Conversion to everolimus in kidney transplant recipients: a safe and simple procedure

Calcineurin inhibitor sparing strategies in renal transplantation, part one: Late sparing strategies

Kidney transplantation improves quality of life and reduces the risk of mortality. A majority of the success of kidney transplantation is attributable to the calcineurin inhibitors (CNIs), cyclosporine and tacrolimus, and their ability to reduce acute rejection rates. However, long-term graft survival rates have not improved over time, and although controversial, evidence does suggest a role of chronic CNI toxicity in this failure to improve outcomes. Consequently, there is interest in reducing or removing CNIs from immunosuppressive regimens in an attempt to improve outcomes. Several strategies exist to spare calcineurin inhibitors, including use of agents such as mycophenolate mofetil (MMF), mycophenolate sodium (MPS), sirolimus, everolimus or belatacept to facilitate late calcineurin inhibitor withdrawal, beyond 6 mo post-transplant; or using these agents to plan early withdrawal within 6 mo; or to avoid the CNIs all together using CNI-free regimens. Although numerous reviews have been written on this topic, practice varies significantly between centers. This review organizes the data based on patient characteristics (i.e., the baseline immunosuppressive regimen) as a means to aid the practicing clinician in caring for their patients, by matching up their situation with the relevant literature. The current review, the first in a series of two, examines the potential of immunosuppressive agents to facilitate late CNI withdrawal beyond 6 mo post-transplant, and has demonstrated that the strongest evidence resides with MMF/MPS. MMF or MPS can be successfully introduced/maintained to facilitate late CNI withdrawal and improve renal function in the setting of graft deterioration, albeit with an increased risk of acute rejection and infection. Additional benefits may include improved blood pressure, lipid profile and serum glucose. Sirolimus has less data directly comparing CNI withdrawal to an active CNI-containing regimen, but modest improvement in short-term renal function is possible, with an increased risk of proteinuria, especially in the setting of baseline renal dysfunction and/or proteinuria. Renal outcomes may be improved when sirolimus is used in combination with MMF. Although data with everolimus is less robust, results appear similar to those observed with sirolimus.

Predictive factors of allosensitization in renal transplant patients switched from calcineurin to mTOR inhibitors

Conversion of kidney-transplant recipients from calcineurin inhibitors to mTOR inhibitors has been suggested to be a risk factor for increased alloimmune response. We have analyzed the development of new HLA-antibodies (HLA-Abs) early after conversion in 184 patients converted in stable phase at our hospital and compared with a control group of nonconverted comparable 63 transplants. Using single-antigen solid-phase immunoassay analysis, a preconversion and a 3-6 months postconversion sera were prospectively analyzed in every patient for the appearance of new HLA-Abs. Renal function at 2 years postconversion and cumulative graft survival were compared between groups. In 16 patients, new HLA-Abs (3-DSA and 13-NonDSA), not present at the moment of conversion, were detected (8.7% vs. 3.1% in the control group). The type of mTORi used, type of CNI preconversion, the presence of steroids, time of conversion, or indication for conversion did not have influence on this effect but the presence of HLA-Abs before conversion highly correlated with the appearance of new specificities. Patients with de novo HLA-Abs showed a trend to worst graft function and survival. In conclusion, conversion to mTORi can be followed by early appearance of de novo HLA-Abs, especially in patients with HLA-Abs preconversion, and this complication should be screened early after conversion.

Conversion to everolimus in kidney transplant recipients: to believe or not believe?

INTRODUCTION

Immunosuppression with calcineurin inhibitors (CNI) in renal transplantation is associated with chronic graft dysfunction, increased cardiovascular risk, and malignancies. Everolimus (EVR) appears to permit a CNI-sparing regimen among stable kidney recipients.

AIM

The aim of this study was to analyze the efficacy and safety of conversion from CNI to EVR.

MATERIAL AND METHODS

This was a retrospective registry-based study of all kidney transplant recipients converted from CNI to EVR between 2006 and 2010. One hundred fifty-one patients, including 69.5% males and with an overall mean age of 50.2 ± 12.7 years, underwent conversion to EVR at 37.0 ± 49.8 (16) months after transplantation with 33.7% during the first 6 months. Reasons for conversion included: CNI nephrotoxicity prevention (54.3%), chronic graft dysfunction (25.8%), malignant tumors (10.6%), CNI-adverse reactions (6.6%), and biopsy-proven CNI nephrotoxicity (2.6%). During a follow-up of 17.9 ± 9.9 months (range, 6-58.5), 18 patients (11.9%) were reconverted to CNI, 2 died with functioning grafts, and 2 lost kidney function.

RESULTS

We observed a significant (P < .001) increase in estimated glomerular filtration rate-Modification of Diet in Renal Disease (eGFR-MDRD) by 11.3% within 6 months: 56.7 ± 22.1 to 64.1 ± 23.4 mL/min/1.73 m(2). At final evaluation it was 13.7%, namely, to 65.5 ± 23.0 mL/min/1.73 m(2). At the end of follow-up the proportion of patients with >300 mg/d proteinuria increased from 7.9% to 23.3% (P = .001). Dyslipidemia prevalence increased from 69.5% to 77.5% (P = not significant [NS]) and arterial hypertension increased from 49% to 65.9% (P < .001) at the end of follow-up. Other reported side effects included oral ulcers (2.6%), edema (5.3%), interstitial pneumonitis (1.3%), and toxic hepatitis (1.3%), some of them leading to EVR discontinuation.

CONCLUSION

In our population, renal function improved significantly after conversion from CNI to EVR. Although side effects were common, most were mild, withdrawal of EVR was necessary in a low percentage of cases. EVR appears to be an effective, safe alternative to CNI for maintenance therapy in selected kidney transplant recipients.

Everolimus as primary immunosuppression in kidney transplantation: experience in conversion from calcineurin inhibitors

BACKGROUND

We analyzed our clinical experience with everolimus (EVL) and identified prognostic factors for a successful conversion.

METHODS

Retrospective study of 220 kidney recipients consecutively converted to EVL with calcineurin inhibitor elimination. We studied risk factors for proteinuria at 1 year after conversion, decline in renal function, and graft survival.

RESULTS

Baseline creatinine clearance was 52.4±17.8 mL/min vs. 53.4±20.1 mL/min 1 year after conversion (P=0.150). Median proteinuria increased from 304 mg/day (interquartile range 160-507) to 458 mg/day (interquartile range 238-892; P<0.001). Risk factors for development of proteinuria ≥900 mg/day (P75) at 1-year postconversion were creatinine clearance less than 60 mL/min (odds ratio [OR] 3.37; 95% confidence interval [CI]: 1.15-9.89), serum triglycerides ≥150 mg/day (OR 4.35; 95% CI: 1.70-11.17), no treatment with prednisone (OR 3.04; 95% CI: 1.22-7.59), baseline proteinuria ≥550 mg/day (OR 10.37; 95% CI: 3.99-26.99), and conversion ≥3 years after transplant (OR 5.77; 95% CI: 1.89-17.59). An interaction was observed between baseline proteinuria and time to conversion: in patients with baseline proteinuria ≥550 mg/day, the risk of developing proteinuria ≥900 mg/day was 77.1% if they were converted after ≥3 years posttransplant. However, this risk was 29.8% in the subgroup converted before (P=0.02). Actuarial graft survival at 1 and 4 years postconversion was 98.2% and 86.5%, respectively. Baseline proteinuria ≥550 mg/day was a risk factor for graft loss in patients converted after the third year but not in patients converted before this time. EVL discontinuation rate was 24% in the first year postconversion.

CONCLUSIONS

Conversion to EVL and elimination of calcineurin inhibitors is safe. Success depends on not making late conversions and not converting patients with high baseline proteinuria.

Conversion from sirolimus to everolimus in kidney transplant recipients receiving a calcineurin-free regimen

BACKGROUND

Everolimus (EVL) and sirolimus (SRL) were introduced into immunosuppressive regimens, in an attempt to replace or reduce the dose of the nephrotoxic calcineurin inhibitors (CNI). In our institution, due to an administrative decision, conversion from SRL to EVL, was carried out, providing us the opportunity to investigate the effectiveness and safety profile of both drugs and to review the practical conversion dose between them.

METHODS

We retrospectively analyzed the medical records of 51 maintenance kidney transplant recipients receiving an SRL-based CNI-free regimen, who were switched to EVL. SRL dose was concentration controlled to a through level of 4-8 ng/mL. Patients were converted to a variable dose of EVL that was adjusted to achieve a trough concentration of 3-8 ng/mL.

RESULTS

SRL mean dose at time of conversion was 2.0 ± 0.9 mg/d. Initial EVL mean dose was 1.3 ± 0.5 mg/d. Six months after conversion, mean EVL trough level was 6.2 ± 2.8 ng/mL. EVL dose at this point was 2.0 ± 0.9 mg/d, which was not statistically different from SRL dose at the time of conversion (p = 0.575), suggesting a conversion factor of 1:1. During this six month period post conversion, no significant changes were observed in serum creatinine, hematocrit level, platelet count, proteinuria or lipid levels. No patient experienced an acute rejection episode.

CONCLUSIONS

Conversion from SRL to EVL in renal transplant recipients receiving a CNI-free immunosuppressive regimen can be performed safely with a low trough level range of EVL. We report for the first time a conversion factor between SRL and EVL.

Conversion from a calcineurin inhibitor to everolimus therapy in maintenance liver transplant recipients: a prospective, randomized, multicenter trial

Calcineurin inhibitors (CNIs) contribute to renal dysfunction following liver transplantation. This prospective, randomized, multicenter, 6-month study (with an additional 6 months of follow-up) evaluated whether everolimus with CNI reduction or discontinuation would improve renal function in maintenance liver transplant recipients experiencing CNI-related renal impairment. Patients started everolimus therapy with CNI reduction or discontinuation (n = 72) or continued receiving standard-exposure CNI (n = 73). At month 6, 80% of the patients who had converted to everolimus had discontinued the CNI. The mean change in creatinine clearance (CrCl) from baseline to month 6 was similar between groups (everolimus, 1.0 +/- 10.2 mL/minute; controls, 2.3 +/- 7.8 mL/minute; P = 0.46), so the primary study endpoint (8 mL/minute difference in the change in CrCl) was not achieved. Among patients who continued everolimus according to the protocol, the mean increase in CrCl was 2.1 (n = 53) and 3.8 mL/minute (n = 38) at months 6 and 12, respectively, versus 2.4 (n = 68) and 3.5 mL/minute in controls (n = 51). The high frequency of CNI dose reductions in controls (77% of the patients) and the relatively long mean time post-transplant (>3 years) likely contributed to the small difference in CrCl. Biopsy-proven acute rejection occurred in 1.4% of the patients in each group, with no graft losses. Study drug discontinuation was higher in everolimus-treated patients, and adverse events were more frequent. These data demonstrate that everolimus allows for discontinuation or a major reduction of CNI exposure in liver allograft recipients suffering CNI-related renal dysfunction without a loss of efficacy. Trials targeting earlier conversion post-transplantation are required to confirm the efficacy and safety of everolimus for improving renal function after liver transplantation.

Everolimus: an update on the mechanism of action, pharmacokinetics and recent clinical trials

BACKGROUND

A growing body of evidence suggests that everolimus might offer effective immunosuppressive activity together with antiproliferative effects that may address some of the unmet needs in the long-term therapeutic management of the post-transplant patient.

OBJECTIVE

To summarize the emerging evidence for employing everolimus-based immunosuppression.

METHODS

A systematic review was conducted of the Medline, Embase and Renal Health Library (Cochrane Collaboration) databases, and of the summary publications from international transplant meetings and congresses during 2000-2008.

RESULTS

This article summarizes this analysis, with special focus on the pharmacokinetic characteristics of everolimus and on the results of its use in renal transplantation. Some data has also been included about the efficacy of the drug in other solid organ transplantation and in tumours.

CONCLUSIONS

Everolimus is an immunosuppressant drug with proven efficacy in transplantation. When used in combination with cyclosporin, better results are obtained in renal function with low cyclosporin doses. Adverse events related to this drug are frequent and lead to moderate dropout rates.

Early, abrupt conversion of de novo renal transplant patients from cyclosporine to everolimus: results of a pilot study

In a single-center study, 20 kidney transplant patients without prior rejection were abruptly converted from cyclosporine to everolimus at seven wk post-transplant. All patients received basiliximab induction with maintenance enteric-coated mycophenolate sodium and corticosteroids. Biopsy-proven acute rejection had occurred in three of 20 patients (15.0%) by the end of week seven post-conversion. All episodes were mild and reversible, with subsequent recovery of renal function. Calculated glomerular filtration rate (GFR) improved significantly (51 +/- 11 mL/min at time of conversion, 58 +/- 12 mL/min at week seven post-conversion, 57 +/- 17 mL/min at month six post-conversion; p = 0.001). No patient developed proteinuria in the nephrotic range. Twenty-two adverse events were reported in 10 patients, three of which had a suspected relationship to everolimus. Mean leukocyte and platelet count decreased significantly, and triglyceride level increased. This study suggests that kidney transplant patients without prior rejection can be converted abruptly from cyclosporine to everolimus at seven wk post-transplant, resulting in significantly improved renal function with no apparent increase, in risk of rejection and good tolerability.

Use of the New Proliferation Signal Inhibitor Everolimus in Renal Transplant Patients in Spain: Preliminary Results of the EVERODATA Registry

Everolimus (Eve) has shown good efficacy and safety profiles in clinical trials in combination with low doses of cyclosporine but there is limited experience in other modes, especially with calcineurin inhibitor elimination. We developed a retrospective study to analyze its clinical use after approval in Europe in 2005. Herein we have presented the results of a series of 272 patients followed for the first 6 months after Eve introduction. In 93.8% of cases Eve was introduced after the first month posttransplantation (conversion use), and 6 months after introduction, the CNI had been eliminated in 75% of cases. The main indication for Eve introduction was the diagnosis of a malignant neoplasm (42%), whereas the combined indication of prevention and/or treatment of toxicity, especially nephrotoxicity, accounted for 46.3% of cases. Initial doses were low (1.37 mg/d), but were progressively increased up to 2 mg/d at 6 months. Renal function remained unchanged during the follow-up period, whereas proteinuria moderately increased. Only 5 cases (2%) of acute rejection episodes were observed with excellent patient and graft survivals at 6 months after conversion. Further analysis of this extensive series of patients with a longer follow-up is needed.