A controlled trial comparing two doses of cyclosporine in conjunction with mycophenolate mofetil and corticosteroids

The Efficacy of Rabbit Anti-Thymocyte Globulin for Acute Kidney Transplant Rejection in Patients Using Calcineurin Inhibitor and Mycophenolate Mofetil-Based Immunosuppressive Therapy

Background

T cell depleting antibody therapy with rabbit anti-thymocyte globulin (rATG) is the treatment of choice for glucocorticoid-resistant acute kidney allograft rejection (AR) and is used as first-line therapy in severe AR. Almost all studies investigating the effectiveness of rATG for this indication were conducted at the time when cyclosporine A and azathioprine were the standard of care. Here, the long-term outcome of rATG for AR in patients using the current standard immunosuppressive therapy (i.e., tacrolimus and mycophenolate mofetil) is described.

Material/Methods

Between 2002 to 2012, 108 patients were treated with rATG for AR. Data on kidney function in the year following rATG and long-term outcomes were collected.

Results

Overall survival after rATG was comparable to overall survival of all kidney transplantation patients (P=0.10). Serum creatinine 1 year after rATG was 179 μmol/L (interquartile range (IQR) 136–234 μmol/L) and was comparable to baseline serum creatinine (P=0.22). Early AR showed better allograft survival than late AR (P=0.0007). In addition, 1 year after AR, serum creatinine was lower in early AR (157 mol/L; IQR 131–203) compared to late AR (216 mol/L; IQR 165–269; P<0.05). The Banff grade of rejection, kidney function at the moment of rejection, and reason for rATG (severe or glucocorticoid resistant AR) did not influence the allograft survival.

Conclusions

Treatment of AR with rATG is effective in patients using current standard immunosuppressive therapy, even in patients with poor allograft function. Early identification of AR followed by T cell depleting treatment leads to better allograft outcomes.

Calcineurin inhibitor withdrawal or tapering for kidney transplant recipients

BACKGROUND

Calcineurin inhibitors (CNI) can reduce acute transplant rejection and immediate graft loss but are associated with significant adverse effects such as hypertension and nephrotoxicity which may contribute to chronic rejection. CNI toxicity has led to numerous studies investigating CNI withdrawal and tapering strategies. Despite this, uncertainty remains about minimisation or withdrawal of CNI.

OBJECTIVES

This review aimed to look at the benefits and harms of CNI tapering or withdrawal in terms of graft function and loss, incidence of acute rejection episodes, treatment-related side effects (hypertension, hyperlipidaemia) and death.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Specialised Register to 11 October 2016 through contact with the Information Specialist using search terms relevant to this review. Studies contained in the Specialised Register are identified through search strategies specifically designed for CENTRAL, MEDLINE, and EMBASE; handsearching conference proceedings; and searching the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

All randomised controlled trials (RCTs) where drug regimens containing CNI were compared to alternative drug regimens (CNI withdrawal, tapering or low dose) in the post-transplant period were included, without age or dosage restriction.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility, risk of bias, and extracted data. Results were expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included 83 studies that involved 16,156 participants. Most were open-label studies; less than 30% of studies reported randomisation method and allocation concealment. Studies were analysed as intent-to-treat in 60% and all pre-specified outcomes were reported in 54 studies. The attrition and reporting bias were unclear in the remainder of the studies as factors used to judge bias were reported inconsistently. We also noted that 50% (47 studies) of studies were funded by the pharmaceutical industry.We classified studies into four groups: CNI withdrawal or avoidance with or without substitution with mammalian target of rapamycin inhibitors (mTOR-I); and low dose CNI with or without mTOR-I. The withdrawal groups were further stratified as avoidance and withdrawal subgroups for major outcomes.CNI withdrawal may lead to rejection (RR 2.54, 95% CI 1.56 to 4.12; moderate certainty evidence), may make little or no difference to death (RR 1.09, 95% CI 0.96 to 1.24; moderate certainty), and probably slightly reduces graft loss (RR 0.85, 95% CI 0.74 to 0.98; low quality evidence). Hypertension was probably reduced in the CNI withdrawal group (RR 0.82, 95% CI 0.71 to 0.95; low certainty), while CNI withdrawal may make little or no difference to malignancy (RR 1.10, 95% CI 0.93 to 1.30; low certainty), and probably makes little or no difference to cytomegalovirus (CMV) (RR 0.87, 95% CI 0.52 to 1.45; low certainty)CNI avoidance may result in increased acute rejection (RR 2.16, 95% CI 0.85 to 5.49; low certainty) but little or no difference in graft loss (RR 0.96, 95% CI 0.79 to 1.16; low certainty). Late CNI withdrawal increased acute rejection (RR 3.21, 95% CI 1.59 to 6.48; moderate certainty) but probably reduced graft loss (RR 0.84, 95% CI 0.72 to 0.97, low certainty).Results were similar when CNI avoidance or withdrawal was combined with the introduction of mTOR-I; acute rejection was probably increased (RR 1.43; 95% CI 1.15 to 1.78; moderate certainty) and there was probably little or no difference in death (RR 0.96; 95% CI 0.69 to 1.36, moderate certainty). mTOR-I substitution may make little or no difference to graft loss (RR 0.94, 95% CI 0.75 to 1.19; low certainty), probably makes little of no difference to hypertension (RR 0.86, 95% CI 0.64 to 1.15; moderate), and probably reduced the risk of cytomegalovirus (CMV) (RR 0.60, 95% CI 0.44 to 0.82; moderate certainty) and malignancy (RR 0.69, 95% CI 0.47 to 1.00; low certainty). Lymphoceles were increased with mTOR-I substitution (RR 1.45, 95% CI 0.95 to 2.21; low certainty).Low dose CNI combined with mTOR-I probably increased glomerular filtration rate (GFR) (MD 6.24 mL/min, 95% CI 3.28 to 9.119; moderate certainty), reduced graft loss (RR 0.75, 95% CI 0.55 to 1.02; moderate certainty), and made little or no difference to acute rejection (RR 1.13 ; 95% CI 0.91 to 1.40; moderate certainty). Hypertension was decreased (RR 0.98, 95% CI 0.80 to 1.20; low certainty) as was CMV (RR 0.41, 95% CI 0.16 to 1.06; low certainty). Low dose CNI plus mTOR-I makes probably makes little of no difference to malignancy (RR 1.22, 95% CI 0.42 to 3.53; low certainty) and may make little of no difference to death (RR 1.16, 95% CI 0.71 to 1.90; moderate certainty).

AUTHORS' CONCLUSIONS

CNI avoidance increased acute rejection and CNI withdrawal increases acute rejection but reduced graft loss at least over the short-term. Low dose CNI with induction regimens reduced acute rejection and graft loss with no major adverse events, also in the short-term. The use of mTOR-I reduced CMV infections but increased the risk of acute rejection. These conclusions must be tempered by the lack of long-term data in most of the studies, particularly with regards to chronic antibody-mediated rejection, and the suboptimal methodological quality of the included studies.

Calcineurin Inhibitor Minimization, Conversion, Withdrawal, and Avoidance Strategies in Renal Transplantation: A Systematic Review and Meta-Analysis

Despite their clinical efficacy, concerns about calcineurin inhibitor (CNI) toxicity make alternative regimens that reduce CNI exposure attractive for renal transplant recipients. In this systematic review and meta-analysis, we assessed four CNI immunosuppression strategies (minimization, conversion, withdrawal, and avoidance) designed to reduce CNI exposure and assessed the impact of each on patient and allograft survival, acute rejection and renal function. We evaluated 92 comparisons from 88 randomized controlled trials and found moderate- to high-strength evidence suggesting that minimization strategies result in better clinical outcomes compared with standard-dose regimens; moderate-strength evidence indicating that conversion to a mammalian target of rapamycin inhibitor or belatacept was associated with improved renal function but increased rejection risk; and moderate- to high-strength evidence suggesting planned CNI withdrawal could result in improved renal function despite an association with increased rejection risk. The evidence base for avoidance studies was insufficient to draw meaningful conclusions. The applicability of the review is limited by the large number of studies examining cyclosporine-based strategies and low-risk populations. Additional research is needed with tacrolimus-based regimens and higher risk populations. Moreover, research is necessary to clarify the effect of induction and adjunctive agents in alternative immunosuppression strategies and should include more comprehensive and consistent reporting of patient-centered outcomes.

Impact of the reduction of calcineurin inhibitors on renal function in heart transplant patients: a systematic review and meta-analysis

AIMS

Calcineurin inhibitors (CNIs) taken after heart transplantation lead to excellent short-term outcomes, but long-term use may cause chronic nephrotoxicity. Our aim was to identify, appraise, select and analyse all high-quality research evidence relevant to the question of the clinical impact of CNI-sparing strategies in heart transplant patients.

METHODS

We carried out a systematic review and meta-analysis of randomized controlled trials on CNI reduction in heart transplant recipients. Primary outcomes were kidney function and acute rejection after 1 year. Secondary outcomes included graft loss, all-cause mortality and adverse events.

RESULTS

Eight open-label studies were included, with 723 patients (four tested de novo CNI reduction and four maintenance CNI reduction). Calcineurin inhibitor reduction did not improve creatinine clearance at 12 months 5.46 [-1.17, 12.03] P = 0.32 I(2)  = 65.4%. Acute rejection at 12 months (55/360 vs. 52/332), mortality (18/301 vs. 15/270) and adverse event rates (55/294 vs. 52/281) did not differ between the low-CNI and standard-CNI groups. There was significant benefit on creatinine clearance in patients with impaired renal function at 6 months [+12.23 (+5.26, +18.82) ml min(-1) , P = 0.0003] and at 12 months 4.63 [-4.55, 13.82] P = 0.32 I(2)  = 75%.

CONCLUSIONS

This meta-analysis did not demonstrate a favourable effect of CNI reduction on kidney function, but there was no increase in acute rejection. To provide a better analysis of the influence of CNI reduction patterns and associated treatments, a meta-analysis of individual patient data should be performed.

Impact of the early reduction of cyclosporine on renal function in heart transplant patients: a French randomised controlled trial

BACKGROUND

Using reduced doses of Cyclosporine A immediately after heart transplantation in clinical trials may suggest benefits for renal function by reducing serum creatinine levels without a significant change in clinical endpoints. However, these trials were not sufficiently powered to prove clinical outcomes.

METHODS

In a prospective, multicentre, open-label, parallel-group controlled trial, 95 patients aged 18 to 65 years old, undergoing de novo heart transplantation were centrally randomised to receive either a low (130 < trough CsA concentrations <200 μg/L, n = 47) or a standard dose of Cyclosporine A (200 < trough CsA concentrations <300 μg/L, n = 48) for the three first post-transplant months along with mycophenolate mofetil and corticosteroids. Participants had a stable haemodynamic status, a serum creatinine level <250 μmol/L and the donors' cold ischemia time was under six hours; multiorgan transplants were excluded. The change in serum creatinine level over 12 months was used as the main criterion for renal function. Intention-to-treat analysis was performed on the 95 randomised patients and a mixed generalised linear model of covariance was applied.

RESULTS

At 12 months, the mean (± SD) creatinine value was 120.7 μmol/L (± 35.8) in the low-dose group and 132.3 μmol/L (± 49.1) in the standard-dose group (P = 0.162). Post hoc analyses suggested that patients with higher creatinine levels at baseline benefited significantly from the lower Cyclosporine A target. The number of patients with at least one rejection episode was not significantly different but one patient in the low-dose group and six in the standard-dose group required dialysis.

CONCLUSIONS

In patients with de novo cardiac transplantation, early Cyclosporine A dose reduction was not associated with renal benefit at 12 months. However, the strategy may benefit patients with high creatinine levels before transplantation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00159159.

Immunosuppression: does one regimen fit all?

There has been considerable interest in the individualization of immunosuppressive regimens in an attempt to avoid side effects and improve long-term outcomes. Most available studies have addressed steroid and calcineurin inhibitor minimization in an attempt to prevent the development of chronic allograft dysfunction and cardiovascular mortality. Herein, we evaluate the available evidence for incorporation of these novel strategies in standard clinical care of kidney transplant recipients. Protocol biopsies, pharmacogenetics, and other assays have been developed to guide tailoring of immunosuppression; however, although promising results have been obtained, trials showing their ability to improve long-term outcome are lacking and urgently needed.

Meta-analysis of calcineurin-inhibitor-sparing regimens in kidney transplantation

Calcineurin-inhibitor-sparing strategies in kidney transplantation may spare patients the adverse effects of these drugs, but the efficacy of these strategies is unknown. Here, we conduct a meta-analysis to assess outcomes associated with reducing calcineurin inhibitor exposure from the time of transplantation. We search Medline, Embase, and Cochrane Register of Controlled Trials for randomized controlled trials published between 1966 and 2010 that compared de novo calcineurin-inhibitor-sparing regimens to calcineurin-inhibitor-based regimens. In this analysis, we include 56 studies comprising data from 11337 renal transplant recipients. Use of the contemporary agents belatacept or tofacitinib, in combination with mycophenolate, decreased the odds of overall graft failure (OR 0.61; 95% CI 0.39-0.96; P = 0.03). Similarly, minimization of calcineurin inhibitors in combination with various induction and adjunctive agents reduces the odds of graft failure (OR 0.73; 95% CI 0.58-0.92; P = 0.009). Conversely, the use of inhibitors of mammalian target of rapamycin (mTOR), in combination with mycophenolate, increases the odds of graft failure (OR 1.43; 95% CI 1.08-1.90; P = 0.01). Calcineurin-inhibitor-sparing strategies are associated with less delayed graft function (OR 0.89; 95% CI 0.80-0.98; P = 0.02), improved graft function, and less new-onset diabetes. The more contemporary protocols did not seem to increase rates of acute rejection. In conclusion, this meta-analysis suggests that reducing exposure to calcineurin inhibitors immediately after kidney transplantation may improve clinical outcomes.

Calcineurin inhibitor sparing with mycophenolate in kidney transplantation: a systematic review and meta-analysis

BACKGROUND

Limiting the exposure of kidney transplant recipients to calcineurin inhibitors (CNIs) has potential merit, but there is no clear consensus on the utility of current strategies. In an attempt to aid clarification, we conducted a systematic review and meta-analysis of randomized trials that assessed CNI sparing (minimization or elimination) with mycophenolate as sole adjunctive immunosuppression.

METHODS

The search strategy identified trials where CNI sparing was accompanied by the continuation of, or conversion to, mycophenolate and compared with standard or higher dose CNI therapy. Two investigators independently examined each trial for eligibility, quality, and outcome measures. Additional subgroup analyses were assessed: (1) de novo CNI sparing; (2) elective CNI sparing beyond 2 months posttransplantation; and (3) CNI sparing for transplant dysfunction.

RESULTS

Nineteen randomized controlled trials met the inclusion criteria permitting analysis of 3312 renal transplant recipients with median follow-up of 12 months. CNI sparing significantly improved glomerular filtration rate (weighted mean difference 4.4 mL/min, 95% confidence interval [CI] 2.9-5.9, P<0.001); with some evidence, albeit weak, of improved graft survival (odds ratio 0.72, 95% CI 0.52-1.01, P=0.06). Acute rejection rates were only increased after elective CNI elimination (odds ratio 2.23, 95% CI 1.57-3.17, P<0.001). There were no significant differences in mortality, malignancy or incidence of infections.

CONCLUSIONS

CNI sparing strategies with adjunctive mycophenolate may play an important role in kidney transplant recipients. Improvements in short-term graft function, and possibly graft survival, are achievable. Longer term studies are needed to substantiate the short-term benefits, and refining elective CNI elimination protocols may help to reduce the risk of rejection.

The challenge of renal function in heart transplant children

Renal dysfunction may occur after pediatric heart transplantation and impacts on long-term prognosis. This study aims to review the incidence and mechanisms of chronic nephropathy following heart transplantation, and suggest therapeutic directions. The proportion of pediatric heart-transplant recipients with impaired renal function varies from 22 to 57%, and end-stage renal failure from 3 to 10%, depending on the method used for estimating the glomerular filtration rate. The pathophysiology of renal dysfunction is in part due to calcineurin inhibitor-induced renal vasoconstriction, through activation of the intrarenal renin-angiotensin system, TGF-beta1 upregulation and TGF-beta1 gene polymorphisms. Overproduction of angiotensin II, associated with angiotensin-converting-enzyme genotype, might be associated with poor prognosis and pharmacological factor gene polymorphisms, and may contribute to variation of calcineurine inhibitor exposure in the kidney. Strategies to prevent renal dysfunction include reducing calcineurine inhibitor exposure or delaying calcineurine inhibitor administration from the early post-transplant period. Calcium channel blockers and angiotensin-converting-enzyme inhibitors, blockade of angiotensin II, or anti-TGF-beta1 antibodies might limit nephrotoxicity. No accurate marker can predict the potential of renal lesions to develop. Lowering calcineurine inhibitors levels with immunosuppressive agents that are either less nephrotoxic or non-nephrotoxic should be formally studied. Of high interest is the impact of genetic polymorphism on the development of renal dysfunction.

Relative risk of new-onset diabetes during the first year after renal transplantation in patients receiving tacrolimus or cyclosporine immunosuppression

Clinical trials have consistently shown a higher incidence of new-onset diabetes mellitus with tacrolimus than cyclosporine. However, in protocol-driven studies steroid doses are comparable in both treatment arms, while in clinical practice steroid dose used in conjunction with tacrolimus or cyclosporine may differ. This retrospective study analysed renal transplant recipients without pre-existing diabetes receiving tacrolimus (n = 100) or cyclosporine (n = 100) for whom one-year follow-up data were available. Diabetes was defined as use of insulin or oral hypoglycemic agents; fasting glucose >6.9 mmol/L; or non-fasting glucose >11 mmol/L on three consecutive occasions. Tacrolimus-treated patients were significantly older than cyclosporine-treated patients (49 +/- 14 vs. 44 +/- 13 yr, p < 0.05) and received a significantly lower cumulative dose of corticosteroids over the first three months post-transplant (1284 +/- 379 vs. 1714 +/- 486 mg, p < 0.0001). At 3, 6, 9 and 12 months significantly more tacrolimus-treated patients had new-onset diabetes than cyclosporine- treated patients. At 12 months, 18 patients receiving tacrolimus and two receiving cyclosporine had diabetes (p < 0.0001). There was a clear relationship between age and incidence of new-onset diabetes at three months in the tacrolimus cohort. After stratifying patients by age group, the frequency of diabetes was significantly higher with tacrolimus than with cyclosporine in patients aged 40-60 yr [8/46 (17.4%) vs. 2/48 (4.2%), p < 0.05] and >60 yr [9/28 (32.1%) vs. 0/14 (0%), p < 0.05]. The mean tacrolimus trough level during the first three months was similar in patients with diabetes (13.1 +/- 2.3 ng/mL) or without diabetes (13.0 +/- 2.8 ng/mL, n.s.). These results indicate that new-onset diabetes is strongly and significantly associated with tacrolimus vs. cyclosporine in renal transplant recipients, even when steroid dosing is lower with tacrolimus.

Comparison of sequential protocol using basiliximab versus antithymocyte globulin with high-dose mycophenolate mofetil in recipients of a kidney graft from an expanded-criteria donor

This retrospective pilot study investigated use of high-dose mycophenolate mofetil with biological induction and sequential introduction of low-dose cyclosporine in recipients of expanded criteria donor (ECD) kidneys. Fifty-four patients received mycophenolate mofetil 3 g/day for 45 days, cyclosporine 4 mg/kg/day, prednisolone, and rabbit antithymocyte globulin (rATG, n=14) or basiliximab (n=40). Acute rejection incidence was 11.3% (7.1% with rATG, 12.6% with basiliximab). Delayed graft function was observed in 31 patients (54%). At one year, measured glomerular filtration rate was 54+/-4 ml/min, with no significant differences between induction therapies. Thirty patients (55%) required > or =1 MMF dose reduction within month 1 due to adverse events (gastrointestinal symptoms, 67%; leucopenia 33%). Leucopenia was more frequent with rATG, while gastrointestinal symptoms were more frequent with basiliximab. Cytomegalovirus replication occurred in three patients (23%) with rATG and 3 (8%) with basiliximab. In conclusion, high-dose MMF, corticosteroids, delayed low-dose cyclosporine and induction therapy offers an excellent risk-to-benefit ratio in patients receiving an ECD allograft.

Basiliximab lowers the cyclosporine therapeutic threshold in the early post-kidney transplant period

Early adequate cyclosporine exposure has been shown to predict low acute rejection rate in kidney transplantation. The aim of this study is to determine the importance of exceeding the early cyclosporine therapeutic exposure threshold with basiliximab induction. A retrospective analysis of 166 first cadaveric and non-identical live donor transplant recipients treated with or without basiliximab induction, Neoral, mycophenolate mofetil and prednisone, was performed. Adequate exposure was defined as a 2-h post-Neoral dose cyclosporine level (C2) >1700 ng/mL at day 3. The primary outcome was acute rejection within the first 6 months. In the no basiliximab (control) group (n = 74), rejection occurred in 23% (17 of 74) of recipients and was strongly associated with low cyclosporine exposure on day 3. Acute rejection occurred in 38% (11 of 29) with C2 <1700 ng/mL compared with 13% (six of 45) with C2 >/=1700 ng/mL (p = 0.014). In the basiliximab group (n = 92), rejection occurred in only 11% (10 of 92) of recipients and did not correlate with cyclosporine exposure. Acute rejection occurred in 10% (four of 40) with C2 <1700 ng/mL compared with 12% (six of 52) with C2 >/=1700 ng/mL (p = 0.81). Therefore achieving cyclosporine therapeutic targets by day 3 may not be required when anti-IL2 receptor antibody induction is used.

Improved Clinical Outcomes in Chinese Renal Allograft Recipients Receiving Lower Dose Immunosuppressants

BACKGROUND

The application of potent immunosuppressants has decreased the incidence of acute rejection and increased short- and long-term graft survival; however, these drugs cause a variety of complications. In China, many transplant centers have adopted the immunosuppressive protocols based on the white population, neglecting the differences between the races. The purpose of this study was to explore a suitable immunosuppressive regimen for Chinese renal allograft recipients.

METHODS

Two hundred cadaveric renal allograft recipients who underwent transplantation between July 1999 and October 2001 were observed. Before October 2000, 104 recipients received the conventional dose of immunosuppressants; thereafter, 96 recipients received lower dose treatment. Doses of immunosuppressive agents, the incidence of acute rejection and pulmonary infection, and patient and graft survival rates were compared between the two groups.

RESULTS

Doses of mycophenolate mofetil (MMF) and cyclosporine A (CsA) administered in the conventional dose group were significantly higher than in the lower dose group at 3 months posttransplant, as was prednisone at 6 months posttransplant. The incidence of acute rejection and subclinical rejection that was biopsy-proven or diagnosed by clinical manifestations was 17.3% and 19.8%, respectively, in the conventional dose group and the lower dose group within the first 6 months, and no significant difference was noted (P=0.55). The incidence of pulmonary infection, especially severe infection, was much higher in the conventional treatment group (40.1% and 26.9%, respectively) than that in the lower dose group (11.5% and 5.2%, respectively), and the differences were statistically significant (P<0.001). The corresponding 1-year survival rate of patients was 87.4% and 97.9% (P<0.01), and that of renal grafts was 85.5% and 96.9% (P<0.01), for patients receiving conventional dose and lower dose immunosuppressive drugs, respectively. The rate of death with a functioning allograft caused by infection in the conventional dose group was significantly higher than that in the lower dose group (12.5% vs. 0%, P<0.01).

CONCLUSIONS

The regimen of lower dose MMF, CsA, and prednisone in combination can significantly reduce the incidence of pulmonary infection, especially severe pulmonary infection, without increasing the incidence and severity of allograft rejection.

Therapy for acute rejection in pediatric organ transplant recipients

Despite the availability of potent immunosuppressive drugs, rejection after organ transplantation in children remains a serious concern, and may lead to significant morbidity, graft loss, and death of the patient. Acute graft rejection in pediatric recipients is first treated with methylprednisolone pulses, followed by progressive taper of corticosteroid doses. After control of the rejection episode, baseline immunosuppression has to be adjusted and closely monitored since rejection (especially late episodes, occurring more than 6 months after transplantation) may be due to a lack of compliance or sub-therapeutic drug concentrations. The management of corticosteroid resistant rejection is not standardized, and depends on the transplanted organ and previous immunosuppressive regimen. In patients experiencing corticosteroid resistant acute rejection while on a cyclosporine-based immunosuppressive regimen, cyclosporine is generally changed to tacrolimus. In case of tacrolimus-based immunosuppression, tacrolimus blood levels may be increased, and/or mycophenolate mofetil (which nowadays tends to replace azathioprine) or sirolimus may be added, although pharmacodynamic data and clinical studies with these agents are still scarce in pediatric recipients. The use of antithymocyte globulins or monoclonal anti-CD3 antibodies, muromonab CD3 (OKT3) is hampered by numerous adverse effects, including a significant risk of over-immunosuppression. These therapies are nowadays indicated in very selected cases. Other treatments such as plasmapheresis and high dose immunoglobulins may be useful in difficult cases. In patients with refractory rejection despite therapeutic escalation, the risks of over-immunosuppression, including opportunistic infections and malignancies (especially the Epstein-Barr virus related post-transplant lymphoproliferative disease) have to be balanced with the consequences of graft loss due to rejection. Detransplantation or retransplantation may, in some instances, be preferable to severe infectious or tumoral complications.

Withdrawal of cyclosporine or prednisone six months after kidney transplantation in patients on triple drug therapy: a randomized, prospective, multicenter study

Uncertainty exists regarding the necessity of continuing triple therapy consisting of mycophenolate mofetil (MMF), cyclosporine (CsA), and prednisone (Pred) after kidney transplantation (RTx). At 6 mo after RTx, 212 patients were randomized to stop CsA (n = 63), stop Pred (n = 76), or continue triple drug therapy (n = 73). The MMF dose was 1000 mg twice daily, target CsA trough levels were 150 ng/ml, and Pred dose was 0.10 mg/kg per d. Follow-up was until 24 mo after RTx. Biopsy-proven acute rejection occurred in 14 (22%) of 63 patients after CsA withdrawal compared with 3 (4%) of 76 in the Pred withdrawal group (P = 0.001) and 1 (1.4%) of 73 in the control group (P = 0.0001). Biopsy-proven chronic rejection was present in one patient in the control group, in nine patients after CsA withdrawal (P = 0.006 versus control group); and in four patients after discontinuation of Pred (NS). Graft loss occurred in two versus one patient after CsA or Pred withdrawal, respectively, and in two patients in the control group (NS). Patients who successfully withdrew CsA had a significantly lower serum creatinine during follow-up. Pred withdrawal resulted in a reduction in mean arterial pressure, and the total cholesterol/HDL ratio increased. In conclusion, rapid CsA withdrawal at 6 mo after RTx results in a significantly increased incidence of biopsy-proven acute and chronic rejection. Pred withdrawal was safe and resulted in a reduction in mean arterial pressure. However, patient and graft survival and renal function 2 yr after RTx were not different among groups.