Prospective, Pilot, Open-Label, Short-Term Study of Conversion to Leflunomide Reverses Chronic Renal Allograft Dysfunction

Leflunomide (LEF) is a synthetic isoxazole derivative with anti-inflammatory and antiviral properties, which has been reported to prevent acute rejection and delay progression of chronic allograft nephropathy (CAN) in animal models. We performed a pilot, crossover trial in 22 renal transplant recipients who were converted from azathioprine (AZA) or mycophenolate mofetil (MMF) to LEF in an effort to slow progression of renal dysfunction [deteriorating renal function (n = 5), cyclosporine (CyA) nephrotoxicity (n = 4) or biopsy-proven CAN (n = 13)]. Baseline maintenance immunosuppression consisted of CyA, AZA or MMF and prednisone. Six-month postconversion patient and graft survival was 100% and 91%, respectively. Mean serum creatinine 6months preconversion was 2.2 +/- 0.6mg/dL, at initiation was 3.0 +/- 1.1 mg/dL, and 6 months postconversion was 2.8 +/- 1.3 mg/dL. The rate of change in serum creatinine was 35 +/- 39%/6 months preconversion and -5 +/- 21%/6 months postconversion to LEF (p = 0.003). Two patients discontinued LEF for diarrhea and myalgia. No readmissions, increase in liver function tests, infections or acute rejection episodes occurred. Mean CyA levels did not change, 146 +/- 72 ng/ mL pre-LEF vs. 132 +/- 51 ng/mL post-LEF, p = NS. Conversion to LEF reversed progression of chronic renal allograft dysfunction with minimal toxicity.     

Cyclosporin withdrawal with concomitant conversion from azathioprine to mycophenolate mofetil in renal transplant recipients with chronic allograft nephropathy: a 2-year follow-up

Because recent large studies have demonstrated that mycophenolate mofetil (MMF) is superior to azathioprine (AZA) as a post-transplant immunosuppressant, it has been speculated that MMF could have a cyclosporin (CsA)-sparing effect in renal transplant recipients with chronic allograft dysfunction. Between April 1996 and October 1998, 31 patients with chronic allograft dysfunction were assigned to have conversion from AZA to MMF with concomitant CsA withdrawal. Patient and graft outcomes were analysed. Mean follow-up time after MMF conversion was 27+/-11 months. Serum creatinine concentration (sCt) significantly decreased after conversion and remained stable at the end of follow-up (227+/-31 micro mol/l vs. 185+/-50 micro mol/l; P<0.0005). Mean variation in sCt was -24% after conversion, whereas it was +20% in the year before conversion ( P<0.001). There was a significant inverse relationship between proteinuria at baseline and improvement in renal function (r=-0.35; P=0.01). Proteinuria increased during follow-up (0.79+/-0.6 vs. 1.79+/-1.08 g/day; P=0.04). Isolated CsA nephropathy was associated with the best outcome. Renal function significantly improved in patients with grade 1 chronic rejection and remained stable in patients with grade 2 chronic rejection. Two patients (6.5%) experienced late acute rejection, respectively 13 and 24 months after CsA withdrawal. Eight patients (29%) experienced systemic infections requiring hospitalization. Blood pressure control and lipid profile improved after conversion. CsA withdrawal with a concomitant switch from AZA to MMF allows a substantial and durable improvement in renal function. Both allograft histology and proteinuria at baseline are predictive of the evolution of renal function after conversion. Physicians should consider the risk of over-immunosuppression possibly associated with this therapeutic strategy.     

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.     

Reversal of chronic cyclosporine nephrotoxicity after heart transplantation-potential role of mycophenolate mofetil.

BACKGROUND: Chronic cyclosporine nephrotoxicity (CCN) after heart transplantation is a progressive condition that may lead to end-stage renal failure. The extent to which CCN is reversible with reduction or withdrawal of cyclosporine therapy is unknown. The aim of this study was to assess the reversibility of CCN and to assess the safety and efficacy of a strategy of cyclosporine dosage reduction, combined with conversion from azathioprine to mycophenolate mofetil (AZA/MMF switch) to maintain immunosuppression. METHODS: An AZA/MMF switch followed by cyclosporine dose reduction was undertaken in 30 heart transplant recipients (23 men, 7 women; mean age, 54 +/- 2 years) with established CCN at a mean of 90 +/- 9 months after transplantation (range, 17-182 months). The mean maintenance MMF dosage was 2.3 +/- 0.1 g/day (n = 28). Mean cyclosporine dosage was decreased from 2.3 +/- 0.2 mg/kg/day before AZA/MMF switch to 1.6 +/- 0.2 mg/kg/day. RESULTS: Three patients (10%) were withdrawn from MMF, 2 because of diarrhea and the third because of severe pneumonia that developed within 2 weeks of AZA/MMF switch. All 3 were restabilized with AZA. One patient (4%) experienced acute rejection 7 months after AZA/MMF switch. This resolved after an oral pulse of prednisolone. Systemic infections occurred in 6 patients within 12 months of AZA/MMF switch. Actuarial survival 1 year after AZA/MMF switch was 86% +/- 6%. One patient died of infection and 3 of other causes. Serum creatinine concentration decreased from 248 +/- 15 micromol/liter before cyclosporine dosage reduction to 193 +/- 11 micromol/liter and 206 +/- 19 micromol/liter at 3 and 12 months after dosage reduction (both p < 0.01 versus baseline, n = 23). Of the 23 patients who remained on MMF at 12 months, a decrease in serum creatinine was documented in 19 (83%). Four patients showed no improvement or showed deterioration in renal function, and three of these progressed to end-stage renal failure. CONCLUSIONS: Chronic cyclosporine nephrotoxicity has a significant reversible component in most patients. A strategy of AZA/MMF switch combined with cyclosporine dosage reduction is generally well tolerated and results in short-term improvement in renal function in most patients. Close vigilance is required during the first 12 months after AZA/MMF switch because both acute rejection and infection may occur.     

Mycophenolate mofetil may allow cyclosporine and steroid sparing in de novo heart transplant patients

BACKGROUND: Mycophenolate mofetil (MMF) provides superior prophylaxis against acute rejection when compared with azathioprine (AZA) in heart and renal transplantation. However, it remains unclear whether this results in improved survival or reduced morbidity after heart transplantation. METHOD: In a sequential study, 240 cardiac transplant patients were treated with either MMF (n=119) or AZA (n=121) both in combination with cyclosporine and corticosteroids after rabbit antithymocyte globulin induction. RESULTS: By protocol lower cyclosporine levels were targeted in the MMF group during the first year (e.g. 203+/-52 ng/mL MMF vs. 236+/-59 ng/mL AZA, P=0.0006 at 6 months). Patient survival at 1 year (82% MMF vs. 79% AZA, P=0.55) and at 3 years was similar in both groups. The cumulative probability of receiving antirejection treatment within 1 year was lower in the MMF group, as was biopsy-proven acute rejection with International Society of Heart and Lung Transplantation grade > or =3A (24% vs. 35%, P=0.03). The MMF group also had fewer episodes requiring cytolytic therapy (6% vs. 13%, P=0.04) and more patients had steroids withdrawn by 1 year (66% vs. 32%, P<0.001). Renal function was better in the MMF group with lower creatinine levels at 1 year (133+/-45 vs. 155+/-46 micromol/L, P=0.0004). Calculated creatinine clearance (Cockcroft and Gault formula) at 1 year was also better (MMF 74+/-32 mL/min vs. AZA 62+/-24 mL/min, P=0.004). CONCLUSION: Our results suggest that immunosuppression with MMF rather than AZA may allow lower cyclosporine levels, better renal function, and increased steroid weaning at 1 year while also achieving better control of acute rejection.     

Mycophenolate mofetil versus azathioprine therapy is associated with a significant protection against long-term renal allograft function deterioration

BACKGROUND: To evaluate the association of long-term continuous mycophenolate mofetil (MMF) versus azathioprine (AZA) therapy and renal allograft function, as measured by the slope of reciprocal creatinine, we analyzed 49,666 primary renal allograft recipients reported to the United States Renal Data System between October 31, 1988 and June 30, 1998. METHODS: The primary study endpoint was defined as a greater than 20% decrease below a 6-month baseline of 1/serum creatinine (SCr) (slope of reciprocal creatinine) at or beyond 1 year after transplantation. A secondary endpoint was defined as reaching an SCr value greater than 1.6 mg/dL. Univariate Kaplan-Meier analysis and multivariate Cox proportional hazard models were used to investigate the risk of reaching the study endpoints. Multivariate analyses were corrected for potential confounding covariates. RESULTS: According to the Cox proportional hazard model, 12-month continued therapy of MMF versus AZA was associated with a protective effect against declining renal function, as measured by the slope of reciprocal creatinine (relative risk [RR]=0.84, confidence interval 0.78-0.91, P<0.001). For 24-month continued therapy of MMF versus AZA, MMF was associated with a further decreased risk for a decline in renal function (RR=0.66, confidence interval=0.57-0.77, P<0.001). Furthermore, MMF was associated with a protective effect against reaching the SCr threshold of 1.6 mg/dL (RR=0.80, P<0.001) beyond 12 months posttransplantation. CONCLUSIONS: Continuous use of MMF versus AZA was associated with a protective effect against declining renal function beyond 1 year after transplantation. Further study is needed to confirm that continued MMF therapy is protective against long-term deterioration in renal function.     

Mycophenolate mofetil and sirolimus as calcineurin inhibitor-free immunosuppression for late cardiac-transplant recipients with chronic renal failure

BACKGROUND: Calcineurin-inhibitor (CNI)-related renal failure is a common problem after cardiac transplantation (HTx). The aim of this study was to introduce a CNI-free immunosuppressive regimen to HTx recipients with late posttransplant renal impairment and to evaluate the impact of conversion to this new immunosuppression (mycophenolate mofetil [MMF] and sirolimus [Sir]) treatment on renal function. METHODS AND RESULTS: Thirty-one HTx patients (25 men, 6 women; 0.2-14.2 years after transplantation) with CNI-based immunosuppression and a serum creatinine greater than 1.9 mg/dL were included in the study. Creatinine and cystatin levels were monitored to detect renal function. Mean patient age was 50+/-14 (range 19-74) years. Conversion was started with 6 mg Sir, continued with 2 mg, and the dose was adjusted to achieve target trough levels between 8 and 14 ng/mL. MMF was continued with trough level adjusted (1.5-4 microg/mL). Subsequently, the CNIs were tapered down and stopped. Clinical follow-up (first and every 3 months after conversion) included endomyocardial biopsies, echocardiography, and laboratory studies. Survival was 90% after a mean follow-up of 13+/-95 months. No acute rejection episode was detected during the study period. Renal function improved significantly after conversion: creatinine preconversion vs. postconversion: 3.14+/-0.76 mg/dL vs. 2.14+/-0.83 mg/dL, P =0.001. Cystatin preconversion vs. postconversion: 2.95+/-1.06 mg/L vs. 2.02+/-1.1 mg/L, P =0.01. In three patients, hemodialysis therapy was stopped completely after conversion. Graft function remained stable. Fractional shortening preconversion vs. postconversion: 36.9+/-6% vs. 36.4+/-6%. There were no serious adverse events. One patient had to be excluded because of noncompliance. CONCLUSIONS: Conversion from CNI-based immunosuppression to MMF and Sir in HTx patients with chronic renal failure was safe, preserved graft function, and improved renal function.     

Randomized, prospective trial of mycophenolate mofetil versus azathioprine for prevention of acute renal allograft rejection after simultaneous kidney-pancreas transplantation

BACKGROUND: In simultaneous kidney-pancreas (SPK) transplantation, manifestations of renal allograft rejection typically become evident before those of pancreatic rejection. This study compared mycophenolate mofetil (MMF) and azathioprine (AZA) in prevention of renal rejection after primary SPK transplantation. METHODS: In an open-label, randomized, multicenter study, patients received MMF 1.5 g twice daily (n=74) or AZA 1-3 mg/kg daily (n=76) for 1 year after transplantation. The incidence of rejection was assessed at 6 months. Adverse events were tracked through 1 year. Survival data are reported through 2 years. RESULTS: At 6 months, efficacy results for MMF vs. AZA patients, respectively, were the following: rejection (27% vs. 39%); rejection or death (34% vs. 42%); rejection, graft loss, death, or premature withdrawal (i.e., treatment failure; 41% vs. 55%). Six-month efficacy trends favored MMF, and time to rejection or treatment failure was significantly longer when compared with AZA (P=0.049). One-year efficacy results for MMF vs. AZA patients, respectively, were the following: treatment of renal rejection (35% vs. 47%); renal allograft loss or death (9% vs. 12%); pancreas allograft loss or death (15% vs. 14%). Five MMF patients (7%) and four (5%) in the AZA group died. More MMF than AZA patients developed opportunistic infections (54% vs. 38%), but the pathogens did not differ. CONCLUSIONS: Trends for most efficacy parameters favored MMF over AZA, and time to renal allograft rejection or treatment failure was statistically significantly longer for MMF. The use of MMF in the treatment of SPK recipients is a useful advance.     

Formation of donor-specific human leukocyte antigen antibodies after kidney transplantation: correlation with acute rejection and tapering of immunosuppression

BACKGROUND: Before kidney transplantation, a serological crossmatch is routinely performed between donor and recipient to prevent hyperacute rejection by donor-specific anti-human leukocyte antigen (HLA) antibodies. After transplantation, the presence of these antibodies is not routinely monitored. We wanted to know whether donor-specific anti-HLA antibodies are detectable during acute rejection (AR), before or after reduction of immunosuppression in kidney transplant recipients who were converted from cyclosporine A (CsA) to the less nephrotoxic azathioprine (AZA) or mycophenolate mofetil (MMF) at 1 year after transplantation. METHODS: Plasma samples were collected before transplantation, at several time points after transplantation, and during AR. Antibodies were measured in 29 patients: 5 patients with AR during the first year after transplantation (before conversion), 14 patients with AR after conversion or dose-reduction of AZA or MMF, and a control group of 10 patients without AR during a follow-up of 2 years (1 year before and 1 year after conversion of immunosuppression). Antibodies were measured by complement-dependent cytotoxicity assay, enzyme-linked immunosorbent assay (ELISA), and flow-cytometry in a crossmatch with donor spleen cells. RESULTS: Donor-specific antibodies were not detectable after transplantation in the control group without AR, nor in patients with AR shortly after transplantation during CsA therapy. After conversion from CsA to AZA or MMF, antibodies appeared only in one patient after graft failure followed by transplantectomy and in patients during AR on AZA but not on MMF therapy. CONCLUSION: In this patient group, we could not detect donor-specific antibodies during CsA treatment, not even at the time of AR using three different techniques. Donor-specific antibodies were primarily present during AR in patients converted from CsA to AZA and were not found in the sera from patients converted to MMF.     

Reduced kidney transplant rejection rate and pharmacoeconomic advantage of mycophenolate mofetil.

BACKGROUND: Several multinational controlled clinical trials have shown that triple therapy immunosuppressive regimens which include mycophenolate mofetil (MMF), cyclosporin A (CSA) and steroids (S) are superior compared with conventional regimens which include azathioprine (AZA), CSA and S, mainly because MMF reduces the rate of acute rejection episodes in the first 6 months after kidney transplantation. Post-marketing studies are useful to evaluate the general applicability and costs of MMF-based immunosuppressive regimens. METHODS: Based on the excellent results of the published controlled clinical trials, we have changed the standard triple therapy immunosuppressive protocol (AZA+CSA+S) to an MMF-based regimen (MMF+CSA+S) at our centre. To analyse the impact of this change in regimen, we have monitored 6-month patient and graft survival, rejection rate, serum creatinine and CSA levels, as well as the costs of the immunosuppressive and anti-rejection treatments, in 40 consecutive renal transplant recipients (MMF group) and have compared the data with 40 consecutive patients transplanted immediately prior to the change in regimen (AZA group). RESULTS: Recipient and donor characteristics were similar in the AZA and MMF groups. Patient survival (37/40; 92.5% in the AZA group vs 38/40; 95% in the MMF group), graft survival (36/40 vs 36/40; both 90%) and serum creatinine (137+/-56 vs 139+/-44 micromol/l) after 6 months were not significantly different. However, the rate of acute rejection episodes (defined as a rise in creatinine without other obvious cause and treated at least with pulse steroids) was significantly reduced with MMF from 60 to 20% (P=0.0005). The resulting cost for rejection treatment was lowered 8-fold (from sFr. 2113 to 259 averaged per patient) and the number of transplant biopsies was lowered > 3-fold in the MMF group. The cost for the immunosuppressive therapy was increased 1.5-fold with MMF (from sFr. 5906 to 9231 per patient for the first 6 months). CONCLUSIONS: The change from AZA to MMF resulted in a significant reduction in early rejection episodes, resulting in fewer diagnostic procedures and rehospitalizations. The optimal long-term regimen in terms of patient and pharmacoeconomic benefits remains to be defined.     

Mycophenolate mofetil (MMF) in the treatment of chronic renal rejection

BACKGROUND: Experimental studies suggest the efficacy of MMF in the treatment of chronic renal rejection in rats. Studies on the efficacy of MMF in chronic renal rejection in man are scarce and controversial. AIM: The aim of this study was to verify in a prospective non-randomized study the efficacy of MMF given at the dose of 2 g/day in substitution of azathioprine (AZA) in the chronic rejection of cadaveric kidney transplantation. PATIENTS AND METHODS: Twelve patients with histologically proven chronic renal rejection were enrolled. The patients were 5 males and 7 females. Mean age 38.3 +/- 13.8 years, with a mean duration of transplant of 39 +/- 19 months. Mean serum creatinine values at -6, -3, 0, +3, +6, +12 months were respectively 1.72 +/- 0.33, 1.84 +/- 0.36, 2.15 +/- 0.50, 1.88 +/- 0.54, 1.81 +/- 0.71, 1.73 +/- 0.58 mg/dl. Mean creatinine clearance values were 58.85 +/- 10.06,48.8 +/- 13.3,45.8 +/- 10.2, 54.7 +/- 13.3, 51 +/- 12.7, 57.7 +/- 18.5 ml/min. Mean deltaGFR before MMF was -2.15 ml/month. RESULTS: After MMF introduction, the overall GFR decrease attenuated. In particular in seven patients after MMF administration, we obtained a significant reduction of mean serum creatinine value (1.84 +/- 0.55 vs. 1.38 +/- 0.41mg/dl; p = 0.004). In three patients, we obtained a stabilization in GFR. Two patients were slowly progressing even after MMF introduction. After a switch to MMF in almost all patients, we obtained an improvement of renal function. In three patients, we obtained a stabilization of renal function without regression. In particular, seven patients showed a remarkable improvement of renal function. CONCLUSIONS: In conclusion our data even if concerning a small number of patients, confirm the efficacy of MMF in the treatment of renal allograft chronic dysfunction.     

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.     

Comparison of long-term actual renal allograft survival in mycophenolate mofetil and azathioprine-based triple drug immunosuppression protocols

INTRODUCTION: The use of mycophenolate mofetil (MMF) in renal transplantation results in a 50% lower incidence of acute rejection compared to azathioprine (AZA). However, the graft survival reports are conflicting: the European trial and US database analysis suggest better survival with MMF, an observation that was not seen in the US and tricontinental studies. METHODS: We retrospectively reviewed our single-center experience (60% African-Americans) comparing the serum creatinine (SCr) values and 3-year actual graft survival with MMF versus AZA-based immunosuppression. Group I included patients transplanted between January 1990 and December 1992 on cyclosporine (CSA), AZA, and steroids; group II subjects, from January 1996 to December 1998 on CSA, MMF, and steroids. We analyzed SCr and all causes of graft losses at 3, 6, 12, 18, 24, and 36 months posttransplantation. RESULTS: The patient demographics were similar in both groups as was the mean SCr values at different times. The time-group interaction for SCr, the Kruskal-Wallis test for SCr for different categories (<1.5, 1.5 to 2.0, 2.0 to 2.5, and >2.5 mg/dL) and the all-cause graft loss between the two groups were not significantly different. CONCLUSION: Our results failed to show better long-term actual graft survival despite the 6-year interval between the two groups. These findings agree with the results of the United States and the tricontinental studies. A lower incidence of acute rejection early after transplantation observed with MMF may not always translate into a long-term benefit, possibly due to the influence of nonimmunological factors, such as hypertension, calcineurin inhibitor toxicity, more frequent cytomegalovirus infections, and increased attempts to withdraw steroids using MMF-based protocols.     

Renal allograft biopsy and conversion of cyclosporine to azathioprine

A prospective nonrandomized study was conducted to evaluate the results of two conversion protocols on two similar groups of renal graft recipients totaling 54 patients who were converted from CsA to AZA at 6-12 months posttransplant. With protocol I, 24 patients (3 haploidentical, 21 cadaveric recipients) were converted with a graft biopsy followed by a 14-day overlap of CsA and AZA before the CsA dose was tapered and discontinued in 6 days. Of the 24 patients, 8 were found to have occult rejection in biopsy and received methylprednisolone 500 mg boluses for three days before overlap started. Thirty patients (2 haploidentical, 28 cadaveric recipients) were converted with protocol II, which had CsA and AZA overlap and tapering schedules identical to those of protocol I without a preconversion biopsy. Follow-up extended as far as 3 years posttransplant. There was a substantial incidence of chronic rejection and graft loss after conversion in protocol II patients. We also found that there was a possible link between postconversion acute rejection and late graft loss from chronic rejection. The incidence of acute rejection after conversion was significantly lower among protocol I patients as compared with that of protocol II (4% vs. 37%, P less than 0.001). However, if 8 patients with occult rejection in the preconversion biopsy were added to the total number of postconversion rejection in protocol I, the incidence of postconversion rejection in this group (38%) would be similar to that of protocol II. Using the time of conversion as the onset of the risk, protocol I patients had better graft survival than protocol II (100% vs. 80%, P less than 0.005) at 3 years posttransplant. If conversion becomes necessary, we recommend a preconversion graft biopsy to identify and treat patients with occult rejection before the beginning of CsA and AZA overlap, especially for those patients whose creatinine is higher than 2 mg/dl without obvious cause before conversion.     

Conversion of azathioprine to mycophenolate mofetil and chronic graft failure progression

The purpose of the study was to evaluate the impact of conversion from azathioprine (AZA) to mycophenolate mofetil (MMF) on graft function in 35 renal transplant recipients with chronic allograft nephropathy (CAN). The immunosuppressive regimen originally consisted of AZA, cyclosporine (CsA), and prednisone (Pr). At the onset of the study (mean period = 39 posttransplant months), a graft biopsy was performed on all patients who were randomly divided into group 1 (n = 17) in whom MMF was introduced instead of AZA. The remaining 18 subjects (group 2) were maintained on the previous regimen. Two periods were analyzed: period I: 12 months before, and period II: 12 months after biopsy and therapy conversion. Graft function was assessed monthly by measurements of the 24-hour creatinine clearance (CCr). Analysis of variance (ANOVA) was used to compare the differences in CCr and proteinuria between the two groups. No difference was observed in the baseline characteristics, in the incidence of delayed graft function and acute rejection, or in the mean CsA dose. Pathohistological analysis revealed advanced CAN in the majority of patients in both groups. The morphological changes negatively correlated with graft function. The graft function showed parallel deterioration in the two groups; no significant difference was observed in the mean CCr values in the periods studied. Proteinuria was similar for both groups throughout the study. Conversion of AZA to MMF in recipients with CAN, albeit safe, was without significant benefit on the progression of chronic graft failure over the period of a year.     

Efficacy of mycophenolate mofetil versus azathioprine after renal transplantation: a systematic review

INTRODUCTION: Our objective was to evaluate the efficacy of mycophenolate acid (MMF) versus azathioprine (AZA) after renal transplantation. MATERIALS AND METHODS: The following electronic databases were searched: Medline, Embase, Cochrane library, and Chinese Biomedicine database (CBM). Randomized controlled trials (RCTs) were subjected to Revman 4.11 for statistical analyses. RESULTS: Twenty-three RCTs were identified to compare MMF and AZA for antirejection, prophylaxis after renal transplantation. The data showed that MMF (2 g/d) was more beneficial than AZA to improve graft and long-term patient survivals, but there was no statistical differences between MMF (3 g/d) and AZA. Whether at 6 months or at 1 year after renal transplantation, the use of MMF (2 g/d) or MMF (3 g/d) markedly reduced the incidence of biopsy-proven rejection. CONCLUSION: Compared with AZA, MMF is a more potent immunosuppressive drug, that is more efficient in reducing the incidence of acute rejection episodes after renal transplantation. MMF can improve the graft and patient survival rate. The 2 g per day dosage is more acceptable.     

Increased incidence of allograft rejection in stable heart transplant recipients after late conversion from mycophenolate mofetil to azathioprine.

Mycophenolate mofetil (MMF) is a safe and effective immunosuppressive agent in kidney and liver transplantation. Preliminary studies also support its use in heart transplantation. However, the cost of MMF is substantially greater than azathioprine (AZA), the current alternative. Since the majority of rejection episodes occur within the first few months of transplantation, using MMF early after transplantation and subsequently converting to AZA, after the risk of rejection has diminished, might be cost-effective. In order to evaluate the safety of such a strategy in heart transplant recipients, we reviewed the rejection profiles of a group of patients who were converted from MMF to AZA late after transplantation. Forty-three stable patients on chronic MMF therapy as part of an open-label, long-term safety study were converted to either commercially available MMF (CellCept) or AZA, at the conclusion of the study. Demographic variables, rejection histories before and after conversion, and immunosuppressive regimens were examined. Twenty-three patients were continued on commercial MMF and 20 were converted to AZA therapy. The average duration of MMF therapy prior to conversion was 41 months in each group. Baseline demographics were similar in the two groups. Treated allograft rejection occurred in 10 of 20 patients converting to AZA, as compared to only 1 of 23 patients remaining on MMF; p = 0.002. Additionally, mean scores (1-5 scale) for the three biopsies before and after conversion favored continued MMF therapy (1.5+/-0.6 before and 1.2+/-0.4 after conversion in MMF group vs. 1.3+/-0.5 before and 1.7+/-0.9 after conversion to AZA; p = 0.02). No allograft loss occurred as a result of conversion. These data suggest that conversion from MMF to AZA, even late after transplantation, can be associated with allograft rejection. The costs associated with these rejection episodes (the additional immunosuppressive agents, endomyocardial biopsies, and physician visits) may exceed the potential cost savings of converting stable heart transplant recipients from MMF to AZA.     

Randomized study on the conversion of treatment with cyclosporine to azathioprine or mycophenolate mofetil followed by dose reduction

BACKGROUND: The introduction of cyclosporine (CsA) in kidney transplantation has improved early graft survival. However, its long-term use is associated with impairment of renal function and increased cardiovascular risk factors. To avoid CsA-related long-term adverse effects, patients were converted to either azathioprine (AZA) or mycophenolate mofetil (MMF) 1 year after transplantation. METHODS: Between September 1995 and January 1997, 64 stable renal transplant recipients on CsA and prednisone treatment were included in a prospective, randomized study. Patients were randomized for conversion of CsA to 2 mg/kg AZA (n=30) or 1 g of MMF twice daily (n=34). All patients remained on low-dose steroids. To decrease the total immunosuppressive load, a dose reduction in MMF and AZA was performed at 4 and again at 8 months after conversion. Mycophenolic acid trough levels were measured at regular intervals. RESULTS: After conversion, a decrease in serum creatinine was found for both groups: for MMF, 132 to 109 micromol/L (P=0.016); and for AZA, 123 to 112 micromol/L (P<0.0001). After conversion, more acute rejections occurred in the AZA group (11/30) compared to the MMF group (4/34) (P=0.04). Dose reduction of MMF to 500 mg twice daily and of AZA to 1.0 mg/kg elicited three rejections in both groups. The incidence of side effects and infections were similar. CONCLUSION: Discontinuation of CsA spared renal function. In patients converted to MMF significantly less rejections occurred compared to patients converted to AZA. Furthermore, dose reduction of both AZA and MMF is possible in the majority (72%) of the patients.     

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.     

36-month follow-up of 75 renal allograft recipients treated with steroids, tacrolimus, and azathioprine or mycophenolate mofetil

OBJECTIVES: The aim of this retrospective study was to assess the incidence of acute rejection episodes (AR), diabetes mellitus (DM), and serum creatinine (SCr) among renal transplant recipients treated with tacrolimus (Tac), steroids (S), and mycophenolate mofetil (MMF) or azathioprine (Aza). METHODS: Seventy-five renal allograft recipients enrolled in the COSTAMP study were followed for a period of 3 years. Patients were randomized to receive either Tac and MMF (n = 41) or Tac and Aza (n = 34) concomitantly with steroids. Follow-up assessments were performed at 3, 6, 12, 24, and 36 months. RESULTS: Patient survival at month 36 was 91.18% in the Tac/Aza/S group and 97.56% in the Tac/MMF/S group. Graft survival at month 36 was 82.35% and 85.37%, respectively. During the study period, 22 cases of biopsy-proven AR were diagnosed in 17 patients (22.6%). After 36 months the total number of AR was 11 in the Aza-treated group (32.4%) and 11 in the MMF-treated group (26.8%). DM was diagnosed de novo in 17 individuals (22.6%). During 36 months, 10 patients from Aza-treated group (29.4%) and seven from MMF-treated group developed DM (17.1%). Serum creatinine values were not significantly different in both arms of the study. Comparison of arterial blood pressure and total cholesterol revealed no significant changes in any of the studied groups. CONCLUSIONS: We conclude that combinations of steroids, tacrolimus, and azathioprine or MMF provide good results with regard to renal function.