Mycophenolate Mofetil and Sirolimus Combination in Renal Transplantation

Mycophenolate mofetil (MMF) and sirolimus (SRL) are potent non-nephrotoxic xenobiotic immunosuppressants. Their complementary properties may provide the rationale for their combination in induction and maintenance regimens. MMF, a reversible inhibitor of inosin monophosphate dehydrogenase (IMPDH) acts as an antiproliferative drug; and SRL, an mTOR (mammalian target of rapamycin) inhibitor, inhibits cell proliferation driven by growth factors. Early experiences with the use of the SRL, MMF and steroid combination yielded insufficient prophylaxis of acute rejection. However, the introduction of induction therapy with mono- or polyclonal antilymphocyte antibodies to the SRL-MMF and steroid combination brings an efficient acute rejection prophylaxis, while improving renal function and/or reducing of chronic allograft nephropathy (CAN). However, adverse events related to the use of this drug combination (mainly haematological and surgery-related) result in a high rate of discontinuations in some trials, which may hamper the potential benefits of this calcineurin-inhibitor (CNI)-free strategy. Also, currently under investigation is whether in long-term immunosuppression, in MMF-treated patients, CNIs can be replaced by SRL to avoid and/or halt progression of chronic nephropathy and to improve graft survival. However, some authors reported a high proportion of patients with oral ulcers and proteinuria after switching to SRL. In short, refining the use of MMF and SRL may provide a better risk/benefit ratio to pave the way towards non-nephrotoxic immunosuppression.     

Transient Improvement of Hypertension-Induced Chronic Renal Failure with Mycophenolate Mofetil Treatment

A young female with essential hypertension developed progressive azotemia; renal biopsy showed hypertensive nephrosclerosis with considerable tubulointerstitial disease and cellular infiltration. The addition of mycophenolate mofetil (MMF) to her antihypertensive treatment resulted in a dramatic improvement of renal function during the following three months. When the patient discontinued MMF treatment, end-stage renal failure rapidly developed. This patient represents the first report of the beneficial use of MMF in non-immune chronic renal disease and demonstrates that significant functional improvement may be obtained with the addition of MMF to the treatment of hypertensive nephrosclerosis for patients in whom there is significant tubulointerstitial inflammatory infiltration.     

Mycophenolate revisited

The patent of mycophenolate mofetil (MMF) has expired, and for enteric‐coated mycophenolate sodium (EC‐MPS), this will happen in 2017. In the twenty years these drugs have been used, they have become extremely popular. In this review, the reasons for the popularity of mycophenolate are discussed, including the benefits compared to azathioprine. MMF and EC‐MPS are therapeutically equivalent. Although neither is considered to be a narrow therapeutic index drug, this should not lead to careless switching between the innovator drug and generic formulations, or between one generic formulation and another. The pipeline of new immunosuppressive drugs is dry, and it is very likely that we will be using mycophenolate for many more years to come as a first‐line immunosuppressive drug in our transplant population. Whether or not the development of donor‐specific anti‐HLA antibodies is related to drug exposure (mycophenolic acid concentrations) remains to be investigated.     

Sirolimus with Neoral Versus Mycophenolate Mofetil with Neoral is Associated with Decreased Renal Allograft Survival

To evaluate the association between a regimen of cyclosporine microemulsion (CsA) + sirolimus (Rapa) treatment versus CsA and mycophenolate mofetil (MMF) and renal allograft survival, we analyzed 23 016 primary recipients reported to the Scientific Registry of Transplant Recipients between January 1, 1998 and July 26, 2003. Univariate Kaplan-Meier analysis and multivariate Cox proportional hazard models correcting for demographic and clinical covariates were used to estimate the relative risks for CsA+Rapa versus CsA+MMF-treated patients reaching study endpoints. Subgroup analyses were conducted for recipient ethnicity and donor type. CsA+Rapa was associated with significantly lower graft survival (74.6% vs. 79.3% at 4 years, p = 0.002) and death-censored graft survival (83.7% vs. 87.2%, p = 0.003) compared to CsA+MMF. In multivariate analyses, CsA+Rapa was associated with a significantly increased risk for graft loss, death-censored graft loss and decline in renal function (HR = 1.22, p = 0.002; HR = 1.22, p = 0.018 and HR = 1.25, p < 0.001, respectively). Similar results were obtained in recipient ethnicity and donor type subgroups. In summary, CsA+Rapa was associated with significantly worse graft survival and death-censored graft survival compared to CsA+MMF, and likely reflects full-dose CsA +Rapa. Outcomes regarding alternative strategies of Rapa utilization with reduced CsA, with alternative agents or with no calcineurin inhibitor cannot be extrapolated from these data.     

Effect of Corticosteroid Withdrawal on Tacrolimus and Mycophenolate Mofetil Exposure in a Randomized Multicenter Study

As corticosteroid‐sparing protocols are increasingly utilized in kidney transplant recipients, it is crucial to understand potential drug interactions between tacrolimus (TAC) and the effect of corticosteroid withdrawal as well as to characterize dose adjustments of mycophenolate mofetil (MMF) in this setting. This prospective, multicenter, randomized, double‐blind study included 397 patients who were randomized on posttransplant day 8 to receive either placebo (CSWD) or corticosteroid continuance (CCS). TAC trough levels at week two posttransplant were significantly greater in the CSWD group whereas TAC doses were comparable to the CCS group. This interaction was not observed in the African American subgroup. Higher serum creatinine and potassium levels were also observed in the CSWD group. MMF dose was significantly reduced in the CSWD group by the investigators because of decreased WBC counts, mostly outside of study protocol criteria, despite similar incidence of neutropenia and reported cytomegalovirus infection. Understanding TAC and MMF exposure in the context of corticosteroid‐sparing protocols should allow for improved dosing of immunosuppressants and better management of posttransplant patients.     

Azathioprine in Liver Transplantation: A Reevaluation of Its Use and a Comparison with Mycophenolate Mofetil

Calcineurin inhibitors (CNIs) combined with steroids with or without azathioprine (AZA), have been a standard immunosuppression regimen after liver transplantation (LT). Since 2000 many centers have substituted AZA by mycophenolate mofetil (MMF). However, in LT the superiority of MMF over AZA is not clearly demonstrated. Therefore, we questioned the benefit of MMF versus AZA in LT with regard to rejection, renal dysfunction and hepatitis C virus (HCV) recurrence and survival. Using a literature search, relevant randomized controlled trials (RCT) and cohort studies were identified: two RCTs compared MMF to AZA only for acute rejection. Treated rejection was less with MMF in only one RCT (38.5% vs. 47.7%; p = 0.025), with no difference in patient and graft survival. No RCTs compared MMF and AZA in patients with CNI-related chronic renal dysfunction. Among two studies evaluating MMF, with substitution of AZA, one was stopped due to severe rejection. Recurrent HCV was less severe in 5/9 studies with AZA compared with 2/17 using MMF, six of which documented worse recurrence. Published data in LT show little, if any, clinical benefit of MMF versus AZA. RCTs should reevaluate AZA in LT. Evaluation of HCV replication and recurrence will be particularly important as AZA may have advantages over MMF.     

Mycophenolate Mofetil Is Associated with Altered Expression of Chronic Renal Transplant Histology

Mycophenolate mofetil (MMF) reduces acute rejection in controlled trials of kidney transplantation and is associated with better registry graft survival. Recent experimental studies have demonstrated additional antifibrotic properties of MMF, however, human histological data are lacking. We evaluated sequential prospective protocol kidney biopsies from two historical cohorts treated with cyclosporine (CSA)-based triple therapy including prednisolone and either MMF (n = 25) or azathioprine (AZA, n = 25). Biopsies (n = 360) were taken from euglycemic kidney-pancreas transplant recipients. Histology was independently assessed by the Banff schema and electron microscopic morphometry. MMF reduced acute rejection and OKT3 use (p < 0.05) compared with AZA. MMF therapy was associated with limited chronic interstitial fibrosis, striped fibrosis and periglomerular fibrosis (p < 0.05-0.001), mesangial matrix accumulation (p < 0.01), chronic glomerulopathy scores (p < 0.05) and glomerulosclerosis (p < 0.05). MMF was associated with delayed expression of CSA nephrotoxicity, reduced arteriolar hyalinosis, striped fibrosis and tubular microcalcification (p < 0.05-0.001). The beneficial effects of MMF remained in recipients without acute rejection. Retrospective analysis shows that MMF therapy was associated with substantially reduced fibrosis in the glomerular, microvascular and interstitial compartments, and a delayed expression of CSA nephrotoxicity. These outcomes may be due to a limitation of immune-mediated injury and suggest a direct effect of reduced fibrogenesis.     

Mycophenolate Mofetil Monotherapy for Severe Side Effects of Calcineurin Inhibitors Following Liver Transplantation

Withdrawal of calcineurin inhibitors (CNI) followed by mycophenolate mofetil (MMF) monotherapy after liver transplantation (LT) remains controversial due to the increased risk of acute rejection and graft loss. The aim of the present study, performed in a large cohort of liver-transplanted patients with severe CNI-induced side effects, was to assess renal function recovery, and safety in terms of liver function, of complete CNI withdrawal and replacement by MMF monotherapy. Fifty-two patients treated with MMF monotherapy for CNI-induced toxicity were analyzed. Mean estimated glomerular filtration rate (eGFR) increased significantly during the period of MMF monotherapy, from 37 ± 10 to 44.7 ± 15 mL/min/1.73 m² at 6 months (p = 0.001) corresponding to a benefit of +17.4% in renal function. eGFR stabilized or improved in 86.5%, 81% and 79% of cases, and chronic renal dysfunction worsened in 13.5%, 19% and 21% of cases, at 6, 12 and 24 months after CNI withdrawal, respectively. Only two patients experienced acute rejection. MMF monotherapy may be efficient at reversing/stabilizing CRD, and appears relatively safe in terms of liver graft function in long-term liver-transplanted patients. However, clinicians must bear in mind the potential risk of rejection and graft loss, and should be very cautious in the management of such 'difficult-to-treat patients'.     

Fixed- or Controlled-Dose Mycophenolate Mofetil with Standard- or Reduced-Dose Calcineurin Inhibitors: The Opticept Trial

Mycophenolate mofetil (MMF) was developed with cyclosporine as a fixed-dose immunosuppressant. More recent data indicate a relationship between mycophenolic acid (MPA) exposure in individuals and clinical endpoints of rejection and toxicity. This 2-year, open-label, randomized, multicenter trial compared the efficacy and safety of concentration-controlled MMF (MMF_CC) dosing with a fixed-dose regimen in 720 kidney recipients. Patients received either (A) MMF_CC and reduced-level calcineurin inhibitor (MMF_CC/CNI_RL); (B) MMF_CC and standard-level CNI (MMF_CC/CNI_SL); or (C) fixed-dose MMF and CNI_SL (MMF_FD/CNI_SL). Antibody induction and steroid use were according to center practice. The primary endpoint was noninferiority (α= 0.05) of group A versus group C for treatment failure (including biopsy-proven acute rejection [BPAR], graft loss and death) at 1 year. Although mean CNI trough levels in group A did not reach the prespecified targets, they were statistically lower than those in groups B and C (p ≤ 0.01 for each comparison). BPAR rates (8.5%) were low across groups. Group A had 19% fewer treatment failures (23% vs. 28%, p = 0.18). MMF doses were highest (p < 0.05), with withdrawals for adverse events the fewest (p = 0.02), in group A. Of the 80% of subjects taking tacrolimus (Tac), those with higher MPA exposure had significantly less rejection (p < 0.001) and diarrhea correlated with Tac, but not with MPA levels. Thus, MMF_CC with low-dose CNI resulted in outcomes not inferior to those with standard CNI exposure and MMF_FD, indicating potential utility of MMF_CC in CNI-sparing regimens.     

Everolimus Versus Mycophenolate Mofetil in Heart Transplantation: A Randomized,Multicenter Trial

In an open‐label, 24‐month trial, 721 de novo heart transplant recipients were randomized to everolimus 1.5 mg or 3.0 mg with reduced‐dose cyclosporine, or mycophenolate mofetil (MMF) 3 g/day with standard‐dose cyclosporine (plus corticosteroids ± induction). Primary efficacy endpoint was the 12‐month composite incidence of biopsy‐proven acute rejection, acute rejection associated with hemodynamic compromise, graft loss/retransplant, death or loss to follow‐up. Everolimus 1.5 mg was noninferior to MMF for this endpoint at month 12 (35.1% vs. 33.6%; difference 1.5% [97.5% CI: –7.5%, 10.6%]) and month 24. Mortality to month 3 was higher with everolimus 1.5 mg versus MMF in patients receiving rabbit antithymocyte globulin (rATG) induction, mainly due to infection, but 24‐month mortality was similar (everolimus 1.5 mg 10.6% [30/282], MMF 9.2% [25/271]). Everolimus 3.0 mg was terminated prematurely due to higher mortality. The mean (SD) 12‐month increase in maximal intimal thickness was 0.03 (0.05) mm with everolimus 1.5 mg versus 0.07 (0.11) mm with MMF (p < 0.001). Everolimus 1.5 mg was inferior to MMF for renal function but comparable in patients achieving predefined reduced cyclosporine trough concentrations. Nonfatal serious adverse events were more frequent with everolimus 1.5 mg versus MMF. Everolimus 1.5 mg with reduced‐dose cyclosporine offers similar efficacy to MMF with standard‐dose cyclosporine and reduces intimal proliferation at 12 months in de novo heart transplant recipients.     

Enteric-Coated Mycophenolate Sodium is Therapeutically Equivalent to Mycophenolate Mofetil in de novo Renal Transplant Patients

The introduction of mycophenolate mofetil (MMF) represented a major advance in transplant medicine, although optimal use may be limited by gastrointestinal (GI) side-effects. An enteric-coated formulation of mycophenolate sodium (EC-MPS; myfortic) has been developed with the aim of improving the upper GI tolerability of mycophenolic acid. Therapeutic equivalence of EC-MPS (720 mg b.i.d.) and MMF (1000 mg MMF b.i.d.), with concomitant cyclosporine microemulsion (Neoral) and corticosteroids, was assessed in 423 de novo kidney transplant patients recruited to a 12-month, double-blind study. Efficacy failure (biopsy-proven acute rejection [BPAR], graft loss, death or loss to follow up) at 6 months (EC-MPS 25.8% vs. MMF 26.2%; 95% CI: [-8.7, +8.0]) demonstrated therapeutic equivalence. At 12 months, the incidence of BPAR, graft loss or death was 26.3% and 28.1%, and of BPAR alone was 22.5% and 24.3% for EC-MPS and MMF, respectively. Among those with BPAR, the incidence of severe acute rejection was 2.1% with EC-MPS and 9.8% with MMF (p=ns). The safety profile and incidence of GI adverse events were similar for both groups. Within 12 months, 15.0% of EC-MPS patients and 19.5% of MMF patients required dose changes for GI adverse events (p=ns). Enteric-coated-MPS 720 mg b.i.d. is therapeutically equivalent to MMF 1000 mg b.i.d. with a comparable safety profile.     

Prospective Registry-Based Observational Cohort Study of the Long-Term Risk of Malignancies in Renal Transplant Patients Treated with Mycophenolate Mofetil

This large prospectively conducted observational cohort study examined the risk of lymphoma and other malignancies with mycophenolate mofetil (MMF) in de novo renal transplant recipients. A total of 6751 patients receiving MMF, and an equal number of matched controls receiving non-MMF-based immunosuppression, were identified from two large registries (Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) and Collaborative Transplant Study (CTS)) and followed for 3 years. The primary endpoint was development of lymphoma. Secondary endpoints included development of any malignancy. There was no evidence of any increased risk of developing lymphoma or malignancy with MMF. The risk of developing lymphoma with MMF compared with the non-MMF cohort was not higher in either the CTS registry (relative risk (95% confidence interval); 0.4 (0.17-0.94)) or the OPTN/UNOS registry (1.04 (0.61-1.78)). In the MMF group, there was a trend toward a lower risk of malignancy in both registries (OPTN/UNOS 0.86 (0.69-1.07); CTS 0.79 (0.61-1.02)) and a significant increase in time to malignancy in the CTS dataset (p < 0.026). This study has demonstrated that MMF is not associated with an increased risk of lymphoma or other malignancies post-renal transplant, and may even be associated with a lower risk in some populations.     

Mycophenolate Blood Level Monitoring: Recent Progress

The concentration–effect relationship for mycophenolic acid (MPA), and the high variability in MPA concentrations in patients on standard dose mycophenolate mofetil (MMF) therapy, for some centers has provided enough evidence to implement therapeutic drug monitoring (TDM) for MMF in daily practice. Two randomized trials Adaption de Posologie du MMF en Greffe Renale (APOMYGRE) and fixed-dose versus concentration controlled (FDCC) investigated the added benefit of TDM for MMF in renal transplant recipients. The APOMYGRE study showed a significant reduction in the incidence of acute rejection in concentration-controlled patients, while the FDCC study had a negative outcome, despite a similar study design. Although it was expected that these prospective trials would give the final answer to the question of whether or not TDM for MMF would be of benefit, it seems that the studies have not had much impact on patient management. Several trials have shown the importance of early adequate exposure to MPA in the first week after transplantation. As it will be hard to improve MPA exposure with TDM, this early, ongoing study now investigates the use of an increased starting dose. The increased starting dose will avoid underexposure to MPA in higher proportions of patients shortly after transplantation but may result in more toxicity in patients with MPA exposures exceeding the upper threshold of the therapeutic window.     

Pharmacokinetic Studies of Mycophenolate Mofetil in Rat Kidney Allograft Recipients

Background A pharmacokinetic estimation of the immunosuppressive activity of mycophenolate mofetil (MPM) was performed in rats with transplanted kidney allografts.
Methods Kidney allografts from Brown Norway rats were transplanted into Lewis rats using a microsurgical technique. MPM, at doses of 5, 10, 15 and 25mg/kg/day, was administered orally every day after transplantation. Pharmacokinetic studies were performed on days 7 and 14, and thereafter every 2 weeks.
Results After the administration of MPM, the plasma concentration of mycophenolic acid (MPA) increased rapidly, peaking at 15 to 30 minutes, and then decreased biexponentially. The peak concentration of MPA and the area under the plasma MPA concentration versus time curves (AUC) significantly correlated with the dosage. MPM administration at 5 and 10mg/kg/day significantly prolonged the graft survival time from 7.1 days to 18.5 days and 85.0 days, respectively. The AUC values on day 7 after transplantation were 32.7,ug-h/mL and 38.6/ig-h/mL in rats receiving 5 and 10mg/kg/day, respectively. However, in rats receiving 1 5mg/kg/day of MPM or more, the AUC value at 7 days was 78.8,ug-h/mL, and almost all of these rats died from gastrointestinal toxicity.
Conclusion MPM monotherapy significantly prolonged rat kidney allograft survival, however, high dosages of MPM caused gastrointestinal toxicity. AUC measurements of the MPA concentration are suitable for the pharmacokinetic monitoring of MPM.     

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.     

Pre-Transplant Inosine Monophosphate Dehydrogenase Activity is Associated with Clinical Outcome After Renal Transplantation

Mycophenolate mofetil (MMF), an inhibitor of inosine monophosphate dehydrogenase (IMPDH) activity, is usually administered as a standard dose of 1 g b.i.d. after renal transplantation. Because MMF dose reductions are associated with inferior outcome, we investigated pre-transplant IMPDH activity, MMF dose reductions and outcome. IMPDH activity was determined in isolated peripheral mononuclear cells immediately prior to renal transplantation. We observed considerable inter-individual variability in pre-transplant IMPDH activity (9.35 +/- 4.22 nmol/mg/h). Thirty of 48 patients (62.5%) with standard MMF dose (1 g b.i.d.) had dose reductions within 3 years post-transplant; these patients also had significantly lower IMPDH activity. The area under the receiver-operating characteristics curve (AUC-ROC) for prediction of dose reduction within 6 months post-transplant was 0.75 (95% CI, 0.61-0.89; p < 0.004). IMPDH activity above the cut-off value, MMF dose reduction and age of recipient were significant contributors for the occurrence of acute rejection in the multivariate logistic regression. Patients with high IMPDH activity and MMF dose reduction had the highest rejection rate (81.8% vs. 36.4%; p < 0.01). Conclusion: Patients with low IMPDH activity experienced more complications of MMF therapy. High pre-transplant IMPDH activity and MMF dose reductions were associated with rejection. Determination of IMPDH activity prior to transplantation may help to improve MMF therapy after renal transplantation.     

Mycophenolate mofetil pharmacokinetics in renal transplant recipients on peritoneal dialysis

We prospectively studied the impact of peritoneal dialysis (PD) on the pharmacokinetics of mycophenolic acid (MPA) in five patients following renal transplantation. Three patients had a glomerular filtration rate (GFR) of less than 10 ml/min and two had a GFR of more than 40 ml/min. Pharmacokinetics of MPA and of its main metabolite, mycophenolic acid glucuronide (MPAG), were studied during two consecutive 12-h periods (with and without PD). After initiation of PD in patients with severe renal impairment (GFR < 10 ml/min), MPA-area-under-the-concentration-curve (AUC) decreased up to 59 % and MPAG-AUC decreased up to 26 %. We did not observe any substantial changes in the MPA-AUC or MPAG-AUC of either patient with a GFR above 40 ml/min. Patients with a reduced GFR had much higher MPAG values than patients with a GFR above 40 ml/l; yet, we did not observe any differences in the MPA values. We found a significant inverse correlation between GFR and MPA-AUC (r = 0.81, P < 0.05) and between GFR and MPAG-AUC (r = 0.94, P < 0.01). While MPA was found only in traces in the peritoneal ultrafiltrate, the cumulative amount of MPAG removed by PD reached up to 2 g/12 h, representing 1.2 g of MPA. This is the first report describing a reduction in MPA-AUC and MPAG-AUC during PD. Further studies are needed to completely understand the pharmacokinetics of mycophenolate mofetil during PD. Received: 20 June 1997 Accepted: 26 August 1997     

The ORION Study: Comparison of Two Sirolimus‐Based Regimens versus Tacrolimus and Mycophenolate Mofetil in Renal Allograft Recipients

Safety and efficacy of two sirolimus (SRL)‐based regimens were compared with tacrolimus (TAC) and mycophenolate mofetil (MMF). Renal transplantation recipients were randomized to Group 1 (SRL+TAC; week 13 TAC elimination [n = 152]), Group 2 (SRL + MMF [n = 152]) or Group 3 (TAC + MMF [n = 139]). Group 2, with higher‐than‐expected biopsy‐confirmed acute rejections (BCARs), was sponsor‐terminated; therefore, Group 2 two‐year data were limited. At 1 and 2 years, respectively, graft (Group 1: 92.8%, 88.5%; Group 2: 90.6%, 89.9%; Group 3: 96.2%, 95.4%) and patient (Group 1: 97.3%, 94.4%; Group 2: 95.2%, 94.5%; Group 3: 97.0%, 97.0%) survival rates were similar. One‐ and 2‐year BCAR incidence was: Group 1, 15.2%, 17.4%; Group 2, 31.3%, 32.8%; Group 3, 8.2%, 12.3% (Group 2 vs. 3, p < 0.001). Mean 1‐ and 2‐year modified intent‐to‐treat glomerular filtration rates (mL/min) were similar. Primary reason for discontinuation was adverse events (Group 1, 34.2%; Group 2, 33.6%; Group 3, 22.3%; p < 0.05). In Groups 1 and 2, delayed wound healing and hyperlipidemia were more frequent. One‐year post hoc analysis of new‐onset diabetes posttransplantation was greater in TAC recipients (Groups 1 and 3 vs. 2, 17% vs. 6%; p = 0.004). Between‐group malignancy rates were similar. The SRL‐based regimens were not associated with improved outcomes for kidney transplantation patients.