renal dysfunction. The primary objective was to assess the safety and efficacy of targeted agents in patients with mRCC with RI. Medical records of patients with mRCC at Wayne State University, started on sunitinib, temsirolimus, everolimus, or bevacizumab, were reviewed. Patients with a calculated creatinine clearance of less than or equal to 60 ml/min were deemed to have RI. Data on safety and efficacy of MTA therapy were collected and analyzed with respect to renal function. RI was observed in 33% of our patients with mRCC. The incidence of toxicities, responses, time to progression, and overall survival were not significantly different in patients with RI compared with patients with normal renal function. Patients with RI had larger median increases in blood pressure with sunitinib and bevacizumab, increased incidence of thyroid dysfunction with sunitinib, and increased incidence of rash and dose interruptions with mammalian target of rapamycin inhibitors, than did patients with normal renal function. In conclusion, RI was commonly observed in our patients with mRCC. Molecularly targeted agents are well tolerated, and efficacy seems to be maintained in patients with RI. Vigilant monitoring of hypertension would be recommended for patients receiving sunitinib and bevacizumab.

Renal function in children with heart transplantation after switching to CNI-free immunosuppression with everolimus

Renal impairment because of CNI contributes to long-term morbidity. Therefore, CNI avoiding or sparing treatment strategies are important. In this article, we describe the results of a CNI-free treatment protocol with regard to recovery of renal function. Twenty-eight patients with heart transplantation were switched from CNI regimen to everolimus and mycophenolate, when cGFR was <75 mL/min/1.73 m(2). In all patients, CNI was stopped, when everolimus trough levels of 5-8 ng/L were achieved. Serum creatinine and cGFR were determined before and after 6 and 12 months. Median serum creatinine decreased from 1.2 mg/dL (range 0.7-3.7) before everolimus to 1.0 (range 0.6-1.8) and 1.0 (range 0.5-1.9) mg/dL after 6 and 12 months. Median cGFR was 47.81 (range 18.3-72.6) mL/min/1.73 m(2) before everolimus and 63.1 (range 37.8-108.7) mL/min/1.73 m(2) at six months and 64.8 (range 37.7-106.6) mL/min/1.73 m(2) after 12 months. All changes from baseline to six and 12 months were statistically significant (p < 0.05). Adverse events were infections (n = 3) and rejections (n = 3). Therapy was discontinued in four patients. Conversion to CNI-free immunosuppression resulted in significant improvements of renal function within six months of CNI withdrawal. Side effects are common. However, more studies are required to demonstrate the effectiveness in children.

Conversion of long-term kidney transplant recipients from calcineurin inhibitor therapy to everolimus: a randomized, multicenter, 24-month study

BACKGROUND

Benefits of conversion from calcineurin inhibitor (CNI) to mammalian target of rapamycin inhibitor-based immunosuppression in long-term kidney transplant patients remain uncertain.

METHODS

ASCERTAIN was a 24-month, open-label, multicenter study. Kidney transplant patients more than 6 months posttransplant receiving CNI (baseline glomerular filtration rate [GFR] 30-70 mL/min/1.73 m) were randomized to everolimus with CNI elimination (n=127) or CNI minimization (n=144), or continued CNI unchanged (controls, n=123) to assess the effect on measured GFR at month 24 after randomization.

RESULTS

Renal function was stable in all groups to month 24. Mean measured GFR at month 24, the primary endpoint, was 48.0±22.0 mL/min/1.73 m, 46.6±21.1 mL/min/1.73 m, and 46.0±20.4 mL/min/1.73 m in the CNI elimination, CNI minimization, and control groups, respectively. Differences between CNI elimination (1.12 mL/min/1.73 m, 95% confidence interval [CI] -3.51 to 5.76, P=0.63) and CNI minimization (0.59 mL/min/1.73 m, 95% CI -3.88 to 5.07, P=0.79) versus controls at month 24 were nonsignificant that is, the primary endpoint was not met. No efficacy endpoint differed significantly between groups. Post hoc analyses showed that patients with baseline creatinine clearance (CrCl) more than 50 mL/min had a significantly greater increase in measured GFR after CNI elimination versus controls (difference 11.4 mL/min/1.73 m, 95% CI 2.1 to 20.8 mL/min/1.73 m, P=0.017). Adverse events resulted in discontinuation in 36 (28.3%) CNI elimination patients, 24 (16.7%) CNI minimization patients, and 5 (4.1%) controls (P<0.001 vs. CNI elimination; P=0.020 vs. CNI minimization).

CONCLUSION

Conversion to everolimus with CNI elimination or minimization a mean of 5.6 years after kidney transplantation had no overall renal benefit and was associated with more frequent adverse events and discontinuations. Patients with CrCl more than 50 mL/min may benefit from a change in therapy more than 6 months after renal transplantation.

Efficacy and Safety of Low-Dose Cyclosporine with Everolimus and Steroids in de novo Heart Transplant Patients: A Multicentre, Randomized Trial

A six-month, multicenter, randomized, open-label study was undertaken to determine whether renal function is improved using reduced-exposure cyclosporine (CsA) versus standard-exposure CsA in 199 de novo heart transplant patients receiving everolimus and steroids ± induction therapy. Mean C(2) levels were at the low end of the target range in standard-exposure patients (n = 100) and exceeded target range in reduced-exposure patients (n = 99) throughout the study. Mean serum creatinine at Month 6 (the primary endpoint) was 141.0 ± 53.1 μmol/L in standard-exposure patients versus 130.1 ± 53.7 μmol/L in reduced-exposure patients (P = 0.093). The incidence of biopsy-proven acute rejection ≥3A at Month 6 was 21.0% (21/100) in the standard-exposure group and 16.2% (16/99) in the reduced-exposure group (n.s.). Adverse events and infections were similar between treatment groups. Thus, everolimus with reduced-exposure CsA resulted in comparable efficacy compared to standard-exposure CsA. No renal function benefits were demonstrated; that is possibly related to poor adherence to reduced CsA exposure.

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

Data on the conversion of patients to everolimus after liver transplantation are sparse. A multicenter, retrospective study followed 240 maintenance liver transplant patients to analyze the current indications for everolimus conversion, the employed regimens and exposure levels, and the impact on efficacy and safety. The mean time from transplantation to the introduction of everolimus was 4.9 ± 5.2 years. The mean everolimus trough level was 7.3 ± 4.1 ng/mL at month 1 and 8.1 ± 4.7 ng/mL at month 12. At 12 months, 61.6% of the patients were no longer receiving calcineurin inhibitor (CNI) therapy. The mean estimated glomerular filtration rate (eGFR) according to the Cockcroft-Gault formula was 64.2 ± 30.0 mL/minute on day 0 and 68.4 ± 32.5 mL/minute at month 12 (P = 0.007). Among patients with baseline serum creatinine levels ≥ 130 μmol/L, the eGFR values were 44.3 ± 15.7 mL/minute on day 0 and 53.7 ± 26.0 mL/minute at month 12 (P = 0.003). Four patients (1.6%) developed mild or moderate biopsy-proven acute rejection. Adverse events led to everolimus discontinuation in 12.9% of the patients. After the initiation of everolimus, the mean white blood cell count decreased significantly, and the total cholesterol and triglyceride levels increased significantly. In this retrospective analysis of the largest cohort of maintenance liver transplant patients analyzed after their conversion to everolimus, more than 60% of the patients were kept free of CNIs with a very low risk of acute rejection and with an acceptable safety profile. Randomized trials in which maintenance liver transplant patients are switched to everolimus in response to clinical indications or preemptively are warranted.

Proliferation signal inhibitors and post-transplant malignancies in heart transplantation: practical clinical management questions

Although malignancy is a major threat to long-term survival of heart transplant (HT) recipients, clear strategies to manage immunosuppression in these patients are lacking. Several lines of evidences support the hypothesis of an anticancer effect of proliferation signal inhibitors (PSIs: mammalian target of rapamycin [mTOR] inhibitors) in HT recipients. This property may arise from PSI's ability to replace immunosuppressive therapies that promote cancer progression, such as calcineurin inhibitors or azathioprine, and/or through their direct biological actions in preventing tumor development and progression. Given the lack of randomized studies specifically exploring these issues in the transplant setting, a collaborative group reviewed current literature and personal clinical experience to reach a consensus aimed to provide practical guidance for the clinical conduct in HT recipients with malignancy, or at high risk of malignancy, with a special focus on advice relevant to potential role of PSIs.