Therapeutic Drug Monitoring for Everolimus in Heart Transplant Recipients Based on Exposure–Effect Modeling

Everolimus, a proliferation signal inhibitor, is an immunosuppressant that targets the primary causes of progressive allograft dysfunction, thus improving the long-term outcome after heart transplantation. The present study investigated whether therapeutic drug monitoring (TDM) of everolimus would benefit heart transplant patients. Data from a twelve-month phase III trial comparing everolimus (1.5 or 3 mg daily) with azathioprine were used to evaluate everolimus pharmacokinetics, exposure-efficacy/safety and TDM prognostic simulations. Everolimus trough levels were stable in the first year post-transplant and averaged 5.2 +/- 3.8 and 9.4 +/- 6.3 ng/mL in patients treated with 1.5 and 3 mg/day, respectively. Cyclosporine trough levels were similar in all treatment groups. Biopsy-proven acute rejection (BPAR) was reduced with everolimus trough levels > or =3 ng/mL. Intravascular ultrasound (IVUS) analysis showed evidence of reduced vasculopathy at 12 months with increasing everolimus exposure. Unlike cyclosporine, increasing everolimus exposure was not related to a higher rate of renal dysfunction. The TDM simulation, which was based on two everolimus dose adjustments and an initial starting dose of 1.5 mg/day, showed that the simulated BPAR rate (with TDM) was 21% versus 26% in the group with fixed dosing. Therefore, TDM in heart transplantation could optimize immunosuppressive efficacy and reduce treatment-related toxicity.     

Sotrastaurin,a Novel Small Molecule Inhibiting Protein Kinase C: First Clinical Results in Renal‐Transplant Recipients

Sotrastaurin, a novel protein‐kinase‐C inhibitor, blocks early T‐cell activation. In this 12‐month, Phase II study, de novo renal‐transplant patients were randomized to sotrastaurin (200 mg b.i.d.) + standard‐exposure tacrolimus (SET) or reduced‐exposure tacrolimus (RET) (SET: n = 76; RET: n = 66), or control (SET + mycophenolic acid [MPA, 720 mg b.i.d.]; n = 74). In both sotrastaurin groups, patients were converted from tacrolimus to MPA after Month 3, achieving calcineurin inhibitor‐free immunosuppression. The primary endpoint was composite efficacy failure (treated biopsy‐proven acute rejection, graft loss, death or loss to follow‐up). The key secondary endpoint was glomerular filtration rate (GFR). Composite efficacy failure rates were: 4.1%, 5.4% and 1.5% at Month 3 (preconversion) and 7.8%, 44.8% and 34.1% at study end in the control, sotrastaurin + SET and sotrastaurin + RET groups, respectively; these results led to premature study discontinuation. Median GFR at Month 6 was: 57.0, 53.0 and 60.0 mL/min/1.73 m², respectively. Study‐drug discontinuations due to adverse events occurred in 16.2%, 18.4% and 12.1%, respectively. Leukopenia and neutropenia occurred more frequently preconversion in control versus sotrastaurin groups: 13.7%, 5.6%, and 4.6%; and 11.1%, 4.3% and 3.1%, respectively. The initial sotrastaurin + tacrolimus regimen was efficacious and well tolerated but the postconversion sotrastaurin + MPA regimen showed inadequate efficacy. Longer‐term evaluation of sotrastaurin + tacrolimus is warranted.     

Everolimus with Optimized Cyclosporine Dosing in Renal Transplant Recipients: 6-Month Safety and Efficacy Results of Two Randomized Studies

Two prospective, randomized studies evaluated everolimus 1.5 vs. 3 mg/day with steroids and low-exposure cyclosporine (CsA) (C2 monitoring) in de novo renal transplant patients. Everolimus dosing was adjusted to maintain a minimum trough level of 3 ng/mL. Study 1 (A2306; n=237) had no induction therapy; in Study 2 (A2307; n=256) basiliximab was administered (Days 0 and 4). The primary endpoint was renal function at 6 months. CsA C2 target levels, initially 1200 ng/mL in Study 1 and 600 ng/mL in Study 2, were tapered over time post-transplant. Median creatinine levels in Study 1 were 133 and 132 micromol/L at 6 months in the 1.5 and 3 mg/day groups, respectively, and 130 micromol/L in both groups in Study 2. Biopsy-proven acute rejection (BPAR) occurred in 25.0% and 15.2% of patients in the 1.5 and 3 mg/day groups in Study 1, and 13.7% and 15.1% in Study 2. Incidence of BPAR was significantly higher in patients with an everolimus trough <3 ng/mL. There were no significant between-group differences in the composite endpoint of BPAR, graft loss or death, nor any significant between-group differences in adverse events in either study. Concentration-controlled everolimus with low-exposure CsA provided effective protection against rejection with good renal function.     

A Randomized,Controlled Study to Assess the Conversion From Calcineurin‐Inhibitors to Everolimus After Liver Transplantation—PROTECT

Posttransplant immunosuppression with calcineurin inhibitors (CNIs) is associated with impaired renal function, while mTor inhibitors such as everolimus may provide a renal‐sparing alternative. In this randomized 1‐year study in patients with liver transplantation (LTx), we sought to assess the effects of everolimus on glomerular filtration rate (GFR) after conversion from CNIs compared to continued CNI treatment. Eligible study patients received basiliximab induction, CNI with/without corticosteroids for 4 weeks post‐LTx, and were then randomized (if GFR > 50 mL/min) to continued CNIs (N = 102) or subsequent conversion to EVR (N = 101). Mean calculated GFR 11 months postrandomization (ITT population) revealed no significant difference between treatments using the Cockcroft‐Gault formula (?2.9 mL/min in favor of EVR, 95%‐CI: [?10.659; 4.814], p = 0.46), whereas use of the MDRD formula showed superiority for EVR (?7.8 mL/min, 95%‐CI: [?14.366; ?1.191], p = 0.021). Rates of mortality (EVR: 4.2% vs. CNI: 4.1%), biopsy‐proven acute rejection (17.7% vs. 15.3%), and efficacy failure (20.8% vs. 20.4%) were similar. Infections, leukocytopenia, hyperlipidemia and treatment discontinuations occurred more frequently in the EVR group. No hepatic artery thrombosis and no excess of wound healing impairment were noted. Conversion from CNI‐based to EVR‐based immunosuppression proved to be a safe alternative post‐LTx that deserves further investigation in terms of nephroprotection.     

Early Withdrawal of Calcineurin Inhibitors and Everolimus Monotherapy in de novo Liver Transplant Recipients Preserves Renal Function

We designed a randomized trial to assess whether the early withdrawal of cyclosporine (CsA) followed by the initiation of everolimus (Evr) monotherapy in de novo liver transplantation (LT) patients would result in superior renal function compared to a CsA‐based immunosuppression protocol. All patients were treated with CsA for the first 10 days and then randomized to receive Evr in combination with CsA up to day 30, then either continued on Evr monotherapy (Evr group) or maintained on CsA with/without mycophenolate mofetil (CsA group) in case of chronic kidney disease (CKD). Seventy‐eight patients were randomized (Evr n = 52; CsA n = 26). The 1‐year freedom from efficacy failure in Evr group was 75% versus 69.2% in CsA group, p = 0.36. There was no statistically significant difference in patient survival between the two groups. Mean modification of diet in renal disease (MDRD) was significantly better in the Evr group at 12 months (87.7 ± 26.1 vs. 59.9 ± 12.6 mL/min; p < 0.001). The incidence of CKD stage ≥3 (estimated glomerular filtration rate <60 mL/min) was higher in the CsA group at 1 year (52.2% vs. 15.4%, p = 0.005). The results indicate that early withdrawal of CsA followed by Evr monotherapy in de novo LT patients is associated with an improvement in renal function, with a similar incidence of rejection and major complications.     

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.     

Conversion From Cyclosporine to Everolimus at 4.5 Months Posttransplant: 3‐Year Results From the Randomized ZEUS Study

The long‐term effect of conversion from calcineurin inhibitor (CNI) therapy to an mTOR inhibitor requires clarification. Following completion of the 12‐month, open‐label, multicenter ZEUS study, in which 300 kidney transplant recipients were randomized to continue cyclosporine (CsA) or convert to everolimus at 4.5 months posttransplant, outcomes were assessed at month 36 (n = 284; 94.7%). CNI therapy was reintroduced in 28.4% of everolimus patients by month 36. The primary efficacy endpoint, estimated glomerular filtration rate (Nankivell, ANCOVA) was significantly higher with everolimus versus the CsA group at month 24 (7.6 mL/min/1.73 m², 95%CI 4.3, 11.0 mL/min/1.73 m²; p < 0.001) and month 36 (7.5 mL/min/1.73 m², 95%CI 3.6, 11.4 mL/min/1.73 m²; p < 0.001). The incidence of biopsy‐proven acute rejection from randomization to month 36 was 13.0% in the everolimus arm and 4.8% in the CsA arm (p = 0.015). Patient and graft survival, as well as incidences of malignancy, severe infections and hospitalization, were similar between groups. Kidney transplant patients who are converted from CsA to everolimus at month 4.5 and who remain on everolimus thereafter may achieve a significant improvement in renal function that is maintained to 3 years. There was a significantly higher rate of rejection in the everolimus arm but this did not exert a deleterious effect by 3 years posttransplant.     

Early Adequate Mycophenolic Acid Exposure is Associated with Less Rejection in Kidney Transplantation

This study examines the importance of early mycophenolic acid (MPA) exposure in the cyclosporine- and mycophenolate mofetil (MMF)-treated kidney transplant population. We prospectively evaluated 94 first solitary kidney transplant patients treated with cyclosporine (Neoral), MMF, and prednisone. Basiliximab was also given to 72 recipients. MPA exposure was measured by HPLC using a limited sampling estimate of 12 h area under the curve (AUC [0-12]) within the first week. Efficacy was determined by the occurrence of acute rejection and toxicity by the need to reduce MMF doses within the first 3 months post-transplantation. Acute rejection was observed in 14 (15%) and MMF toxicity in 27 (29%). Receiver operator curve analysis shows that MPA AUC [0-12] on day 3 was predictive of efficacy (c = 0.72, p = 0.007) but not toxicity (c = 0.57, p = 0.285). A separate analysis of only patients on basiliximab shows that the MPA AUC [0-12] on day 3 was also predictive of efficacy (c = 0.80, p = 0.01). Therefore early adequate exposure to MPA by day 3 is associated with low acute rejection but cannot predict toxicity. Adequate MPA exposure is also important with basiliximab induction therapy.     

A Phase III Study of Belatacept‐based Immunosuppression Regimens versus Cyclosporine in Renal Transplant Recipients (BENEFIT Study)

Belatacept, a costimulation blocker, may preserve renal function and improve long‐term outcomes versus calcineurin inhibitors in kidney transplantation. This Phase III study (Belatacept Evaluation of Nephroprotection and Efficacy as First‐line Immunosuppression Trial) assessed a more intensive (MI) or less intensive (LI) regimen of belatacept versus cyclosporine in adults receiving a kidney transplant from living or standard criteria deceased donors. The coprimary endpoints at 12 months were patient/graft survival, a composite renal impairment endpoint (percent with a measured glomerular filtration rate (mGFR) <60 mL/min/1.73 m² at Month 12 or a decrease in mGFR ≥10 mL/min/1.73 m² Month 3–Month 12) and the incidence of acute rejection. At Month 12, both belatacept regimens had similar patient/graft survival versus cyclosporine (MI: 95%, LI: 97% and cyclosporine: 93%), and were associated with superior renal function as measured by the composite renal impairment endpoint (MI: 55%; LI: 54% and cyclosporine: 78%; p ≤ 0.001 MI or LI versus cyclosporine) and by the mGFR (65, 63 and 50 mL/min for MI, LI and cyclosporine; p ≤ 0.001 MI or LI versus cyclosporine). Belatacept patients experienced a higher incidence (MI: 22%, LI: 17% and cyclosporine: 7%) and grade of acute rejection episodes. Safety was generally similar between groups, but posttransplant lymphoproliferative disorder was more common in the belatacept groups. Belatacept was associated with superior renal function and similar patient/graft survival versus cyclosporine at 1 year posttransplant, despite a higher rate of early acute rejection.     

Sotrastaurin in Calcineurin Inhibitor–Free Regimen Using Everolimus in De Novo Kidney Transplant Recipients

Sotrastaurin, a novel selective protein‐kinase‐C inhibitor, inhibits early T cell activation via a calcineurin‐independent pathway. Efficacy and safety of sotrastaurin in a calcineurin inhibitor—free regimen were evaluated in this two‐stage Phase II study of de novo kidney transplant recipients. Stage 1 randomized 131 patients (2:1) to sotrastaurin 300 mg or cyclosporine A (CsA). Stage 2 randomized 180 patients (1:1:1) to sotrastaurin 300 or 200 mg or CsA. All patients received basiliximab, everolimus (EVR) and prednisone. Primary endpoint was composite efficacy failure rate of treated biopsy‐proven acute rejection, graft loss, death or lost to follow‐up. Main safety assessment was estimated glomerular filtration rate (eGFR) by MDRD‐4 at Month 12. Composite efficacy failure rates at 12 months were higher in sotrastaurin arms (Stage 1: 16.5% and 10.9% for sotrastaurin 300 mg and CsA; Stage 2: 27.2%, 34.5% and 19.4% for sotrastaurin 200 mg, 300 mg and CsA). eGFR was significantly better in sotrastaurin groups versus CsA at most time points, except at 12 months. Gastrointestinal and cardiac adverse events were more frequent with sotrastaurin. Higher treatment discontinuation, deaths and graft losses occurred with sotrastaurin 300 mg. Sotrastaurin combined with EVR showed higher efficacy failure rates and some improvement in renal allograft function compared to a CsA‐based therapy.     

Long‐Term Exposure to Belatacept in Recipients of Extended Criteria Donor Kidneys

Patients in the BENEFIT‐EXT study received extended criteria donor kidneys and a more intensive (MI) or less intensive (LI) belatacept immunosuppression regimen, or cyclosporine A (CsA). Patients who remained on assigned therapy through year 3 were eligible to enter a long‐term extension (LTE) study. Three hundred four patients entered the LTE (n = 104 MI; n = 113 LI; n = 87 CsA), and 260 continued treatment through year 5 (n = 91 MI; n = 100 LI; n = 69 CsA). Twenty patients died during the LTE (n = 5 MI; n = 9 LI; n = 6 CsA), and eight experienced graft loss (n = 2 MI; n = 1 LI; n = 5 CsA). Three patients experienced an acute rejection episode (n = 2 MI; n = 1 LI). The incidence rate of serious adverse events, viral infections and fungal infections was similar across groups during the LTE. There were four cases of posttransplant lymphoproliferative disorder (PTLD) from the beginning of the LTE to year 5 (n = 3 LI; n = 1 CsA); two of three PTLD cases in the LI group were in patients who were seronegative for Epstein–Barr virus (EBV(?)) at transplantation. Mean ± SD calculated GFR at year 5 was 55.9 ± 17.5 (MI), 59.0 ± 29.1 (LI) and 44.6 ± 16.4 (CsA) mL/min/1.73 m². Continued treatment with belatacept was associated with a consistent safety profile and sustained improvement in renal function versus CsA over time.

     

Therapeutic drug monitoring for everolimus in kidney transplantation using 12-month exposure, efficacy, and safety data

The aims of the current study were to determine whether therapeutic drug monitoring (TDM) might benefit kidney transplant recipients receiving everolimus, and to establish dosage recommendations when everolimus is used in combination with cyclosporine and corticosteroids. The analysis was based on data from 779 patients enrolled in two 12-month trials. Everolimus trough concentrations >/=3 ng/mL were associated with a reduced incidence in biopsy-proven acute rejection (BPAR) in the first month (p = 0.0001) and the first 6 months (p = 0.0001), and reduced graft loss compared with lower concentrations (4% vs. 20%, respectively). By contrast, cyclosporine in the standard concentration range had no impact on BPAR within the same timeframes. Most patients receiving everolimus 1.5 or 3 mg/d achieved trough concentrations above the therapeutic threshold of 3 ng/mL, regardless of reductions in cyclosporine dose. TDM simulation showed that just two dose adjustments would achieve median everolimus trough values >/=3 ng/mL in 95% of patients during the first 6 months. This investigation indicates that improved efficacy is likely when TDM is considered as an integral component of the immunosuppressive strategy of everolimus.     

Immunosuppression with Belatacept‐Based,Corticosteroid‐Avoiding Regimens in De Novo Kidney Transplant Recipients

Current immunosuppressive regimens in renal transplantation typically include calcineurin inhibitors (CNIs) and corticosteroids, both of which have toxicities that can impair recipient and allograft health. This 1‐year, randomized, controlled, open‐label, exploratory study assessed two belatacept‐based regimens compared to a tacrolimus (TAC)‐based, steroid‐avoiding regimen. Recipients of living and deceased donor renal allografts were randomized 1:1:1 to receive belatacept‐mycophenolate mofetil (MMF), belatacept‐sirolimus (SRL), or TAC‐MMF. All patients received induction with 4 doses of Thymoglobulin (6 mg/kg maximum) and an associated short course of corticosteroids. Eighty‐nine patients were randomized and transplanted. Acute rejection occurred in 4, 1 and 1 patient in the belatacept‐MMF, belatacept‐SRL and TAC‐MMF groups, respectively, by Month 6; most acute rejection occurred in the first 3 months. More than two‐thirds of patients in the belatacept groups remained on CNI‐ and steroid‐free regimens at 12 months and the calculated glomerular filtration rate was 8–10 mL/min higher with either belatacept regimen than with TAC‐MMF. Overall safety was comparable between groups. In conclusion, primary immunosuppression with belatacept may enable the simultaneous avoidance of both CNIs and corticosteroids in recipients of living and deceased standard criteria donor kidneys, with acceptable rates of acute rejection and improved renal function relative to a TAC‐based regimen.     

Proton Pump Inhibitors Reduce Mycophenolate Exposure in Heart Transplant Recipients—A Prospective Case-Controlled Study

This prospective study investigates the impact of proton pump inhibitors (PPI) on mycophenolic acid (MPA) pharmacokinetics in heart transplant recipients receiving mycophenolate mofetil (MMF) and tacrolimus. MPA plasma concentrations at baseline (C_{0  h}), 30 min (C_{0.5  h}), 1(C_{1  h}) and 2 h (C_{2  h}) were obtained by high-performance liquid chromatography (HPLC) in 22 patients treated with pantoprazole 40 mg and MMF 2000 mg. Measurements were repeated 1 month after pantoprazole withdrawal. A four-point limited-sampling strategy was applied to calculate the MPA area under the curve (MPA-AUC). Predose MPA concentrations with PPI were 2.6 ± 1.6 mg/L versus 3.4 ± 2.7 mg/L without PPI (p = ns). Postdose MPA concentrations were lower with PPI at C_{0.5  h} (8.3 ± 5.7 mg/L vs. 18.3 ± 11.3 mg/L, p = 0.001) and C_{1  h} (10.0 ± 5.6 mg/L vs. 15.8 ± 8.4 mg/L, p = 0.004), without significant differences at C_{2  h} (8.3 ± 6.5 mg/L vs. 7.6 ± 3.9 mg/L). The MPA-AUC was significantly lower with PPI medication (51.2 ± 26.6 mg × h/L vs. 68.7 ± 30.3 mg × h/L; p = 0.003). The maximum concentration of MPA (MPA-C_max) was lower (12.2 ± 7.5 mg/L vs. 20.6 ± 9.3 mg/L; p = 0.001) and the time to reach MPA-C_max (t_max) was longer with PPI (60.0 ± 27.8 min vs. 46.4 ± 22.2 min; p = 0.05). This is the first study to document an important drug interaction between a widely used immunosuppressive agent and a class of drugs frequently used in transplant patients. This interaction results in a decreased MMF drug exposure which may lead to patients having a higher risk for acute rejection and transplant vasculopathy.     

Cyclosporine Sparing with Mycophenolate Mofetil, Daclizumab and Corticosteroids in Renal Allograft Recipients: The CAESAR Study

Although the calcineurin inhibitors (CNI) cyclosporine (CsA) and tacrolimus are highly effective immunosuppressants, they are associated with serious side effects. There is great interest in immunosuppressive regimens that permit reduction or elimination of CNIs, while maintaining adequate immunosuppression and acceptable acute rejection rates. Patients (n = 536) receiving their first renal allograft were randomized to one of three immunosuppressant regimens: daclizumab, mycophenolate mofetil (MMF), corticosteroids (CS) and low-dose CsA (target trough levels of 50-100 ng/mL), weaned from month 4 and withdrawn by month 6; daclizumab, MMF, CS and low-dose CsA; or MMF, CS and standard-dose CsA. Mean GFR 12 months after transplantation (primary end point) was not statistically different in the CsA withdrawal and low-dose CsA groups (both 50.9 mL/min/1.73 m(2)) vs. the standard-dose CsA group (48.6 mL/min/1.73 m(2)). At 12 months, the incidence of biopsy-proven acute rejection was significantly higher in the CsA withdrawal group (38%) vs. the low- or standard-dose CsA groups (25.4% and 27.5%, respectively; p < 0.05). In summary, a regimen of continuous low-dose CsA with MMF, CS and daclizumab induction is a clinically safe and effective immunosuppressive regimen in renal transplant recipients.     

Sotrastaurin,a Novel Small Molecule Inhibiting Protein‐Kinase C: Randomized Phase II Study in Renal Transplant Recipients

Sotrastaurin, a selective protein‐kinase‐C inhibitor, blocks early T‐cell activation through a calcineurin‐independent mechanism. In this study, de novo renal transplant recipients with immediate graft function were randomized 1:2 to tacrolimus (control, n = 44) or sotrastaurin (300 mg b.i.d.; n = 81). All patients received basiliximab, mycophenolic acid (MPA) and steroids. The primary endpoint was the composite of treated biopsy‐proven acute rejection (BPAR), graft loss, death or lost to follow‐up at month 3. The main safety assessment was estimated glomerular filtration rate (eGFR); modification of diet in renal disease (MDRD) at month 3. Composite efficacy failure at month 3 was higher for the sotrastaurin versus control regimen (25.7% vs. 4.5%, p = 0.001), driven by higher BPAR rates (23.6% vs. 4.5%, p = 0.003), which led to early study termination. Median (± standard deviation [SD]) eGFR was higher for sotrastaurin versus control at all timepoints from day 7 (month 3: 59.0 ± 22.3 vs. 49.5 ± 17.7 mL/min/1.73 m², p = 0.006). The most common adverse events were gastrointestinal disorders (control: 63.6%; sotrastaurin: 88.9%) which led to study‐medication discontinuation in two sotrastaurin patients. This study demonstrated a lower degree of efficacy but better renal function with the calcineurin‐inhibitor‐free regimen of sotrastaurin+MPA versus the tacrolimus‐based control. Ongoing studies are evaluating alternative sotrastaurin regimens .     

Efficacy and safety of conversion from cyclosporine to everolimus in living‐donor kidney transplant recipients: an analysis from the ZEUS study

Conversion of living‐donor kidney transplant patients from calcineurin inhibitor therapy to an mTOR inhibitor is poorly documented. In the prospective, multicentre ZEUS study, 300 kidney transplant recipients without prior rejection (Banff grade >1) and serum creatinine ≤265 μmol/l were randomized to continue cyclosporine or convert to everolimus at 4.5 months post‐transplant. In a post hoc analysis of 80 living‐donor recipients, adjusted estimated GFR (Nankivell) at month 12 (the primary endpoint) was 74.3 (95% CI [70.7, 77.9]) ml/min/1.73 m² with everolimus versus 63.8 (95% CI [60.0, 67.7]) ml/min/1.73 m²) with cyclosporine, a difference of 10.5 ml/min/1.73 m² in favour of everolimus (P < 0.001). From randomization to month 12, adjusted estimated GFR increased by a mean of 9.8 (95% CI [6.2, 13.4]) ml/min/1.73 m² with everolimus versus ?0.7 (95% CI [?4.6, 3.1]) ml/min/1.73 m²) (P < 0.001) with cyclosporine. There were six biopsy‐proven acute rejection episodes in everolimus‐treated patients (five Banff grade I) and one episode in cyclosporine‐treated patients (Banff grade 1). Overall safety profile was similar between groups. Discontinuation due to adverse events occurred in three everolimus patients (7.1%) and five cyclosporine patients (13.2%) between randomization and month 12. Initiation of everolimus with early elimination of calcineurin therapy is associated with a significant renal benefit at 12 months post‐transplant that is observed in both living and deceased‐donor recipients. (clinicaltrials.gov NCT00154310)     

Donor‐Specific HLA Antibodies in a Cohort Comparing Everolimus With Cyclosporine After Kidney Transplantation

Donor‐specific HLA antibodies (DSA) have a negative impact on kidney graft survival. Therefore, we analyzed the occurrence of DSA and antibody‐mediated rejection (AMR) in patients from two prospective randomized trials in our center. At 3–4.5 months posttransplant 127 patients were randomized to continue cyclosporine or converted to everolimus therapy. The presence of DSA was prospectively assessed using Luminex assays. AMR was defined according to the Banff 2009 classification. Antibody screening was available in 126 patients with a median follow‐up of 1059 days. Seven out of 65 (10.8%) patients on cyclosporine developed DSA after a median of 991 days. In comparison, 14/61 patients (23.0%) randomized to everolimus developed DSA after 551 days (log‐rank: p = 0.048). Eight patients on everolimus compared to two patients on cyclosporine developed AMR (log‐rank: p = 0.036). Four of 10 patients with AMR—all in the everolimus group—lost their graft. A multivariate regression model revealed everolimus, >3 mismatches and living donor as significant risk factors for DSA. Acute rejection within the first year, >3 mismatches, everolimus and living donor were independent risk factors for AMR. This single center analysis demonstrates for the first time that everolimus‐based immunosuppression is associated with an increased risk for the development of DSA and AMR.