Incidence of BK with Tacrolimus Versus Cyclosporine and Impact of Preemptive Immunosuppression Reduction

Our purposes were to determine the incidence of BK viruria, viremia or nephropathy with tacrolimus (FK506) versus cyclosporine (CyA) and whether intensive monitoring and discontinuation of mycophenolate (MMF) or azathioprine (AZA), upon detection of BK viremia, could prevent BK nephropathy. We randomized 200 adult renal transplant recipients to FK506 (n = 134) or CyA (n = 66). Urine and blood were collected weekly for 16 weeks and at months 5, 6, 9 and 12 and analyzed for BK by polymerase chain reaction (PCR). By 1 year, 70 patients (35%) developed viruria and 23 (11.5%) viremia; neither were affected independently by FK506, CyA, MMF or AZA. Viruria was highest with FK506-MMF (46%) and lowest with CyA-MMF (13%), p = 0.005. Viruria >/= 9.5 log(10) copies/mL was associated with a 3-fold increased risk of viremia and a 13-fold increased risk of sustained viremia. After reduction of immunosuppression, viremia resolved in 95%, without increased acute rejection, allograft dysfunction or graft loss. No BK nephropathy was observed. Choice of calcineurin inhibitor or adjuvant immunosuppression, independently, did not affect BK viruria or viremia. Viruria was highest with FK506-MMF and lowest with CyA-MMF. Monitoring and preemptive withdrawal of immunosuppression were associated with resolution of viremia and absence of BK nephropathy without acute rejection or graft loss.     

Conversion From Immediate-Release Tacrolimus to Prolonged-Release Tacrolimus in Stable Heart Transplant Patients: A Retrospective Study

BackgroundLifelong adherence with post-transplant immunosuppression is challenging, with nonadherence associated with greater acute rejection (AR) risk.MethodsThis retrospective study evaluated conversion from immediate-release tacrolimus (IRT) to prolonged-release tacrolimus (PRT), between January 2008 and December 2012 in stable adult heart transplant recipients. Cumulative incidence rate (IR) of AR and infection pre- and postconversion, safety, tacrolimus dose and trough levels, concomitant immunosuppression, and PRT discontinuation were analyzed (intention-to-treat population).ResultsOverall, 467 patients (mean age, 59.3 [SD, 13.3] years) converted to PRT at 5.1 (SD, 4.9) years post transplant and were followed for 3.4 (SD, 1.5) years. During the 6 months post conversion, 5 patients (1.1%; 95% CI, 0.35%–2.48%) had an AR episode and IR was 2.2/100 patient-years (95% CI, 0.91–5.26). Incidence of rejection preconversion varied by time from transplant to conversion. Infection IR was similar post- and preconversion (9.2/100 patient-years [95% CI, 7.4–11.3] vs 10.6/100 patient-years [95% CI, 8.8–12.3], respectively; P = .20). Safety variables remained similar post conversion. The IR of mortality/graft loss was 2.3/100 patient-years (95% CI, 1.7–3.1).ConclusionsConversion from IRT to PRT in heart transplant recipients in Spain was associated with no new safety concerns and appropriate immunosuppressive effectiveness.     

Mycophenolate Mofetil/Sirolimus Compared to Other Common Immunosuppressive Regimens in Kidney Transplantation

We evaluated outcomes with the sirolimus (SRL) and mycophenolate mofetil (MMF) combination regimen (SRL/MMF) in solitary kidney transplant recipients transplanted between 2000 and 2005 reported to the Scientific Registry of Renal Transplant Recipients. Three-and-a-half percent received SRL/MMF (n = 2040). Six-month acute rejection rates were higher with SRL/MMF (SRL/MMF: 16.0% vs. other regimens: 11.2%, p < 0.001). Overall graft survival was significantly lower on SRL/MMF. SRL/MMF was associated with twice the hazard for graft loss (AHR = 2.0, 95% C.I., 1.8, 2.2) relative to TAC/MMF, also consistent in both living donor transplants (AHR = 2.4, 95% C.I., 1.9, 2.9) and expanded criteria donor transplants (AHR = 2.1, 95% C.I., 1.7-2.5). Among deceased donor transplants, DGF rates were higher in the SRL/MMF cohort (47% vs. 27%, p < 0.001). However, adjusted graft survival was also significantly inferior with SRL/MMF in DGF-free patients (AHR = 1.9, 95% C.I., 1.6-2.3). In analyses restricted to patients who remained on the discharge regimen at 6 months posttransplant, conditional graft survival in deceased donor transplants was significantly lower with SRL/MMF compared to patients on TAC/MMF or CsA/MMF regimens at 5 years posttransplant (64%, 78%, 78%, respectively, p = 0.001) and across all patient subgroups. In conclusion, SRL/MMF is associated with inferior renal transplant outcomes compared with other commonly used regimens.     

Cyclosporine versus Tacrolimus Treated Liver Transplant Recipients with Chronic Hepatitis C: Outcomes Analysis of the UNOS/OPTN Database

Recurrent hepatitis C virus (HCV) remains a problematic cause of morbidity and mortality for liver transplant patients. Immunosuppression including calcineurin‐inhibitors has been implicated in the acceleration of recurrent HCV. Recent studies suggest that outcomes may be better with cyclosporine (CSA‐ME) compared to tacrolimus (TAC), but the data are inconclusive. We retrospectively analyzed data received from the United Network for Organ Sharing on 8809 chronic HCV liver transplant recipients receiving either cyclosporine microemulsion (CSA‐ME) or tacrolimus (TAC) as maintenance immunosuppression prior to discharge. We analyzed patient death, graft failure, failure due recurrent disease and acute cellular rejection (ACR) for CSA‐ME versus TAC treated patients. Three‐year unadjusted patient and graft survival rates were 76.8% and 71.5%, respectively, in the CSA‐ME group versus 79.9% and 75.0% in the TAC group. Propensity score‐adjusted results suggest CSA‐ME treated patients are at increased risk of patient death and graft failure [Hazards ratio (HR) = 1.17; 95% CI = 1.01–1.36 and HR = 1.19; 95% CI = 1.04–1.35, respectively] and biopsy‐confirmed AR (HR = 2.03; 95% CI = 1.54–2.67) compared to TAC treated patients. These results provide evidence to reconsider the targeted administration of CSA‐ME to HCV‐infected liver transplant recipients.     

Pediatric Lung Transplant Outcomes Based on Immunosuppressive Regimen at Discharge: Retrospective Cohort Study Using Real-World Evidence From the US Scientific Registry of Transplant Recipients

BackgroundThis retrospective analysis of the US Scientific Registry of Transplant Recipients was undertaken to obtain real-world evidence concerning the efficacy and safety of tacrolimus-based immunosuppression in pediatric lung transplant recipients to support a supplemental New Drug Application.MethodsOverall, 725 pediatric recipients of a primary deceased-donor lung transplant between January 1, 1999, and December 31, 2017, were followed for up to 3 years post-transplant based on an immunosuppressive regimen at hospital discharge: immediate-release tacrolimus (TAC)+mycophenolate mofetil (MMF), TAC+azathioprine (AZA), cyclosporine (CsA)+MMF, or CsA+AZA. The primary outcome was the composite endpoint of graft failure or death (all-cause) at 1 year post-transplant, calculated by Kaplan–Meier analysis.ResultsThe use of TAC+MMF increased over time. During 2010 to 2017, 91.7% of pediatric lung transplant recipients were receiving TAC+MMF at the time of discharge. The proportion of recipients continuing their discharge regimen at 1 year post-transplant was 83.7% with TAC+MMF and 40.4% to 59.7% with the other regimens. Cumulative incidence of the composite endpoint of graft failure or death at 1 year post-transplant was 7.7% with TAC+MMF, 13.9% with TAC+AZA, 8.9% with CsA+MMF, and 9.1% with CsA+AZA. There was no significant difference in the risk of graft failure or death at 1 year post-transplant between groups from 1999 to 2005 (the only era when adequate numbers on each regimen allowed statistical comparison). No increase in hospitalization for infection or malignancy was seen with TAC+MMF.ConclusionThe real-world evidence from the US database of transplant recipients supported the Food and Drug Administration's approval of tacrolimus-based maintenance immunosuppression in pediatric lung transplant recipients.     

Sirolimus in Combination with Tacrolimus Is Associated with Worse Renal Allograft Survival Compared to Mycophenolate Mofetil Combined with Tacrolimus

Cyclosporine (CsA) nephrotoxicity is enhanced by sirolimus (SRL). Tacrolimus is perceived to be less nephrotoxic than CsA, and therefore, CsA has been largely replaced by tacrolimus (TAC) when calcineurin inhibitors are used with SRL. We analyzed 44 915 adult renal transplants in the Scientific Renal Transplant Registry (SRTR) from 2000 to 2004. Three thousand five hundred twenty-four (7.8%) patients received a baseline immunosuppressive regimen of TAC/SRL, with an inferior overall (log-rank p<0.001) and death-censored graft survival (p<0.001) as compared to TAC/MMF (N=27 007). This effect was confirmed in multivariate Cox models; the adjusted hazard ratio (AHR) for overall graft loss with TAC/SRL was 1.47 (95% CI=1.32, 1.63) and for CsA/SRL 1.38 (95% CI=1.20, 1.59) relative to TAC/MMF. These effects were most apparent in high-risk transplants. Six-month acute rejection rates were low (11.5-12.6%) and not different between groups. In summary, national data indicate that TAC/SRL as compared to TAC/MMF is associated with significantly worse renal allograft survival in all subgroups of patients and, in particular, higher-risk transplants. These results have to be interpreted in the context of the inherent limitations of any retrospective database analysis and evaluated in context with data from prospective clinical trials.     

Effect of mycophenolate mofetil on long-term outcomes in African american renal transplant recipients

African American renal transplant recipients have poorer graft survival. A study using the United States Renal Data Registry documented an improvement in graft survival for patients who took mycophenolate mofetil (MMF) compared with azathioprine (AZA). This analysis did not address the impact of MMF on African American renal transplant recipients. The present study aimed to quantify potential beneficial effects of MMF therapy on long-term renal allograft survival in African Americans. With the use of the United States Renal Data Registry, all adult Caucasian and African American patients who had received a primary renal transplant between 1988 and 1997 were analyzed by Kaplan-Meier analysis and Cox proportional hazard models. Primary study end points were death with a functioning graft and graft failure censored for death. A total of 57,926 patients were studied. For African Americans, 3-yr patient survival was 96.3 versus 93.2% (P<0.001) for MMF and AZA, respectively. Three-yr death-censored graft survival for African Americans was 85.8 versus 75.1% (P<0.001) for MMF and AZA, respectively. For Caucasians, 3-yr patient survival was 97.3 versus 93.2% for MMF and AZA, respectively. Three-yr death-censored graft survival for Caucasians was 90.1 versus 86.4% (P<0.001) for MMF and AZA, respectively. By multivariate analysis, MMF was associated with a significant reduction in the relative risk for all study end points in African Americans. MMF therapy is associated with both improved patient and death-censored graft survival in African American renal transplant recipients. This benefit is comparable to the benefit of MMF in Caucasian renal transplant recipients.     

Polyomavirus nephropathy after renal transplantation: a single centre experience

BACKGROUND: Polyomavirus associated nephropathy (PVN) in renal transplant recipients has been observed with increasing frequency recently and has emerged as a cause of allograft failure linked to highly potent new immunosuppressive regimens containing tacrolimus or mycophenolate mofetil (MMF). METHODS: Polyomavirus associated nephropathy was identified in nine out of 182 patients who received renal transplantation between October 1998 and July 2003. PVN was confirmed by allograft biopsy. The clinical records of these nine patients were reviewed, as were all of the allograft biopsies. Electron microscopy was performed in all nine cases. After the diagnosis of PVN, maintenance immunosuppression was reduced. The clinical course and outcome of the PVN patients were reviewed in relation to manipulation of immunosuppressive agents. RESULTS: There were nine cases of PVN in renal transplant recipients and the incidence of PVN was 4.9%. All patients with PVN were under triple immunosuppression comprising tacrolimus and MMF. The mean time to a diagnosis of PVN was 7.8 months after transplantation. Three of the nine patients received antirejection therapy prior to PVN. Seven out of nine PVN patients presenting acute allograft dysfunction were initially treated with high-dose intravenous steroid pulse or OKT3 before reduction of the immunosuppression. After reduction of the immunosuppression, seven patients stabilized their renal function. Two (22%) lost their grafts due to persistent PVN and chronic rejection. Two (22%) patients later developed acute rejection after reduction of the immunosuppression. CONCLUSION: PVN can cause allograft dysfunction and graft loss. Renal allograft recipients who are at risk of PVN should be routinely screened with urine cytology and quantitative measurements of viral load in the blood, particularly patients who had graft dysfunction. Early diagnosis and judicious alteration of immunosuppressive agents might permit a superior prognosis and reduce the graft loss from PVN in renal transplant recipients.     

Cyclosporin versus Tacrolimus as Primary Immunosuppressant After Liver Transplantation: A Meta-Analysis

A systematic review of randomized clinical trials (RCT) was undertaken to evaluate the beneficial and harmful effects of immunosuppression with cyclosporin versus tacrolimus for liver transplanted patients. MEDLINE, EMBASE, Cochrane Central and Hepato-Biliary Group Controlled Trials Registers were searched. Using fixed and random effects model, relative risk (RR), values <1 favoring tacrolimus, with 95% confidence intervals (CI) were calculated. Of 717 potentially relevant references, 16 RCTs were eligible for inclusion. Mortality and graft loss at 1 year were significantly reduced in tacrolimus-treated recipients (Death: RR 0.85, 95% CI 0.73-0.99; graft loss: RR 0.73, 95% CI 0.61-0.86). Tacrolimus reduced the number of recipients with acute rejection (RR 0.81, 95% CI 0.75-0.88) and steroid-resistant rejection (RR 0.54, 95% CI 0.47-0.74) in the first year. Lymphoproliferative disorder or dialysis rates were not different but more de novo diabetes (RR 1.38, 95% CI 1.01-1.86) occurred with tacrolimus. More patients stopped cyclosporin than tacrolimus (RR 0.57, 95% CI 0.49-0.66). Treating 100 recipients with tacrolimus instead of cyclosporin would avoid rejection and steroid-resistant rejection in nine and seven patients respectively, graft loss and death in five and two patients respectively, but four additional patients would develop diabetes after liver transplantation.     

Impact of Immunosuppressive Medication on the Risk of Renal Allograft Failure due to Recurrent Glomerulonephritis

Recurrent glomerulonephritis is a major problem in kidney transplantation but the role of immunosuppression in preventing this complication is not known. We used data from the United States Renal Data System to examine the effect of immunosuppressive medication on allograft failure due to recurrent glomerulonephritis for 41 272 patients undergoing kidney transplantation from 1990 to 2003. Ten-year incidence of graft loss due to recurrent glomerulonephritis was 2.6% (95% confidence interval [CI]: 2.3–2.8%). After adjusting for important covariates, the use of cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, sirolimus or prednisone was not associated with graft failure due to recurrent glomerulonephritis. There was no difference between cyclosporine and tacrolimus or between azathioprine and mycophenolate mofetil in the risk of graft failure due to recurrent glomerulonephritis. However, any change in immunosuppression during follow-up was independently associated with graft loss due to recurrence (adjusted hazard ratio 1.30, 95% CI: 1.06–1.58, p = 0.01). In patients with a pretransplant diagnosis of glomerulonephritis, the risk of graft loss due to recurrence was not associated with any specific immunosuppressive medication. The selection of immunosuppression for kidney transplant recipients should not be made with the goal of reducing graft failure due to recurrent glomerulonephritis.     

Albuminuria after renal transplantation: maintenance with sirolimus/low-dose tacrolimus vs. mycophenolate mofetil/high-dose tacrolimus

Maintenance immunosuppression with sirolimus (SRL) in renal transplantation has been associated with proteinuria. We report long-term outcomes of kidney transplant recipients maintained on steroid-free regimens, either SRL with low-dose tacrolimus (SRL/L-Tac) or mycophenolate mofetil (MMF) with high-dose tacrolimus (MMF/H-Tac). We conducted a case-matched study of 50 patients receiving MMF/H-Tac, matched 1:2 with 100 patients maintained on SRL/L-Tac. All patients were induced with rabbit antithymocyte globulin followed by early steroid withdrawal. Comparisons were made of patient and graft survival, graft function, acute rejection, and albuminuria. There were no significant differences between the SRL/L-Tac and MMF/H-Tac groups for patient survival, graft survival, occurrence of acute rejection, or graft function. There was no difference in the proportion of patients with albumin/creatinine ratio (ACR) ≥300 μg/mg (19% vs. 20%), but more patients in the SRL group were receiving renin-angiotensin system blocking agents (72% vs. 53%, p = 0.04). Only flushing the donor kidney with histidine-tryptophan-ketoglutarate solution (vs. UW solution) was predictive of albuminuria. Long-term outcomes are similar at our center for kidney transplant patients receiving either SRL/L-Tac or MMF/H-Tac. Although the occurrence of albuminuria was not different, significantly more SRL-treated patients were receiving antiproteinuric medications.     

A comparison of discharge immunosuppressive drug regimens in primary cadaveric kidney transplantation

BACKGROUND: Finding the best combination of immunosuppression is an important challenge in kidney transplantation. Current short-term (1- and 3-year) allograft survival is quite good, making it difficult to determine differences in therapeutic regimens without large sample sizes. Using data from the United Network for Organ Sharing/Organ Procurement and Transplantation Network database, the current study provides substantial statistical power to analyze the outcomes for different immunosuppressive regimens. METHODS: To compare the effects of four discharge regimens (cyclosporine and azathioprine [CYA+AZA], CYA and mycophenolate mofetil [MMF], tacrolimus [TAC]+AZA, and TAC+MMF) on long-term survival, a multivariate Cox regression analysis was conducted on 19246 primary cadaveric kidney transplants during 1995 to 1998. RESULTS: Compared with CYA+AZA, the combination of CYA+MMF was associated with a 10% reduced risk of graft loss (relative risk [RR] 0.90, 95% confidence limit [CL] 0.84-0.96, P<0.001), whereas TAC+AZA was associated with an 18% reduced risk (RR 0.82, 95% CL 0.67-1.005, P=0.06) and TAC+MMF with a 20% reduced risk of graft loss (RR 0.80, 95% CL 0.71-0.89, P<0.001). All three regimens benefited patients regardless of delayed graft function (DGF) or early acute rejection status. In addition, in the absence of DGF, the combinations of CYA+MMF, TAC+AZA, and TAC+MMF were associated with a reduced risk of mortality compared with CYA+AZA. CONCLUSIONS: The major finding of this study was improved graft and patient survival associated with TAC+MMF and CYA+MMF in patients with or without DGF or early acute rejection.     

Late,Severe, Noninfectious Diarrhea After Renal Transplantation: High-Risk Factors,Therapy, and Prognosis

Objective

Late severe noninfectious diarrhea in renal transplant recipients can lead to malnutrition and even graft loss. The purpose of this study was to evaluate risk factors associated with this condition and summarize therapy for these patients.

Methods

For more than 36 months we observed a cohort of 541 recipients who underwent kidney transplantation from January 2001 to June 2007. They were provided a calcineurin inhibitor (CNI) combined with mycophenolate mofetil (MMF). The four group includes a continuous cyclosporine (CsA); a preconversion to tacrolimus and a postconversion group as well as a continuous tacrolimus group. The rate of severe late noninfectious diarrhea was compared among the four groups. Risk factors were analyzed between the diarrhea and nondiarrhea cohorts. Clinical characteristics, efficacy, and safety were observed after modifying the immunosuppressive protocol for late severe noninfectious diarrhea recipients.

Results

Twenty-eight recipients presented with late sever noninfectious diarrhea. No patients displayed chronic diarrhea in the CsA (n = 145) or preconversion group (n = 95). The rate of diarrhea was 7.31% in the postconversion and 7.35% in the tacrolimus group. Using multivariate Cox proportional hazards analysis, factors associated with an increased risk of noninfectious diarrhea were cytochrome P450(CYP)3A5 *3/*3 type, chronic renal allograft dysfunction, and patient ingestion of Tripterygium wilfordii Hook F. All diarrheal recipients experienced weight loss, hypoalbuminia, and an increased serum creatinine. All affected patients underwent adjustment of the immunosuppressive regimen to achieve remission. Renal allograft survival in recipients with diarrhea was worse than that in nondiarrheal recipients receiving tacrolimus combined with MMF.

Conclusion

Tacrolimus with MMF increased the risk of late severe noninfectious diarrhea among renal transplant recipients compared with hosts treats with CsA plus MMF. The CYP3A5 *3/*3 type, chronic renal allograft dysfunction, and T wilfordii supplementation were high-risk factors for late diarrhea. Prompt adjustment of immunosuppression was an effective, feasible therapy for these patients.     

New immunosuppressive treatment in kidney transplantation

BACKGROUND: Mycophenolate mofetil (MMF) has been successfully introduced into clinical practice with evident benefits for renal transplant recipients. SUBJECTS AND METHODS: To evaluate some clinical results of MMF introduction, two groups of subjects underwent cadaveric renal transplants over the last 3 years and were retrospectively investigated. The first group (AZA group) contained 40 subjects (26 males and 14 females) on triple-drug therapy with steroids, cyclosporine and azathioprine (AZA). The second group (MMF group) contained 25 patients ( 19 males and 6 females) on the same regime with steroids and cyclosporine but MMF was administered as a third drug instead of AZA. The AZA group received renal transplant after a mean dialytic time of 32 +/- 19 months and the AZA group's dialytic time was 39.9 +/- 17 months. Clinical data, collected after a minimum 12 months observational period included a crude mortality rate and survival analysis recognized by Kaplan-Meyer curve, creatinine, creatinine clearance, rejection episodes and major clinical events such as infections and acute tubular necrosis. RESULTS: One subject died in each group. For kidney graft survival, Kaplan Meyer survival analysis showed a mean survival time of 1170.04 days in the AZA group vs 845 in the MMF group without statistical significance. Graft survival demonstrated 5:40 (12.5%) graft losses in the AZA group vs no kidney transplant loss in the MMF group (the only deceased patient had a well functioning kidney). The curve of graft cumulative proportion survival analysis demonstrated a more improved survival in the MMF group, but this difference did not reach a statistical significance (p = 0.07). Acute rejection episodes in the AZA group were 37.5% vs. 20% in the MMF group. In both groups, CMV infection was successfully treated with specific antiviral agents. CONCLUSIONS: MMF represents an important step towards induction and maintenance of immunosuppression. Our experience in a relatively small cohort investigated in a single center, demonstrates encouraging results regarding graft survival in comparison to those detected in conventional triple drug therapy. Surprisingly, in spite of stronger immunosuppressive treatment, the prevalence of CMV infections was not statistically different in the MMF versus the AZA group.     

Tacrolimus versus cyclosporin in renal transplantation in Italy: cost-minimisation and cost-effectiveness analyses

BACKGROUND: The economic impact of therapies has increasingly become part of the clinical decision-making process. Costs associated with kidney transplantation are substantial and economic evaluations are useful in identifying immunosuppressive regimens that yield optimal clinical and economic benefits. METHODS: Utilisation of health care resources during the first 6-months after renal transplantation was examined in 557 kidney transplant recipients participating in a European, multicentre, randomised, parallel group study that compared the efficacy and safety of a tacrolimus-based regimen versus a cyclosporin-microemulsion-based regimen. Cost-minimisation and cost-effectiveness analyses were conducted from an Italian hospital perspective, including direct medical costs only (e.g. medication, hospitalisation). RESULTS: The incidence of acute rejection was significantly lower in the tacrolimus group than in the cyclosporin microemulsion (ME) group (32.5% versus 51.3%; p<0.001). Patient and graft survival were similar in both treatment groups. Renal transplant recipients receiving tacrolimus-based immunosuppression had lower utilisation of health care resources and lower total costs per patient than cyclosporin-ME treated patients. When surviving patients with a rejection-free graft were analysed, tacrolimus therapy was cost-saving, since it was both more effective (18.8% difference in the incidence of acute rejection; 95%CI 10.7%-26.8%; p<0.001) and less costly than cyclosporin-ME based therapy (cost difference euro9918). The costs per patient with a functioning graft were euro2305, the costs per surviving patient were euro1892 lower in tacrolimus treated patients. Sensitivity analyses using the key cost-drivers (hospitalisation, study drug, and concomitant medication) found the cost advantage of tacrolimus was maintained. CONCLUSION: In the first 6 months after renal transplantation, tacrolimus-based therapy was less costly than cyclosporin-ME based therapy. When surviving patients with a rejection-free graft were considered, tacrolimus was the dominant therapy.     

The influence of mycophenolate mofetil versus azathioprine and mycophenolic acid pharmacokinetics on the incidence of acute rejection and infectious complications after renal transplantation

PURPOSE: The present retrospective study investigated the influence of mycophenolate mofetil (MMF) instead of azathioprine (AZA) as part of tacrolimus-based immunosuppression. Mycophenolic acid (MPA) pharmacokinetic (PK) parameters were used for associations with the incidence of acute rejection (AR) episodes and infectious complications after renal transplantation. METHODS: The 66 consecutive renal transplant recipients reported herein excluded ABO-incompatible transplants or cytomegalovirus (CMV)-seronegative recipients. The immunosuppressive regimen consisted of tacrolimus, steroids, and AZA 1-2 mg/kg/d in 22 patients (between February 1998 and December 2000) or MMF 2 g/d in 44 patients (since January 2001). CMV infection was defined as positive CMV-antigenemia. MPA PK was studied on day 28 after transplantation in 21 recipients. RESULTS: AR occurred in 13.6% of patients in the MMF group compared with 18.2% in the AZA group. The viral infection (CMV, varicella zoster virus, adenovirus hemorrhagic cystitis, and malignancy related to Epstein-Barr [EB] virus) rate was 22.7% in the MMF group and 0% in the AZA group (P = .015). There were no bacterial or fungal infections observed in the 2 groups. MMF dose per body weight was significantly lower among patients with AR than those without AR (25.1 vs 35.6 mg/kg; P = .026). There were no differences in MPA PK parameters between patients with and without viral infections. CONCLUSIONS: Patients treated with MMF required less treatment for AR, however, there were no significant differences. MMF dose per body weight may play an important role in the occurrence of AR. Although virus infections occurred in recipients treated with MMF, MPA PK did not influence the infectious complications after renal transplantation.     

Long-term efficacy and safety of a calcineurin inhibitor-free regimen in live-donor renal transplant recipients

Calcineurin inhibitor (CNI) nephrotoxicity is a major concern after renal transplantation. To investigate the safety and efficacy of a CNI-free immunosuppressive regimen, 132 live-donor renal transplant recipients were included in a prospective, randomized controlled trial. All patients received induction therapy with basiliximab and steroids. The patients were randomized to a maintenance immunosuppression regimen that included steroids, sirolimus, and either low-dose tacrolimus or mycophenolate mofetil (MMF). Over a mean follow-up period of approximately 5 yr, patient and graft survival did not significantly differ between the two maintenance regimens. Patient survival was 93.8% and 98.5% in the tacrolimus/sirolimus and MMF/sirolimus groups, respectively, and graft survival was 83% and 88%, respectively. However, the MMF/sirolimus group had significantly better renal function, calculated by Cockcroft-Gault, from the second year post-transplant until the last follow-up. In addition, this group was less likely to require a change in their primary immunosuppression regimen than the tacrolimus/sirolimus group (20.8% versus 53.8%, P = 0.001). The safety profile was similar between groups. In summary, after long-term follow-up, a CNI-free maintenance regimen consisting of sirolimus, MMF, and steroids was both safe and efficacious among low to moderate immunologic risk renal transplant recipients.     

Graft and Patient Survival in Kidney Transplant Recipients Selected for de novo Steroid-Free Maintenance Immunosuppression

Steroid-free regimen is increasingly employed in kidney transplant recipients across transplant centers. However, concern remains because of the unknown impact of such an approach on long-term graft and patient survival. We studied the outcomes of steroid-free immunosuppression in a population-based U.S. cohort of kidney transplant recipients. All adult solitary kidney transplant recipients engrafted between January 1, 2000 and December 31, 2006 were stratified according to whether they were selected for a steroid-free or steroid-containing regimen at discharge. Multivariate Cox regression models were used to estimate graft and patient survival. The impact of the practice pattern on steroid use at individual transplant centers was analyzed. Among 95 755 kidney transplant recipients, 17.2% were steroid-free at discharge (n = 16 491). Selection for a steroid-free regimen was associated with reduced risks for graft failure and death at 1 year (HR 0.78, 95% CI 0.72–0.85, and HR 0.73, 95% CI 0.65–0.82, respectively, p < 0.0001) and 4 years (HR 0.83, 95% CI 0.78–0.87, and HR 0.76, 95% CI 0.71–0.83, respectively, p < 0.0001). This association was mostly observed at individual centers where less than 65% of recipients were discharged on the steroid-containing regimen. De novo steroid-free immunosuppression as currently practiced in the United States appears to carry no increased risk of adverse clinical outcomes in the intermediate term.     

Six-year follow-up of azathioprine and mycophenolate mofetil use during the first 6 months of renal transplantation

Long-term follow-up examination to test whether therapy with mycophenolate mofetil (MMF) or azathioprine (AZA) during the first year translates into different graft or patient survival and graft function is important. Therefore, 6-year follow-up data of a group of 80 consecutive renal transplant recipients were analyzed. The first group of 40 patients was treated with AZA, cyclosporine and prednisone and the second group with MMF, cyclosporine and prednisone for the first 6 months. Graft failure rates were compared during follow-up. Creatinine, inverse slope of creatinine (delta/creatinine) and 24-hour proteinuria at 6 years post transplantation were compared. The Kaplan-Meier analyses for death-censored and non-censored graft failure showed no difference between the groups. Creatinine values at 6 years for the AZA Group were 139 +/- 36 micromol/l (95% CI 125.9-151.2 micromol/l) and for the MMF Group 149 +/- 52 micromol/l (95% CI 133.9-164.9 micromol/l). Delta/creatinine and 24-hour proteinuria at 6 years did not differ between the two groups. We conclude that an initial 6-month treatment with MMF as opposed to AZA reduced the early rejection rate, but did not result in superior long-term graft function or survival after 6 years of follow-up observation.     

The relative risk of overall graft loss and acute rejection among African American renal transplant recipients is attenuated with advancing age

Schold JD, Srinivas TR, Braun WE, Shoskes DA, Nurko S, Poggio ED. The relative risk of overall graft loss and acute rejection among African American renal transplant recipients is attenuated with advancing age.
Clin Transplant 2011: 25: 721–730. © 2010 John Wiley & Sons A/S. Abstract: Background: Graft loss rates are elevated among African American (AA) kidney transplant recipients. This may be attributable to immunological responses, socioeconomic disparities, comorbid conditions and access to care, but it is unclear whether risks are uniform in the AA population. Methods: We utilized multivariable models with the national SRTR database for adult recipients transplanted from 2000 to 2009 (n = 112 120) to investigate whether risks of graft loss, death and acute rejection between AAs and Caucasians vary with age. Results: Relative to Caucasians, AA recipients had significantly higher risk of overall graft loss among patients aged 18–49 (AHR = 1.37, 95% CI 1.30–1.43) but comparable risk among patients aged >65 (AHR = 1.04, 95% CI 0.96–1.13). Among recipients aged 18–34, AAs had higher risk of acute rejection (AOR = 1.33, 95% CI 1.12–1.57) but similar likelihood among recipients aged >65 (AOR = 0.94, 95% CI 0.75–1.17). Differences between race groups, as well as the relatively higher risks among younger AAs, were most pronounced following one yr post‐transplantation and diminished with presence of other risk factors. Conclusions: Elevated risks of overall graft loss and acute rejection are present among younger but not older AA kidney transplant recipients. These findings may have important implications for treatment decisions, follow‐up protocols and designation of “high‐risk” patients.