Safe conversion of mycophenolate mofetil to azathioprine in kidney transplant recipients with sirolimus-based immunosuppression

Aim:   Mycophenolate mofetil (MMF) is a powerful immunosuppressive drug with established efficacy and safety. The long-term use of MMF may bring increased risk of for infection and malignancy and also increased cost of transplantation. The search for minimization of immunosuppressive protocol has led to an open randomized clinical trial of conversion from MMF to azathioprine (AZA).
Methods:   A total of 50 kidney allograft recipients treated with prednisone, sirolimus and MMF were randomized into two groups: converted (AZA group) and continuing (MMF group). The average duration of MMF therapy prior to conversion was 43 months in each group. Inclusion criteria included: patients with serum creatinine levels of less than 200 µmol/L; no past history of acute vascular rejection or recent acute rejection 6 months before randomization; and normal liver function tests.
Results:   Baseline demographics were similar in the two groups. During the 12 month observation period, there were no acute rejection episodes in either group. There were no significant differences in overall patient or graft survival or function. AZA-treated patients had a lower incidence of gastrointestinal complications ( P  = 0.03). Daily cost reduction in the AZA group was more than $US8.79/day per patient.
Conclusion:   In general, replacing MMF with AZA in stable renal transplant recipients is well tolerated and was cost effective with no increased risk of rejection. As the this study was on relatively small samples, larger and longer follow-up studies will be needed to confirm these expected advantages for the long-term outcome and to assess the long-term safety of this minimization of immunosuppressive therapy.     

Withdrawal of steroids from triple-drug therapy in kidney transplant patients.

BACKGROUND: In renal transplant patients with stable graft function, triple-drug immunosuppression may not be necessary, while withdrawal of steroids may eliminate side effects. The primary aim of this study was to assess the risk of rejection after steroid withdrawal. METHODS: A total of 88 patients with stable graft function and serum creatinine <160 micromol/l, treated with cyclosporin A, azathioprine and prednisone were randomized into group A (n=46) with a gradual prednisone reduction to zero in the course of 6 months, and group B (n=42) on triple-drug therapy without change. At the time of randomization, fine-needle aspiration biopsy (FNAB) was carried out in all of the patients. After stopping steroids, the patients were followed up for a period of 12 months. RESULTS: Four patients failed to complete steroid withdrawal, three due to rejection, and one due to leukopenia. The proportion of rejection in three patients in group A (6.6%) was not significantly different from rejection in two patients in group B (4.8%). The mean value of serum creatinine was not significantly different in both groups in the course of follow-up. A finding of some degree of immunological activity in FNAB was made in four patients in each group, but none of these patients developed rejection. Compared with group B, significant decreases in serum cholesterol and blood leukocytes were observed in group A. Prednisone withdrawal did not have any influence on hypertension and serum triglycerides. CONCLUSIONS: Gradual withdrawal of steroids is not associated with a higher risk for rejection and has a beneficial effect on serum total cholesterol levels. FNAB was not a useful tool for predicting rejection.     

Renal allograft immunosuppression III. Triple therapy versus three different combinations of double drug treatment: two year results in kidney transplant patients

A prospective randomized trial was carried out to compare the long-term effects of triple therapy based on low-dose cyclosporin A (CyA), low-dose methylprednisolone (MP) and azathioprine (Aza) with three different double drug immunosuppressive regimens. After initial triple drug immunosuppression for 10 weeks, 128 patients were randomized into four different immunosuppressive groups: one group continued with triple therapy (group A) and the three other groups were treated with different combinations of two drugs: Aza and CyA (group B), Aza and MP (group C) and CyA and MP (group D). This report presents the 2-year results. For groups A, B, C and D, graft survivals were 75%, 78%, 84% and 81%, respectively, and patient survivals were 84%, 84%, 84% and 94%, respectively. After 2 years no patient had returned to dialysis in group C compared with one to three patients in every CyA-using group. However, at the end of the 2nd year, group C included more patients with deteriorating graft function than the other groups. Median serum creatinine was 107, 120, 139 and 129 mol/l for groups A, B, C and D, respectively. For the patients who remained on the original randomized protocol, there were no significant differences in graft function tests between the four groups, the median creatinine being 115, 115, 118 and 113 mol/l for groups A, B, C and D, respectively. Thus, no graft deterioration had occurred during the 2 years for these patients following the original protocol. Our results suggest that after initial triple therapy, patients with a first cadaveric kidney allograft can either continue with triple therapy or be converted to any of the double drug regimens without detriment to graft function, graft survival or patient survival for the next 2 years. This will allow more flexible and individual immunosuppressive treatment.     

Influenza virus vaccination in kidney transplant recipients: serum antibody response to different immunosuppressive drugs

Salles MJC, Sens YAS, Boas LSV, Machado CM. Influenza virus vaccination in kidney transplant recipients: serum antibody response to different immunosuppressive drugs.
Clin Transplant 2010: 24: E17–E23. © 2009 John Wiley & Sons A/S.   Abstract: 
Introduction:  This study prospectively accessed the immune response to the inactivated influenza vaccine in renal transplant recipients receiving either azathioprine or mycophenolate mofetil (MMF). Side effects were investigated.
Methods:  Sixty-nine patients received one dose of inactivated trivalent influenza vaccine. Antihemagglutinin (HI) antibody response against each strain was measured before and one to six months after vaccination.
Results:  Geometric mean HI antibody titers for H1N1 and H3N2 strains increased from 2.57 and 2.44 to 13.45 (p = 0.001) and 7.20 (p < 0.001), respectively. Pre- and post-vaccination protection rates for H1N1 and H3N2 increased from 8.7% to 49.3% (p < 0.001); and 36.3% (p < 0.001) and seroconversion rates were 36% and 25.3%, respectively. There was no response to influenza B. The use of MMF reduced the H1N1 and H3N2 protection rates and the seroconversion rate for the H1N1 strain when compared with the use of azathioprine, and subjects transplanted less than 87 months also had inferior antibody response. Adverse events were mild and there were no change on renal function post-vaccination.
Conclusion:  Renal transplant patients vaccinated against influenza responded with antibody production for influenza A virus strains, but not for influenza B. Use of MMF and shorter time from transplantation decreased the immune response to the vaccine.     

Enteric-coated mycophenolate sodium immunosuppression in renal transplant patients: efficacy and dosing

Mycophenolate mofetil (MMF), a mycophenolic acid (MPA) formulation, has improved both short- and long-term outcomes following renal transplantation, but is often associated with gastrointestinal (GI) complications that can lead to dose reduction or discontinuation, potentially jeopardizing patient outcomes. Enteric-coated mycophenolate sodium (EC-MPS) delivers equivalent MPA exposure to MMF and offers the potential to reduce GI burden (while maintaining patient safety). Here we review the efficacy of EC-MPS compared with MMF in renal transplant patients in terms of biopsy-proven acute rejection and graft loss, and examine the use of EC-MPS in newer regimens such as intensified dosing and calcineurin inhibitor minimization.     

Comparison of transplanted kidney function in patients on two different doses of mycophenolate mofetil

INTRODUCTION: Mycophenolate mofetil (MMF), an immunosuppressant that is widely used in renal transplant recipients, is associated with several dose-dependent hematologic and gastrointestinal side effects that lead to drug dose reduction or even discontinuation. The aim of this study was to compare the renal function and acute rejection rates of kidney allograft recipients who were on two different mycophenolate mofetil doses. METHODS: In a prospective study, 59 allograft kidney recipients who were on MMF 2 g/d were randomly selected and followed for evidences of acute rejection or drug side effects. Four patients were excluded from the study due to noncompliance, graft loss, and patient loss from opportunistic infection. Of the remaining 55 patients, 22 patients (40%) underwent MMF dose reduction to 1.35 +/- 0.23 g/d due to perceived side effects or economic reasons (group 1). The mean time for this change was 4.2 +/- 2.1 months after the kidney transplantation. The remaining patients (group 2, n = 33, 60%) had no change in MMF 2 g/d drug dosage. All patients were followed for at least 30 months after transplantation. Renal function tests (blood urea and serum creatinine) were measured monthly. Statistical analysis was performed using SPSS 11.0 (Student t test). A P value < .05 was considered significant. RESULTS: The two groups were comparable regarding age, gender, other immunosuppressive medications, and the time after transplantation. There were no episodes of acute rejection in group 1 after MMF dose reduction. The renal function (blood urea or serum creatinine levels) was comparable between the two groups at the end of study (P = .846 and .610, respectively). CONCLUSION: MMF dose reduction was not associated with an increased risk of acute renal allograft rejection or impaired graft function.     

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.     

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.     

Calcineurin inhibitor reduction based on maintenance immunosuppression with mycophenolate mofetil in renal transplant patients: POP study

Since calcineurin inhibitors (CNI) have been introduced, they have become the cornerstone of immunosuppression for renal transplant patients, but their cardiovascular and neurological toxicities, and primarily their renal toxicity, have brought about an increased effort to find combinations of immunosuppressants that are either CNI-free or that use minimum doses of these drugs. The weight of immunosuppression therefore lies with drugs that have a better toxicity profile. The POP observational transverse study including 213 renal transplant patients was designed to study CNI minimization strategies. The mean time of transplant evolution to the time of reduction was 9.9 +/- 11.8 months. The acute rejection rate to the start of reduction was 9.4%. Almost all the patients were undergoing treatment with CNI + mycophenolate mofetil (MMF) + steroids in the immediate posttransplantation period. When reduction was chosen, all patients were undergoing treatment with MMF (mean dose at the start of reduction = 1490.7 +/- 478.0 mg/d). Among the cohort, 66.7% of patients were being treated with tacrolimus (mean C0 levels 13.3 +/- 6.6 ng/mL) and 33.3% with cyclosporine (mean C0 levels 192.2 +/- 94.0 ng/mL; mean C2 levels 1097.5 +/- 457.6). The main reasons for withdrawal were nephrotoxicity (55.9% of the cases), as well as prevention of adverse effects (21.6%). The mean target CNI dose reduction was 41.4% +/- 21.45% in the tacrolimus group and 28.6 +/- 10.0% in the cyclosporine group. In conclusion, CNI toxicity, primarily renal toxicity, makes reduction of these drugs based on the use of full MMF doses an alternative to manage renal transplant patients.     

Sirolimus monotherapy as maintenance immunosuppression: single-center experience in 50 kidney transplant patients

INTRODUCTION: Chronic allograft nephropathy, cardiovascular mortality, and posttransplant malignancy are complications of conventional immunosuppression after kidney transplantation. We reported the feasibility of maintenance monotherapy with sirolimus (SRL) in a pilot experience. The aim was to study safety and feasibility of SRL maintenance monotherapy in 50 kidney transplant patients. METHODS: All patients from our center with at least 6 months follow-up on SRL monotherapy were included. During the first month after start of SRL monotherapy, follow-up visits were performed weekly, then each month for the following 2 months. Each follow-up visit included a physical exam and laboratory screening. RESULTS: Mean follow-up on SRL monotherapy was 34.7 +/- 14.9 months. The time between transplantation until start of monotherapy was 7.7 +/- 3.3 years. No rejections occurred. During follow-up, two patients died of cardiovascular disease (already diagnosed before monotherapy); one, of previously diagnosed posttransplant malignancy and one, of hepatitis C-related liver failure. Glomerular filtration rate (GFR) was 53 mL/min x 1.73 m2 at start of monotherapy and 50 mL/min x 1.73 m2 after 4 years. Proteinuria was 632 +/- 562 mg/24 hours at 4 years. During the follow-up, no significant changes in the lipid profile, glycemia, or hemoglobin occurred. CONCLUSIONS: Sirolimus monotherapy is safe in a selected group of immunological low-risk patients without increasing the risk of rejection.     

Tacrolimus (FK506) versus cyclosporine microemulsion (neoral) as maintenance immunosuppression therapy in kidney transplant recipients

The effects of the calcineurin inhibitors tacrolimus (FK506) and cyclosporine (Neoral) on graft survival, function, and metabolic profile were evaluated in 69 patients receiving Neoral (group 1) and 54 patients receiving FK506 (group 2) for maintenance immunosuppression following kidney transplantation. Recipient and donor demographics and induction therapy were comparable, except for a higher number of sensitized patients in group 2 (n = 13). Acute rejection timing, severity, and infection rates and types were similar in both groups. During hospitalization, at 6 months, and at 1 year following transplantation, no significant differences were noted between groups in fasting glucose, serum cholesterol levels, triglyceride levels, or need for insulin or antihypertensive therapy. Mean serum creatinine levels on discharge (1.42 mg/dL +/- 0.14 vs 1.68 mg/dL +/- 0.3), at 1 month (1.45 mg/dL +/- 0.1 vs 1.39 mg/dL +/- 0.11), 3 months (1.46 mg/dL +/- 0.09 vs 1.32 mg/dL +/- 0.14), and 1 year (1.29 mg/dL +/- 0.08 vs 1.19 mg/dL +/- 0.09), but not at 6 months (1.42 +/- 0.37 vs 1.10 +/- 0.07; P = .001), were comparable between groups. The 1-year patient and graft survival rates were 98.3% for group 1 and 94.5% for group 2. When evaluated for acute rejection, infection, and metabolic differences, we conclude that both tacrolimus and cyclosporine are effective and safe calcineurin inhibitors for short-term use in kidney transplantation. A similar study is proposed to evaluate the long-term effects of both agents.     

Long-term renal transplant function in recipient of simultaneous kidney and pancreas transplant maintained with two prednisone-free maintenance immunosuppressive combinations: tacrolimus/mycophenolate mofetil versus tacrolimus/sirolimus

BACKGROUND: It is not known how different steroid-free immunosuppressive combinations affect long-term kidney transplant function in recipients of simultaneous kidney and pancreas transplant (SPK). Here, we sought to evaluate, in SPK recipients, the impact on long-term renal allograft function of two Tac-based prednisone-free maintenance immunosuppressive protocols: tacrolimus (Tac)/mycophonelate mofetil (MMF) versus Tac/ sirolimus (SRL). METHODS: In this single-center, retrospective, sequential study, we analyzed 59 SPK transplant patients with at median follow up of 5 years. All patients received induction therapy with thymoglobulin and maintenance immunosuppression with Tac/MMF (n=22) or Tac/SRL (n=37). There were no differences between the two groups in regards to age, gender, race, panel reactive antibodies, degree of mismatch, donor age, incidence of delay graft function, and Tac trough levels at different time points after transplantation. RESULTS: Kaplan-Meier patient survival at 6 years after transplantation was not statistically different between the two groups. Rate of ACR was similar. Kidney survival, even if not statistically significant, was better in the Tac/MMF group than in the Tac/SRL (90.7% vs. 70.7%, P=0.09). The slope of glomerular filtration rate decline per month at 5 years after transplantation was not statistically different between the two groups. Both groups had the same decline over time in glomerular filtration rate of 0.40+/-0.06 mL/min/1.73/month. Pancreas survival at 6 years after transplantation was 100% in both treatment groups. CONCLUSIONS: Our data suggest that, in SPK recipients, long-term kidney allograft survival and function are not statistically different. A trend toward an increased rate of renal allograft loss was found in the Tac/SRL-treated group.     

Infectious complications in geriatric renal transplant patients: comparison of two immunosuppressive protocols

BACKGROUND: It has been well documented that a regimen of mycophenolate mofetil (MMF), cyclosporine (CsA), and prednisone (Pred) reduces the incidence of acute rejection in renal transplant recipients, as compared with previous regimens based on azathioprine (AZA), CsA, and Pred. In the general renal transplant patient population, immunosuppressive regimens that include MMF are usually well tolerated. It is not clear whether this holds true for older transplant recipients, who may be more susceptible to complications from the greater immunosuppression conferred by MMF. METHODS: We retrospectively analyzed our geriatric renal transplant population (age >60 years, 1990-1998) and compared a cohort of 46 patients treated with AZA, Pred, and CsA to a cohort of 45 patients treated with MMF, Pred, and CsA. RESULTS: There were no significant differences between the groups with regard to pretransplantation demographics. Patient and graft survival during the first year was not significantly different between the groups. During the first year of follow-up, we observed 27 infections requiring hospitalization in 15 patients in the MMF-treated group as compared with 10 infections in 7 patients in the AZA-treated group. A Cox proportional hazard model accounting for the above mentioned covariates isolated MMF versus AZA as a significant risk factor for the occurrence of serious infectious events (all: P<0.01; cytomegalovirus, fungal: P<0.01). CONCLUSION: We conclude that an immunosuppressive regimen of MMF, CsA, and Pred seems to be correlated with an increased incidence of infectious adverse events as compared with AZA, CsA, and Pred in elderly patients.     

免疫抑制剂对肾移植受者外周血单个核细胞Foxp3 mRNA表达的影响

目的 探讨免疫抑制剂对肾移植受者外周血单个核细胞中叉状头螺旋转录因子Foxp3 mRNA表达的影响.方法 采用实时荧光定量PCR法检测钙调磷酸蛋白酶抑制剂(CNI)组、雷帕霉素组、终末期肾病组以及正常对照组新鲜外周血单个核细胞中Foxp3 mRNA的表达水平,苦味酸法检测同期血肌酐浓度,比较各组间Foxp3 mRNA表达水平和肌酐浓度的差异.结果 CNI组(0.1089±0.0967)的外周血Foxp3 mRNA表达水平低于雷帕霉素组(1.1264±0.6565)、正常对照组(0.9380±0.3614)和终末期肾病组(1.1200±0.5703),差异均有统计学意义(均P<0.01).雷帕霉素组[(173.58±44.65) μmol/L]与CNI组[(150.45±46.21)μmol/L]血肌酐浓度差异无统计学意义(P>0.05).结论 CNI类免疫抑制剂抑制了肾移植后免疫耐受的诱导,而雷帕霉素可能参与了免疫耐受的诱导和维持.     

Thymoglobulin versus ATGAM induction therapy in pediatric kidney transplant recipients: a single-center report

BACKGROUND: Induction immunosuppressive therapy with the anti-T-cell antibody Thymoglobulin decreases the incidence of acute rejection in adult kidney transplant (KTx) recipients, but limited data are available for pediatric KTx recipients. METHODS: We conducted a historical cohort study to compare rates of survival, rejection, and infection in pediatric (age <19 years) KTx recipients who received induction therapy with polyclonal antibody, ATGAM (n=127) or Thymoglobulin (n=71), from December 1, 1992, to January 31, 2003. Maintenance immunosuppression included cyclosporine, azathioprine or mycophenolate mofetil, and prednisone. Mean follow-up was 90+/-25 months for ATGAM recipients and 32+/-15 months for Thymoglobulin recipients. RESULTS: Overall, the incidence of acute rejection was lower in Thymoglobulin recipients versus ATGAM recipients (33% vs. 50%, P=0.02). Epstein-Barr virus (EBV) infection was higher in Thymoglobulin recipients versus ATGAM recipients (8% vs. 3%, P=0.002). But the two groups did not significantly differ in patient and graft survival rates, incidence of chronic rejection, EBV lymphoma, or other infection. CONCLUSIONS: Thus, Thymoglobulin induction was associated with a decreased incidence of acute rejection and an increased incidence of EBV infection in pediatric KTx recipients. EBV monitoring should be performed in EBV-naive recipients receiving Thymoglobulin.