Everolimus, a derivative of sirolimus, is a potent immunosuppressant that has important anti-proliferative properties. In the present study, we demonstrated the inhibiting neointimal hyperplasia in injured carotid arteries in rats by using two different doses of everolimus administrated via the oral route for a long time.A rat model of carotid artery injury was established by balloon inflation. Eighty rats were randomly divided into the sham-operated group (n = 20), injury group (n = 20), low dosage of everolimus group (n = 20), and high dosage of everolimus group (n = 20). The low dose of everolimus (1.5 mg/kg) was given one day before injuring the carotid artery by balloon, followed by 0.75 mg/kg per day for 28 days via intragastric gavage. High dose everolimus (2.5 mg/kg) was given one day before injuring the carotid artery by balloon, followed by 1 mg/kg per day for 28 days. Expression of eukaryotic translation initiation factor 4E (eIF-4E) and phosphorylation of ribosomal protein S6 kinase 1 (P70S6K) were determined by reverse transcription-polymerase chain reaction and Western blotting analysis.In the injured carotid artery, neointimal hyperplasia was normally observed four weeks after injury. Everolimus inhibited neointimal hyperplasia after balloon injury in a dose dependent manner. At the same time, the study demonstrated that everolimus reduced the expression of P-P70S6K, eIF-4E, transforming growth factor (TGF)-β1 and of proliferating cell nuclear antigen (PCNA).Everolimus significantly inhibited neointimal hyperplasia of the injured carotid artery. The effect depended on dosage and was associated with the reduction of phosphorylation of P70S6K and the eIF-4E expression level.

Simultaneous inhibition of deregulated cancer kinome using rationally designed nanomedicine is an advanced therapeutic approach. Herein, we have developed a polymer-protein core-shell nanomedicine to inhibit critically aberrant pro-survival kinases (mTOR, MAPK and STAT5) in primitive (CD34(+)/CD38(-)) Acute Myeloid Leukemia (AML) cells. The nanomedicine consists of poly-lactide-co-glycolide core (~250 nm) loaded with mTOR inhibitor, everolimus, and albumin shell (~25 nm thick) loaded with MAPK/STAT5 inhibitor, sorafenib and the whole construct was surface conjugated with monoclonal antibody against CD33 receptor overexpressed in AML. Electron microscopy confirmed formation of core-shell nanostructure (~290 nm) and flow cytometry and confocal studies showed enhanced cellular uptake of targeted nanomedicine. Simultaneous inhibition of critical kinases causing synergistic lethality against leukemic cells, without affecting healthy blood cells, were demonstrated using immunoblotting, cytotoxicity and apoptosis assays. This cell receptor plus multi-kinase targeted core-shell nanomedicine was found better specific and tolerable compared to current clinical regime of cytarabine and daunorubicin.

Sotrastaurin, a novel selective protein-kinase-C inhibitor, inhibits early T cell activation via a calcineurin-independent pathway. Efficacy and safety of sotrastaurin in a calcineurin inhibitor-free regimen were evaluated in this two-stage Phase II study of de novo kidney transplant recipients. Stage 1 randomized 131 patients (2:1) to sotrastaurin 300 mg or cyclosporine A (CsA). Stage 2 randomized 180 patients (1:1:1) to sotrastaurin 300 or 200 mg or CsA. All patients received basiliximab, everolimus (EVR) and prednisone. Primary endpoint was composite efficacy failure rate of treated biopsy-proven acute rejection, graft loss, death or lost to follow-up. Main safety assessment was estimated glomerular filtration rate (eGFR) by MDRD-4 at Month 12. Composite efficacy failure rates at 12 months were higher in sotrastaurin arms (Stage 1: 16.5% and 10.9% for sotrastaurin 300 mg and CsA; Stage 2: 27.2%, 34.5% and 19.4% for sotrastaurin 200 mg, 300 mg and CsA). eGFR was significantly better in sotrastaurin groups versus CsA at most time points, except at 12 months. Gastrointestinal and cardiac adverse events were more frequent with sotrastaurin. Higher treatment discontinuation, deaths and graft losses occurred with sotrastaurin 300 mg. Sotrastaurin combined with EVR showed higher efficacy failure rates and some improvement in renal allograft function compared to a CsA-based therapy.

Everolimus is a potent, oral inhibitor of the mammalian target of rapamycin (mTOR) that has been investigated in multiple clinical development programs since 1996. A unique collaboration between academic and pharmaceutical experts fostered research that progressed rapidly, with simultaneous indication findings across numerous tumor types. Initially developed for the prophylaxis of organ transplant rejection, everolimus has demonstrated efficacy and safety for the treatment of patients with various types of cancer (renal cell carcinoma, neuroendocrine tumors of pancreatic origin, and breast cancer) and for adult and pediatric patients with tuberous sclerosis complex. The FDA approval of everolimus for these diseases has addressed several unmet medical needs and is widely accepted by the medical community where treatment options may be limited. An extensive clinical development program is ongoing to establish the role of everolimus as monotherapy, or in combination with other agents, in the treatment of a broad spectrum of malignancies.

BACKGROUND:

Inhibition of the mammalian target of rapamycin (mTOR) is an established treatment for multiple malignancies. We carried out an up-to-date meta-analysis to determine the risk of fatal adverse events (FAEs) in cancer patients treated with mTOR inhibitors.

PATIENTS AND METHODS:

PubMed, conferences and clinicaltrials.gov databases were searched for articles reported from January 1966 to June 2012. Eligible studies were limited to approved mTOR inhibitors (everolimus and temsirolimus) and reported on patients with cancer, randomized design and adequate safety profiles. Data extraction was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement.

RESULTS:

In all, 3193 patients from eight randomized, controlled trials (RCTs) were included, 2236 from everolimus trials and 957 from temsirolimus trials. The relative risk (RR) of FAEs related to mTOR inhibitors use was 2.20 (95% CI, 1.25-3.90; P = 0.006) compared with control patients. On subgroup analysis, no difference in the rate of FAEs was found between everolimus and temsirolimus or between tumor types [renal cell carcinoma (RCC) versus non-RCC]. No evidence of publication bias was observed.

CONCLUSION:

The use of mTOR inhibitors is associated with a small but higher risk of FAEs compared to control patients. In the appropriate clinical scenario, the use of these drugs remains justified in their approved indications.

Bronchial carcinoids (BC) are rare neuroendocrine tumors that are still orphan of medical treatment. Human BC primary cultures may display resistance to Everolimus, an inhibitor of the mammalian target of rapamycin (mTOR), in terms of cell viability reduction. Our aim is to assess whether the novel dual PI3K/mTOR inhibitor, NVP-BEZ235, may be effective in Everolimus-resistant human BC tissues and cell lines. In addition, we search for possible markers of mTOR inhibitors efficacy, that may help in identifying the patients that may benefit from mTOR inhibitors treatment, sparing them from ineffective therapy. We found that NVP-BEZ235 is twice as potent as Everolimus in reducing cell viability and activating apoptosis in human BC tissues that display sensitivity to mTOR inhibitors, but is not effective in Everolimus-resistant BC tissues and cell lines, that by-pass cyclin D1 down-regulation and escape G0/G1 blockade. Rebound AKT activation was not observed in response to treatment with either mTOR inhibitor in 'resistant' BC cells. In addition to total mTOR levels, putative markers of BC sensitivity to mTOR inhibitors are represented by AKT, p70S6K and ERK1/2 protein levels. Finally, we validated these markers in an independent BC group. These data indicate that the dual PI3K/mTOR inhibitor NVP-BEZ235 is more potent than Everolimus in reducing human BC cell proliferation. 'Resistant' cells display lower levels of mTOR, p70S6K, AKT and ERK1/2, indicating that these proteins may be useful as predictive markers of resistance to mTOR and PI3K/mTOR inhibitors in human BC.

Bronchiolitis obliterans (BO) is a complication after allogeneic hematopoietic stem cell transplantation (HSCT). BO-management comprises intensive immunosuppression, but treatment response is poor. We investigated the effect of cyclosporine A (CsA), tacrolimus (FK506), methylprednisolone (mPRED), mycophenolate mofetil (MMF), and everolimus on the proliferation of primary lung myofibroblasts from HSCT-patients with bronchiolitis obliterans syndrome (BOS).

Methods:

Cells were isolated from surgical lung biopsies of 8 HSCT-patients with BOS. Proliferation was assessed by [(3)H]-thymidine-incorporation.

Results:

Biopsies revealed constrictive BO in 3 and lymphocytic bronchiolitis (LB) in 5 patients. CsA and FK506 significantly induced proliferation of myofibroblasts. mPRED and MMF caused a significant inhibition of proliferation, whereas everolimus had no effect. Co-stimulation with FK506, mPRED and MMF significantly inhibited proliferation. Serial pulmonary function tests over 12 months after lung biopsy and under the triple-therapy demonstrated that patients with LB had a significant improvement of their FEV1, whereas FEV1 of patients with BO was unchanged.

Conclusion:

Our data demonstrate a pro-poliferative effect of calcineurin inhibitors on primary human lung myofibroblasts obtained from patients with BOS after HSCT. In contrast, based on the observed anti-proliferative capacity of MMF in vitro, MMF-based calcineurin inhibitor-free treatment strategies should be further evaluated in patients with BO after HSCT.

The efficacy of everolimus with reduced cyclosporine in de novo heart transplant patients has been demonstrated convincingly in randomized studies. Moreover, everolimus-based immunosuppression in de novo heart transplant recipients has been shown in two randomized trials to reduce the increase in maximal intimal thickness based on intravascular ultrasound, indicating attenuation of cardiac allograft vasculopathy (CAV). Randomized trials of everolimus in de novo heart transplantation have also consistently shown reduced cytomegalovirus infection versus antimetabolite therapy. In maintenance heart transplantation, conversion from calcineurin inhibitors to everolimus has demonstrated a sustained improvement in renal function. In de novo patients, a renal benefit may only be achieved if there is an adequate reduction in exposure to calcineurin inhibitor therapy. Delayed introduction of everolimus may be appropriate in patients at high risk of wound healing complications, e.g. diabetic patients or patients with ventricular assist device. The current evidence base suggests that the most convincing reasons for use of everolimus from the time of heart transplantation are to slow the progression of CAV and to lower the risk of cytomegalovirus infection. A regimen of everolimus with reduced-exposure calcineurin inhibitor and steroids in de novo heart transplant patients represents a welcome addition to the therapeutic armamentarium.

OBJECTIVE:

We report the clinical features and management outcomes in 7 patients with everolimus-related stomatitis.

STUDY DESIGN:

Fifteen women with hormone-receptor-positive advanced breast cancer receiving everolimus combined with exemestane were prospectively evaluated to assess the development of stomatitis. Oral ulcers were diagnosed based on established criteria.

RESULTS:

Seven patients developed stomatitis (46.6%). All patients were treated with topical dexamethasone solution, while everolimus was temporarily discontinued in 4 patients. Stomatitis resolved within 1-2 weeks. Two of the 4 patients, who had interrupted everolimus, developed recurrent stomatitis following drug resume and everolimus was again discontinued and restarted after 2 weeks. To date, 5 patients receive everolimus in full dose. The 2 patients, who developed recurrent stomatitis, received a reduced dose.

CONCLUSIONS:

Everolimus-related oral ulcers were frequent and led to dose modifications. Controlled trials, endorsing a consensus in terminology, are needed to evaluate measures on prevention and management of this unique toxicity.