A phase I study of a 4-week course of SDZ-RAD (RAD) quiescent cyclosporine-prednisone-treated renal transplant recipients

Everolimus Personalized Therapy: Second Consensus Report by the International Association of Therapeutic Drug Monitoring and Clinical Toxicology

ABSTRACT

The Immunosuppressive Drugs Scientific Committee of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology established the second consensus report to guide Therapeutic Drug Monitoring (TDM) of everolimus (EVR) and its optimal use in clinical practice 7 years after the first version was published in 2016. This version provides information focused on new developments that have arisen in the last 7 years. For the general aspects of the pharmacology and TDM of EVR that have retained their relevance, readers can refer to the 2016 document. This edition includes new evidence from the literature, focusing on the topics updated during the last 7 years, including indirect pharmacological effects of EVR on the mammalian target of rapamycin complex 2 with the major mechanism of direct inhibition of the mammalian target of rapamycin complex 1. In addition, various concepts and technical options to monitor EVR concentrations, improve analytical performance, and increase the number of options available for immunochemical analytical methods have been included. Only limited new pharmacogenetic information regarding EVR has emerged; however, pharmacometrics and model-informed precision dosing have been constructed using physiological parameters as covariates, including pharmacogenetic information. In clinical settings, EVR is combined with a decreased dose of calcineurin inhibitors, such as tacrolimus and cyclosporine, instead of mycophenolic acid. The literature and recommendations for specific organ transplantations, such as that of the kidneys, liver, heart, and lungs, as well as for oncology and pediatrics have been updated. EVR TDM for pancreatic and islet transplantation has been added to this edition. The pharmacodynamic monitoring of EVR in organ transplantation has also been updated. These updates and additions, along with the previous version of this consensus document, will be helpful to clinicians and researchers treating patients receiving EVR.

Pneumocystis jirovecii pneumonia in solid organ transplant recipients: a descriptive analysis for the Swiss Transplant Cohort

BACKGROUND

Descriptive data on Pneumocystis jirovecii pneumonia (PJP) in solid organ transplant recipients (SOTr) in the era of routine Pneumocystis-prophylaxis are lacking.

METHODS

All adult SOTr between 2008 and 2016 were included. PJP was diagnosed based on consensus guidelines. Early-onset PJP was defined as PJP within the first-year-post-transplant.

RESULTS

41/2842 SOTr (1.4%) developed PJP (incidence rate: 0.01/1000 person-days) at a mean of 493-days post-transplant: 21 (51.2%) early vs 20 (48.8%) late-onset PJP. 2465 (86.7%) SOTr received Pneumocystis-prophylaxis for a mean 316 days. PJP incidence was 0.001% and 0.003% (log-rank < 0.001) in SOTr with and without Pneumocystis-prophylaxis, respectively. PJP was an early event in 10/12 (83.3%) SOTr who did not receive Pneumocystis-prophylaxis and developed PJP, compared to those patients who received prophylaxis (11/29, 37.9%; P-value: 0.008). Among late-onset PJP patients, most cases (13/20, 65%) were observed during the 2nd year post-transplant. Age ≥65 years (OR: 2.4, P-value: 0.03) and CMV infection during the first 6 months post-SOT (OR: 2.5, P-value: 0.006) were significant PJP predictors, while Pneumocystis-prophylaxis was protective for PJP (OR: 0.3, P-value: 0.006) in the overall population. Most patients (35, 85.4%) were treated with trimethoprim-sulfamethoxazole for a mean 20.6 days. 1-year mortality was 14.6%.

CONCLUSIONS

In the Pneumocystis-prophylaxis-era, PJP remains a rare post-transplant complication. Most cases occurred post-PJP-prophylaxis-discontinuation, particularly during the second-year-post-transplant. Additional research may help identify indications for Pneumocystis-prophylaxis prolongation.

Adequacy of Initial Everolimus Dose, With and Without Calcineurin Inhibitors, in Kidney Transplant Recipients

BACKGROUND

This study investigates the adequacy of initial everolimus (EVR) dose, with and without calcineurin inhibitors (CNI), in kidney transplant recipients.

METHODS

This retrospective cohort analysis involved data from 305 kidney transplant recipients participating in 3 randomized trials receiving reduced dose cyclosporin A (CsA) combined with EVR 0.75 mg BID (CSA/EVR0.75, N = 32) or 1.5 mg BID (CSA/EVR1.5, N = 31), reduced dose tacrolimus (TAC) combined with EVR 1.5 mg BID (TAC0.05/EVR1.5, N = 83), standard dose TAC combined with EVR 1.5 mg BID (TAC0.1/EVR1.5, N = 93), and EVR 1.5 mg BID (EVR1.5, N = 66) with TAC introduction after day 5. The adequacy of the initial EVR dose, based on EVR whole blood trough between 3 and 8 ng/mL, was compared using first EVR blood concentrations obtained at day 3 after transplantation.

RESULTS

Recipient age, proportion of patients with diabetes mellitus, and proportion of grafts from living donors were different among the groups. Dose-corrected EVR concentrations were higher in patients receiving CsA than in those receiving TAC or no calcineurin inhibitors (6.7 ± 5.9 versus 5.4 ± 2.2 versus 2.4 ± 0.8 versus 2.5 ± 0.9 versus 2.2 ± 0.7, P = 0.000). No differences were observed comparing dose adjusted EVR concentrations combined with TAC or alone (P = 0.073). The proportion of patients with EVR concentration below <3 ng/mL was lower when EVR was combined with CsA (25 versus 3 versus 43 versus 33 versus 50%, P = 0.000). Later introduction of TAC did not influence EVR concentrations. There were no differences in mean CsA concentrations comparing patients receiving EVR 0.75 or 1.5 mg BID (240 ± 143 versus 213 ± 105 ng/mL). On the other hand, mean TAC concentrations were higher according to the initial TAC dose regimen (6.4 ± 3.9 versus 9.8 ± 5.9 ng/mL).

CONCLUSIONS

In de novo kidney transplant recipients, the choice of the initial dose of EVR should consider the type of calcineurin inhibitor to reach target EVR concentration within the first week in a higher proportion of patients, maximizing the efficacy/toxicity profile.

Everolimus in the treatment of neuroendocrine tumors of the respiratory and gastroenteropancreatic systems

Neuroendocrine tumors (NETs) are a rare diverse group of malignancies occurring most commonly in the gastroenteropancreatic system and the lungs. The incidence of NETs is increasing worldwide; median survival for patients with metastatic NETs is 5–65 months. A growing body of evidence shows survival benefit in patients with advanced NETs (gastroenteropancreatic and lung) treated with mTOR inhibitor everolimus, with improvement in survival being demonstrated in the clinical trial and real-world setting. Everolimus has been shown to have a manageable safety profile, with the most common adverse events being stomatitis, rash, diarrhea, fatigue and infections. Due to the rarity of the condition, there are challenges in conducting clinical trials in these patients. Further research is required to clarify the role of adjuvant therapy, treatment sequencing and the use of multimodality treatments.

Future Immunosuppressive Agents in Solid-Organ Transplantation

Objective

To review the pharmacology, pharmacokinetics, efficacy, and safety of mycophenolate sodium, everolimus, and FTY720.

Study Selection and Data Extraction

Clinical trials and abstracts evaluating mycophenolate sodium, everolimus, and FTY720 in solid-organ transplantation were considered for evaluation. English-language studies and published abstracts were selected for inclusion.

Data Synthesis

Mycophenolate sodium has recently been approved by the Food and Drug Adminstration for marketing in the United States; everolimus and FTY720 are immunosuppressive agents that may soon be available in the United States. These agents have proven efficacy in reducing the incidence of acute rejection in solid-organ transplantation. Clinical trials have shown that these newer agents are relatively well tolerated. The most common adverse events associated with these agents were gastrointestinal and hematologic effects (mycophenolate sodium); hyperlipidemia, increased serum creatinine, and hematologic effects (everolimus); and gastrointestinal effects, headache, and bradycardia (FTY720).

Conclusion

Mycophenolate sodium has been approved in some European countries and the United States. Everolimus has been approved in some European countries and a new drug application has been submitted to the Food and Drug Administration. FTY720 is currently in phase III clinical trials and submission to the Food and Drug Administration for approval is a few years away. The approval of these agents will furnish the transplant practitioner with even more options for immunosuppression.

Bioresorbable drug-eluting scaffolds for treatment of vascular disease

INTRODUCTION

Theoretical advantages of fully bioresorbable scaffold (BRS) stem from transient vessel support without rigid caging. Therefore, it could reduce long-term adverse events associated with the presence of foreign materials.

AREAS COVERED

This article will provide an overview of: drug-eluting BRS for various applications in the treatment of vascular disease; The mechanisms of active agent release from such scaffolds; currently available drug-eluting BRS and their future applications are also discussed.

EXPERT OPINION

The current BRS have been developed in order to achieve optimal vascular patency while providing long-term safety. The clinical efficacy and safety of BRS in coronary treatment have been reported as equal to that of the current metallic drug eluting stents in simple lesions. The application of BRS can potentially be expanded to other vascular beds. The research in bioengineering for the appropriate materials should not only focus on biocompatibility but also should be tailored according to the sites of implantation, which may require different strength and supporting period. The ultimate goal in this field is to develop a biocompatible device that provides equivalent and complementary therapy to other devices, and is able to disappear when the mechanical support and drug delivery are no longer required.

Long-term clinical outcomes of everolimus-eluting stent versus paclitaxel-eluting stent in patients undergoing percutaneous coronary interventions: a meta-analysis

BACKGROUND

Everolimus -eluting stent (EES) is common used in patients undergoing percutaneous coronary interventions (PCI). Our purpose is to evaluate long-term clinical outcomes of everolimus -eluting stent (EES) versus paclitaxel-eluting stent (PES) in patients undergoing percutaneous coronaryinterventions (PCI) in randomized controlled trials (RCTs).

METHODS

We searched Medline, EMBASE, Cochrane Library, CNKI, VIP and relevant websites ( https://scholar-google-com.ezproxy.lib.usf.edu/ ) for articles to compare outcomes between everolimus-eluting stent and paclitaxel-eluting stent without language or date restriction. RCTs that compared the use of everolimus -eluting stent and paclitaxel-eluting stent in PCI were included. Variables relating to patient, study characteristics, and clinical endpoints were extracted. Meta-analysis was performed using RevMan 5.2 software.

RESULTS

We identified 6 published studies (from three randomized trials) more on everolimus-eluting stent (n = 3352) than paclitaxel-eluting (n = 1639), with follow-up duration ranging from 3, 4 and 5 years. Three-year outcomes of everolimus-eluting stent compared to paclitaxel-eluting were as following: the everolimus-eluting stent significantly reduced all-cause death (relative risk [RR]:0.63; 95% confidence interval [CI]: 0.46. to 0.82), MACE (RR: 0.56; 95% CI: 0.41 to 0.77), MI (RR: 0.64; 95% CI: 0.48 to 0.86), TLR (RR: 0.72; 95% CI: 0.59 to 0.88), ID-TLR (RR: 0.74; 95% CI: 0.59 to 0.92) and ST (RR: 0.54; 95% CI: 0.32 to 0.90). There was no difference in TVR between the everolimus-eluting and paclitaxel-eluting (RR: 0.76; 95% CI: 0.58 to 1.10); Four-year outcomes of everolimus-eluting compared to paclitaxel-eluting: the everolimus-eluting significantly reduced MACE (RR: 0.44; 95% CI: 0.18 to 0.98) and ID-TLR (RR: 0.47; 95 % CI: 0.23 to 0.97). There was no difference in MI (RR: 0.48; 95% CI: 0.16 to 1.46), TLR (RR: 0.46; 95% CI: 0.20 to 1.04) and ST ((RR: 0.34; 95% CI: 0.05 to 2.39). Five-year outcomes of everolimus-eluting stent compared to paclitaxel-eluting: There was no difference in ID-TLR (RR: 0.67; 95% CI: 0.45 to 1.02) and ST (RR: 0.71; 95% CI: 0.28 to 1.80).

CONCLUSIONS

In the present meta-analysis, everolimus-eluting appeared to be safe and clinically effective in patients undergoing PCI in comparison to PES in 3-year clinical outcomes; there was similar no difference in reduction of ST between EES and PES in long-term(≥ 4 years) clinical follow-ups. Everolimus-eluting is more safety than paclitaxel-eluting in long-term clinical follow-ups, whether these effects can be applied to different patient subgroups warrants further investigation.

A randomized trial of everolimus and low-dose cyclosporine in renal transplantation: with or without steroids?

This multicenter, randomized, prospective, controlled trial (EVIDENCE study) aimed to determine short-term effects of early steroid withdrawal in renal transplant patients initially treated with everolimus, low-dose cyclosporine (CsA), and steroids. Patients were randomized to standard triple therapy with CsA, everolimus twice daily and steroids (group A), steroid-free immunosuppression (group B), or triple therapy once daily (group C). However, since patient enrollment was slower than expected, group C randomization was prematurely discontinued. The primary end point was treatment failure rate (composite end point of death, graft loss, biopsy-proven acute rejection, and loss to follow-up) between randomization and month 12. Patients evaluable for the primary end point included 139 randomized patients. According to intention-to-treat analysis, 2.8% of patients in group A and 14.7% in group B experienced treatment failure (95% upper confidence limit 19.7%). As this was higher than the predefined noninferiority limit of 10%, noninferiority could not be proved. No conclusive statements can be made on noninferiority of the steroid withdrawal regimen vs the standard regimen in these patients. Additional studies with longer follow-up are required to determine the efficacy of steroid-free immunosuppression in renal transplant recipients receiving everolimus.

Everolimus-eluting stent platforms in percutaneous coronary intervention: comparative effectiveness and outcomes

Despite the remarkable benefits obtained following the introduction of the first-generation drug-eluting stent (DES), concerns were raised over its long-term safety, particularly with regard to very late (beyond 1 year) stent thrombosis. Newer-generation DESs have been developed to overcome this limitation using novel stent platforms, new drugs, more biocompatible durable polymers, and bioabsorbable polymers or backbones. To date, new-generation DESs have virtually replaced the use of first-generation DESs worldwide. In this review article, we discuss in detail the design, pharmacology, and mechanism of action of the newer-generation permanent and bioresorbable everolimus-eluting platforms. Furthermore, we present and evaluate the current evidence on the performance and safety of these devices compared to those of other available stent platforms.

Neurological complications after liver transplantation as a consequence of immunosuppression: univariate and multivariate analysis of risk factors

Neurological complications (NCs) can frequently and significantly affect morbidity and mortality of liver transplant (LT) recipients. We analysed incidence, risk factors, outcome and impact of the immunosuppressive therapy on NC development after LT. We analysed 478 LT in 440 patients, and 93 (19.5%) were followed by NCs. The average LOS was longer in patients experiencing NCs. The 1-, 3- and 5-year graft survival and patient survival were similar in patients with or without a NC. Multivariate analysis showed the following as independent risk factors for NC: a MELD score ≥20 (OR = 1.934, CI = 1.186-3.153) and an immunosuppressive regimen based on calcineurin inhibitors (CNIs) (OR = 1.669, CI = 1.009-2.760). Among patients receiving an everolimus-based immunosuppression, the 7.1% developed NCs, vs. the 16.9% in those receiving a CNI (P = 0.039). There was a 1-, 3- and 5-year NC-free survival of 81.7%, 81.1% and 77.7% in patients receiving a CNI-based regimen and 95.1%, 93.6% and 92.7% in those not receiving a CNI-based regimen (P < 0.001). In patients undergoing a LT and presenting with nonmodifiable risk factors for developing NCs, an immunosuppressive regimen based on CNIs is likely to result in a higher rate of NCs compared to mTOR inhibitors.

XIENCE V everolimus-eluting coronary stent system: a novel second generation drug-eluting stent

Drug-eluting stents (DES) have been shown to be safe and significantly reduce clinical events and angiographic restenosis in the percutaneous treatment of coronary artery disease. Currently, three DES have been approved in Europe and Northern America: the sirolimus-eluting stent (SES), the paclitaxel-eluting stent (PES) and the zotarolimus-eluting stent (ZES). Everolimus, an analog of sirolimus, is an immunosuppressive and antiproliferative agent. In three studies, the SPIRIT I, FUTURE I and II, the everolimus-eluting stent has proven to be safe, well-tolerated and has shown very favorable clinical and angiographic results. Compared with earlier-generation DES, the XIENCE V everolimus-eluting coronary stent system (Advanced Cardiovascular Systems Inc., an Abbott Vascular Company, CA, USA) may provide enhanced deliverability, radiopacity with thinner strut filaments and, owing to a durable polymer, sustained drug elution and vascular compatibility.

Everolimus-coated tympanostomy tube on rat tympanic membrane

OBJECTIVES

Everolimus is an immunosuppressant and an antiproliferative macrolide agent which is used for coronary stent coating for local inhibition of in-stent restenosis. The aim of this study was to evaluate the effect of everolimus-coated tympanostomy tubes in rat tympanic membrane.

STUDY DESIGN

Prospective controlled animal study.

MATERIALS AND METHODS

Twenty-one Sprague-Dawley rats were included in the study. They were bilaterally myringotomized. An everolimus-coated fluoroplastic tympanostomy tube was inserted into one ear of each of the rats (everolimus-coated TT Group; n=21) and a standard fluoroplastic tympanostomy tube was applied to the contralateral ear of the same rats (Standard TT Group; n=21). Tympanic membranes and tubes were routinely examined otomicroscopically every other day for two months. Then the membranes were harvested and evaluated histologically.

RESULTS

In everolimus-coated tubes, the tube obstruction was found to be significantly lower than in standard tubes (p<0.05). The tube extrusion rate was less for everolimus-coated tubes than for standard tubes, but no statistically significant difference was observed between the two tubes. There was no statistically significant difference in the incidence of otorrhea between two tubes. Histopathological examination under light microscope revealed that everolimus-coated tubes resulted in less fibrosis and less inflammation in tympanic membranes than standard tubes (p<0.01).

CONCLUSION

The study shows the potential role of everolimus-coating of tympanostomy tubes in reducing tube obstruction. In addition, inflammatory reaction and fibrosis were observed to be significantly less with these tubes.

A novel platinum chromium everolimus-eluting stent for the treatment of coronary artery disease

The development of coronary stents represents a major step forward in the treatment of obstructive coronary artery disease since the introduction of percutaneous coronary intervention. The initial enthusiasm for bare metal stents was, however, tempered by a significant incidence of in-stent restenosis, the manifestation of excessive neointima hyperplasia within the stented vessel segment, ultimately leading to target vessel revascularization. Later, drug-eluting stents, with controlled local release of antiproliferative agents, consistently reduced this need for repeat revascularization. In turn, the long-term safety of first-generation drug-eluting stents was brought into question with the observation of an increased incidence of late stent thrombosis, often presenting as myocardial infarction or sudden death. Since then, new drugs, polymers, and platforms for drug elution have been developed to improve stent safety and preserve efficacy. Development of a novel platinum chromium alloy with high radial strength and high radiopacity has enabled the design of a new, thin-strut, flexible, and highly trackable stent platform, while simultaneously improving stent visibility. Significant advances in polymer coating, serving as a drug carrier on the stent surface, and in antiproliferative agent technology have further improved the safety and clinical performance of newer-generation drug-eluting stents. This review will provide an overview of the novel platinum chromium everolimus-eluting stents that are currently available. The clinical data from major clinical trials with these devices will be summarized and put into perspective.

Influence of Everolimus on Steady-State Pharmacokinetics of Cyclosporine in Maintenance Renal Transplant Patients

To investigate possible interactions of the novel immunosuppressant everolimus with cyclosporine, a multicenter, randomized, double-blind, placebo-controlled, dose-escalating phase I study was performed. Everolimus regimens (0.75-10 mg/d) were administered for 28 days to stable renal allograft recipients receiving the microemulsion form of cyclosporine. Steady-state cyclosporine profiles were assessed at baseline on day 0 (cyclosporine alone) and on day 21 with everolimus on steady state. By day 21, mean dose-normalized cyclosporine AUC0-12 increased by 15% in patients receiving placebo. In everolimus-treated patients, mean increases in cyclosporine AUC0-12 ranged from 7% to 43%, which were not significantly different across all dosing cohorts including placebo. Linear regression of everolimus AUC on day 21 versus the increase in cyclosporine AUC0-12 yielded a slope not significantly different from a horizontal line (P = ns). In conclusion, these results suggest that steady-state everolimus exposure over the wide range assessed in this study did not affect steady-state cyclosporine pharmacokinetics.

A comprehensive review of everolimus clinical reports: a new mammalian target of rapamycin inhibitor

As new immunosuppressive agents are introduced to the market, clinicians are faced with the daunting task of sifting through the published literature to decide the value that the agent will add to their own practice. We often must extrapolate information provided through study in other solid-organ transplantation populations than our specific area of interest as we interpret the results and outcomes. With these challenges in mind, this compilation of published work for the newest mammalian target of rapamycin inhibitor everolimus (Certican; Novartis Pharmaceuticals, Hanover, NJ) (Zortress; Novartis Pharmaceuticals, Basel, Switzerland) is intended to provide a concise but thorough presentation of available literature so that the reader who may be unfamiliar with the agent can make their own judgment. Both Ovid and PubMed search engines were queried with a particular focus on high-impact articles noted in the Web of Science or Citation Index. Work described solely in abstract or case report form was excluded, as well as meta-analyses or those that were editorial or commentary in nature. Included were publications presented using the English language that described adult human subjects who received a heart, lung, kidney, or liver allograft. The goal of this strategy was to allow for the inclusion of pertinent literature in an unbiased fashion. Tables are provided that outline trial specific information, leaving a discussion of major outcomes to the text of the review.

Monitoring of nonsteroidal immunosuppressive drugs in patients with lung disease and lung transplant recipients: American College of Chest Physicians evidence-based clinical practice guidelines

OBJECTIVES

Immunosuppressive pharmacologic agents prescribed to patients with diffuse interstitial and inflammatory lung disease and lung transplant recipients are associated with potential risks for adverse reactions. Strategies for minimizing such risks include administering these drugs according to established, safe protocols; monitoring to detect manifestations of toxicity; and patient education. Hence, an evidence-based guideline for physicians can improve safety and optimize the likelihood of a successful outcome. To maximize the likelihood that these agents will be used safely, the American College of Chest Physicians established a committee to examine the clinical evidence for the administration and monitoring of immunosuppressive drugs (with the exception of corticosteroids) to identify associated toxicities associated with each drug and appropriate protocols for monitoring these agents.

METHODS

Committee members developed and refined a series of questions about toxicities of immunosuppressives and current approaches to administration and monitoring. A systematic review was carried out by the American College of Chest Physicians. Committee members were supplied with this information and created this evidence-based guideline.

CONCLUSIONS

It is hoped that these guidelines will improve patient safety when immunosuppressive drugs are given to lung transplant recipients and to patients with diffuse interstitial lung disease.

Two-year results of a durable polymer everolimus-eluting stent in de novo coronary artery stenosis (The SPIRIT FIRST Trial)

AIMS

The successful use of everolimus on a durable polymer was earlier reported with 6 and 12 months data from this first-in-man study. This reports the long-term follow-up of the XIENCE V everolimus-eluting stent.

METHODS AND RESULTS

This prospective, single-blinded, randomised, multicentre clinical trial evaluated the safety and efficacy of the XIENCE V everolimus-eluting coronary stent system versus an identical bare metal stent in the treatment of patients with a single de novo coronary artery stenosis of >/=50% and <100% and a vessel diameter of 3.0 mm as assessed by on-line quantitative coronary angiography that could be covered by a single 18 mm stent.Sixty patients were randomised and at two-year follow-up, clinical data was available in 96% and 97% of patients in the everolimus and control arm, respectively. Four patients were excluded due to protocol violations and two patients withdrew consent.In the everolimus arm no additional death, myocardial infarction, clinically driven TLR, or TVR events were observed between one and two-year follow-up. The 2-year hierarchical MACE rate for the everolimus arm remained 15.4% (4/26). In the control group, two patients had a clinically driven target lesion revascularisation. MACE rate increased from 21.4% (6/28) to 25.0% (7/28) in the control group.

CONCLUSIONS

This report confirms and extends the safety and efficacy results of the durable polymer XIENCE V everolimus-eluting stent up to two years as compared to identical bare metal stents.

Individualized immunosuppression in transplant patients: potential role of pharmacogenetics

The immunosuppressive drugs used to prevent the rejection of transplanted organs have a narrow therapeutic index. Under treatment results in episodes of rejection leading to either damage or loss of the organ. Over immunosuppression increases the risk of infection and malignancy as well as drug specific complications including diabetes mellitus and nephrotoxicity. There is wide variation in the drug dose required to achieve target blood concentrations and there is often dissociation between pharmacokinetics and pharmacodynamics. Currently, immunosuppressive drug treatment is individualized based on a clinical assessment of the risk of rejection or toxicity. Therapeutic drug monitoring is routinely employed for several immunosuppressive drugs. Pharmacogenetics has the potential to complement therapeutic drug monitoring but clinical benefit has yet to be demonstrated. Novel biomarker-based approaches to risk stratification and pharmacodynamic monitoring are under development and are ready for clinical trials.

Fifty years in the vineyard of transplantation: looking back

The past 5 decades have documented remarkable advances in basic knowledge and clinical expertise in transplantation. The first 12 years of this half century of my participation in the enterprise were consumed with the isolation, chemical characterization, and application of histocompatibility antigens purified from mouse, guinea pig, and human tissues, demonstrating that their specificity was based on unique amino acid sequences in protein structures. Initial unsuccessful attempts to use native molecules to induce tolerance in rat renal or heart transplantation models were followed by limited success when they were administered with a brief perioperative course of cyclosporine (CsA). Production of allochimeric constructs of class I major histocompatibility complex molecules bearing donor-type amino acid substitutions into the host-type C-terminal portion of the α1 helix yielded tolerogens whose activity was not dependent on conditioning with CsA or total lymphoid irradiation (TLI). The allochimeric molecules serve as altered peptide ligands that induce an aberrant T-cell signal 1 response producing transplantation tolerance. The potent activity of CsA in this experimental model was extended to clinical settings. Pharmacologic tools were employed to explore intra- and interindividual variations in drug exposure leading to the development of a better drug formulation. However, the intrinsic nephrotoxicity of CsA necessitated marked 80% reductions in de novo drug exposure as were achieved by exploiting the synergistic pharmacodynamic and pharmacokinetic interactions of CsA with sirolimus. The final decade in this 50-year experience includes editorship of this journal with marked changes in its direction. These experiences have afforded insights into future avenues for preclinical exploration and therapeutic drug development.

Safety and efficacy of everolimus in adult patients with neuroendocrine tumors

Neuroendocrine tumors (NETs) consist of a diverse family of tumors which are derived from the neuroendocrine system. Most NETs are well or moderately differentiated tumors with a relatively indolent growth pattern. However, these tumors can cause significant clinical disease due to release of functional products that mediate the carcinoid syndrome and other diverse sequela. They also can grow progressively and cause symptoms from local invasion or distant metastasis. NETs are optimally treated with surgery and somatosatin analogs (SSA’s) to control symptoms but are relatively insensitive to systemic chemotherapy. As a result, patients with advanced unresectable NETs have a poor prognosis. In 2011, two targeted therapies, sunitinib and everolimus were approved in the subset of progressive pancreatic NETs (pNETs). Everolimus is an oral inhibitor of the growth stimulatory mTOR pathway. In Phase 2 trials in NETs and pNETs, everolimus was well tolerated and associated with some response and widespread disease stabilization. In follow-up, randomized Phase 3 trials, everolimus was compared to placebo. In the RADIANT-2 trial, everolimus and a somatostatin analog were used in patients with functional NETs and treatment was associated with an an improvement in progression-free survival (PFS). In the RADIANT-3 trial, patients with pNET were randomized to receive everolimus or placebo along with best supportive care. Everolimus was again associated with improvement in PFS compared to placebo and it has been approved by the FDA for patients with progressive pNET. Everolimus is associated with frequent low grade toxicity but is also notable for increased rates of infection as well as non-infectious pneumonitis. mTOR inhibition with everolimus represents a significant advance in the treatment of advanced neuroendocrine tumors.

Everolimus-eluting stents: update on current clinical studies

Everolimus-eluting stents (EES) have become the most commonly implanted coronary stents worldwide. This review describes and analyzes the clinical data supporting the use of EES, focusing primarily on published, randomized, controlled trials. Everolimus-eluting stents have been shown to have less restenosis, stent thrombosis, and periprocedural myocardial infarction compared with earlier generation paclitaxel-eluting stents (PES). Lower rates of adverse events for EES compared with PES were generally seen in all subgroups, with the notable exception of patients with diabetes mellitus. There have been fewer, randomized, clinical trials comparing EES with either sirolimus-eluting stents or zotarolimus-eluting stents, although very good results with EES have been observed in the trials that have been performed. Recent clinical trial data suggest that this excellent safety and efficacy profile is maintained in a next-generation EES designed to have improved mechanical properties and radiopacity.

Once daily everolimus is safe and effective in de novo renal transplant recipients: six-month results of a pilot study

INTRODUCTION

The half-life of everolimus is approximately 28 hours, but everolimus is normally administered twice a day. The aim of this prospective, single-center, exploratory study was to compare the efficacy and safety of a once a day (OD) everolimus regimen versus the standard twice a day regimen (BID) for immunosuppressive therapy in renal transplantation.

METHODS

Forty de novo renal transplant recipients prospectively assigned to OD (n = 21) or BID (n = 19) were followed for 6 months. In the OD group, everolimus was given orally once a day to target a trough blood level of 2-6 ng/mL. In the BID, group everolimus was given twice a day to target a trough blood level of 3-12 ng/mL. All patients also received induction treatment with basiliximab and low-dose calcineurin inhibitors.

RESULTS

At 6 months follow-up, patient and graft survivals were 100%; renal function and acute rejection rates were similar between the 2 regimens. Patients in the OD group showed significantly lower cholesterol and triglyceride levels compared with those in the BID group, namely, total cholesterol level, OD 212 +/- 54 versus BID 249 +/- 59 mg/dL (P < .05), and serum triglycerides, OD 162 +/- 72 versus BID 245 +/- 133 mg/dL (P < .02).

DISCUSSION

This study showed that OD administration of everolimus provided excellent patient and graft survivals and good renal function without an increased incidence of acute rejection episodes. The lipid profile was significantly better among patients receiving everolimus OD. These findings suggested that everolimus can be safely administered once a day.

Severe atopic dermatitis treated with everolimus

BACKGROUND

Patients with severe atopic dermatitis (AD) often require treatment with oral immunosuppressive drugs. Everolimus is a rapamycin-derived macrolide with immunosuppressive and antiproliferative effects. Everolimus demonstrated efficacy not only in the prophylaxis of organ rejection in kidney transplant patients, but also in decreasing disease activity in psoriasis patients.

OBJECTIVE

To evaluate whether everolimus is an effective treatment in patients with severe AD.

METHODS

Two patients with severe AD were treated with everolimus in combination with low-dose cyclosporin A (CsA) or prednisone. During treatment, a disease activity and safety laboratory examination was performed.

RESULTS

Everolimus either in combination with prednisone or with CsA did not result in improvement of disease activity in two patients with severe AD.

CONCLUSION

Everolimus does not seem to be an effective treatment in these two AD patients, either in combination with prednisone or with CsA.

Potentiating effects of RAD001 (Everolimus) on vincristine therapy in childhood acute lymphoblastic leukemia

Despite advances in the treatment of acute lymphoblastic leukemia (ALL), the majority of children who relapse still die of ALL. Therefore, the development of more potent but less toxic drugs for the treatment of ALL is imperative. We investigated the effects of the mammalian target of rapamycin inhibitor, RAD001 (Everolimus), in a nonobese diabetic/severe combined immunodeficiency model of human childhood B-cell progenitor ALL. RAD001 treatment of established disease increased the median survival of mice from 21.3 days to 42.3 days (P < .02). RAD001 together with vincristine significantly increased survival compared with either treatment alone (P < .02). RAD001 induced a cell-cycle arrest in the G(0/1) phase with associated dephosphorylation of the retinoblastoma protein, and reduced levels of cyclin-dependent kinases 4 and 6. Ultrastructure analysis demonstrated the presence of autophagy and limited apoptosis in cells of RAD001-treated animals. In contrast, cleaved poly(ADP-ribose) polymerase suggested apoptosis in cells from animals treated with vincristine or the combination of RAD001 and vincristine, but not in those receiving RAD001 alone. In conclusion, we have demonstrated activity of RAD001 in an in vivo leukemia model supporting further clinical development of target of rapamycin inhibitors for the treatment of patients with ALL.

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.

Next-generation drug-eluting stents in coronary artery disease: focus on everolimus-eluting stent (Xience V)

Percutaneous coronary revascularization has been a mainstay in the management of coronary artery disease since its introduction in the late 1970s. Bare-metal stents and, more recently, first-generation drug-eluting stents (DES), such as sirolimus-eluting (Cypher^®) and paclitaxel-eluting stents (Taxus^®), have further improved results of percutaneous coronary intervention (PCI) by improving early results and reducing the risk of restenosis. There is currently debate on the safety of these first-generation DES, given the potential for late stent thrombosis, especially after discontinuation of dual antiplatelet therapy. There are well known caveats on the performance of their respective metallic stent platforms, delivery, and dilation systems, and polymer coatings. Second-generation DES, such as zotarolimus-eluting (Endeavor^®) and everolimus-eluting stents (Xience V^®), have recently become available in the USA and/or Europe. The Xience V stent holds the promise of superior anti-restenotic efficacy as well as long-term safety. In addition, this stent is based on the Multi-link platform and delivery system. Recently available data already suggest the superiority of the Xience V stent in comparison to the Taxus stent in terms of prevention of restenosis, without significant untoward events. Nonetheless, the number of patients studied and the follow-up duration are still too limited to enable definitive conclusions. Only indirect meta-analyses can be used to date to compare the Xience V with the Cypher. This systematic review tries to provide a concise and critical appraisal of the data in support of the Xience V everolimus-eluting stent.

Comparison of fluorescent polarization immunoassay (FPIA) versus HPLC to measure everolimus blood concentrations in clinical transplantation

Clinical management of transplant patients depends on therapeutic drug monitoring (TDM) and regulation of immunosuppressive therapy. TDM of whole-blood concentrations is mandatory for everolimus (ERL) dosage individualisation. We compared the new semi-automated immunoassay (Innofluor Certican Assay System, Seradyn Inc) using FPIA technology on Abbott TDxFLx analyzers with established HPLC-UV as reference method. A total of 165 samples were analyzed from 52 transplant patients (40 kidney, 12 heart) receiving ERL or another immunosuppressive agent as part their routine care after organ transplantation. The correlation coefficient was r(2)=0.8229, and the regression equation (95% IC) yielded FPIA=1.111 x (HPLC)+0.378. FPIA compared to HPLC gave a positive bias of 1.19 ng/ml. The FPIA assay so appears to have a diagnostic efficacy comparable to HPLC for assessing the risk of acute rejection in transplant recipients. However, the values of the FPIA were higher than those calculated from HPLC measurements, because of the cross-reactivity of the antibody used in the FPIA assay with the ERL metabolite and/or with sirolimus; this cross-reactivity occurs frequently when transplant patients are switched from sirolimus to ERL.

Everolimus in Pulmonary Transplantation: Pharmacokinetics and Exposure–Response Relationships

BACKGROUND

In this study we evaluated exposure, safety and efficacy data from an international trial of everolimus. We sought to identify a tolerated and efficacious range for blood levels of this agent in maintenance lung transplant recipients.

METHODS

In a randomized, double-blind, multicenter trial, 213 maintenance lung transplant recipients received either everolimus 1.5 mg twice daily (n = 101) or azathioprine 1 to 3 mg/kg/day (n = 112) with cyclosporine and corticosteroids. At 15 visits over the first 2 years of the trial, we obtained 826 everolimus trough (C0) blood samples. We used median-effect analysis to assess relationships between everolimus C0 vs efficacy and safety responses.

RESULTS

Everolimus administration began at 1.5 mg twice daily and was progressively lowered over the first 2 months to an average of 1.2 +/- 0.4 mg twice daily, which was maintained thereafter. This dose yielded median C0 levels of 6.6 ng/ml (10th to 90th percentiles: 2.8 to 11.8 ng/ml). Over this range of everolimus C0, freedom from a decline in pulmonary function with bronchiolitis obliterans syndrome and freedom from biopsy-proven acute rejection were both > or = 88%. The incidence of increased cholesterol (> 6.5 mmol/liter), increased triglycerides (> 2.9 mmol/liter) and transiently decreased platelet count (< 100 x 10(9)/liter) rose significantly with increasing C0. Infections and drug-related adverse events were not significantly related to exposure.

CONCLUSIONS

A tolerated and efficacious concentration range for everolimus in maintenance lung transplantation appears to be 3 to 12 ng/ml when used in conjunction with cyclosporine and corticosteroids. This range should be prospectively assessed with possible refinement as more clinical experience is gained.

Everolimus

Everolimus (Certican) is an orally administered mammalian target of rapamycin inhibitor (proliferation signal inhibitor) derived from sirolimus (rapamycin), which is used as part of immunosuppressant therapy in kidney and heart transplantation. When evaluated as part of triple therapy with ciclosporin and corticosteroids, everolimus showed equivalent efficacy to mycophenolate mofetil after renal transplantation, and superiority to azathioprine in cardiac transplant recipients, in terms of reducing efficacy failure after transplantation. Everolimus potentiates ciclosporin-associated nephrotoxicity, and it is recommended that concentration-controlled everolimus is used with reduced-dosage ciclosporin in order to limit renal toxicity while retaining immunosuppressive efficacy. Ongoing trials with everolimus, such as the evaluation of ciclosporin-withdrawal strategies, should help clarify its optimal usage. The use of everolimus may be associated with reduced rates of cytomegalovirus (CMV) infection and of cardiac allograft vasculopathy. Available data suggest that everolimus may be cost-neutral for healthcare providers.

Immunosuppressive agents in solid organ transplantation: Mechanisms of action and therapeutic efficacy

Effective immunosuppression is an essential pre-requisite for successful organ transplantation and improvements in outcome after transplantation have to a large extent been dependent on developments in immunosuppressive therapy. Here we provide an overview of the different immunosuppressive agents currently used in solid organ transplantation. A historical perspective on the development of immunosuppression for organ transplantation is followed by a review of the individual agents, with a focus on their mechanism of action and efficacy. Steroids, anti-proliferative agents (azathioprine and mycophenolate), calcineurin inhibitors (cyclosporine and tacrolimus) and TOR inhibitors (sirolimus and everolimus) are discussed along with both polyclonal and monoclonal antibody preparations. Many of the key clinical trials that underpin current clinical usage of these agents are described and side-effects of the different agents are highlighted. Finally, a number of newer agents still in various stages of clinical development are briefly considered.

The Role of Therapeutic Monitoring of Everolimus in Solid Organ Transplantation

Everolimus is a novel proliferation signal inhibitor used in immunosuppressive therapies for the prevention of acute and chronic rejection. A role for everolimus drug monitoring has been suggested because of the potential for improving efficacy and reducing adverse effects. Everolimus has proven efficacy for prevention of rejection in adult de novo renal and cardiac transplant recipients. Similar effects have been shown in pediatric renal transplant patients. Several analytic methods are available to quantify everolimus concentrations. A good relationship exists between everolimus concentration and pharmacological response. Mere clinical monitoring of efficacy is insufficient because clinical presentations of graft rejection vary for each patient and are nonspecific. Thus, the authors have used a previously published 9-step decision-making algorithm to evaluate the utility of therapeutic drug monitoring for everolimus. The recommended therapeutic range for everolimus is a trough concentration of 3 to 8 ng/mL, as concentrations over 3 ng/mL have been associated with a decreased incidence of rejection, and concentrations >8 ng/mL with increased toxicity. Everolimus exhibits interindividual pharmacokinetic variability. African American patients have higher apparent clearance, whereas patients with hepatic dysfunction or those on concomitant medications with potent cytochrome P450 (CYP) 3A4 inhibitor or inducer properties have lower or higher apparent clearance, respectively. Solid organ transplant recipients will likely be maintained on immunosuppressant therapy for the life of the graft and/or recipient and thus are likely to benefit from clinical pharmacokinetic monitoring. Based on the available evidence, therapeutic drug monitoring for everolimus may provide additional information on efficacy and safety than sound clinical judgment alone. Patients on everolimus who have problems with absorption, who take concurrent cytochrome P450 inhibitors or inducers, or are noncompliant will attain the greatest benefit from drug monitoring.

Introducing Everolimus (Certican) in Organ Transplantation: An Overview of Preclinical and Early Clinical Developments

Everolimus (Certican) is a novel proliferation signal inhibitor with potent immunosuppressant effects that has been shown to prevent and reverse acute rejection in preclinical models of kidney, heart, and lung transplantation. These effects have been confirmed by clinical studies in which everolimus demonstrated comparable efficacy to azathioprine and mycophenolate mofetil in heart and renal transplantation, respectively, when combined with full-dose cyclosporine (CsA; Neoral). Experimental studies have also shown that everolimus inhibits smooth muscle cell proliferation and prevents neointimal thickening and transplant arteriosclerosis. Importantly, everolimus was shown to significantly reduce both the incidence and severity of cardiac allograft vasculopathy in recipients of heart transplants, which if confirmed in long-term studies, could provide a major advantage in these patients. Use of everolimus was also associated with lower rates of cytomegalovirus infection in both indications. Studies in which everolimus was combined with reduced-exposure CsA have demonstrated significantly improved renal function when compared with full-dose regimens, with no loss of efficacy. The results of preclinical and clinical studies with everolimus thus indicate that this novel proliferation signal inhibitor will be an important addition to the armamentarium by enhancing graft survival and minimizing toxicity.

mTOR-targeted therapy of cancer with rapamycin derivatives

Rapamycin and its derivatives (CCI-779, RAD001 and AP23576) are immunosuppressor macrolides that block mTOR (mammalian target of rapamycin) functions and yield antiproliferative activity in a variety of malignancies. Molecular characterization of upstream and downstream mTOR signaling pathways is thought to allow a better selection of rapamycin-sensitive tumours. For instance, a loss of PTEN functions results in Akt phosphorylation, cell growth and proliferation; circumstances that can be blocked using rapamycin derivatives. From recent studies, rapamycin derivatives appear to display a safe toxicity profile with skin rashes and mucositis being prominent and dose-limiting. Sporadic activity with no evidence of dose-effect relationship has been reported. Evidence suggests that rapamycin derivatives could induce G1-S cell cycle delay and eventually apoptosis depending on inner cellular characteristics of tumour cells. Surrogate molecular markers that could be used to monitor biological effects of rapamycin derivatives and narrow down biologically active doses in patients, such as the phosphorylation of P70S6K or expression of cyclin D1 and caspase 3, are currently evaluated. Since apoptosis induced by rapamycin is blocked by BCL-2, strategies aimed at detecting human tumours that express BCL-2 and other anti-apoptotic proteins might allow identification of rapamycin-resistant tumours. Finally, we discuss current and future placements of rapamycin derivatives and related translational research into novel therapeutic strategies against cancer.

Current and future immunosuppressive strategies in renal transplantation

The past decade has witnessed the introduction of several new immunosuppressive agents. The availability of these new pharmacologic offerings has not diminished the challenge of achieving a balance of adequate graft protection while minimizing the consequences of excessive immunosuppression. For renal transplant recipients, maintenance immunosuppression generally consists of a calcineurin inhibitor in combination with an antiproliferative agent and a corticosteroid; more recently, mammalian target of rapamycin inhibitors have been used. Excellent results have been achieved at many transplant centers with combinations of these agents in a variety of protocols. Regimens designed to limit or eliminate calcineurin inhibitor and/or corticosteroid therapy are actively being pursued in the transplant community. Allograft tolerance and xenotransplantation are being studied, and the knowledge gained from the effort may help in the development of innovative strategies and new immunosuppressive agents.