Long-term outcome of very early cyclosporine minimization and de novo everolimus therapy in kidney transplant recipients: a pharmacokinetic guided approach

Pharmacokinetics of everolimus when combined with cyclosporine in Japanese de novo renal transplant recipients

BACKGROUND

Currently, there are no published data on pharmacokinetics (PK) of everolimus in combination with cyclosporine in Japanese renal transplant patients. We evaluated the PK of everolimus in Japanese de novo renal transplant patients who received everolimus in combination with cyclosporine.

METHODS

In this phase 3, multicenter, randomized, open-label study, patients were randomized (1:1) to 1 of the 2 groups: everolimus 1.5 mg (targeted C0 of 3-8 ng/mL) plus reduced-dose cyclosporine or mycophenolate mofetil 2 g/d plus standard-dose cyclosporine. PK assessments for everolimus were performed on day 28 (month 1) in the PK subpopulation.

RESULTS

A total of 11 patients (7 men), mean age 47.5 ± 11.21 years, were enrolled for PK analysis of everolimus. Starting at 1.5 mg (0.75 mg twice a day), the mean dose over a period of 28 days was 0.705 ± 0.1011 mg. Everolimus mean trough concentration was 4.307 ± 1.2459 ng/mL and mean peak concentration was 13.539 ± 3.5330 ng/mL, which peaked at 1 to 2 hours postdose. The average concentration was 7.558 ± 1.4723 ng/mL, area under the concentration-time curve was 90.70 ± 17.667 ng·h/mL, and peak-trough fluctuation was 122.6%. The PK parameters of everolimus were comparable to those in the earlier phase 3 studies (A2306 and A2307). The mean everolimus trough levels were within the target ranges at all time points ranging from 3.4 to 5.5 ng/mL (everolimus 0.75 mg twice a day, safety population). The majority of patients (>85% from day 7 onward) were maintained within the targeted everolimus trough blood levels (safety population). These data were similar to a non-Japanese study (A2309).

CONCLUSIONS

The pharmacokinetic characteristics of everolimus in Japanese de novo renal transplant patients did not differ from those previously observed in non-Japanese patients, hence the same dosage of everolimus may be acceptable in Japanese patients.

[Recent options in drug therapy after solid organ transplantation]

Solid organ transplantation has shown improvement in patient and graft survival rates due to the development of immunosuppression in the last fifty years; however only the last two decades led to the development of new, baseline immunosuppressive drugs that avoid the unlikely side effects of calcineurin inhibitors, especially nephrotoxicity. The transplanted organ is foreign to the host and, therefore, it induces a complex immune response of the recipient. In this review, a brief outline of immune response is given, followed by the introduction of new immunosuppressive drugs acting via variant pathways. These are compounds which are already in use or becoming shortly available and are potential future alternatives for the calcineurin inhibitors. This paper highlights the role of co-stimulation blockade with belatacept and the recently even more intensively studied field of tolerance induction.

Change of Cyclosporine Absorption over the Time after Kidney Transplantation

Background

Although the immunosuppressant cyclosporine (CsA) is widely used after kidney transplantation over the long term, there is still no firm consensus on the best way to monitor of CsA blood levels.

Objectives

Cyclosporine (CsA) assay is critical for the management of renal transplant recipients due to inter– and intra–patient variation in CsA absorption and metabolism. Patients and Methods: In a retrospective cross sectional study, blood levels of CsA (through and 2 hours post dose) measured at least 5 times during 3 years post transplantation, in 7702 kidney transplant recipients from different transplant center of Tehran, IR Iran between 2008 and 2012. Cyclosporine absorption (CA) calculated C2/C0 ratio.

Results

CA had a significant correlation with allograft function (P = 0.000, r =.0.285), this correlation was stronger than its relationship with C0 and C2 blood levels (P = 0.000 and P = 0.000 as well as r = 0.033 and r = 0.090, respectively). In univariate analysis during different times after transplantation, C0 and C2 blood levels significantly decreased over three years follow up (P = 0.000), (P = 0.000); While, CA reversely increases over the time (P = 0.000). In linear regression model overall CA levels had correlation with lower age of recipient (P = 0.02), hypokalemia (P = 0.001), higher level of creatinine (P = 0.02) and triglyceride (P = 0.001).

Conclusions

The present study shows that CsA absorption changes trough the post-transplant time and appears to increases over time in long–term period after kidney transplantation.

Efficacy and safety of changing from cyclosporine C0 to C2 monitoring in stable recipients following renal transplantation: a prospective cohort study

Cyclosporine doses can be adjusted individually to decrease the occurrence of rejection and nephrotoxic episodes using concentrations at 2 hours postdosing (C2). However, some transplantation centers still use trough concentrations (C0) to adjust cyclosporine doses among stable renal transplant recipients. We analyzed the efficacy and safety of changing from monitoring C0 to C2 among stable recipients following living relative donor renal transplantation. We enrolled 65 stable renal transplant recipients whose cyclosporine (Neoral) dosages were adjusted by C0, recording their cyclosporine C2 values. They were divided into low (<500 ng/mL, n=25), target (500-600 ng/mL, n=23), or high (>600 ng/mL, n=17) C2 groups. The cyclosporine dose was prospectively modified in the low and high C2 groups; all patients were followed for 12 months. We compared the incidences of complications among their transplanted kidneys and other organs. Among patients in the high C2 group, the C2 target value was achieved by reducing the cyclosporine dose by up to 575.0 mg (mean=33.8 mg/patient); 88.2% of patients showed stable levels of creatinine (Cr) and urea nitrogen (BUN) during the follow-up with decreased blood cholesterol and uric acid levels in some patients, while two subjects suffered acute rejection episodes. Among the low C2 group, the target value was achieved by increasing the cyclosporine dose by up to 755.0 mg (mean=30.2 mg/patient); during the follow-up with 84.0% of subjects displaying stable levels of Cr and BUN, four suffered increasing Cr and BUN values. Although most of stable recipients in this study benefited from C2 monitoring, some patients suffered rejection or nephrotoxicity episodes. One must be cautious to change from monitoring C0 to C2 in stable recipients following renal transplantation.