Safety assessment of the conversion from mycophenolate mofetil to enteric-coated mycophenolate sodium in stable renal transplant recipients

The immunosuppressant mycophenolate mofetil (MMF; CellCept) has greatly improved transplant recipients' clinical outcomes, but its efficacy may be limited by dose adjustments due to adverse events (AEs). An enteric-coated formulation of mycophenolate sodium (EC-MPS; myfortic), designed to improve gastrointestinal tolerability is now available. This Latin-American, prospective, multicenter, open-label, 6-month trial assessed the safety and tolerability of converting renal transplant recipients from MMF to EC-MPS. In total, 237 renal transplant recipients (stable > or = 3 months' posttransplant) receiving MMF (< or =1000 mg b.i.d.) were enrolled. Adults (n = 218) were converted to EC-MPS 720 mg b.i.d. (equimolar to MMF 1000 mg b.i.d.) even if they were initially receiving <1000 mg MMF b.i.d. (ie, 47 adults received a higher than equimolar dose of EC-MPS). Children (n = 19) were converted to EC-MPS 450 or 432 mg/m2 b.i.d. Patients also received cyclosporine microemulsion (Neoral) and corticosteroids. There were three acute rejections and no graft failures. The incidence of AEs was 59.9% (in those receiving a higher than equimolar EC-MPS dose it was 57.4%). In all, 22% of patients had gastrointestinal AEs, 37% had infections, and 4.8% had hematological AEs. Only 24 patients (10%) had an AE-related dose reduction. Seven of these patients had received higher than equimolar doses of EC-MPS. Patients can be safely converted from different doses of MMF to a standard dose of EC-MPS. The requirement for EC-MPS dose reduction to manage AEs was relatively low. Use of EC-MPS is a valid alternative for renal transplant recipients receiving maintenance MMF treatment.     

Pharmacokinetics of mycophenolate mofetil in stable pediatric liver transplant recipients receiving mycophenolate mofetil and cyclosporine.

There are few pharmacokinetic data for mycophenolate mofetil (MMF) when used in combination with cyclosporine (CsA) in pediatric liver transplant recipients. The aim of this study was to assess the pharmacokinetics of MMF in stable pediatric liver transplant patients and estimate the dose of MMF required to provide a mycophenolic acid (MPA) exposure similar to that observed in adult liver transplant recipients receiving the recommended dose of MMF (target area under the plasma concentration-time curve from 0 to 12 hours [AUC(0-12)] for MPA of 29 mug.hour/mL in the immediate posttransplantation period and 58 microg x hour/mL after 6 months). A 12-hour pharmacokinetic profile was collected for 8 pediatric patients (mean age 20.9 months) on stable doses of MMF and CsA who had received a liver transplant > or = 6 months prior to entry and who had started on MMF within 2 weeks of transplantation. Mean MMF dosage was 285 mg/m(2) (range, 200-424 mg/m(2)). Of 8 patients, 7 had a MPA AUC(0-12) (range, 11.0-37.2 microg x hour/mL) well below the target. One patient had an AUC(0-12) > or = 58 microg x hour/mL but was considered an outlier and was excluded from analyses. Mean MPA AUC(0-12) and maximum plasma concentration values were 22.7 +/- 10.5 microg x hour/mL and 7.23 +/- 3.27 microg/mL, respectively; values normalized to 600 mg/m(2) (the approved pediatric dose in renal transplantation) were 47.0 +/- 21.8 microg x hour/mL and 14.5 +/- 4.21 microg/mL. In conclusion, assuming that MPA exhibits linear pharmacokinetics, when used in combination with CsA, a MMF dose of 740 mg/m(2) twice daily would be recommended in pediatric liver transplant recipients to achieve MPA exposures similar to those observed in adult liver transplant recipients. This finding should be confirmed by a prospective trial.     

Conversion to mycophenolate mofetil in conjunction with stepwise withdrawal of cyclosporine in stable renal transplant recipients

BACKGROUND: Mycophenolate mofetil (MMF) is now part of standard immunosuppression in the first phase after renal transplantation. A relevant question is if it can replace drugs such as cyclosporine (CsA) in the maintenance treatment, improving cardiovascular risk profile. METHODS: In 17 patients with a stable renal function (at least 6 months) posttransplantation, we studied the effect of CsA replacement by MMF. After starting MMF (1 g b.i.d.), CsA dosage was reduced from regular to low (median trough level 130 microg/L, respectively, 45 microg/L), followed by complete withdrawal, while prednisone (7.5 mg daily) was continued. We measured ambulatory blood pressure, glomerular filtration rate, renal plasma flow, renal vascular resistance, and metabolic factors at start and after 8 weeks on regular, low-dose CsA, respectively, no CsA with MMF and prednisone. RESULTS: Two patients dropped out after the switch to low-dose CsA/MMF, due to diarrhea in one and a steroid responsive rejection in the other. The complete switch from CsA to MMF was successful in all 15 patients and accompanied by a decrease in 24 hr systolic blood pressure (from 152+/-13 to 145+/-13 mmHg; P<0.01), diastolic blood pressure (93+/-9 to 89+/-12 mmHg; P<0.05), RVR (0.29+/-0.06 to 0.25+/-0.09 mmHg.ml/min; P<0.05), and an increase in glomerular filtration rate (46.6+/-8.8 to 58.0+/-10.5 ml/min; P<0.01) and renal plasma flow. Intermediate low density lipoprotein-cholesterol decreased (0.79+/-0.37 to 0.41+/-0.16 mmol/L; P<0.01). High density lipoprotein-cholesterol decreased, but remained in the safe range. After 1 year two patients stopped the MMF; one because of Kaposi's sarcoma and one because of recurrent infections CONCLUSIONS: The stepwise switch from CsA to MMF was safe and mostly successful, and had beneficial effects on blood pressure, glomerular hemodynamics, and lipid profile. Beneficial trends were already present after partial withdrawal of CsA.     

Cyclosporine-sparing effect of basiliximab in renal transplant recipients with mycophenolate mofetil

Basiliximab added to a maintenance regimen consisting of cyclosporine microemulsion and mycophenolate mofetil was studied for its effectiveness in allowing early steroid withdrawal in renal transplantation. Furthermore, the cyclosporine-sparing effects between groups with and without basiliximab induction therapy were compared. PATIENTS: Between September 2001 and June 2003, 90 patients underwent renal transplants with cyclosporine-based immunosuppression, namely, cyclosporine, mycophenolate mofetil, and methylprednisolone, (group 1; n = 25). During the latter half of the study basiliximab was administered during the induction phase (group 2; n = 65). In group 2, steroids were completely withdrawn on postoperative day 14 in 57 patients. RESULTS: The incidence of acute rejection was significantly higher among group 1 patients (P = .005). The incidence of steroid-resistant rejection in group 1 patients was significantly higher (P = .025). At each time point cyclosporine levels in group 1 patients were significantly higher (P < .01). The incidence of infection was comparable between the groups. Patient and graft survival rates in group 1 were 100% and 100%; in group 2, they were 99% and 99%, respectively. In group 2, steroids were discontinued in 57 patients with permanent withdrawal achieved in 32 patients (56%). CONCLUSION: The use of basiliximab, together with mycophenolate mofetil allowed for a significant reduction in the cyclosporine dose without increasing the risk of acute rejection. Although further follow-up is necessary to confirm the effect, this regimen may attenuate cyclosporine nephrotoxicity thereby affecting the long-term outcomes of renal transplantation.     

Elective withdrawal of mycophenolate mofetil in renal transplant recipients treated with mycophenolate mofetil, cyclosporine, and prednisone

In a retrospective study we investigated the risk of acute rejection after the withdrawal of mycophenolate mofetil (MMF) in 39 adult patients treated with cyclosporine (CyA), prednisone, and MMF for at least 6 months following renal transplantation. After reaching a stable renal graft function, MMF was withdrawn and CyA and prednisone were continued. Preceding the withdrawal of MMF, four patients experienced an acute rejection. During a median follow-up of 38 months after discontinuing MMF, no acute rejection occurred. The mean serum creatinine level did not change during the first 6 months after withdrawal of MMF. We conclude that elective withdrawal of MMF in stable renal transplant recipients at 6 months after transplantation bears no important risk of an occurrence of acute rejection. Received: 24 November 1999 Revised: 11 May 2000 Accepted: 18 December 2000     

Measurement of mycophenolate mofetil effect in transplant recipients

BACKGROUND: Immunosuppression involves the nature of the immunosuppressive agents and individual differences in patient factors. We investigated whether the effect of mycophenolate mofetil (MMF) is measurable using an in vitro measure of immunocompetence and related its effects to cyclosporine (CsA) in vitro. METHODS: Liver or kidney transplant recipients receiving prednisone; CsA or tacrolimus; and MMF, azathioprine (AZA), or neither, were studied. Immunocompetence was assessed by one-way mixed lymphocyte culture using patients' peripheral blood leukocytes (PBL) and three validated stimulators. The effect of immunosuppressive agents added in vitro on normal PBL stimulation by Staphylococcus enterotoxin B was determined by the carboxyfluorescein diacetate succinimidyl ester measurement of division. RESULTS: Patients receiving MMF had an average immunocompetence level of 12+/-23, compared with 39.7+/-65 and 25.5+/-42 for those receiving AZA or neither AZA nor MMF, respectively. Thus, there was an approximately 80% suppression of the response in the MMF group. Assessment of normal cell division revealed that CsA allowed multiple cell generations but suppressed the numbers of cells in each, whereas MMF blocked proliferation into subsequent generations. Addition of clinically relevant levels of mycophenolic acid, the active agent for MMF, added to more moderate levels of CsA, was required to achieve greater than 80% suppression, consistent with the degree of immunocompetence depression measured in patients. CONCLUSIONS: These data provide the novel finding that the effect of MMF treatment on patients is measurable in their PBL as decreased immunocompetence in vitro. The effect of MMF on normal PBL approximates the 80% inhibition that we found in patients. Moreover, the effect of MMF on cell division provides a rationale for the superior effectiveness of regimens including MMF.     

Comparative pharmacokinetic study of two mycophenolate mofetil formulations in stable kidney transplant recipients

We compared steady-state pharmacokinetics of mycophenolate mofetil (MMF) - Myfenax(?) (Teva) and CellCept(?) (Roche) - in stable kidney transplant recipients (KTRs). This was an international, multi-centre, randomized, open-label, two-treatment, two-sequence crossover study with a 3-month follow-up. We included KTRs at least 12 months post-transplantation with stable renal graft function for at least 3 months. The maintenance treatment consisted of MMF in combination with tacrolimus with or without steroids. At the end of the two treatment periods, 6-h or 12-h PK studies of mycophenolic acid (MPA) were performed. A total of 43 patients (mean age: 50.7 ± 13.5 years; 19 females, 24 males) were randomized. Estimates of test to reference ratios (90% CIs) were 0.959 (0.899; 1.023) h*μg/ml for AUC((0-tau)) and 0.873 (0.787; 0.968) μg/ml for C(max). Estimates for AUC((0-6h)) were 0.923 (0.865; 0.984) h*μg/ml and 0.985 (0.877; 1.106) μg/ml for C(min). Thus, AUC((0-tau)), AUC((0-6h)), and C(min) of MPA were within the predefined margins. C(max) was somewhat outside of these margins in this set of patients. The numbers and types of adverse events were not different between the two treatments. The steady-state pharmacokinetics of MPA as well as adverse events are comparable for Myfenax(?) and CellCept(?) in tacrolimus-treated stable KTRs.     

A comparison of mycophenolate mofetil with mycophenolate sodium in renal transplant recipients on tacrolimus-based treatment

We compared the tolerability and efficacy of mycophenolate mofetil (MMF) versus mycophenolate sodium (MPS) among renal transplant recipients on tacrolimus-based immunosuppression. The 105 patients who underwent kidney transplantation between January 2002 and March 2008 and were treated with steroid, tacrolimus, and a mycophenolic acid compound were enrolled in the study. From patient files we collected on demographics data, donors, immunosuppressive drug doses, biochemical and hematologic parameters, gastrointestinal and hematologic side effects, and kidney function. Fifty-six patients were prescribed MMF and 49 of them were taking MPS. Demographic parameters and pretransplantation dialysis duration were similar between the 2 groups. After the third month, the MPS dose was higher than that of MMF. There were no clinically important differences between the 2 groups, regarding other immunosuppressive drug doses. Gastrointestinal side effects were similar: 42.4% in the MMF versus 44.8% in the MPS group (P = .846). Six patients in the MMF group and 1 patient in the MPS group underwent a switch of the mycophenolic acid therapy due to severe gastrointestinal side effects (P = .183). Biopsy-proven acute rejection was reported in 6 patients on MMF and 7 patients on MPS therapy (P = .768). The log-rank test evaluating a 50% reduction in glomerular filtration rate (GFR) showed no significant difference between the 2 groups (P = .719). No deaths were recorded during the study period; there was only 1 graft loss, which occurred in the MMF group. We did not observe a significant difference in tolerability and efficacy between the 2 widely used mycophenolic acid derivatives. Economic considerations can be an important factor when choosing the drug.     

吗替麦考酚酯与麦考酚钠肠溶片对肾移植受体血药浓度的影响

目的  探讨吗替麦考酚酯（MMF）与麦考酚钠肠溶片（EC-MPS）在同等生物效应剂量下对肾移植受体麦考酚酸（MPA）血药浓度和不良反应的影响。方法  回顾性分析106例活体供肾移植受体的临床资料。按肾移植术后服用不同药物分为两组,MMF组（M1组,62例）和EC-MPS组（M2组,44例）。两组受体的免疫抑制方案分别为M1组用他克莫司（FK506）+MMF+泼尼松,M2组用FK506+EC-MPS+泼尼松。分析两组受体服药后1、2、3周和1、2、3个月MPA血药浓度的变化情况、不良反应发生情况及服用药物所花费用。结果  采取同等生物效应给药,服药后第1、2、3周,第1、2、3个月时M1组MPA血药谷浓度比M2组低,各个时间点两组间比较,差异均有统计学意义（均为P < 0.05）。与M1组比较,M2组术后不良反应的发生率较低且症状较轻。采用同等生物学效应给药,M1组服用MMF所花费用1 710元/月,M2组服用EC-MPS所花费用2 736元/月,但M1组因治疗药物不良反应所产生费用远高于M2组。结论  同等的生物效应剂量下服用EC-MPS的患者相对服用MMF的患者能维持更高的MPA血药浓度并且不良反应更少。     

Primary immunosuppression with tacrolimus and low-dose mycophenolate mofetil in renal transplant recipients

Both tacrolimus and mycophenolate mofetil (MMF) are potent immunosuppressive agents used in combination for prevention of acute rejection in renal transplantation. We studied the efficacy and safety of tacrolimus/MMF-based primary immunosuppression as well as their pharmacokinetics (PK) in Chinese renal transplant recipients. Oral tacrolimus was initiated at about 0.2 mg/kg/d, dose which was adjusted to achieve target trough levels of 10 to 20 ng/mL at 3 months and 5 to 10 ng/mL thereafter. The patients also received MMF (0.5 g bid) and prednisolone. PK profiles were studied at 1 week, and 1, 3, and 6 months posttransplant. Blood samples were taken at 0 (predose), 20, 40, 60, 75, and 90 minutes and 2, 4, 6, 8, 10, and 12 hours postdose for each profile. Plasma MPA and whole blood tacrolimus levels were determined by HPLC and EMIT methods respectively. Eight patients were studied with mean follow-up of 16.1 +/- 2.4 months. One patient (12.5%) experienced a borderline acute rejection episode. Both 1-year graft and patient survival rates were 100%. Posttransplant diabetes, diarrhea, and hand tremor occurred in 12.5%, 12.5%, and 37.5%, respectively. No patient had an opportunistic infection. Tacrolimus trough concentrations showed a fair correlation with AUC(0-12h) (R(2) = 0.587). Mean MPA AUC values at 1, 3, and 6 months were 40.5 +/- 9.4, 44.4 +/- 17.3, and 57.2 +/- 20.7 mug*h/mL, respectively (P = .0486, n = 7). In conclusion, primary immunosuppression with tacrolimus, low-dose MMF (0.5 g bid), and prednisolone is effective and safe with adequate systemic MPA exposure in renal transplant recipients.     

Pharmacokinetics and pharmacodynamics of mycophenolic acid in stable renal transplant recipients treated with low doses of mycophenolate mofetil

Abstract Suboptimal doses of mycophenolate mofetil (MMF) are frequently employed in renal transplant (Tx) patients, with drug‐related side effects or low weight. The aim of this study was to compare the mycophenolic acid (MPA) pharmacokinetic profile and its pharmacodynamic effect on patients receiving either standard (2 g) or low (1.5 g or 1 g) MMF doses, in order to evaluate the therapeutic efficacy of such low doses in inhibiting IMPDH activity. Twenty‐seven stable renal Tx recipients aged 18‐65 years, with a post‐Tx follow‐up of 38.5 ± 44.8 months (6‐166 months), receiving 1 g (n = 10), 0.75 g (n = 7) and 0.5 g (n = 10) MMF twice a day in association with cyclosporine and prednisone, were included. The control group was made up of untreated healthy volunteers (n = 5). Plasma concentrations of MPA were analyzed by reverse‐phase HPLC. IMPDH activity was determined in lymphocytes by the measurement of ³H release from [2,8‐³H] hypoxantine. The mean value of areas under the concentration‐time curves (AUC_0‐12) of MPA throughout the 12‐h dosing interval in patients treated with 2 g was higher than the corresponding data in patients receiving 1.5 g or 1 g bid, but no statistical differences were observed between the three groups. There was no correlation between MPA‐AUC_0‐12 values and MMF dose (expressed in g/day or g/kg per day). Predose MPA concentrations correlated only weakly with the respective MPA‐AUC_0‐12 values (r² from 0.385 to 0.655), whereas an acceptable correlation was observed between MPA C_max and MPA‐AUC_0‐12 (r² from 0.626 to 0.759) in 2 g, 1.5 g, and 1 g MMF groups. An inverse relationship between MPA concentrations and IMPDH activity was observed. In general, the maximum MPA concentration was achieved from 1 h to 2 h after dosing, and the maximum inhibition of IMPDH was also from 1 h to 2 h after dosing. The evaluation of IMPDH activity demonstrated that there was a significant statistical difference between samples from 0 to 1 h (P = 0.008) and 0 to 2 h (P = 0.04). In conclusion, concentration‐time profiles of renal transplant recipients administered 0.75 g and 0.5 g twice a day are slightly lower than those from the 2 g group, but nor significantly. On the other hand, inhibition of IMPDH activity was comparable in the three groups, indicating considerable interindividual pharmacodynamic variability. Pharmacodynamic monitoring of the degree of immunosuppression and its correlation with MPA plasma concentrations will be assessed further in future studies.     

Quality of life in renal transplant recipients following conversion from mycophenolate mofetil to enteric-coated mycophenolate sodium

INTRODUCTION: Tolerance to immunosuppresant treatment has considerable impact on adherence to therapy and on the outcome of renal transplantation. Recent data indicate better gastrointestinal tolerance to enteric-coated mycophenolate sodium (EC-MPS) than to the classic mycophenolate mofetil (MMF) formulation. AIM: This study assessed the effect of conversion therapy from MMF to EC-MPS on gastrointestinal tolerance and quality of life in renal transplant recipients. METHODS: This open observational study analyzed the outcomes of conversion from MMF to EC-MPS among renal transplant patients with gastrointestinal complaints. At baseline (B) and at 8 weeks postconversion patients were assessed by the Gastrointestinal Quality of Life Index (GIQLI) questionnaire as well as by clinical evaluation (acute rejection, infection) and analytical determinations. RESULTS: We analyzed 18 recipients of cadaveric renal transplants of mean age of 54 +/- 9 years including 61% men and one retransplant. Our patients had stable renal function with mean creatinine of 1.9 +/- 0.7 mg/dL. Baseline treatment included cyclosporine-MMF-prednisone (33%) or FK-MMF-prednisone (66%). Bioequivalent conversion was carried out at 50 +/- 29 months posttransplantation. Conversion to EC-MPS resulted in an improvement in overall quality of life (total score: baseline 106.61 vs 8 weeks 116.89; P < .01). Improvements were observed in the following GIQLI subscales: gastrointestinal symptoms (3.12 vs 3.48, P < .001), physical function (2.54 vs 2.76, P = .003), medical treatment (2.17 vs 2.50, P = .031), and emotion (3.08 vs 3.39, P = .001). No changes were observed in the social function subscale. The hemogram and renal function remained stable; there were no episodes of rejection or infection. CONCLUSION: Conversion from MMF to an EC-MPS formulation was associated with improvements in gastrointestinal complaints and quality of life among renal transplant recipients.