Everolimus plus early tacrolimus minimization: a phase III, randomized, open-label, multicentre trial in renal transplantation

Renal function at 12 months of kidney transplantation comparing tacrolimus and mycophenolate with tacrolimus and mTORi in donors with different KDPI ranges. A multicenter cohort study using propensity scoring

Introduction

The combination of tacrolimus/mTORi compared to tacrolimus/mycophenolate (MMF) was shown to be safe in the TRANSFORM trial. For donors with a high KDPI (Kidney Donor Profile Index), however, there are no data to support the effectiveness of this regimen. The main objective of this study was to explore the influence of the KDPI on 12-month renal function (eGFR) in patients receiving mTORi or MMF.

Methods

Multicenter cohort study of four Brazilian services that use the tacrolimus with mTORi as a protocol. Data from 2008 to 2018 of the tacrolimus/mycophenolate (MMF) and tacrolimus/mTORi (mTORi) regimens in renal transplant recipients over 18 years old were collected. For better homogeneity, the propensity score was used. Afterward, the method used for group selection ("match") was the K-nearest neighbor (KNN) method. New analyses were performed on this new balanced sample, and two different subsamples were constituted based on the median KDPI.

Results

The global analysis (n = 870) showed that the major determinant of worse kidney function was high KDPI. Afterward, the three strata were analyzed. In the first stratum (KDPI up to 50), 242 patients were evaluated, with 121 in each group. The eGFR was 64 ml/min/1.73 m2 in the mTORi group compared to 63 in the MMF group, p = 0.4, and when imputed eGFR was evaluated, 61 in the mTORi and 53 in the MMF, p = 0.065. In the second stratum (KDPI from 50 to 85), 282 patients were evaluated, with 141 in each group. eGFR was 46 ml/min/1.73 m2 in mTORi compared to 48 in MMF, p = 0.4, and when imputed eGFR was evaluated, 40 mTORi and 41 MMF, p = 0.8. In the last stratum (KDPI higher than 85) with n = 126 and 63 cases per group, eGFR was 36 ml/min/1.73 m2 in mTORi compared to 39 in MMF, p = 0.2, and when imputed eGFR was evaluated, 30 mTORi and 34 MMF, p = 0.2.

Discussion

The regimen using mTOR inhibitor is an effective and safe regimen when compared to the standard regimen. In addition, the scheme seems to offer additional protection against infections and may be an important ally in cases of high risk for these pathologies.

Evaluation of T-Cell Immune Status of Reduced-Dose Cyclosporine and Everolimus Combination Therapy in Kidney Transplant Patients

BACKGROUND

Kidney transplantation (KT) outcomes have significantly improved with calcineurin inhibitors (CNIs) administration. In recent years, the dose of CNIs has been reduced, and everolimus (EVR) has been used in combination with CNIs to avoid complications from the long-term use of CNIs. However, T-cell immune responses to these protocols have not been fully evaluated. This study evaluated the anti-donor T-cell responses to our CNI-sparing regimen.

METHODS

Fifty-five de novo KT patients were enrolled. Three months after KT, the patients were randomly assigned to either the EVR group, which received low-dose cyclosporine (CsA) (n = 28), or the standard-exposure CsA control group (n = 27), which was treated with both mycophenolate mofetil and methylprednisolone. Graft function, adverse events, and immunologic status were evaluated 3 years after KT. Mixed lymphocyte reaction (MLR) assays were performed to evaluate anti-donor T-cell responses in KT patients.

RESULTS

Both groups maintained graft function well, but total cholesterol levels tended to increase annually in the EVR group. The incidence of cytomegalovirus (CMV) infection tended to be lower in the EVR group, regardless of the CMV serologic status. Immunologic evaluation by MLR assay showed that anti-donor T-cell responses were adequately maintained in both groups.

CONCLUSIONS

EVR starting 3 months after KT can reduce the trough levels of CsA without affecting graft function or compromising the immunosuppressive effects. The EVR combination protocol is expected to reduce CNI toxicity and improve long-term prognosis after KT.

Effects of NR1I2 and ABCB1 Genetic Polymorphisms on Everolimus Pharmacokinetics in Japanese Renal Transplant Patients

The purpose of this study was to evaluate the effects of NR1I2 (7635G>A and 8055C>T) and ABCB1 (1236C>T, 2677G>T/A, and 3435C>T) genetic polymorphisms on everolimus pharmacokinetics in 98 Japanese renal transplant patients. On day 15 after everolimus administration, blood samples were collected just prior to and 1, 2, 3, 4, 6, 9, and 12 h after administration. The dose-adjusted area under the blood concentration−time curve (AUC0-12) of everolimus was significantly lower in patients with the NR1I2 8055C/C genotype than in those with other genotypes (p = 0.022) and was significantly higher in male patients than female patients (p = 0.045). Significant correlations between the dose-adjusted AUC0-12 of everolimus and age (p = 0.001), aspartate transaminase (p = 0.001), and alanine transaminase (p = 0.005) were found. In multivariate analysis, aging (p = 0.008) and higher alanine transaminase levels (p = 0.032) were independently predictive of a higher dose-adjusted everolimus AUC0-12. Aging and hepatic dysfunction in patients may need to be considered when evaluating dose reductions in everolimus. In renal transplant patients, management using everolimus blood concentrations after administration may be more important than analysis of NR1I2 8055C>T polymorphism before administration.

Edema Associated With Everolimus de Novo

BACKGROUND

The appearance of edema limits the use of everolimus de novo together with tacrolimus and steroids in kidney transplantation. We aimed to investigate the frequency and characteristics of patients with edema and compare them according to the type of immunosuppression.

METHODS

We studied 150 kidney transplant recipients between 2015 and 2017 based on receiving everolimus de novo (group A) or mycophenolic acid derivatives (group B).

RESULTS

We analyzed 50 patients in group A and 100 in group B. Follow-up was 26.2 ± 10 months. Fifty-six patients presented edema (37.3%): 54% in group A and 29% in group B (P = .003). Edema was mild in 74% of patients in group A and 57.1% in group B. The probability of edema was 10.1%, 22.4%, and 41% at 3, 6, and 12 months, respectively, in group A vs 10.1%, 20.3%, and 25.4% in group B (P = .006). Patients were treated mostly with diuretics (14.3% in group A vs 27.6% in group B) and discontinuation of calcium channel blockers (46.4% in group A vs 48.3% in group B). Improvement was 70.4% in group A vs 60.7% in group B; patient worsening was 0% in group A vs 10.7% in group B; and there was no change in 29.6% in group A vs 28.6% in group B. We did not find differences in patient or graft survival in those who presented edema, regardless of the treatment group.

CONCLUSION

The use of everolimus and standard doses of tacrolimus caused edema in 54% of patients, with no impact on renal function or survival compared with mycophenolic acid derivatives. The edema was mostly of low intensity and improved in most patients.

An overview of the efficacy and safety of everolimus in adult solid organ transplant recipients

As the risk of graft loss due to acute rejection has declined, the goal of post-transplant management has switched to long-term preservation of organ function. Minimizing calcineurin inhibitor (CNI)-related nephrotoxicity is a key component of this objective. Everolimus is a mammalian target of rapamycin inhibitor/proliferation-signal inhibitor with potent immunosuppressive and anti-proliferative effects. It has been widely investigated in large randomized clinical studies that have shown it to have similar anti-rejection efficacy compared with standard-of-care regimens across organ transplant indications. With demonstrated potential to facilitate the reduction of CNI therapy and preserve renal function, everolimus is an alternative to the current standard-of-care CNI-based regimens used in de novo and maintenance solid organ transplantation recipients. Here, we provide an overview of the evidence from the everolimus clinical study program across kidney, liver, heart, and lung transplants, as well as other key data associated with its use in CNI reduction strategies in adult transplant recipients.

Drug-Drug Interaction between Tacrolimus and Vonoprazan in Kidney Transplant Recipients

Kidney transplant recipients with tacrolimus-based immunosuppressive therapy are often treated with proton-pump inhibitors (PPIs) to prevent gastric ulcer complications. Vonoprazan, a potassium-competitive acid blocker, is a novel PPI possessing different metabolic pathways from conventional PPIs (e.g., omeprazole, lansoprazole and rabeprazole). However, no data are available on the change in blood concentration of tacrolimus after switching rabeprazole, a conventional PPI, to vonoprazan coadministration in the initial period of post-transplantation. This is a retrospective study of 18 kidney transplant recipients. The blood concentration and the concentration to dose (C/D) ratio of tacrolimus were compared before and after switching from rabeprazole to vonoprazan. Impacts of CYP2C19 and CYP3A5 genetic polymorphisms on the drug-drug interaction were also examined. The median (range) trough concentration of tacrolimus was significantly increased from 5.2 (3.6-7.4) to 8.1 (6.1-11.7) ng/mL (p < 0.0005) after switching from rabeprazole to vonoprazan. The C/D ratio of tacrolimus was also significantly increased from 38.1 (16.5-138.1) to 48.9 (26.2-207.2) (p < 0.0005). The percent changes of tacrolimus concentrations and C/D were 65.8% and 41.8%, respectively. CYP2C19 and CYP3A5 genetic polymorphisms did not affect the change in concentration and C/D ratio of tacrolimus. The present study indicates that vonoprazan coadministration increases the tacrolimus concentration regardless of CYP2C19 or CYP3A5 genetic polymorphisms. Thus, frequent monitoring of blood tacrolimus concentration is required when vonoprazan is introduced as an intensive gastric acid blocker in the early phase of post-transplantation.

Development of an agglutination-enhancement immunoturbidimetric tacrolimus assay with improved sensitivity

Accurate quantification of low level of blood drugs by Latex enhanced immunoturbidimetric assay (LEITA) remains a challenge due to its inherent limited sensitivity. To deal with this problem, we designed a new agglutination-enhancement strategy, and applied it for development of a highly sensitive and accurate tacrolimus LEITA. By this principle, a very small amount of biotin labeled anti-tacrolimus monoclonal antibodies (BLATMA) can arise agglutination strong enough for accurate reading of the increased absorbance since the BLATMA bears multiple biotin molecules, and the agglutination mediated by BLATMA can be inhibited by a similarly small amount of tacrolimus when the drug binds to BLATMA, giving rise to an improved sensitivity. The limit of detection (LOD) and functional sensitivity obtained by the proposed tacrolimus LEITA was 0.22 ng/mL and 0.59 ng/mL, respectively, 8-20 times more sensitive than the conventional drug-latex or antibody-latex based direct inhibition LEITA formats. Good precision was observed in the whole range of clinically significant tacrolimus concentration. The reliability of the tacrolimus LEITA was demonstrated by its strong correlation with both liquid chromatography-tandem mass spectrometry (LC-MS/MS) (R² = 0.977, slope = 0.998) and the ABBOTT tacrolimus chemiluminescent magnetic immunoassay (CMIA) (R² = 0.982, slope = 1.01) in the analysis of 119 clinical samples. It's concluded that the agglutination-enhancement strategy can be applied to construct highly sensitive LEITA for accurate tacrolimus analysis; owing to the improved sensitivity, this technique can be expected not only to improve the reliability of LEITA for low-level drug monitoring, but also to broaden the scope of analytes detectable by LEITA.

Rationale and design of the OPTIMIZE trial: OPen label multicenter randomized trial comparing standard IMmunosuppression with tacrolimus and mycophenolate mofetil with a low exposure tacrolimus regimen In combination with everolimus in de novo renal transplantation in Elderly patients

BACKGROUND

In 2019, more than 30 % of all newly transplanted kidney transplant recipients in The Netherlands were above 65 years of age. Elderly patients are less prone to rejection, and death censored graft loss is less frequent compared to younger recipients. Elderly recipients do have increased rates of malignancy and infection-related mortality. Poor kidney transplant function in elderly recipients may be related to both pre-existing (i.e. donor-derived) kidney damage and increased susceptibility to nephrotoxicity of calcineurin inhibitors (CNIs) in kidneys from older donors. Hence, it is pivotal to shift the focus from prevention of rejection to preservation of graft function and prevention of over-immunosuppression in the elderly. The OPTIMIZE study will test the hypothesis that reduced CNI exposure in combination with everolimus will lead to better kidney transplant function, a reduced incidence of complications and improved health-related quality of life for kidney transplant recipients aged 65 years and older, compared to standard immunosuppression.

METHODS

This open label, randomized, multicenter clinical trial will include 374 elderly kidney transplant recipients (≥ 65 years) and consists of two strata. Stratum A includes elderly recipients of a kidney from an elderly deceased donor and stratum B includes elderly recipients of a kidney from a living donor or from a deceased donor < 65 years. In each stratum, subjects will be randomized to a standard, tacrolimus-based immunosuppressive regimen with mycophenolate mofetil and glucocorticoids or an adapted immunosuppressive regimen with reduced CNI exposure in combination with everolimus and glucocorticoids. The primary endpoint is 'successful transplantation', defined as survival with a functioning graft and an eGFR ≥ 30 ml/min per 1.73 m2 in stratum A and ≥ 45 ml/min per 1.73 m2 in stratum B, after 2 years, respectively.

CONCLUSIONS

The OPTIMIZE study will help to determine the optimal immunosuppressive regimen after kidney transplantation for elderly patients and the cost-effectiveness of this regimen. It will also provide deeper insight into immunosenescence and both subjective and objective outcomes after kidney transplantation in elderly recipients.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03797196 , registered January 9th, 2019. EudraCT: 2018-003194-10, registered March 19th, 2019.

Effect of Everolimus with Low-Dose Tacrolimus on Development of New-Onset Diabetes After Transplantation and Allograft Function in Kidney Transplantation: A Multicenter, Open-Label, Randomized Trial

Background

This randomized controlled trial aimed to investigate the effect of everolimus (EVL) with low-dose tacrolimus (Tac) on the development of post-transplantation diabetes mellitus (PTDM) in kidney transplantation (KT).

Material/Methods

Seventy-seven kidney transplant patients from 4 transplant centers were included. Patients were randomized to the “EVL group” (n=38) and the “TAC group” (n=39). The target Tac trough level was 2 to 5 ng/mL in the EVL group and 5 to 10 ng/mL in the TAC group.

Results

The 1-year cumulative incidence of PTDM in all patients was 7.8%, and no difference was found between the 2 groups (P=0.0819). Insulin resistance measured with the homeostatic model assessment for insulin resistance showed a significant increase only in the TAC group (1.11 to 1.30, P=0.0492). Allograft rejection rate and estimated glomerular filtration rate (eGFR) follow-ups every 3 months were not significantly different between the 2 groups. However, the EVL group showed a significant increase in the mean eGFR at 9 months and 12 months after KT compared to the baseline value (P=0.0242 and 0.0491, respectively).

The EVL group showed lower insulin resistance and higher allograft function in comparison to the TAC group.

Conclusions

EVL-based immunosuppressive therapy with lower Tac exposure could be a safer alternative for maintenance treatment.

Impact of Immunosuppressive Strategies on Post-Kidney Transplantation Thrombocytopenia

BACKGROUND

Thrombocytopenia after kidney transplantation is a common complication, partly induced by immunosuppressive therapies. Peritransplant thrombocytopenia may cause serious hemorrhages. We assessed the incidence of early posttransplantation thrombocytopenia (defined as a platelet count of <150,000 mm³ or <150 G/L) in de novo kidney transplant recipients (KTRs) across 4 immunosuppressive regimens.

METHODS

This was a single-center observational study that included all consecutive KTRs who received either Thymoglobulin (THY) or Grafalon (GRA) and maintenance therapy of either mycophenolate-mofetil (MMF) or everolimus (EVR), associated with tacrolimus/corticosteroids.

RESULTS

Between July 27, 2016, and September 7, 2018, 237 KTRs were included; 64.6% experienced thrombocytopenia within the first week. Thrombocytopenia was significantly more frequent (P = .004) among GRA-treated patients (73.4%) compared to THY-treated patients (61.3%). These patients also had lower nadir platelet count (120 ± 52 vs 142 ± 48 G/L; P = .002) and lower platelet count at discharge (227 ± 94 vs 243 ± 92 G/L; P = .25). More of the GRA-EVR group had thrombocytopenia (81.0% vs 61.4% in THY-MMF, 60.9% in THY-EVR, and 69.8% in GRA-MMF; P = .081) and a worse nadir platelet count (109 ± 41 in GRA-EVR vs 141 ± 47G/L in THY-MMF, 145 ± 52 G/L in THY-EVR, and 125 ± 56 G/L in GRA-MMF; P = .011) but GRA was the only risk factor for thrombocytopenia in multivariate analyses (P = .002). Rates of hemorrhage, red blood cell transfusions, reoperations needed within the first week, delayed graft function, acute rejection, graft loss, and death did not differ between the groups after a mean follow-up of 25 ± 8 months.

CONCLUSIONS

GRA associated with EVR led to more frequent and severe thrombocytopenia, although we found no significant clinical consequences.

Use of De Novo mTOR Inhibitors in Hypersensitized Kidney Transplant Recipients: Experience From Clinical Practice

BACKGROUND

It is commonly believed that mTOR inhibitors (mTORi) should not be used in high-immunological risk kidney transplant recipients due to a perceived increased risk of rejection. However, almost all trials that examined the association of optimal-dose mTORi with calcineurin inhibitor (CNI) have excluded hypersensitized recipients from enrollment.

METHODS

To shed light on this issue, we examined 71 consecutive patients with a baseline calculated panel reactive antibody (cPRA) ≥50% that underwent kidney transplantation from June 2013 to December 2016 in our unit. Immunosuppression was based on CNI (tacrolimus), steroids and alternatively mycophenolic acid (MPA; n = 38), or mTORi (either everolimus or sirolimus, n = 33, target trough levels 3-8 ng/mL).

RESULTS

Demographic and immunological risk profiles were similar, and almost 90% of patients in both groups received induction with lymphocyte-depleting agents. Cox-regression analysis of rejection-free survival revealed better results for mTORi versus MPA in terms of biopsy-proven acute rejection (hazard ratio [confidence interval], 0.32 [0.11-0.90], P = 0.031 at univariable analysis and 0.34 [0.11-0.95], P = 0.040 at multivariable analysis). There were no differences in 1-year renal function, Banff chronicity score at 3- and 12-month protocol biopsy and development of de novo donor-specific antibodies. Tacrolimus trough levels along the first year were not different between groups (12-mo levels were 8.72 ± 2.93 and 7.85 ± 3.07 ng/mL for MPA and mTORi group respectively, P = 0.277).

CONCLUSIONS

This single-center retrospective cohort analysis suggests that in hypersensitized kidney transplant recipients receiving tacrolimus-based immunosuppressive therapy similar clinical outcomes may be obtained using mTOR inhibitors compared to mycophenolate.

Hypertensive Cardiotoxicity in Cancer Treatment-Systematic Analysis of Adjunct, Conventional Chemotherapy, and Novel Therapies-Epidemiology, Incidence, and Pathophysiology

Cardiotoxicity is the umbrella term for cardiovascular side effects of cancer therapies. The most widely recognized phenotype is left ventricular dysfunction, but cardiotoxicity can manifest as arrhythmogenic, vascular, myocarditic and hypertensive toxicities. Hypertension has long been regarded as one of the most prevalent and modifiable cardiovascular risk factors in the general population, but its relevance during the cancer treatment journey may be underestimated. Hypertensive cardiotoxicity occurs de novo in a substantial proportion of treated cancer patients. The pathology is incompletely characterized—natriuresis and renin angiotensin system interactions play a role particularly in conventional treatments, but in novel therapies endothelial dysfunction and the interaction between the cancer and cardiac kinome are implicated. There exists a treatment paradox in that a significant hypertensive response not only mandates anti-hypertensive treatment, but in fact, in certain cancer treatment scenarios, hypertension is a predictor of cancer treatment efficacy and response. In this comprehensive review of over 80,000 patients, we explored the epidemiology, incidence, and mechanistic pathophysiology of hypertensive cardiotoxicity in adjunct, conventional chemotherapy, and novel cancer treatments. Conventional chemotherapy, adjunct treatments, and novel targeted therapies collectively caused new onset hypertension in 33–68% of treated patients. The incidence of hypertensive cardiotoxicity across twenty common novel therapies for any grade hypertension ranged from 4% (imatinib) to 68% (lenvatinib), and high grade 3 or 4 hypertension in <1% (imatinib) to 42% (lenvatinib). The weighted average effect was all-grade hypertension in 24% and grade 3 or 4 hypertension in 8%.

Optimization of tacrolimus in kidney transplantation: New pharmacokinetic perspectives

Tacrolimus is the cornerstone of immunosuppressive therapy after kidney transplantation (KT), but its use is complicated by a narrow therapeutic index and high inter- and intra-patient pharmacokinetic variability. There are three available oral formulations of tacrolimus: immediate-release tacrolimus (IR-Tac), extended-release tacrolimus (ER-Tac) and a MeltDose® (LCPT) formulation, the latter favoring a prolonged drug release and increased bioavailability. The time-concentration curves of these formulations are different. Compared with IR-Tac and ER-Tac, LCPT has a relatively flat pharmacokinetic profile with less fluctuation between trough and peak exposures, and a delayed peak concentration. This translates to a more stable delivery of tacrolimus and may alleviate the risk of underexposure and allograft rejection or overexposure and toxicity. The once-daily formulation of both ER-TAC and LCPT may also offer a potential advantage on patient adherence. Fast metabolizers of tacrolimus, the elderly, and human leukocyte antigen-sensitized patients are at risk of poorer outcomes after KT, possibly associated with a different exhibited pharmacokinetics of tacrolimus or different requirements in terms of exposure. Simple, practical strategies are needed to identify patients at risk of suboptimal KT outcomes and those who would benefit from a more proactively personalized approach to tacrolimus treatment. This review aims to increase awareness of the link between the pharmacokinetics of oral tacrolimus formulations and the clinical needs of patients after KT, particularly among those who have clinically significant pharmacokinetic variation of tacrolimus.

Long-Term Kidney Transplant Outcomes: Role of Prolonged-Release Tacrolimus

Tacrolimus has significantly improved outcomes for kidney transplant patients and remains the cornerstone of immunosuppressive therapy. While improvements in short-term outcomes in transplantation have been achieved in recent years, maintaining long-term graft survival remains a challenge in kidney transplantation. Minimizing risk factors for poor long-term kidney graft function and survival, and modifying tacrolimus regimens in the early and maintenance phases post-transplantation are essential to maintain long-term kidney transplant outcomes. Tacrolimus has a narrow therapeutic window, resulting in a tightly defined range of optimal drug exposure. Underimmunosuppression is associated with long-term risks, such as the development of donor-specific antibodies and antibody-mediated rejection, with a high possibility of a decline in kidney function and progression to graft failure. Conversely, prolonged overimmunosuppression carries a risk of drug-related adverse events. This review provides an overview of the differences in the formulation, delivery, and pharmacokinetic profiles between immediate- and prolonged-release tacrolimus and evaluates the effect of prolonged-release tacrolimus on the risk factors for poor outcomes in kidney transplantation. Recent evidence is used to provide guidance on target tacrolimus trough levels in the early and maintenance phases post-transplantation, with a view to improving long-term kidney graft function.

Preventive effect of early introduction of everolimus and reduced-exposure tacrolimus on renal interstitial fibrosis in de novo living-donor renal transplant recipients

BACKGROUND

To improve the long-term outcomes following renal transplantation, prevention of renal-allograft interstitial fibrosis (IF), mainly due to calcineurin inhibitors, is an important therapeutic target. Everolimus (EVR) was reported to have antifibrotic effects. We aimed to investigate the safety, efficacy, and IF of our modified immunosuppressive regimen, which includes early introduction of EVR and reduced-exposure tacrolimus (Tac) (EVR group), and compare it with the standard-exposure tacrolimus-based regimen (Tac group) in de novo living-donor renal recipients.

METHODS

In this retrospective, single-center cohort study, we compared the 2-year clinical courses between the two groups according to intention to treat. Additionally, in patients in whom biopsies were obtained at 1 h, 3 months, and 12 months post-transplant, we compared IF between the groups using imaging analysis.

RESULTS

Overall, 47 patients were included (EVR group, n = 22; Tac group, n = 25). There were no significant differences in renal function and incidences of rejection and viral infections between the groups at the 2-year post-transplant follow-up. However, pathologic imaging analysis (n = 34) revealed chronological progression of IF in the Tac group during the first year post-transplant and no changes in the EVR group (fibrosis rate at 3 months: 20.8 vs. 13.6%, p < 0.001; at 12 months: 24.7 vs. 14.7%, p < 0.001, respectively).

CONCLUSION

Our modified immunosuppressive regimen may have an antifibrotic effect on transplanted kidneys without loss of safety and efficacy.

Two-year outcomes in de novo renal transplant recipients receiving everolimus-facilitated calcineurin inhibitor reduction regimen from the TRANSFORM study

TRANSFORM (TRANSplant eFficacy and safety Outcomes with an eveRolimus-based regiMen) was a 24-month, prospective, open-label trial in 2037 de novo renal transplant recipients randomized (1:1) within 24 hours of transplantation to receive everolimus (EVR) with reduced-exposure calcineurin inhibitor (EVR + rCNI) or mycophenolate with standard-exposure CNI. Consistent with previously reported 12-month findings, noninferiority of the EVR + rCNI regimen for the primary endpoint of treated biopsy-proven acute rejection (tBPAR) or estimated glomerular filtration rate (eGFR) <50 mL/min per 1.73 m² was achieved at month 24 (47.9% vs 43.7%; difference = 4.2%; 95% confidence interval = -0.3, 8.7; P = .006). Mean eGFR was stable up to month 24 (52.6 vs 54.9 mL/min per 1.73 m² ) in both arms. The incidence of de novo donor-specific antibodies (dnDSA) was lower in the EVR + rCNI arm (12.3% vs 17.6%) among on-treatment patients. Although discontinuation rates due to adverse events were higher with EVR + rCNI (27.2% vs 15.0%), rates of cytomegalovirus (2.8% vs 13.5%) and BK virus (5.8% vs 10.3%) infections were lower. Cytomegalovirus infection rates were significantly lower with EVR + rCNI even in the D+/R- high-risk group (P < .0001). In conclusion, the EVR + rCNI regimen offers comparable efficacy and graft function with low tBPAR and dnDSA rates and significantly lower incidence of viral infections relative to standard-of-care up to 24 months. Clinicaltrials.gov number: NCT01950819.

Optimal dose of everolimus administered with tacrolimus in living donor kidney transplantation

Everolimus (EVR) is often administered with cyclosporine A (CsA), according to an established protocol. Although the administration protocol of EVR with tacrolimus (TAC) has not been established, it has been clinically demonstrated that a higher dose of EVR is necessary when used in combination with TAC than with CsA. In this study, we aimed to determine the optimal dose of EVR administered with TAC to maintain a similar EVR level in the blood to that observed when EVR is administered with CsA. Between June 2009 and January 2016, 22 patients who underwent living donor kidney transplantation were enrolled in this study. Among them, 12 patients were administered steroids, basiliximab, CsA, and EVR (CsA + EVR group) and 10 were administered steroids, basiliximab, TAC, and EVR (TAC + EVR group). Blood samples were collected at different time points from patients in both CsA + EVR and TAC + EVR groups, after drug administration. The trough EVR level in both groups was maintained within 3-8 ng/mL during the perioperative period. The optimal EVR doses for both groups were estimated by using a population pharmacokinetic analysis. Overall, the optimal dose of EVR for the TAC + EVR group was 3.59-fold higher than that for the CsA + EVR group to maintain a similar trough level to that of the latter group. Thus, administration of a higher EVR dose is recommended when provided in combination with TAC than with CsA to prevent adverse events caused by under immunosuppression, that could lead to acute kidney rejection.

Everolimus-based Immunosuppression Possibly Suppresses Mean Fluorescence Intensity Values of De Novo Donor-specific Antibodies After Primary Kidney Transplantation

PURPOSE

We evaluated de novo donor-specific antibody (DSA) production of everolimus (EVR)-based immunosuppression for primary kidney transplant recipients involved in the A1202 study at our institute.

METHODS

From March 2008 to August 2009, 24 recipients were prospectively randomized into 2 groups. The EVR group received reduced cyclosporin A and EVR. The standard protocol (STD) group received standard cyclosporin A and mycophenolate mofetil. Both groups received basiliximab and steroids. De novo DSA was identified using LABScreen single antigen beads (One Lambda, Canoga Park, Calif., United States). Mean fluorescence intensity (MFI) values > 1000 were considered positive. P < .05 was considered significant.

RESULTS

Graft survival was 100% in the EVR group and 90.9% in the STD group. All patients remained on the primary protocol in the EVR group, but 3 patients in the STD group (27.3%) were converted to tacrolimus due to DSA and non-adherence. Estimated glomerular filtration rate was similar in both groups. No EVR group recipients and 9.1% of STD group recipients were treated for T-cell-mediated rejection. No recipients of the EVR group exhibited peritubular capillaritis, while 9.1% in STD group developed chronic active antibody-mediated rejection. LABScreen revealed an accumulative class II DSA production rate of 15.4% in the EVR group and 18.3% in the STD group at 10 years. When the MFI cut-off level was set to 6000, anti-HLA antibody and de novo DSA-free survival was significantly better in the EVR group.

CONCLUSIONS

EVR-based immunosuppression provided equivalent or even better clinical outcomes. EVR suppressed de novo DSA production at 10 years follow-up; however, further follow-up is inevitable.

An open-label, randomized trial indicates that everolimus with tacrolimus or cyclosporine is comparable to standard immunosuppression in de novo kidney transplant patients

This is a randomized trial (ATHENA study) in de novo kidney transplant patients to compare everolimus versus mycophenolic acid (MPA) with similar tacrolimus exposure in both groups, or everolimus with concomitant tacrolimus or cyclosporine (CsA), in an unselected population. In this 12-month, multicenter, open-label study, de novo kidney transplant recipients were randomized to everolimus with tacrolimus (EVR/TAC), everolimus with CsA (EVR/CsA) or MPA with tacrolimus (MPA/TAC), with similar tacrolimus exposure in both groups. Non-inferiority of the primary end point (estimated glomerular filtration rate [eGFR] at month 12), assessed in the per-protocol population of 338 patients, was not shown for EVR/TAC or EVR/CsA versus MPA/TAC. In 123 patients with TAC levels within the protocol-specified range, eGFR outcomes were comparable between groups. The mean increase in eGFR during months 1 to 12 post-transplant, analyzed post hoc, was similar with EVR/TAC or EVR/CsA versus MPA/TAC. The incidence of treatment failure (biopsy proven acute rejection, graft loss or death) was not significant for EVR/TAC but significant for EVR/CsA versus MPA/TAC. Most biopsy-proven acute rejection events in this study were graded mild (BANFF IA). There were no differences in proteinuria between groups. Cytomegalovirus and BK virus infection were significantly more frequent with MPA/TAC. Thus, everolimus with TAC or CsA showed comparable efficacy to MPA/TAC in de novo kidney transplant patients. Non-inferiority of renal function, when pre-specified, was not shown, but the mean increase in eGFR from month 1 to 12 was comparable to MPA/TAC.

Low early posttransplant serum tacrolimus levels are associated with poor patient survival in lung transplant patients

BACKGROUND:

Low-dose tacrolimus-based immunosuppression is a standard therapy in kidney and liver transplantation; however, the optimal therapeutic level of tacrolimus has not been established in lung transplantation. We aimed to identify the tacrolimus level associated with better outcomes in lung transplant patients.

METHODS:

This retrospective study included patients who underwent lung transplantation at Seoul National University Hospital between 2006 and 2016. Kaplan–Meier survival analysis and Cox regression were performed according to tacrolimus levels at several time-points within 1-year posttransplantation.

RESULTS:

A total of 43 patients received bilateral lung transplantation. The median age was 53 years and the median follow-up was 20.5 months. Overall and 1-year patient survival rates were 55.8% and 74.4%, respectively. Infection was the most common cause of death (78.9%). Chronic lung allograft dysfunction was observed in 16.3%. A tacrolimus level <9 ng/ml at 1 month was associated with lower rejection-free survival (P = 0.009). A time-averaged tacrolimus level <10 ng/ml within 1 month posttransplantation was an independent risk factor for poor patient survival (hazard ratio: 4.904; 95% confidence interval: 1.930–12.459; P= 0.001). Furthermore, higher tacrolimus levels did not increase infectious complications.

CONCLUSIONS:

These finding suggest that tacrolimus levels ≥10 ng/ml within 1 month after lung transplantation appear to be associated with better patient survival.

Therapeutic Use of mTOR Inhibitors in Renal Diseases: Advances, Drawbacks, and Challenges

The mammalian (or mechanistic) target of rapamycin (mTOR) pathway has a key role in the regulation of a variety of biological processes pivotal for cellular life, aging, and death. Impaired activity of mTOR complexes (mTORC1/mTORC2), particularly mTORC1 overactivation, has been implicated in a plethora of age-related disorders, including human renal diseases. Since the discovery of rapamycin (or sirolimus), more than four decades ago, advances in our understanding of how mTOR participates in renal physiological and pathological mechanisms have grown exponentially, due to both preclinical studies in animal models with genetic modification of some mTOR components as well as due to evidence coming from the clinical experience. The main clinical indication of rapamycin is as immunosuppressive therapy for the prevention of allograft rejection, namely, in renal transplantation. However, considering the central participation of mTOR in the pathogenesis of other renal disorders, the use of rapamycin and its analogs meanwhile developed (rapalogues) everolimus and temsirolimus has been viewed as a promising pharmacological strategy. This article critically reviews the use of mTOR inhibitors in renal diseases. Firstly, we briefly overview the mTOR components and signaling as well as the pharmacological armamentarium targeting the mTOR pathway currently available or in the research and development stages. Thereafter, we revisit the mTOR pathway in renal physiology to conclude with the advances, drawbacks, and challenges regarding the use of mTOR inhibitors, in a translational perspective, in four classes of renal diseases: kidney transplantation, polycystic kidney diseases, renal carcinomas, and diabetic nephropathy.

Pilot Conversion Study From Mycophenolate Mofetil to Everolimus in Stable ABO-Incompatible Kidney Transplant Recipients: Analysis of 1-Year Follow-Up Data

OBJECTIVES

Here, we report our 1-year follow-up data of stable ABO-incompatible kidney transplant recipients who converted from mycophenolate mofetil plus a standard dose of a calcineurin inhibitor to everolimus plus low exposure to calcineurin inhibitors.

MATERIALS AND METHODS

Our study included 17 recipients of ABO-incompatible kidney transplant procedures performed at our institution. At baseline and at 3 and 12 months after conversion, graft biopsies were performed to check for acute rejection and C4d deposition.

RESULTS

Treatment with everolimus was stopped due to adverse events in 8 patients (47.1%). Conversion to everolimus with calcineurin inhibitor minimization did not induce acute rejection or C4d deposition at 3 and 12 months after conversion in ABO-incompatible kidney transplant recipients in whom everolimus was maintained or stopped within 1 year after conversion.

CONCLUSIONS

Everolimus elicited no acute rejection and no C4d deposition, whether everolimus was maintained or stopped within 1 year after conversion, in ABO-incompatible kidney transplant recipients.

The impact of everolimus in reducing cytomegalovirus events in kidney transplant recipients on steroid-avoidance strategy: 3-year follow-up of a randomized clinical trial

There is no evidence of whether everolimus (EVR) reduces cytomegalovirus (CMV) events in patients receiving steroid-free regimens. Besides, studies evaluating a tacrolimus (TAC) and EVR regimen are limited to 1-year follow-up. In this single-center prospective randomized trial, the incidence of CMV and 3-year efficacy and safety outcomes of EVR were compared to those of mycophenolate sodium (MPS) in a steroid-free regimen based on low-exposure TAC. Both groups received rabbit anti-thymocyte globulin (r-ATG) induction (6 mg/kg) and the steroids were withdrawn at day 7. Maintenance immunosuppression consisted of TAC (4-7 ng/ml until month 3 and 2-4 ng/ml thereafter) plus EVR (3-8 ng/ml) in the EVR group (n = 59); and TAC (4-7 ng/ml during all follow-up) plus MPS (1440 mg) in the MPS group (n = 56). The EVR group presented with a lower incidence of CMV events (18.6% vs. 50%, P = 0.001). No differences were observed in biopsy-proven acute rejection (6.8% vs. 3.6%, P = 0.680),graft loss (0.0% vs. 1.8%, P = 0.487),death (6.8% vs. 1.8%, P = 0.365), or estimated glomerular filtration rate at 36 months (61.1 ± 25.4 vs. 66.3 ± 24 ml/min/1.73 m² , P = 0.369). A higher proportion of patients discontinued MPS treatment (8.5% vs. 26.8%, P = 0.013) for safety issues. In conclusion, EVR was associated with lower rates of CMV events in patients induced with standard dose r-ATG and a maintenance steroid-free regimen based on TAC. This regimen effectively prevented acute rejection and demonstrated a more favorable safety profile. (ClinicalTrials.gov:NCT02084446).

Everolimus with Reduced Calcineurin Inhibitor Exposure in Renal Transplantation

Background Everolimus permits reduced calcineurin inhibitor (CNI) exposure, but the efficacy and safety outcomes of this treatment after kidney transplant require confirmation.Methods In a multicenter noninferiority trial, we randomized 2037 de novo kidney transplant recipients to receive, in combination with induction therapy and corticosteroids, everolimus with reduced-exposure CNI (everolimus arm) or mycophenolic acid (MPA) with standard-exposure CNI (MPA arm). The primary end point was treated biopsy-proven acute rejection or eGFR<50 ml/min per 1.73 m² at post-transplant month 12 using a 10% noninferiority margin.Results In the intent-to-treat population (everolimus n=1022, MPA n=1015), the primary end point incidence was 48.2% (493) with everolimus and 45.1% (457) with MPA (difference 3.2%; 95% confidence interval, -1.3% to 7.6%). Similar between-treatment differences in incidence were observed in the subgroups of patients who received tacrolimus or cyclosporine. Treated biopsy-proven acute rejection, graft loss, or death at post-transplant month 12 occurred in 14.9% and 12.5% of patients treated with everolimus and MPA, respectively (difference 2.3%; 95% confidence interval, -1.7% to 6.4%). De novo donor-specific antibody incidence at 12 months and antibody-mediated rejection rate did not differ between arms. Cytomegalovirus (3.6% versus 13.3%) and BK virus infections (4.3% versus 8.0%) were less frequent in the everolimus arm than in the MPA arm. Overall, 23.0% and 11.9% of patients treated with everolimus and MPA, respectively, discontinued the study drug because of adverse events.Conclusions In kidney transplant recipients at mild-to-moderate immunologic risk, everolimus was noninferior to MPA for a binary composite end point assessing immunosuppressive efficacy and preservation of graft function.

Evaluation of the 1000 renal transplants carried out at the University Hospital of the Botucatu Medical School (HCFMB) - UNESP and their evolution over the years

INTRODUCTION

The progress in kidney transplantation has been evident over the years, as well as its benefits for patients.

OBJECTIVES

To evaluate the 1.000 kidney transplants performed at the Botucatu Medical School University Hospital, subdividing the patients in different periods, according to the current immunosuppression, and evaluating the differences in graft and patient survival.

METHODS

Retrospective cohort analysis of the transplants performed between 06/17/87 to 07/31/16, totaling 1,046 transplants, subdivided into four different periods: 1) 1987 to 2000: cyclosporine with azathioprine; 2) 2001 to 2006: cyclosporine with mycophenolate; 3) 2007 to 2014: tacrolimus with antimetabolic; and 4) 2015 to 2016: tacrolimus with antimetabolic, with increased use of the combination of tacrolimus and mTOR inhibitors.

RESULTS

There was an increase in the mean age of recipients and increase in deceased donors and their age in the last two periods. There was a reduction in graft function delay, being 54.3% in the fourth period, compared to 78.8% in the first, p = 0.002. We found a reduction in acute rejection, being 6.1% in the last period compared to 36.3% in the first, p = 0.001. Urological complications and diabetes after transplantation were more frequent in the first two periods. The rates of cytomegalovirus infection were higher in the last two periods. There was an improvement in graft survival, p = 0.003. There was no difference in patient survival, p = 0.77 (Figure 2).

CONCLUSION

There was a significant increase in the number of transplants, with evolution in graft survival, despite the worsening in the profiles of recipients and donors.

Prediction of Tacrolimus Exposure by CYP3A5 Genotype and Exposure of Co-Administered Everolimus in Japanese Renal Transplant Recipients

While tacrolimus and everolimus have common metabolic pathways through CYP3A4/5, tacrolimus is metabolized solely by CYP3A4 in recipients with the CYP3A5*3/*3. The purpose of this study was to evaluate how the area under the blood concentration-time curves (AUC) of tacrolimus could be predicted based on CYP3A5 genotype and the AUC of everolimus in renal transplant patients taking both drugs. The dose-adjusted AUC (AUC/D) of tacrolimus and everolimus were calculated at one month and one year after transplantation. Significant correlations between the AUC/D of tacrolimus and everolimus were found for patients with the CYP3A5*1 allele or CYP3A5*3/*3 at both one month and one year. At both stages, the determination coefficients were higher and the slopes of regression equations were larger for patients with CYP3A5*3/*3 compared to the CYP3A5*1 allele. A good correlation between single doses of tacrolimus and everolimus was found for CYP3A5*3/*3 patients at 1 year after transplantation (r = 0.794, p < 0.001). The variability of the AUC_0–24/D of tacrolimus for each CYP3A5 genotype could be predicted based on the AUC_0–12/D of everolimus. Clinicians may be able to comprehensively carry out the dose adjustments of tacrolimus and everolimus based on relationship with AUCs of both drugs in each CYP3A5 genotype.

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.

De Novo Donor-Specific Antibody Formation in Tacrolimus-Based, Mycophenolate Versus Mammalian Target of Rapamycin Immunosuppressive Regimens

OBJECTIVES

De novo donor-specific antibody formation posttransplant is associated with decreased graft survival. It is not known whether mammalian target of rapamycin inhibitors may be advantageous or detrimental compared with mycophenolate in the prevention of de novo donor-specific antibody formation.

MATERIALS AND METHODS

We compared 66 kidney and kidney-pancreas transplant recipients who received tacrolimus, mammalian target of rapamycin inhibitor, and prednisone (group 1; 36 of whom received everolimus and 30 of whom received sirolimus) versus 132 patients who received tacrolimus, mycophenolate, and prednisone (group 2) matched for age, sex, race, and type/timing of transplant from 2007 to 2012.

RESULTS

Rates of de novo donor-specific antibody formation were comparable between groups at 1, 6, and 12 months (16.7%, 25.8%, and 28.8% for group 1 vs 9.8%, 15.2%, and 22.0% for group 2). There were no significant differences in class (I, II, or mixed), strength (mean fluorescence intensity) of de novo donor-specific antibody, glomerular filtration rate, proteinuria levels, or acute rejection between the groups. In those with de novo donor-specific antibody by 6 months, acute rejection was more common versus those without de novo donor-specific antibody formation (24.3% vs 5.6% at 6 mo; P = .002), with rates of 27.0% versus 6.8% at 1 year (P = .001) and 40.7% versus 11.3% at 2 years (P < .001). An associated reduction in glomerular filtration rate also occurred.

CONCLUSIONS

Mammalian target of rapamycin inhibitors were neither protective nor permissive for de novo donor-specific antibody formation versus mycophenolate when used with clinically relevant tacrolimus dosing regimens.

Adequacy of Initial Everolimus Dose, With and Without Calcineurin Inhibitors, in Kidney Transplant Recipients

BACKGROUND

This study investigates the adequacy of initial everolimus (EVR) dose, with and without calcineurin inhibitors (CNI), in kidney transplant recipients.

METHODS

This retrospective cohort analysis involved data from 305 kidney transplant recipients participating in 3 randomized trials receiving reduced dose cyclosporin A (CsA) combined with EVR 0.75 mg BID (CSA/EVR0.75, N = 32) or 1.5 mg BID (CSA/EVR1.5, N = 31), reduced dose tacrolimus (TAC) combined with EVR 1.5 mg BID (TAC0.05/EVR1.5, N = 83), standard dose TAC combined with EVR 1.5 mg BID (TAC0.1/EVR1.5, N = 93), and EVR 1.5 mg BID (EVR1.5, N = 66) with TAC introduction after day 5. The adequacy of the initial EVR dose, based on EVR whole blood trough between 3 and 8 ng/mL, was compared using first EVR blood concentrations obtained at day 3 after transplantation.

RESULTS

Recipient age, proportion of patients with diabetes mellitus, and proportion of grafts from living donors were different among the groups. Dose-corrected EVR concentrations were higher in patients receiving CsA than in those receiving TAC or no calcineurin inhibitors (6.7 ± 5.9 versus 5.4 ± 2.2 versus 2.4 ± 0.8 versus 2.5 ± 0.9 versus 2.2 ± 0.7, P = 0.000). No differences were observed comparing dose adjusted EVR concentrations combined with TAC or alone (P = 0.073). The proportion of patients with EVR concentration below <3 ng/mL was lower when EVR was combined with CsA (25 versus 3 versus 43 versus 33 versus 50%, P = 0.000). Later introduction of TAC did not influence EVR concentrations. There were no differences in mean CsA concentrations comparing patients receiving EVR 0.75 or 1.5 mg BID (240 ± 143 versus 213 ± 105 ng/mL). On the other hand, mean TAC concentrations were higher according to the initial TAC dose regimen (6.4 ± 3.9 versus 9.8 ± 5.9 ng/mL).

CONCLUSIONS

In de novo kidney transplant recipients, the choice of the initial dose of EVR should consider the type of calcineurin inhibitor to reach target EVR concentration within the first week in a higher proportion of patients, maximizing the efficacy/toxicity profile.

Overview of Immunosuppressive Therapy in Solid Organ Transplantation

Mechanisms of rejection, new pharmacologic approaches, and genomic medicine are major foci for current research in transplantation. It is hoped that these new agents and personalized immunosuppression will provide for less toxic regimens that are effective in preventing both acute and chronic allograft rejection. Until new agents are available, practitioners must use various combinations of currently approved agents to find the best regimens for improved long-term outcomes.

Longitudinal Pharmacokinetics of Everolimus When Combined With Low-level of Tacrolimus in Elderly Renal Transplant Recipients

BACKGROUND

Although the proportion of elderly patients among renal transplant recipients has increased, pharmacokinetic (PK) studies of immunosuppressants rarely include older patients.

METHODS

We studied 12-hour everolimus (EVL) PK in 16 elderly renal transplant recipients (all whites; 10 men; mean age, 64 ± 2 years (61-71 years), in 4 separate timepoints (at 7, 30, 60, and 150 days) after EVL introduction, corresponding to a mean postrenal transplantation day: PK1 (43 ± 4 days), PK2 (65 ± 7 days), PK3 (106 ± 17 days), and PK4 (206 ± 40 days). Patients received EVL (target trough level (Ctrough, 3-8 ng/mL), prednisone, and tacrolimus (TCL) (target Ctrough, 2-5 ng/mL).

RESULTS

Mean TCL-Ctrough was 7.2 ± 3.8, 4.9 ± 2.2, 4.9 ± 2.2, and 4.5 ± 1.2 ng/mL at PK1, PK2, PK3, and PK4, respectively. There were no differences among timepoints for mean EVL daily dose (data shown as PK3) (3.5 ± 1.3 mg/d), Ctrough (4.7 ± 2.5 ng/mL), AUC0-12h (106 ± 51 ng/h per mL), Caverage (8.8 ± 4.2 ng/mL), Cmax (19.2 ± 9.7 ng/mL), apparent Half-life (11.7 ± 4.2 hours), estimated total body clearance (0.39 ± 0.27 L/h), or fluctuation (166 ± 65%). Also, none of those PK parameters differed statistically when adjusted for body weight. EVL-Ctrough showed a very high correlation (r = 0.849) with AUC0-12h.

CONCLUSIONS

Our data indicate that elderly renal transplant recipients starting EVL 1 month after transplantation along with a steady-state TCL level, present stable EVL-PK parameters without significant changes in dose or exposure during the first 6 months after renal transplantation.

Association of Clinical Events With Everolimus Exposure in Kidney Transplant Patients Receiving Low Doses of Tacrolimus

A key objective in the use of immunosuppression after kidney transplantation is to attain the optimal balance between efficacy and safety. In a phase 3b, multicenter, randomized, open-label, noninferiority study, the incidences of clinical events, renal dysfunction, and adverse events (AEs) were analyzed at 12 months in 309 de novo renal transplant recipients receiving everolimus (EVR), low-dose tacrolimus (LTac), and prednisone. Cox proportional hazard regression modeling was used to estimate the probability of clinical events at specified combinations of time-normalized EVR and Tac trough concentrations. At 12 months, the highest incidence of treated biopsy-proven acute rejection (tBPAR) and graft loss occurred most often in patients with EVR trough concentration <3 ng/mL (64.7% and 10.5%, respectively). At 1 month and 12 months, increasing EVR levels were associated with fewer tBPAR events (both p < 0.0001). Low estimated glomerular filtration rate (eGFR) and decreased eGFR occurred more often in patients with lower EVR and higher Tac levels. AEs were most often observed in patients with EVR levels <3 ng/mL. This study supports maintaining an EVR trough concentration of 3-8 ng/mL, when combined with LTac, to achieve balanced efficacy and safety in renal transplant recipients.

TRIAL REGISTRATION

NCT01025817.

Longitudinal Pharmacokinetics of Tacrolimus in Elderly Compared With Younger Recipients in the First 6 Months After Renal Transplantation

BACKGROUND

Elderly (Eld) (≥60 years) recipients are receiving renal transplants more frequently. The pharmacokinetics (PK) studies of immunosuppressive drugs in healthy volunteers, rarely, include old patients.

METHODS

We studied 208 12-hour tacrolimus (TAC) PK (0, 20, 40, 60, 90, 120, 180, 240, 360, 480, 600, 720 min) in 44 Eld (65 ± 3 years) and compared the results with 31 younger controls (Ctrl) (35 ± 6 years) recipients, taking oral TAC/mycophenolate sodium (MPS)/prednisone, at 4 different timepoints: PK1 (8 ± 2 days; n = 72), PK2 (31 ± 4 days; n = 61), PK3 (63 ± 6 days; n = 44), and PK4 (185 ± 10 days; n = 31). Tacrolimus PK was measured by ultraperformance liquid chromatography coupled to a mass spectrometer repetition and noncompartmental PKs were analyzed using Phoenix WinNonlin.

RESULTS

Mean TAC dose was lower in the Eld group than in Ctrl ones throughout timepoints either by total daily dose or adjusted (Adj) per body weight. Mean TAC trough level (Cmin), used to adjust daily dose, was not different between the 2 groups in all timepoints. AdjCmax and AdjTAC-area under the curve at dosing interval were both higher in the Eld compared to the Ctrl group in PKs1, 3, and 4. Estimated total body clearance normalized by dose and weight was lower in the Eld group compared with the Ctrl in all PKs and statistically lower at PKs 1 and 3. Similar to younger recipients TAC trough level has also a high correlation (R = 0.76) with area under the curve at dosing interval.

CONCLUSIONS

These data indicate that Eld recipients have a lower TAC clearance and therefore need a lower TAC dose than younger recipients.

Recommendations of everolimus use in liver transplant

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

Limitations of the interpretation and extrapolation of clinical trial data in kidney transplant recipients

OBJECTIVE

The risks and benefits of the participation of kidney transplant recipients in randomized clinical trials (RCTs) investigating new immunosuppressive therapies are unknown.

DESIGN AND SETTING

We included patients from 12 prospective phase II/III RCTs randomized to the experimental (G1, n=319) or standard-of-care internal control group (G2, n=118). We constructed two additional external control groups with (G3, n=319) or without (G4, n=319) matching inclusion/exclusion criteria based on transplant date. The primary outcome analysis was the composite clinical efficacy failure, defined as biopsy-proven acute rejection (BPAR), graft loss, death, or loss to follow-up 12 months after kidney transplantation.

RESULTS

Survival free of composite clinical efficacy failure was higher among participants in RCT, without difference between experimental or standard-of-care therapy (80∙3 vs 78∙0 vs 69∙9 vs 66∙1%, P<.001), respectively. Patient (98.1 vs 99.2 vs 96.9 vs 91.8 P<.001) and graft (94.0 vs 98.3 vs 90.9 vs 82.4) survivals were also higher in G1 compared to G4, but no differences in survival free of BPAR were observed (85.3 vs 78.8 vs 82.8 vs 81.2 P>.05), respectively.

CONCLUSION

These findings suggested that new treatments investigated in kidney transplant recipients are not associated with detectable harm compared to standard of care.

Donor-Specific Anti-Human Leukocyte Antigens Antibodies, Acute Rejection, Renal Function, and Histology in Kidney Transplant Recipients Receiving Tacrolimus and Everolimus

BACKGROUND

This analysis compared efficacy, renal function, and histology in kidney transplant recipients receiving tacrolimus (TAC) combined with everolimus (EVR) or mycophenolate (MPS).

METHODS

This was a retrospective analysis from a randomized trial in kidney transplant recipients who received a single 3 mg/kg dose of rabbit antithymocyte globulin (r-ATG), TAC, EVR, and prednisone (PRED; r-ATG/EVR, n = 85), basiliximab (BAS), TAC, EVR, and PRED (BAS/EVR, n = 102) or BAS, TAC, MPS, and PRED (BAS/MPS, n = 101). We evaluated the incidence of de novo donor-specific anti-human leukocyte antigens antibodies (DSA) and histology on protocol biopsies at 12 months, and the incidence of acute rejection, estimated glomerular filtration rate (eGFR) and proteinuria at 36 months.

RESULTS

At 12 months, there were no differences in de novo DSA (6.4 vs. 3.4 vs. 5.5%) or in subclinical inflammation (2.0 vs. 4.8 vs. 10.2%), interstitial fibrosis/tubular atrophy (57.1 vs. 58.5 vs. 53.8%) and C4d deposition (2.0 vs. 7.3 vs. 2.6%). At 36 months, there were no differences in the incidence of treatment failure (19.0 vs. 27.7 vs. 27.7%, p = 0.186), first biopsy-proven acute rejection (9.5 vs. 21.8 vs. 16.8%, p = 0.073), and urine protein/creatinine ratios (0.53 ± 1.05 vs. 0.62 ± 0.75 vs. 0.71 ± 1.24). eGFR was lower in the BAS/EVR compared to that in the BAS/MPS group (53.4 ± 20.9 vs. 50.8 ± 19.5 vs. 60.7 ± 21.2 mL/min/1.73 m2, p = 0.017) but comparable using a sensitive analysis (49.5 ± 23 vs. 47.5 ± 22.6 vs. 53.6 ± 27.8 mL/min/1.73 m2, p = 0.207).

CONCLUSION

In this cohort, the use of EVR and reduced TAC concentrations were associated with comparable efficacy, renal function, and histological parameters compared to the standard-of-care immunosuppressive regimen.

Glomerular Diseases and Renal Transplantation: Pathogenic Pathways and Evolution of Therapeutic Interventions

Glomerular diseases and renal transplantation are the main fields of nephrology in which the immune system plays a prevalent role. Glomerular diseases have traditionally been attributed to auto-immune conditions, whereas allograft rejection has been considered an allo-immune response. However, common immunopathologic mechanisms that include Toll-like receptors, complement and B-cell activation, as well as genetic and infectious factors appear to be involved in the pathogenesis of both entities. Novel therapeutic regimens directed against specific targets of the immune system show promising results in glomerulopathies as well as in renal transplantation.

Efficacy and Safety of Everolimus Plus Low-Dose Tacrolimus Versus Mycophenolate Mofetil Plus Standard-Dose Tacrolimus in De Novo Renal Transplant Recipients: 12-Month Data

In this 12-month, multicenter, randomized, open-label, noninferiority study, de novo renal transplant recipients (RTxRs) were randomized (1:1) to receive everolimus plus low-dose tacrolimus (EVR+LTac) or mycophenolate mofetil plus standard-dose Tac (MMF+STac) with induction therapy (basiliximab or rabbit anti-thymocyte globulin). Noninferiority of composite efficacy failure rate (treated biopsy-proven acute rejection [tBPAR]/graft loss/death/loss to follow-up) in EVR+LTac versus MMF+STac was missed by 1.4%, considering the noninferiority margin of 10% (24.6% vs. 20.4%; 4.2% [-3.0, 11.4]). Incidence of tBPAR (19.1% vs. 11.2%; p < 0.05) was significantly higher, while graft loss (1.3% vs. 3.9%; p < 0.05) and composite of graft loss/death/lost to follow-up (6.1% vs. 10.5%, p = 0.05) were significantly lower in EVR+LTac versus MMF+STac groups, respectively. Mean estimated glomerular filtration rate was similar between EVR+LTac and MMF+STac groups (63.1 [22.0] vs. 63.1 [19.5] mL/min/1.73 m² ) and safety was comparable. In conclusion, EVR+LTac missed noninferiority versus MMF+STac based on the 10% noninferiority margin. Further studies evaluating optimal immunosuppression for improved efficacy will guide appropriate dosing and target levels of EVR and LTac in RTxRs.

Immunosuppression Modification by Everolimus With Minimization of Calcineurin Inhibitors Recovers Kidney Graft Function Even in Patients With Very Late Conversion and Also With Poor Graft Function

BACKGROUND

Although kidney graft survival within 5 years after transplantation is now achieved in >95% of recipients, chronic graft deterioration remains a factor limiting long-term survival. Chronic nephrotoxicity induced by calcineurin inhibitors (CNIs) is one of the major causes of chronic graft injury; thus, minimization of CNIs by administration of everolimus (EVR) is expected to relieve their toxic effects.

METHODS

Fifty-six kidney transplant recipients receiving CNI-based immunosuppression (tacrolimus, n = 34; cyclosporine, n = 22) were analyzed. The average posttransplant period at conversion was 7.4 years and no less than 3 years. Conversion of immunosuppression was accomplished by reducing CNI by 40% in dose and beginning EVR at 1 or 1.5 mg. Changes in graft function were examined, and adverse effects were evaluated.

RESULTS

Significant improvement in graft function was observed quickly after EVR administration, and it had persisted for 1 year after conversion as a 7% increase in estimated glomerular filtration rate. No obvious acute rejection was observed. Further analyses concerning "timing of EVR conversion" and "graft function at conversion" were performed. Graft function was significantly improved even in patients with late conversion at 2 to 10 years. The estimated glomerular filtration rate was significantly improved even in patients with poor function.

CONCLUSIONS

We concluded that this modification to the immunosuppressive regimen, as expected, reduced CNI nephrotoxicity. Our results showed that even patients with very late conversion or poor graft function also benefited from EVR conversion with CNI minimization.

A Systematic Literature Review Approach to Estimate the Therapeutic Index of Selected Immunosuppressant Drugs After Renal Transplantation

BACKGROUND

Drugs that exhibit close margins between therapeutic and toxic blood concentrations are considered to have a narrow therapeutic index (NTI). The Food and Drug Administration has proposed that NTI drugs should have more stringent bioequivalence standards for approval of generic formulations. However, many immunosuppressant drugs do not have a well-defined therapeutic index (TI).

METHODS

We sought to determine whether safety, efficacy, and pharmacokinetic data obtained from the medical literature through a comprehensive literature search could be used to estimate the TI of cyclosporine, tacrolimus, and sirolimus. In this analysis, we considered TI ≤2 as a criterion to define a drug as having an NTI.

RESULTS

Published literature indicates that cyclosporine has a TI of 2-3, which falls just short of our criteria to be classified as having an NTI. We found sirolimus and tacrolimus to have a therapeutic range of 5-12 ng/mL and of 5-20 ng/mL, respectively, but were unable to calculate the TI.

CONCLUSIONS

Although the current literature does not provide a clear indication that these drugs have an NTI, the routine use of therapeutic drug monitoring in clinical practice suggests that more stringent testing of their pharmacokinetic and pharmacodynamic properties should be performed before the approval of generic formulations.

The risk of cancer in kidney transplant recipients may be reduced in those maintained on everolimus and reduced cyclosporine

Kidney transplant recipients are at a high risk of developing cancers after transplantation. Switching from calcineurin inhibitors to sirolimus has been shown to prevent secondary nonmelanoma skin cancer but whether everolimus with reduced exposure to calcineurin inhibitors has similar anti-cancer effects remains unknown. Therefore, we compared the risk of incident cancer over seven years of follow-up among kidney transplant recipients randomized to everolimus plus reduced exposure cyclosporine versus mycophenolate sodium and standard exposure cyclosporine. Using the Australian and New Zealand Dialysis and Transplant Registry (ANZDATA), we assessed the seven-year risk of incident cancer and other graft outcomes among a subgroup of recipients who had participated in the A2309 study using adjusted Cox proportional hazard models. Of 95 recipients, 66 were randomized to everolimus (1.5 mg or 3 mg) with reduced cyclosporine and 29 received mycophenolate sodium and standard exposure cyclosporine. Compared to mycophenolate sodium and standard exposure cyclosporine, everolimus treatment was associated with unadjusted hazard ratios of 0.28 (95% confidence interval 0.11-0.74), 0.39 (0.16-0.98) and 0.41 (0.23-0.71), respectively for nonmelanoma skin cancer, non-skin cancers and any cancers. Interestingly, the adjusted hazard ratios were 0.34 (0.13-0.91), 0.35 (0.09-1.25) and 0.32 (0.15-0.71), respectively. There was no association between treatment groups and rejection, graft loss or death. Compared to standard-exposure cyclosporine, everolimus with reduced exposure to cyclosporine may be associated with a reduced risk of cancer, particularly for non-melanoma skin cancer. Thus, if confirmed in larger patient cohorts, de novo use of everolimus with reduced exposure to calcineurin inhibitors may enable a reduction in cancer burden after transplantation.