Three-yr safety and efficacy of everolimus and low-dose cyclosporine in de novo pediatric kidney transplant patients

Subclinical Rejection and Immunosuppression in Pediatric Kidney Transplant Recipients : Single Centre Study

Background: By the time of histological confirmation of rejection is achieved, renal scarring may for treatment as a realistic option . This study aims to study the subclinical pathological graft data and to evaluate the histopathological impact of different immunosuppression protocols in pediatric renal transplant recipients. Methods: This is a case series that included twenty living donor renal transplant recipients. All included cases received the classic triple immunotherapy for at least one month post-transplantation [Steroids, calconurine inhibitors (CNI), and mycofenlolic mofetile (MMF)]. Based on their immunological risk stratification; included cases were divided into 2 groups: group (A) continued on CNI based triple therapy protocol; group (B) shifted to evirolimus /low dose CNI protocol. Surveillance biopsies were done for all cases at one and four month post-transplantation. Results: One and four month biopsies revealed subclinical rejection (including borderline changes) in 4 (20%) cases and 6 (30%) cases respectively. The number of patients received tacrolimus/MMF therapy significantly increased (p=0.02) while that of patients on everloimus/low dose CNI significantly decreased (p=0.014) due to drug modifications based on four month surveillance biopsy data. Conclusion: Subclinical rejection is not uncommon in pediatric renal graft recipients which makes surveillance biopsy might be of help. Early usage of evirolimus/low CNI protocol is associated with higher rejection rate than triple therapy.

Considerations and controversies of pharmacologic management of the pediatric kidney transplant recipient

Pediatric kidney transplantation has experienced considerable growth and improvement in patient and allograft outcomes over the past 20 years, in part due to advancements in immunosuppressive regimens and management. Despite this progress, care for this unique population can be challenging due to limited pediatric transplant data and trials, intricacies related to differences in children and adolescents compared with their adult counterparts, and limitations to long-term survival facing all solid organ transplant populations. Immunosuppression and infection prevention practices vary from one pediatric transplant center to another and clinical controversies exist surrounding treatment and dosing. This review aims to summarize key aspects of pharmacologic management in this population and present pertinent data that describe the influence of practice to serve as a resource for practitioners caring for this unique specialty patient population. Additionally, this review highlights select controversies that exist within pediatric kidney transplantation.

Skin cancer in children after organ transplantation

Skin cancer is the second most common complication of organ transplantation in children. The frequency of skin cancer incidence after organ transplantation is different in paediatric and adult populations. The post-transplant lymphoproliferative disease is the most common group of malignancies after organ transplantation in paediatric population. The majority of researchers who examined children with kidney, liver, heart or lungs grafts observed that the risk of skin cancer was three times higher than in the general population whereas in adults even200 times higher. The occurrence of skin cancer in children after transplantation is extremely rare during childhood. The risk increases in early adulthood. Malignancies occurring after solid organ transplantation result from many different factors. These include the immunological condition of the child, dose and time of immunosuppression, and oncogenic viruses. The increased risk of skin cancer following paediatric transplantation requires prevention and adequate education of children and their parents. These involve avoiding sun exposure and protection such as sunscreens and protective clothing. The early detection of cancer in transplant recipients is very important. Prevention of cancer includes regular dermatological examination.

Early conversion of pediatric kidney transplant patients to everolimus with reduced tacrolimus and steroid elimination: Results of a randomized trial

In a 12-month, multicenter, open-label study, 106 children were randomized at 4 to 6 weeks after kidney transplantation to switch to everolimus with reduced TAC (EVR/rTAC) and steroid elimination from month 5 posttransplant or to continue standard tacrolimus with mycophenolate mofetil (sTAC/MMF) and steroids. The cumulative incidence of a co-primary efficacy end point (biopsy-proven acute rejection [BPAR], graft loss, or death from randomization to month 12) was 10.3% with EVR/rTAC and 5.8% with sTAC/MMF (difference 4.4%; P = .417). BPAR occurred in 9.6% and 5.6% of patients, respectively. Patient and renal allograft survival were 100%. The co-primary end point of mean estimated glomerular filtration rate at month 12 was 76.2 mL/min/1.73 m² with EVR/rTAC and 72.5 mL/min/1.73 m² for sTAC/MMF (difference 3.8 mL/min/1.73m² ; P = .49). One EVR/rTAC patient developed posttransplant lymphoproliferative disease. Longitudinal growth and sexual maturation were equivalent between groups. The randomized drug regimen was discontinued in 34.6% and 13% of patients in the EVR/rTAC and sTAC/MMF groups, respectively (P = .024), and discontinued due to adverse events/infections in 25.0% and 11.1% of patients (P = .062). In conclusion, early conversion of pediatric kidney transplant patients from TAC, MMF, and steroids to EVR/rTAC and steroid withdrawal maintains immunosuppressive efficacy and preserves renal function.

A pharmacological rationale for improved everolimus dosing in oncology and transplant patients

AIMS

Everolimus is a drug from the class of mammalian target of rapamycin inhibitors used for both immunosuppressant and oncological indications. We postulate that there is room for improvement of dosing, as the optimal immunosuppressive dose in calcineurin-free regimens is unknown and since the once daily dosing regimen for oncological indications is often associated with treatment-limiting toxicity.

METHODS

We developed a mechanistic population pharmacokinetic model for everolimus in cancer and transplant patients and explored alternative dosing regimens.

RESULTS

We found that formulation did not influence bioavailability and that use of >20 mg prednisolone daily increased everolimus clearance. In transplant patients, the approved dose of 0.75-1 mg twice daily (BID) results in subtherapeutic trough levels (<6 μg l-1 ) and that a higher starting dose of 2.25-3 mg BID is required.

CONCLUSION

For oncological indications, our results encourage the investigation of dosing everolimus 3.75 mg BID in terms of superiority in safety and noninferiority in efficacy.

Everolimus-associated perianal ulcers in an eight-month-old heart transplant recipient

mTOR inhibitors have a wide spectrum of therapeutic applications in adults and children. Little is known, however, about serious adverse effects in children undergoing mTOR inhibitor therapy. Oral ulcers are common and sometimes severe, but no other gastrointestinal involvement has been reported so far. Here we present a case of everolimus-associated perianal ulcers in an eight-month-old infant, 3 months after heart transplantation, which necessitated the drug's discontinuation. In a thorough series of diagnostic tests, we identified no other cause for the progressive perianal ulceration. The recognition and appropriate management of mTOR inhibitors' adverse effects in pediatric patients are essential and remain challenging.

Treatment of renal angiomyolipoma in tuberous sclerosis complex (TSC) patients

In adult tuberous sclerosis complex (TSC) patients, renal complications are the leading cause of death. Beginning in childhood, up to 80 % of patients develop renal angiomyolipoma characterized by a size-dependent risk of life-threatening bleeding. After discovery of the two causative genes, TSC1 and TSC2, and the role of mammalian target of rapamycin (mTOR) regulation in the pathogenesis of TSC, an increasing number of clinical studies evaluating mTOR inhibition in TSC patients have shown impressive results in many organ manifestations, such as brain, lung, and kidney. For renal angiomyolipoma, mTOR inhibitor treatment fundamentally changed the approach from preventive embolization or even partial nephrectomy to everolimus treatment in order to preserve kidney function.

Therapeutic Drug Monitoring of Everolimus: A Consensus Report

In 2014, the Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology called a meeting of international experts to provide recommendations to guide therapeutic drug monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice. EVR is a potent inhibitor of the mammalian target of rapamycin, approved for the prevention of organ transplant rejection and for the treatment of various types of cancer and tuberous sclerosis complex. EVR fulfills the prerequisites for TDM, having a narrow therapeutic range, high interindividual pharmacokinetic variability, and established drug exposure-response relationships. EVR trough concentrations (C0) demonstrate a good relationship with overall exposure, providing a simple and reliable index for TDM. Whole-blood samples should be used for measurement of EVR C0, and sampling times should be standardized to occur within 1 hour before the next dose, which should be taken at the same time everyday and preferably without food. In transplantation settings, EVR should be generally targeted to a C0 of 3-8 ng/mL when used in combination with other immunosuppressive drugs (calcineurin inhibitors and glucocorticoids); in calcineurin inhibitor-free regimens, the EVR target C0 range should be 6-10 ng/mL. Further studies are required to determine the clinical utility of TDM in nontransplantation settings. The choice of analytical method and differences between methods should be carefully considered when determining EVR concentrations, and when comparing and interpreting clinical trial outcomes. At present, a fully validated liquid chromatography tandem mass spectrometry assay is the preferred method for determination of EVR C0, with a lower limit of quantification close to 1 ng/mL. Use of certified commercially available whole-blood calibrators to avoid calibration bias and participation in external proficiency-testing programs to allow continuous cross-validation and proof of analytical quality are highly recommended. Development of alternative assays to facilitate on-site measurement of EVR C0 is encouraged.

mTOR Inhibitors for the Treatment of Severe Congenital Hyperinsulinism: Perspectives on Limited Therapeutic Success

CONTEXT

Congenital hyperinsulinism (CHI) is the most common cause of persistent hypoglycemia in neonates and infants. In medically unresponsive CHI, subtotal pancreatectomy is performed to achieve euglycemia with consequent diabetes in later life. Sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, has been reported to obviate the need for pancreatectomy, but experience is limited.

OBJECTIVE

We have investigated the efficacy and adverse effect profile of mTOR inhibitors in the treatment of severe CHI.

DESIGN, SETTING, AND PATIENTS

This was an observational review of 10 severe CHI patients treated with mTOR inhibitors, in France and the United Kingdom, with the intention of achieving glycemic control without pancreatectomy. Safety information was recorded.

MAIN OUTCOME MEASURE(S)

We examined whether mTOR inhibitors achieved glycemic control, fasting tolerance, and weaning of supportive medical therapy.

RESULTS

mTOR inhibition achieved euglycemia, fasting tolerance, and reduced medical therapy in only three patients (30%). Triglyceride levels were elevated in five patients (50%). One child required a blood transfusion for anemia, four had stomatitis, two had sepsis, one developed varicella zoster, and two patients developed gut dysmotility in association with exocrine pancreatic insufficiency. In silico analysis of transcriptome arrays from CHI patients revealed no significant association between mTOR signaling and disease. Pancreatic tissue from two patients who did not respond to sirolimus showed no reduction in cell proliferation, further suggesting that mTOR signaling did not down-regulate proliferation in the CHI pancreas.

CONCLUSION

mTOR inhibitor treatment is associated with very limited success and must be used with caution in children with severe CHI.

Safety of Everolimus in Patients Younger than 3 Years of Age: Results from EXIST-1, a Randomized, Controlled Clinical Trial

OBJECTIVES

To assess the long-term safety of everolimus in young children with tuberous sclerosis complex (TSC)-associated subependymal giant cell astrocytoma (SEGA).

STUDY DESIGN

EXamining everolimus In a Study of Tuberous Sclerosis Complex-1 (EXIST-1) was a multicenter, randomized, double-blind phase 3 study with an open-label extension evaluating the efficacy and tolerability of everolimus in patients with TSC-associated SEGA. Everolimus was initiated at 4.5 mg/m(2)/day and titrated to blood trough levels of 5-15 ng/mL. Post hoc analysis of safety data (adverse events [AEs]) was performed in a subgroup of patients aged <3 years at everolimus initiation.

RESULTS

Eighteen patients (median age 1.82 years) were included; 16 were still receiving everolimus at the analysis cut-off date of January 11, 2013. Median everolimus exposure was 31.1 months (range, 11.5-39 months). One patient discontinued treatment because of AEs (ie, Acinetobacter bacteremia, increased blood alkaline phosphatase, and viral infection). AEs were reported in all patients, but events were mostly grade 1/2 in severity; 12 patients (66.7%) experienced grade 3 events, and 2 patients (11.1%) reported grade 4 events. The most common AEs were stomatitis, cough, pharyngitis, and pyrexia; no new safety issues were identified in this population. Serious AEs were reported in 50% of patients; these were suspected to be medication related in 4 patients (22.2%).

CONCLUSIONS

Everolimus appears to be a safe therapeutic option for patients aged <3 years with TSC-associated SEGA. The small sample size in this subpopulation limits interpretation of the results; additional studies in the pediatric population are needed and are underway.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT00789828.

Everolimus in de novo liver transplant recipients: a systematic review

BACKGROUND

Everolimus has no nephrotoxicity and is used to treat patients with post-liver transplant chronic renal insufficiency. The present systematic review was to evaluate the efficacy and safety of everolimus in de novo liver transplant patients.

DATA SOURCES

Randomized controlled trials comparing everolimus for de novo liver transplant in PubMed, the Cochrane Library, and ScienceDirect published up to March 31, 2014 were searched by two independent reviewers. Mean differences and 95% confidence interval (95% CI) for renal function, relative risk (RR) and 95% CI for treated biopsy-proven acute rejection (tBPAR), graft loss, death, neoplasms/tumor recurrence, and adverse events were collected. Meta-analyses were performed with RevMan version 5.10.

RESULTS

A total of four randomized controlled trials covering 1119 cases were included. The meta-analyses revealed that compared with standard exposure of calcineurin inhibitors (CNIs), everolimus combined with reduced CNIs improved creatinine clearance (calculated with the Cockcroft-Gault formula) by 5.13 mL/min at one year (95% CI: 0.42-9.84; P=0.03), and decreased tBPAR (RR: 0.56; 95% CI: 0.35-0.90; P=0.02). Everolimus initiation with CNIs elimination improved glomerular filtration rate (GFR, measured with the modification of diet in renal disease formula) of 10.42 mL/min/1.73 m2 (95% CI: 3.44-17.41; P<0.01) one year after treatment, but increased tBPAR (RR: 1.71; 95% CI: 1.15-2.53; P<0.01). Everolimus decreased the risk of neoplasms/tumor recurrence after liver transplant (RR: 0.60; 95% CI: 0.34-1.03; P=0.06), but was associated with greater risk of adverse events which resulted in drug discontinuation (RR: 1.98; 95% CI: 1.49-2.64; P<0.01).

CONCLUSIONS

Early introduction of everolimus combined with low-dose or no CNI in de novo liver transplant significantly improves renal function one year post treatment. Everolimus combined with low-dose CNI decreases the risk of tBPAR one year after liver transplant, but everolimus administered without CNIs increases tBPAR.

Efficacy and Safety of an Everolimus- vs. a Mycophenolate Mofetil-Based Regimen in Pediatric Renal Transplant Recipients

Introduction

Data on the efficacy and safety of everolimus in pediatric renal transplantation compared to other immunosuppressive regimens are scarce.

Patients/Methods

We therefore performed a multicenter, observational, matched cohort study over 4 years post-transplant in 35 patients on everolimus plus low-dose cyclosporine, who were matched (1:2) with a control group of 70 children receiving a standard-dose calcineurin-inhibitor- and mycophenolate mofetil-based regimen.

Results

Corticosteroids were withdrawn in 83% in the everolimus vs. 39% in the control group (p<0.001). Patient and graft survival were comparable. The rate of biopsy-proven acute rejection episodes Banff score ≥ IA during the first year post-transplant was 6% in the everolimus vs. 13% in the control group (p = 0.23). The rate of de novo donor-specific HLA antibodies (11% in everolimus, 18% in controls) was comparable (p = 0.55). At 4 years post-transplant, mean eGFR in the everolimus group was 56±33 ml/min per 1.73 m² vs. 63±22 ml/min per 1.73 m² in the control group (p = 0.14). Everolimus therapy was associated with less BK polyomavirus replication (3% vs. 17% in controls; p = 0.04), but with a higher percentage of arterial hypertension and more hyperlipidemia (p<0.001).

Conclusion

In pediatric renal transplantation, an everolimus-based regimen with low-dose cyclosporine yields comparable four year results as a standard regimen, but with a different side effect profile.