Randomized Controlled Trial of Sirolimus Conversion in Cardiac Transplant Recipients With Renal Insufficiency

This randomized, comparative, multinational phase 3b/4 study of patients 1–8 years postcardiac transplantation (mean 3.9 years) evaluated the effect of conversion from a calcineurin inhibitor (CNI) to sirolimus on renal function in patients with renal insufficiency. In total, 116 patients on CNI therapy with GFR 40–90 mL/min/1.73m² were randomized (1:1) to sirolimus (n = 57) or CNI (n = 59). Intent‐to‐treat analysis showed the 1‐year adjusted mean change from baseline in creatinine clearance (Cockcroft‐Gault) was significantly higher with sirolimus versus CNI treatment (+3.0 vs. ?1.4 mL/min/1.73 m², respectively; p = 0.004). By on‐therapy analysis, values were +4.7 and –2.1, respectively (p < 0.001). Acute rejection (AR) rates were numerically higher in the sirolimus group; 1 AR with hemodynamic compromise occurred in each group. A significantly higher treatment discontinuation rate due to adverse events (AEs; 33.3% vs. 0%; p < 0.001) occurred in the sirolimus group. Most common treatment‐emergent AEs significantly higher in the sirolimus group were diarrhea (28.1%), rash (28.1%) and infection (47.4%). Conversion to sirolimus from CNI therapy improved renal function in cardiac transplant recipients with renal impairment, but was associated with an attendant AR risk and higher discontinuation rate attributable to AEs.     

Kidney transplantation with sirolimus and mycophenolate mofetil-based immunosuppression: 5-year results of a randomized prospective trial compared to calcineurin inhibitor drugs

BACKGROUND: We report the 5-year outcomes from a randomized prospective trial in primary adult renal allograft recipients, designed to evaluate calcineurin inhibitor (CNI)-free immunosuppression on kidney transplant function. METHODS: Sixty-one patients were randomized to either sirolimus (n=31) or cyclosporine (n=30) after basiliximab induction and mycophenolate mofetil (MMF) with steroids. Sirolimus was concentration controlled at 10-12 ng/mL for at least 6 months. RESULTS: After 5 years, sirolimus-MMF-steroids compared to cyclosporine-MMF-steroids provides similar patient survival (87.1 vs. 90%, P=0.681), acute rejection rates (12.9 vs. 23.3%, P=0.22), total cholesterol (209.1 vs. 204.3 mg/dL, P=0.973), urine protein/creatinine ratios (0.398 vs. 0.478 mg/dL, P=0.72), and overall medical and surgical morbidity (P=NS). Although unadjusted patient survival was similar, sirolimus based CNI-free patients had longer death censored graft survival (96.4 vs. 76.7%, P=0.0265), higher glomerular filtration rate (GFR) by the abbreviated Modified Diet in Renal Disease (66.7 vs. 50.7 cc/min, P=0.0075), and fewer graft losses from chronic allograft nephropathy. The Banff chronic scores at two years were strong predictors of 5-year GFR. At 5 years, there were six de novo (three solid organ, three skin) cancers in the CNI group and only two de novo (one skin, one leukemia, no solid organ) cancers in the sirolimus group (P=NS). CONCLUSIONS: This study of low to moderate risk patients demonstrates that excellent 5-year kidney transplant outcomes can be achieved without CNI drugs, when therapeutic drug monitoring of sirolimus is employed. The application of CNI drug avoidance protocols to high-risk recipients (retransplants, highly sensitized, etc.), extrarenal allograft recipients, or alternative drug regimens such as steroid or MMF elimination should be subjected to controlled trials.     

Daclizumab Versus Rabbit Antithymocyte Globulin in High‐Risk Renal Transplants: Five‐Year Follow‐up of a Randomized Study

We previously reported a randomized controlled trial in which 227 de novo deceased‐donor kidney transplant recipients were randomized to rabbit antithymocyte (rATG, Thymoglobulin) or daclizumab if they were considered to be at high immunological risk, defined as high panel reactive antibodies (PRA), loss of a first kidney graft through rejection within 2 years of transplantation, or third or fourth transplantation. Patients treated with rATG had lower incidences of biopsy‐proven acute rejection (BPAR) and steroid‐resistant rejection at 1 year. Patients were followed to 5 years posttransplant in an observational study; findings are described here. Treatment with rATG was associated with a lower rate of BPAR at 5 years (14.2% vs. 26.0% with daclizumab; p = 0.035). Only one rATG‐treated patient (0.9%) and one daclizumab‐treated patient (1.0%) developed BPAR after 1 year. Five‐year graft and patient survival rates, and renal function, were similar between the two groups. Overall graft survival at 5 years was significantly higher in patients without BPAR (81.0% vs. 54.8%; p < 0.001). In conclusion, rATG is superior to daclizumab for the prevention of BPAR among high‐immunological‐risk renal transplant recipients. Overall graft survival at 5 years was approximately 70% with either induction therapy, which compares favorably to low‐risk cohorts.     

A Phase III Study of Belatacept Versus Cyclosporine in Kidney Transplants from Extended Criteria Donors (BENEFIT‐EXT Study)

Recipients of extended criteria donor (ECD) kidneys are at increased risk for graft dysfunction/loss, and may benefit from immunosuppression that avoids calcineurin inhibitor (CNI) nephrotoxicity. Belatacept, a selective costimulation blocker, may preserve renal function and improve long‐term outcomes versus CNIs. BENEFIT‐EXT (Belatacept Evaluation of Nephroprotection and Efficacy as First‐line Immunosuppression Trial—EXTended criteria donors) is a 3‐year, Phase III study that assessed a more (MI) or less intensive (LI) regimen of belatacept versus cyclosporine in adult ECD kidney transplant recipients. The coprimary endpoints at 12 months were composite patient/graft survival and a composite renal impairment endpoint. Patient/graft survival with belatacept was similar to cyclosporine (86% MI, 89% LI, 85% cyclosporine) at 12 months. Fewer belatacept patients reached the composite renal impairment endpoint versus cyclosporine (71% MI, 77% LI, 85% cyclosporine; p = 0.002 MI vs. cyclosporine; p = 0.06 LI vs. cyclosporine). The mean measured glomerular filtration rate was 4–7 mL/min higher on belatacept versus cyclosporine (p = 0.008 MI vs. cyclosporine; p = 0.1039 LI vs. cyclosporine), and the overall cardiovascular/metabolic profile was better on belatacept versus cyclosporine. The incidence of acute rejection was similar across groups (18% MI; 18% LI; 14% cyclosporine). Overall rates of infection and malignancy were similar between groups; however, more cases of posttransplant lymphoproliferative disorder (PTLD) occurred in the CNS on belatacept. ECD kidney transplant recipients treated with belatacept‐based immunosuppression achieved similar patient/graft survival, better renal function, had an increased incidence of PTLD, and exhibited improvement in the cardiovascular/metabolic risk profile versus cyclosporine‐treated patients.     

Immunosuppression without calcineurin inhibition: optimization of renal function in expanded criteria donor renal transplantation

Abstract: Introduction: To assess the efficacy of calcineurin inhibitor (CNI)‐free immunosuppression vs. calcineurin‐based immunosuppression in patients receiving expanded criteria donor (ECD) kidneys. Patient and methods: Thirteen recipients of ECD kidneys were enrolled in this pilot study and treated with induction therapy and maintained on sirolimus, mycophenolate mofetil (MMF) and prednisone. A contemporaneous control group was randomly selected comprised of 13 recipients of ECD kidneys who had been maintained on CNI plus MMF and prednisone. Results: For the study group vs. the control group, two‐yr graft survival was 92.3% vs. 84.6% (p = NS), two‐yr patient survival was 100% vs. 92.3% (p = NS) and the acute rejection rates were 23% vs. 31% (p = NS), respectively. Renal function was significantly better in the study group compared with control up to the six‐month mark, after which, it remained numerically but not statistically significant. Complications were more common in the study group, but serious adverse events requiring discontinuation were rare. Conclusion: This pilot study demonstrates that CNI‐free regimens can be safely implemented in patients receiving ECD kidneys with excellent two‐yr patient and graft survival and good renal allograft function. Longer follow‐up in larger randomized controlled trials are necessary to establish these findings.     

Optimizing the clinical utility of sirolimus‐based immunosuppression for kidney transplantation

While calcineurin inhibitors (CNIs) are effective for preventing acute rejection in kidney transplant recipients, long‐term use may cause chronic kidney injury and is associated with increased risks of cardiovascular events, cancer, and infection‐associated death. Immunosuppression strategies are needed to balance risks of acute and subclinical rejection with long‐term benefits of improved kidney function. Sirolimus, an inhibitor of mammalian target of rapamycin, is used for immunosuppression in kidney transplantation. Its clinical utility has evolved, over more than 15 years, including de novo sirolimus with and without concomitant CNIs and conversion from CNI‐based regimens to sirolimus. Sirolimus‐containing regimens are associated with preservation of good renal function, with promising characteristics for improving long‐term graft and patient survival, including antiviral and anticancer effects. Based on clinical evidence, use of low‐dose sirolimus in a de novo approach with tacrolimus/steroids in the immediate posttransplantation period is appropriate. A feasible alternative is a long term, CNI‐free combination with mycophenolate mofetil (following CNI‐to‐sirolimus conversion at 3‐6 months). These strategies are appropriate for a broad range of patients with various levels of immunologic risk, including those receiving expanded criteria donor kidneys or at increased risk of delayed graft function, particular challenges in Latin America and other global regions.     

Comparison of four different immunosuppression protocols without long-term steroid therapy in kidney recipients monitored by surveillance biopsy: five-year outcomes

Induction and maintenance immunosuppression protocols with or without long-term steroid therapy in kidney transplant recipients are variable and are transplant center-specific. The aim of this prospective randomized pilot study was to compare 5-year outcomes in kidney recipients maintained on 4 different calcineurin inhibitor (CNI)-based immunosuppression protocols without long-term steroid therapy. Two hundred consenting patients who received kidney transplants between June 2000 and October 2004 were enrolled in 4 immunosuppression protocol groups, with 50 patients in each group: cyclosporine (CSA)/mycophenolate mofetil (MMF), CSA/sirolimus (SRL), tacrolimus (TAC)/MMF, and TAC/SRL. Induction therapy was done with basiliximab and methylprednisolone. Steroids were withdrawn on post-transplant day 2, and long-term steroid therapy was not used. Demographic characteristics among the four groups were comparable; approximately 50% of the recipients were African American and > or =80% of the kidneys transplanted were from deceased donors. Clinical acute rejection (CAR) was confirmed by biopsy and treated with intravenous pulse steroid therapy. Steroid-unresponsive CAR was treated with Thymoglobulin. Surveillance biopsies were performed at 1, 6, 12, 24, 36, 48, and 60 months to evaluate subclinical acute rejection (SCAR), chronic allograft injury (CAI), and other pathological changes per the Banff 2005 schema. The primary end point was CAR, and secondary end points were 5-year patient and graft survival rates, renal function, SCAR, CAI, and adverse events. In the first year post-transplant, the incidence of CAR was 18% in the CSA/MMF group, 8% in the CSA/SRL group, 14% in the TAC/MMF group, and 4% in the TAC/SRL group (CSA/MMF vs. TAC/SRL; p=0.05). The incidence of SCAR was 22% in the CSA/MMF group, 8% in the CSA/SRL group, 16% in the TAC/MMF group, and 6% in the TAC/SRL group (CSA/MMF vs. CSA/SRL and TAC/SRL; p=0.05). After the first year, the incidences of CAR and SCAR decreased and were comparable in all 4 groups. At 5 years post-transplant, cumulative CAI due to interstitial fibrosis/tubular atrophy (IF/TA), hypertension (HTN), and chronic calcineurin inhibitor (CNI) toxicity was observed in 54%, 48%, and 8% of the CSA/MMF group vs. 16%, 36%, and 12% of the CSA/SRL group vs. 38%, 24% and 6% of the TAC/MMF group vs. 14%, 25% and 12% of the TAC/SLR group (IF/TA: CSA/MMF vs. CSA/SRL and TAC/SRL; p=0.04, HTN: CSA/MMF vs. TAC/MMF and TAC/SRL; p=0.05, CNI toxicity: TAC/SRL and CSA/SRL vs. TAC/MMF; p=0.05). Five-year patient and graft survival rates were 82% and 60% in the CSA/MMF group, 82% and 60% in the CSA/SRL group, 84% and 62% in the TAC/MMF group, and 82% and 64% in the TAC/SRL group (p=0.9). Serum creatinine levels and creatinine clearances at 5 years were comparable among the groups. Our data show that the rates of CAR and SCAR in the first year post-transplant were significantly lower in the CSA/SRL and TAC/SRL groups and that cumulative CAI rates due to IF/TA and HTN at 5 years were significantly lower in the TAC/MMF, TAC/SRL, and CSA/SRL groups than in the CSA/MMF group. Despite significant differences in the incidences of CAR and SCAR and prevalence of different types of CAI at 5 years, renal function and patient and graft survival rates at 5 years were comparable among kidney recipients maintained on 4 different immunosuppression protocols without long-term steroid therapy.     

Switch to a Sirolimus‐Based Immunosuppression in Long‐Term Renal Transplant Recipients: Reduced Rate of (Pre‐)Malignancies and Nonmelanoma Skin Cancer in a Prospective,Randomized, Assessor‐Blinded,Controlled Clinical Trial

Renal transplant recipients (RTR) have a 50–200‐fold higher risk for nonmelanoma‐skin cancer (NMSC) causing high rates of morbidity and sometimes mortality. Cohort‐studies gave evidence that a sirolimus‐based immunosuppression may inhibit skin tumor growth. This single‐center, prospective, assessor‐blinded, randomized trial investigated if switching to sirolimus treatment inhibits the progression of premalignancies and moreover how many new NMSC occur compared to continuation of the original immunosuppressive therapy. Forty‐four RTR (mean age 59.9 years, mean duration of immunosuppression 229.5 months) with skin lesions were randomized to sirolimus or continuation of their original immunosuppression. Blinded dermatological assessment at month 6 and 12 by the same dermatologist evaluated the clinical change compared to baseline. Biopsy was performed in suspected malignancy. Already the 6‐month‐assessment showed significant superiority of sirolimus‐therapy: a stop of progression, even regression of preexisting premalignancies (p < 0.0005). This effect was increased at month 12 (p < 0.0001). Nine patients developed histologically confirmed NMSC: one in the sirolimus group, eight in the control group, p = 0.0176. Sirolimus‐based immunosuppression in RTR, even when established many years after transplantation, can delay the development of premalignancies, induce regression of preexisting lesions and decelerate the incidence of new NMSC.     

Predictors of Success in Conversion from Calcineurin Inhibitor to Sirolimus in Chronic Allograft Dysfunction

Chronic allograft dysfunction (CAD) is a major cause of graft loss in long-term kidney transplant recipients. To identify predictors of successful conversion from calcineurin inhibitor (CNI) to sirolimus (SRL) we investigated 59 renal transplant patients with CAD without histological signs of acute rejection. They received 12-15 mg SRL once, then 4-5 mg/day, target trough level 8-12 ng/mL. CNI dose was reduced by 50% simultaneously, and withdrawn at 1-2 months. Concomitant immunosuppression remained unchanged. After 1 year patient survival was 100% and graft survival 92%. In responders (54%) creatinine improved (2.75 +/- 0.75 to 2.22 +/- 0.64 mg/dL; p < 0.01). In nonresponders (46%) creatinine deteriorated (3.15 +/- 1.02 to 4.44 +/- 1.60 mg/dL; p < 0.01). Baseline renal function did not differ, however, baseline proteinuria (519 +/- 516 vs. 1532 +/- 867 mg/day, p < 0.01), histological grade of chronic allograft nephropathy (CAN) (1.2 +/- 0.5 vs. 1.9 +/- 0.6; p < 0.01), grade of vascular fibrous intimal thickening (1.2 +/- 0.7 vs. 1.7 +/- 0.7; p = 0.048) and number of acute rejections before conversion (0.73 +/- 0.69 vs. 1.27 +/- 0.96; p < 0.05) differed significantly between responders and nonresponders. In a multivariate analysis low proteinuria was the only independent variable. Proteinuria below 800 mg/day has a positive predictive value of 90%. Proteinuria at conversion below 800 mg/day is the only independent predictor for positive outcome in conversion from CNI to SRL in CAD.     

Outcomes of Pediatric Kidney Transplantation in Recipients of a Previous Non‐Renal Solid Organ Transplant

Children who receive a non‐renal solid organ transplant may develop secondary renal failure requiring kidney transplantation. We investigated outcomes of 165 pediatric kidney transplant recipients who previously received a heart, lung, or liver transplant using data from 1988 to 2012 reported to the United Network for Organ Sharing. Patient and allograft survival were compared with 330 matched primary kidney transplant (PKT) recipients. Kidney transplantation after solid organ transplant (KASOT) recipients experienced similar allograft survival: 5‐ and 10‐year graft survival was 78% and 60% in KASOT recipients, compared to 80% and 61% in PKT recipients (p = 0.69). However, KASOT recipients demonstrated worse 10‐year patient survival (75% KASOT vs. 97% PKT, p < 0.001). Competing risks analysis indicated that KASOT recipients more often experienced graft loss due to patient death (p < 0.001), whereas allograft failure per se was more common in PKT recipients (p = 0.01). To study more recent outcomes, kidney transplants performed from 2006 to 2012 were separately investigated. Since 2006, KASOT and PKT recipients had similar 5‐year graft survival (82% KASOT vs. 83% PKT, p = 0.48), although 5‐year patient survival of KASOT recipients remained inferior (90% KASOT vs. 98% PKT, p < 0.001). We conclude that despite decreased patient survival, kidney allograft outcomes in pediatric KASOT recipients are comparable to those of PKT recipients.     

Sirolimus vs mycophenolate mofetil (MMF) in primary combined pancreas and kidney transplantation. Results of a long‐term prospective randomized study

The study was intended to compare pancreas graft survival rates in two groups of pancreas and kidney transplant recipients prospectively randomized to treatment either with sirolimus or MMF. From 2002 to 2013, 238 type 1 diabetic recipients with end‐stage kidney disease were randomized 1:1 to sirolimus or MMF treatment. Noncensored pancreas survival at 5 years was 76.4 and 71.6% for sirolimus and MMF groups, respectively (P > .05). Death‐censored pancreas survival was better in the sirolimus group (P = .037). After removal of early graft losses pancreas survival did not differ between groups (MMF 83.1% vs sirolimus 91.6%, P = .11). Nonsignificantly more grafts were lost due to rejection in the MMF group (10 vs 5; P = .19). Cumulative patient 5‐year survival was 96% in the MMF group and 91% in the sirolimus group (P > .05). Five‐year cumulative noncensored kidney graft survival rates did not statistically differ (85.6% in the sirolimus group and 88.8% in MMF group). Recipients treated with MMF had significantly more episodes of gastrointestinal bleeding (7 vs 0, P = .007). More recipients in the sirolimus group required corrective surgery due to incisional hernias (21 vs 12, P = .019). ClinicalTrials No.: NCT 03582878.     

De Novo Kidney Transplantation Without Use of Calcineurin Inhibitors Preserves Renal Structure and Function at Two Years

We performed a randomized prospective trial comparing calcineurin inhibitor (CNI)-free to CNI-based immunosuppression to determine the impact on renal function, structure and gene expression. Sixty-one kidney recipients treated with basiliximab mycophenolate mofetil (MMF) and prednisone (P) were randomly assigned to concentration-controlled sirolimus or cyclosporine. Two years post-transplant 55 patients underwent renal function studies, 48 (87%) underwent transplant biopsies; all classified by Banff scoring and 41 by DNA microarrays. Comparing sirolimus/MMF/P to cyclosporine/MMF/P there was a significantly lower serum creatinine (1.35 vs. 1.81 mg/dL; p = 0.008), higher Cockroft-Gault glomerular filtration rate (GFR) (80.4 vs. 63.4 mL/min; p = 0.008), iothalamate GFR (60.6 vs. 49.2 mL/min; p = 0.018) and Banff 0 (normal) biopsies (66.6 vs. 20.8%; p = 0.013). Regression analysis of calculated GFRs from 1 to 36 months yielded a positive slope for sirolimus of 3.36 mL/min/year, and a negative slope for cyclosporine of -1.58 mL/min/year (p = 0.008). Gene expression profiles from kidneys with higher Banff chronic allograft nephropathy (CAN) scores confirmed significant up-regulation of genes responsible for immune/inflammation and fibrosis/tissue remodeling. At 2 years the sirolimus-treated recipients have better renal function, a diminished prevalence of CAN and down-regulated expression of genes responsible for progression of CAN. All may provide for an alternative natural history with improved graft survival.     

Posttransplantation Hypomagnesemia and Its Relation with Immunosuppression as Predictors of New-Onset Diabetes after Transplantation

New-onset diabetes after transplantation (NODAT) is a frequent complication and has an impact on patient and graft survival. Hypomagnesemia is common in both renal transplant recipients and in diabetics. This study examines the relationship between hypomagnesemia, NODAT and the type of immunosuppression in renal transplant recipients.
We conducted a retrospective single-center analysis (2002–2008) in order to assess NODAT the first year posttransplantation as defined by American Diabetes Association criteria. Serum magnesium (Mg) levels were defined as the median of all Mg levels registered during the first month posttransplantation.
Patients with NODAT (N = 75; 29.5%) versus non-NODAT had lower Mg levels (p < 0.001). Patients with an Mg level < versus ≥1.9 mg/dL showed a faster development of NODAT (log-rank p < 0.001). Mg levels were lower in patients on calcineurin inhibitors (CNI) versus no CNI patients (p < 0.001). Mg levels, albumin, BMI, triglycerides, posttransplantation hyperglycemia, tacrolimus levels and the use of sirolimus were predictors of NODAT in the multivariate analysis.
Hypomagnesemia was an independent predictor of NODAT in renal transplant recipients. We confirm that the use of CNI is associated with NODAT, but, to a large extent, this effect seems attributable to the induction of hypomagnesemia. After adjustment for Mg, sirolimus was also associated with NODAT.     

Five‐Year Results of a Randomized Trial Comparing De Novo Sirolimus and Cyclosporine in Renal Transplantation: The Spiesser Study

Calcineurin inhibitors improve acute rejection rates and short‐term graft survival in renal transplantation, but their continuous use may be deleterious. We evaluated the 5‐year outcomes of sirolimus (SRL) versus cyclosporine (CsA) immunosuppressive treatment. This observational study was an extension of the SPIESSER study where deceased donor kidney transplant recipients were randomized before transplantation to a SRL‐ or CsA‐based regimen and followed up 1 year. Data from 131 (63 SRL, 68 CsA) out of 133 patients living with a functional graft at 1 year were collected retrospectively at 5 years posttransplant. Seventy percent of CsA patients versus 54% of SRL patients were still on the allocated treatment at 5 years (p = 0.091), most discontinuations in each group being due to safety issues. In intent‐to‐treat, mean MDRD eGFR was higher with SRL: 54.2 versus 45.3 mL/min with CsA (p = 0.019); SRL advantage was greater in on‐treatment analyses. There were no differences for patient survival (p = 0.873), graft survival (p = 0.121) and acute rejection (p = 0.284). Adverse events were more frequent with SRL (80% vs. 60%, p = 0.015). Results confirmed the high SRL discontinuation rate due to adverse events. Nevertheless, a benefit was evidenced on renal function in patients (more than 50%) still on treatment at 5 years.     

De novo sirolimus-based regimen in Thai renal transplant recipients

BACKGROUND: Calcineurin inhibitor (CNI) toxicity is a common cause of chronic allograft nephropathy. Although de novo sirolimus (SRL) with CNI minimization may provide better graft function, studies in Asian recipients are lacking. AIM: We sought to determine the 1-year outcomes of renal transplant patients who received a de novo SRL-based regimen with CNI minimization. PATIENTS AND METHODS: A single-center, prospective study of de novo SRL-based, reduced-dose cyclosporine regimen was performed from 2004 to 2007. The control group was a historical cohort of a cyclosporine-based regimen (cyclosporine, prednisolone, and mycophenolate mofetil). The 1-year outcome parameters included renal function, rate of acute rejection, biopsy-proven CNI toxicity, graft and patient survivals. RESULTS: The SRL-based regimen achieved 100% 1-year graft and patient survivals. The renal function was comparable between the SRL-based and CNI-based regimens (serum creatinine 1.32 +/- 0.45 and 1.45 +/- 0.43 mg/dL; P = .27). The rate of biopsy-proven acute rejection was comparable (9.5% and 13%; P = .68). The SRL-based regimen had a higher rate of biopsy-proven CNI toxicity (28.5% and 9.7%; P = .03). CONCLUSIONS: De novo SRL-based regimen with CNI minimization provides excellent transplant outcomes. The strategy to minimize or withdraw CNIs may achieve excellent graft function. A prospective study targeting lower CNI trough levels in Asian transplant recipients is required.     

A prospective study of rapid corticosteroid elimination in simultaneous pancreas-kidney transplantation: comparison of two maintenance immunosuppression protocols: tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus

BACKGROUND: We examined the feasibility of rapid corticosteroid elimination in simultaneous pancreas kidney transplantation. METHODS: Forty consecutive simultaneous pancreas-kidney (SPK) transplant recipients were enrolled in a prospective study in which antithymocyte globulin induction and 6 days of corticosteroids were administered along with tacrolimus and MMF (n=20) or tacrolimus and sirolimus (n=20). Mean+/-SD follow-up for recipients receiving tacrolimus/MMF and tacrolimus/sirolimus were 12.7+/-3.9 and 13.4+/-2.9 months, respectively. Patient and graft survival, and rejection rates were compared to an historical control group (n=86; mean follow-up 41.5+/-15.4 months) of SPK recipients that received induction and tacrolimus, MMF, and corticosteroids. RESULTS: Demographic characteristics of recipient and donor variables were similar among all groups. The 1-year actuarial patient, kidney, and pancreas survival rates in the 40 SPK transplant recipients with rapid corticosteroid elimination were 100, 100, and 100%, respectively. In the historical control group the 1-year actual patient, kidney, and pancreas survival rates were 96.5, 93.0, and 91.9%, respectively. The 1-year rejection-free survival rate recipients in the rapid steroid elimination group collectively was 97.5 vs 80.2% in the historical control group (P=0.034). At 6 and 12 months posttransplant the serum creatinine values remained stable in all groups. CONCLUSIONS: We conclude that chronic corticosteroid exposure is not required in SPK transplant recipients receiving antithymocyte globulin induction and maintenance immuno-suppression consisting of either tacrolimus and mycophenolate mofetil or tacrolimus and sirolimus.     

Stable kidney function in the second decade after kidney transplantation while on cyclosporine-based immunosuppression

BACKGROUND: Calcineurin inhibitors (CNIs) have been the mainstay of immunosuppressive protocols in kidney transplantation over the past 20 years. However, in some recipients, the adverse effects of CNIs contribute to chronic allograft nephropathy and death with function--the two leading causes of late graft loss. Other recipients maintain stable graft function. METHODS: We studied the impact of continuing CNI-based immunosuppression in the second decade after kidney transplantation. From 1984 through 1996, a total of 1,263 patients underwent a primary kidney transplant at the University of Minnesota and received cyclosporine-based immunosuppression. Antibody induction was used only in deceased donor recipients. RESULTS: The actuarial 20-year patient survival rate was 38%; graft survival, 30%; and death-censored graft survival, 60%. The annual mean serum creatinine level for recipients whose grafts survived > or =1 year remained stable, although recipients with a history of > or =1 acute rejection episode had a higher serum creatinine level vs. recipients who were rejection-free. The annual mean calculated creatinine clearance was also stable over time. In addition, for recipients who were acute rejection-free, chronic allograft nephropathy/chronic rejection was only responsible for 9% of graft losses. CONCLUSIONS: Our study suggests that some kidney transplant recipients tolerate long-term CNI-based immunosuppression with stable creatinine levels. Identifying certain recipients' predisposition to CNI toxicity and individualizing immunosuppressive therapy may be important in order to improve long-term kidney function, while simultaneously preserving low short-term acute rejection rates.     

Clinical Significance of Pretransplant Donor‐Specific Antibodies in the Setting of Negative Cell‐Based Flow Cytometry Crossmatching in Kidney Transplant Recipients

Antibodies to donor‐specific HLA antigens (donor‐specific antibodies [DSA]) detected by single‐antigen bead (SAB) analysis prior to kidney transplant have been associated with inferior graft outcomes. However, studies of pretransplant DSA, specifically in the setting of a negative flow cytometry crossmatch (FCXM) without desensitization therapy, are limited. Six hundred and sixty kidney and kidney–pancreas recipients with a negative pretransplant FCXM from September 2007 to August 2012 without desensitization therapy were analyzed with a median follow‐up of 4.2 years. All patients underwent cell‐based FCXM and SAB analysis on current and historic sera prior to transplantation. One hundred and sixty‐two patients (24.5%) had DSA detected prior to transplant. One‐year acute rejection rates were similar in DSA‐positive versus DSA‐negative patients (15.4% vs. 11.4%, respectively; p = 0.18) and were higher in those with DSA mean fluorescence intensity (MFI) greater than or equal to 3000 in multivariable analysis (p = 0.046). The estimated glomerular filtration rate (eGFR) at 3 and 4 years was lower in the DSA(+) versus the DSA(?) group (p = 0.050 at 3 years) without an impact on 5‐year death‐censored graft survival (89.0% vs. 90.6%, respectively; p = 0.53). Timing (current or historic) of DSA detection did not alter these findings. In conclusion, pretransplant DSA in the setting of a negative FCXM confers minimal immunologic risk in the intermediate term, does not necessitate desensitization therapy and should not represent a barrier to renal transplant.     

Long‐term results after conversion from calcineurin inhibitors to sirolimus in renal transplant patients

Martinez‐Mier G, Avila‐Pardo SF, Mendez‐Lopez MT, Budar‐Fernandez LF. Long‐term results after conversion from calcineurin inhibitors to sirolimus in renal transplant patients.
Clin Transplant 2010: 24: 467–473.
© 2009 John Wiley & Sons A/S. Abstract: Background: Calcineurin inhibitors (CNI) toxicity is one of the contributing factors for the development and progression of chronic allograft dysfunction (CAD). Conversion to sirolimus (SRL) from CNI improves renal function kidney in transplant recipients. Methods: A retrospective review from patients abruptly converted from CNI to SRL over a three yr period is reported. Results: Thirty‐nine patients were converted 55.2 ± 58 months after renal transplantation. 24 month patient and graft survival was 100% and 92%. Acute rejection incidence was 7.6%. Overall, serum creatinine (SCr) and Cockcroft–Gault creatinine clearance (CGCrCl) improved. In responders, SCr improved from 2.48 ± 0.8 to 1.94 ± 0.8 mg/dL (p < 0.05) CGCrCl improved from 37.8 ± 17.4 to 51.9 ± 23.8 mL/min at two years. An increase in proteinuria was observed from conversion to month 12 in responders (189.4 ± 512.8 to 488.3 ± 890.6 mg/day, p < 0.05) and from conversion to month six in non‐responders (1179.4 ± 2001.1 to 2357 ± 4172.9 mg/day, p < 0.05). Low proteinuria had positive predictive value for renal response after conversion. Conclusion: Conversion from CNI to SRL with CAD is associated with improved renal function with an increase in proteinuria. Low proteinuria is a possible positive predictive factor for successful conversion.     

Rejection after conversion to a proliferation signal inhibitor in chronic heart transplantation

We sought to determine the incidence, risk factors, and consequences of acute rejection (AR) after conversion from a calcineurin inhibitor (CNI) to a proliferation signal inhibitor (PSI) in maintenance heart transplantation. Relevant clinical data were retrospectively obtained for 284 long‐term heart transplant recipients from nine centers in whom CNIs were replaced with a PSI (sirolimus or everolimus) between October 2001 and March 2009. The rejection rate at one yr was 8.3%, stabilizing to 2% per year thereafter. The incidence rate after conversion (4.9 per 100 patient‐years) was significantly higher than that observed on CNI therapy in the pre‐conversion period (2.2 per 100 patient‐years). By multivariate analysis, rejection risk was associated with a history of late AR prior to PSI conversion, early conversion (<5 yr) after transplantation and age <50 yr at the time of conversion. Use of mycophenolate mofetil was a protective factor. Post‐conversion rejection did not significantly influence the evolution of left ventricular ejection fraction, renal function, or mortality during further follow‐up. Conversion to a CNI‐free immunosuppression based on a PSI results in an increased risk of AR. Awareness of the clinical determinants of post‐conversion rejection could help to refine the current PSI conversion strategies.