Addition of Sirolimus to Cyclosporine in Long-Term Kidney Transplant Recipients to Withdraw Steroid

A prospective, multinational pharmacoepidemiological study of clinical conversion to sirolimus immunosuppression after renal transplantation

This prospective pharmacoepidemiological study examined treatment and outcomes in patients converted to sirolimus (SRL) after renal transplantation. 484 subjects in 36 centres in 7 countries were followed for up to 5 years. Principal reasons for conversion were declining graft function (146/484, 30%) and side effects of prior therapy (144/484, 30%) and the major treatment combinations after conversion were SRL ± MMF (62%), SRL + TAC (21.5%), SRL + CSA (16.5%). The cumulative probability of biopsy-confirmed acute rejection (BCAR) was 5% (n = 22), death-censored graft loss 12% (n = 56) and death 6% (n = 22), and there was no significant relationship to the treatment combination employed. Median calculated creatinine clearance was 48.4 (29.3, 64.5) mL/min at conversion, rising to 54.1 (41.2, 69.0) mL/min at month 1, 55.7 (39.0, 73.0) mL/min at month 12, 58.6 (39.7, 75.2) mL/min at two years and 60.9 (36.0, 77.0) mL/min at three years post-conversion. The most common adverse events were hypertension (47%), hyperlipidemia (26%), urinary tract infections (25%), anaemia (24%) and diarrhea (14%), and cardiac events, hyperlipemia and CMV infection were more common in patients converted during the first year. SRL was most frequently combined with MMF after conversion, but principal clinical outcomes were not significantly influenced by the treatment combination employed in normal practice.

Prospective observational study of sirolimus as primary immunosuppression after renal transplantation

BACKGROUND.: Sirolimus (SRL) is an important component of clinical immunosuppression in renal transplantation, but few international studies have examined how this agent is used in routine practice. METHODS.: Within a large prospective pharmacoepidemiological study, 718 de novo renal graft recipients treated with SRL in 65 centers in 10 countries were monitored for up to 5 years posttransplant to compare the principal outcomes and adverse effects by treatment regimen. RESULTS.: Principal treatment regimens were SRL without a calcineurin inhibitor (33%), SRL+cyclosporine A (CsA) (33%), and SRL+tacrolimus (TAC) (34%); 18% of subjects discontinued SRL, 124/718 (17%) developed biopsy-confirmed acute rejection (BCAR), 64/718 (9%) lost their graft, and 50/718 (7%) died during follow-up. Calculated creatinine clearance was 66+/-26 mL/min at 2 years. The most common adverse events were hypertension, hyperlipidemia, anemia, urinary tract infections, and diabetes. BCAR was significantly lower in subjects receiving SRL+TAC (hazard ratio [HR] 0.46, P=0.009) but not significantly lower in those receiving SRL+CsA (HR 0.62, P=0.102) compared with SRL without a calcineurin inhibitor. Graft loss or death did not significantly differ between treatment groups but were associated, respectively, with deceased donor grafts (HR 3.33, P<0.001) and increased age (HR 1.04, P<0.001). No improvement was observed in patients receiving mycophenolate mofetil in any treatment combination (HR 0.80, P=0.438 for BCAR; HR 0.93, P=0.849 for graft loss; and HR 0.75, P=0.531 for death). CONCLUSIONS.: SRL is most commonly used in combination with mycophenolate mofetil, CsA, or TAC. BCAR was least common in subjects receiving SRL+TAC, but other outcomes seemed comparable between the treatment regimens in routine practice.

Steroid avoidance or withdrawal for kidney transplant recipients

BACKGROUND

Steroid-sparing strategies have been attempted during the last two decades in order to avoid morbidity in kidney transplant recipients. Previous systematic reviews of steroid withdrawal after kidney transplantation have shown significant increases in acute rejection and an increase in graft failure rates. Steroid avoidance in kidney transplantation is increasingly attempted and the possible benefits or harms have never been a subject of a systematic review.

OBJECTIVES

To assess the safety and efficacy of steroid withdrawal or avoidance in patients receiving a kidney transplant.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE and EMBASE, references lists and abstracts from international transplantation society scientific meetings.

SELECTION CRITERIA

Randomised controlled studies (RCTs) of steroid avoidance or withdrawal were included providing that one treatment arm consisted in steroid avoidance or withdrawal and intention-to-treat rates of acute rejection and graft failure were clearly established after steroid avoidance or use or withdrawal or continuation. Observational studies were tabulated.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted data. Statistical analyses were performed using the random effects model and results expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

MAIN RESULTS

We included 30 RCTs (5949 participants). Steroid-sparing strategies showed no effect on mortality or graft loss including death. Patients on any steroid-sparing strategy showed a higher risk of graft loss excluding death than those with conventional steroid use (RR 1.23, 95% CI 1.00 to 1.52), especially in those not receiving MMF/Myf or everolimus (RR 1.70, 95% CI 1.00 to 2.90). Acute rejection was more frequent with a steroid-sparing strategy (RR 1.27, 95% CI 1.14 to 1.40) and more frequent after steroid withdrawal or avoidance when compared with standard steroid treatment when cyclosporin (CsA) was used. Steroid-sparing and withdrawal strategies showed benefits in reducing antihypertensive drug need, serum cholesterol, antihyperlipidaemic drug need, new-onset diabetes after transplantation (NODAT) requiring any treatment and cataracts. Steroid avoidance did not alter serum cholesterol, but was associated with less frequent NODAT requiring any treatment. Cardiovascular events were reduced with steroid avoidance. Reduced antihypertensive drug need and serum cholesterol were similar with CsA or tacrolimus (TAC). Reduced antihyperlipidaemic drug need was only evident with TAC, whereas the reduction in NODAT requiring any treatment was only evident with CsA. Infection was lower in steroid-sparing patients using CsA (RR 0.88, 95% CI 0.78 to 1.00). NODAT requiring any treatment was less frequent with steroid avoidance than with steroid withdrawal.

AUTHORS' CONCLUSIONS

This review confirms that steroid avoidance and steroid withdrawal strategies in kidney transplantation are not associated with increased mortality or graft loss despite an increase in acute rejection. These immunosuppression strategies may allow safe steroid avoidance or elimination a few days after kidney transplantation if antibody induction treatment is prescribed or after three to six months if such induction is not used.

Minimization of steroids in kidney transplantation

The goal of steroid minimization trials has been to minimize or eliminate steroid-related side-effects while simultaneously not increasing the rate of acute rejection (AR) and chronic graft loss. Early trials of late steroid withdrawal (> or =3 months post-transplant) were associated with significantly increased AR rates and late graft loss. More recent trials of rapid discontinuation of prednisone (RDP) (< or =7 days post-transplant) have been associated with little or no increase in AR rates and no difference in graft survival (versus maintenance prednisone). Of note, induction therapy appears to be important for success; however, it is not clear if any single maintenance protocol is superior. Intermediate-term follow-up (5-7 years) is now available for some randomized and nonrandomized trials; graft survival and renal function remain excellent. Most of these trials have been done in low immunologic risk recipients, but there are reports of success of RDP in children, black recipients, sensitized recipients, recipients with potentially recurring disease, and kidney-pancreas recipients. Of critical importance, steroid-related side-effects have been minimized. Steroid minimization protocols can clearly be recommended for low-risk patients; additional trials are necessary for those at higher risk. Additional research is also necessary on integrating calcineurin inhibitor minimization with steroid minimization.

Steroid elimination-who, when, how?

Steroids have numerous side effects, many occurring early posttransplantation with relatively low prednisone doses. Consequently, investigators have attempted steroid minimization or withdrawal. The first attempts at steroid minimization used early low-dose steroids and were associated with an increased rate of acute rejection episodes, late graft dysfunction, and graft loss. Subsequent studies, with cyclosporine-based immunosuppression, attempted steroid withdrawal late posttransplantation (>3 months) in highly selected, clinically well, and immunologically low-risk recipients. Again, steroid withdrawal was associated with an increased risk of acute rejection episodes and these episodes were associated with graft dysfunction and increased graft loss. The development of new powerful immunosuppressive agents has led to renewed attempts at late prednisone withdrawal. These also have been associated with increased late rejection risk. A more exciting innovation has been the attempts at rapid discontinuation ( Collapse

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MESH Headings

• Adrenal Cortex Hormones/adverse effects
• Antilymphocyte Serum/therapeutic use
• Clinical Trials as Topic
• Drug Administration Schedule
• Drug Therapy, Combination
• Graft Rejection/epidemiology
• Graft Rejection/prevention & control
• Graft Survival/drug effects
• Graft Survival/physiology
• Humans
• Immunosuppressive Agents/therapeutic use
• Kidney Transplantation/immunology
• Prednisone/adverse effects

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Grants

• P01 DK013083 NIDDK NIH HHS
• DK 13083 NIDDK NIH HHS

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Affiliation(s)

A J Matas Department of Surgery, University of Minnesota, Minneapolis, Minnesota 55455, USA.

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Sirolimus--challenging current perspectives

Sirolimus is a potent immunosuppressant drug with a novel mechanism of action. It inhibits the mammalian target of rapamycin (mTOR) and blocks the cell cycle of various cell types, including T- and B-lymphocytes. Sirolimus is widely used as a maintenance immunosuppressive agent in organ transplantation. Also, a potentially benefit of this valuable drug in some immunologic and malignant diseases is currently under scrutiny.Classical side effects: hematological (anaemia, leucopenia, thrombocytopenia), hypercholesterolemia, arthralgias, extremity oedema and impaired wound healing have been frequently associated with the use of sirolimus. Additionally with its increased use, transplant professionals are encountering a variety of previously unreported and potentially more severe side effects.Here, we review the most recent data on sirolimus unexpected side effects (with an emphasis on pulmonary and renal toxicity), its use in renal transplantation and its new potential therapeutic indications (chronic glomerulopathies, polycystic kidney disease, different types of cancer). A brief description of the current knowledge of sirolimus therapeutic drug monitoring, methods of analysis, pharmacokinetics and drug interactions with calcineurin inhibitors is also included.

Sirolimus pharmacokinetics in pediatric renal transplant recipients receiving calcineurin inhibitor co-therapy

We have previously reported sirolimus (SRL) pharmacokinetics (PK) in pediatric renal transplant recipients on a calcineurin inhibitor (CNI)-free protocol. We now report pediatric SRL PK in pediatric renal transplant patients receiving SRL + CNI. SRL was dosed to achieve target trough levels between 10 and 20 ng/mL. We performed 49 SRL PK profiles in pediatric renal transplant recipients receiving SRL in combination with either cyclosporine (CsA; 25 profiles), or tacrolimus (TCL; 24 profiles). Ten of the SRL + TCL profiles were obtained from children receiving SRL on a b.i.d. dosing regimen. All other SRL profiles were q.d. regimens. We calculated, the maximum concentration (C(max)), AUC, apparent clearance (aCL; dose/AUC) for dose in mg/m(2), and mean residence time (MRT). SRL levels were measured at 6 and 7 time points for b.i.d. and q.d. dosing, respectively. Regression analysis of SRL trough values vs. AUC showed good correlation in the SRL q.d. + CsA, SRL q.d. + TCL, and SRL b.i.d. + TCL groups (r(2) = 0.95, 0.68, and 0.44, respectively). SRL aCL corrected for body surface area was higher in children aged 0-5 yr receiving SRL with either CsA or TCL. SRL dosing schedule should be tailored to each patient. Higher SRL aCL may be present in younger children when administered with CNI.

Use of Sirolimus to Facilitate Steroid Withdrawal From a Cyclosporine Regimen

OBJECTIVE

Chronic steroid therapy has been associated with many comorbidities of transplant immunosuppression. Because sirolimus blocks one of the sites affected by steroids, we sought to examine whether substituting this drug mitigated these toxicities.

METHODS

We used intent-to-treat methodology to compare the clinical outcomes and laboratory results between 30 renal transplant recipients converted from steroids to sirolimus with a cohort of demographically matched subjects who were transplanted concurrently with the study group and maintained on steroids. All patients received ongoing cyclosporine-based immunosuppression. To compensate for pharmacokinetic interactions with sirolimus, the cyclosporine exposure was markedly reduced in the study group. Statistical comparisons utilized analysis of variance, chi-square tests, and log rank evaluation of Kaplan-Meier curves.

RESULTS

Conversion from prednisone to sirolimus was accomplished without difficulty in 27 of 30 patients. Treatment failures among the converted patients were due to chronic allograft nephropathy (n = 1), recurrence of original disease (n = 1), or chronic rejection (n = 2). By intent-to-treat analysis, the outcomes were similar in the study versus concurrent control groups. Laboratory values showed triglyceridemia as an adverse reaction to sirolimus, and reduced leukocytes, to steroid withdrawal. The observed clinical benefits solely reflected the markedly reduced cyclosporine exposure. Based on responses to a questionnaire administered prior to versus 12 and 24 months after steroid withdrawal, several domains revealed improvements in subjective complaints.

CONCLUSION

Conversion from prednisone to sirolimus in combination with cyclosporine was easily accomplished in most renal transplant recipients. Although a 2-year follow-up failed to reveal objective benefits of the maneuver (other than those consequent to reduced cyclosporine exposure), most patients reported a subjectively improved health status.