mTOR inhibitor-associated dermatologic and mucosal problems

Acneiform Eruptions Possibly Triggered by Clarithromycin During Sirolimus Treatment

Acneiform eruption is the recognized dermatological side effect of sirolimus, an inhibitor of the mammalian target of rapamycin, although the pathophysiological mechanisms and dose dependency of this side effect remain unclear. This case report describes a case of a 40-year-old Japanese woman treated with systemic sirolimus who developed acneiform eruptions following the administration of clarithromycin. The acneiform eruption resolved after discontinuation of sirolimus and relapsed with the resumption. Since sirolimus and clarithromycin have a potential drug-drug interaction mediated by cytochrome P450 3A (CYP3A), this case suggests that the acneiform eruption developed in association with elevated blood levels of sirolimus. We conclude that clinicians should be aware of the possibility of developing acneiform eruption during sirolimus treatment, especially when administered with medications that inhibit CYP3A.

Prevalence and spectrum of infectious and inflammatory dermatologic conditions occurring in pediatric heart transplant patients on a predominantly mTOR-based immune suppressive regimen: A retrospective chart review

INTRODUCTION

Pediatric heart transplant patients are routinely followed in dermatology clinics due to elevated risk of cutaneous malignancy. However, transplant patients may experience other, non-cancer-related dermatologic conditions including skin infections, inflammatory diseases, and drug eruptions that can cause significant medical and psychosocial comorbidity.

METHODS

A retrospective chart review of all pediatric heart transplant patients at Mayo Clinic Children's Center in Rochester, MN, was performed to determine the prevalence and spectrum of non-cancer dermatologic conditions. Statistical analysis was conducted to look for associations between episodes of rejection and skin condition development.

RESULTS

Of the 65 patients who received heart transplants under the age of 18 and were followed at Mayo Clinic, 69% (N = 45) were diagnosed with at least one skin condition between transplant and the time of most recent follow-up. Sixty-two percent (N = 40) of patients were diagnosed with an inflammatory skin condition (most commonly acne and atopic dermatitis), 45% (N = 29) with an infectious skin condition (most commonly warts and dermatophyte infection), and 32% (N = 21) with a drug eruption (most commonly unspecified rash and urticaria). No association was found between presence of skin disease and number of rejection episodes.

CONCLUSIONS

Non-cancer dermatologic conditions are prevalent within pediatric heart transplant recipients and may directly impact their medical needs and quality of life. Dermatologist involvement in the care of post-transplant pediatric patients is important, not only for cancer screening but also for diagnosis and treatment of common infectious and inflammatory skin conditions.

The Role of mTOR Inhibitors after Liver Transplantation for Hepatocellular Carcinoma

Liver transplantation is a treatment option for nonresectable patients with early-stage HCC, with more significant advantages when Milan criteria are fulfilled. An immunosuppressive regimen is required to reduce the risk of graft rejection after transplantation, and CNIs represent the drugs of choice in this setting. However, their inhibitory effect on T-cell activity accounts for a higher risk of tumour regrowth. mTOR inhibitors (mTORi) have been introduced as an alternative immunosuppressive approach to conventional CNI-based regimens to address both immunosuppression and cancer control. The PI3K-AKT-mTOR signalling pathway regulates protein translation, cell growth, and metabolism, and the pathway is frequently deregulated in human tumours. Several studies have suggested the role of mTORi in reducing HCC progression after LT, accounting for a lower recurrence rate. Furthermore, mTOR immunosuppression controls the renal damage associated with CNI exposure. Conversion to mTOR inhibitors is associated with stabilizing and recovering renal dysfunction, suggesting an essential renoprotective effect. Limitations in this therapeutic approach are related to their negative impact on lipid and glucose metabolism as well as on proteinuria development and wound healing. This review aims to summarize the roles of mTORi in managing patients with HCC undergoing LT. Strategies to overcome common adverse effects are also proposed.

Main factors influencing long-term outcomes of liver transplantation in 2022

Liver transplant (LT) outcomes have markedly improved in the recent decades, even if long-term morbidity and mortality are still considerable. Most of late deaths are independent from graft function and different comorbidities, including complications of metabolic syndrome and de novo neoplasms, seem to play a key role in determining long-term outcomes in LT recipients. This review discusses the main factors associated with late mortality and suggests possible strategies to improve long-term management and follow-up after liver transplantation. In particular, the reduction of drug toxicity, the use of tools to identify high-risk patients, and setting up a multidisciplinary team also for long-term management of LT recipients may further improve survival after liver transplantation.

Topical Sirolimus 0.2% Gel for the Management of Tuberous Sclerosis Complex-Related Cutaneous Manifestations: An Interim Analysis of Postmarketing Surveillance in Japan

INTRODUCTION

Tuberous sclerosis complex (TSC) is a rare autosomal dominant genetic disorder affecting several organs, including skin. We sought to assess the real-world effectiveness and safety of a topical sirolimus 0.2% gel treatment for TSC-related cutaneous manifestations.

METHODS

We conducted an interim analysis of postmarketing surveillance conducted in Japan over 52 weeks. A total of 635 and 630 patients were included in the safety and efficacy analysis sets, respectively. Improvement rate of overall cutaneous manifestations, responder rate of improvement in individual lesions, adverse events (AEs), adverse drug reactions (ADRs), and patient satisfaction level of topical sirolimus 0.2% gel treatment were evaluated along with patient characteristics associated with the improvement rate of cutaneous manifestations or safety.

RESULTS

The mean age of the patients was 22.9 years and 46.1% were men. At week 52 of treatment, the overall improvement rate was 74.8% and the responder rate was the highest for facial angiofibroma (86.2%). Overall, the incidence rates of AEs and ADRs were 24.6% and 18.4%, respectively. Efficacy was associated with age (< 15, ≥ 15 to < 65, and ≥ 65 years, p = 0.010), duration of use (p < 0.001), and total dosage (p = 0.005). Safety was associated with age (< 15, ≥ 15 to < 65, and ≥ 65 years, p = 0.011) and duration of use (p < 0.001). However, when the broad age group (≥ 15 to < 65) was subcategorized by 10-year intervals, the incidence of ADRs was similar among the age groups with no significant differences. Hepatic or renal impairment or concomitant use of systemic mTOR inhibitors had no effect on the effectiveness or safety. Overall, 53% of patients were "very satisfied" or "satisfied" with the treatment received.

CONCLUSIONS

Topical sirolimus 0.2% gel is effective in the management of TSC-related cutaneous manifestations and generally well tolerated. Age and duration of usage had a significant association with the effectiveness or safety of topical sirolimus 0.2% gel, whereas total dosage had a significant association with the effectiveness.

Expression of γ-globin genes in β-thalassemia patients treated with sirolimus: results from a pilot clinical trial (Sirthalaclin)

Introduction

β-thalassemia is caused by autosomal mutations in the β-globin gene, which induce the absence or low-level synthesis of β-globin in erythroid cells. It is widely accepted that a high production of fetal hemoglobin (HbF) is beneficial for patients with β-thalassemia. Sirolimus, also known as rapamycin, is a lipophilic macrolide isolated from a strain of Streptomyces hygroscopicus that serves as a strong HbF inducer in vitro and in vivo. In this study, we report biochemical, molecular, and clinical results of a sirolimus-based NCT03877809 clinical trial (a personalized medicine approach for β-thalassemia transfusion-dependent patients: testing sirolimus in a first pilot clinical trial, Sirthalaclin).

Methods

Accumulation of γ-globin mRNA was analyzed using reverse-transcription quantitative polymerase chain reaction (PCR), while the hemoglobin pattern was analyzed using high-performance liquid chromatography (HPLC). The immunophenotype was analyzed using a fluorescence-activated cell sorter (FACS), with antibodies against CD3, CD4, CD8, CD14, CD19, CD25 (for analysis of peripheral blood mononuclear cells), or CD71 and CD235a (for analysis of in vitro cultured erythroid precursors).

Results

The results were obtained in eight patients with the β+/β+ and β+/β0 genotypes, who were treated with a starting dosage of 1 mg/day sirolimus for 24-48 weeks. The first finding of this study was that the expression of γ-globin mRNA increased in the blood and erythroid precursor cells isolated from β-thalassemia patients treated with low-dose sirolimus. This trial also led to the important finding that sirolimus influences erythropoiesis and reduces biochemical markers associated with ineffective erythropoiesis (excess free α-globin chains, bilirubin, soluble transferrin receptor, and ferritin). A decrease in the transfusion demand index was observed in most (7/8) of the patients. The drug was well tolerated, with minor effects on the immunophenotype, and an only side effect of frequently occurring stomatitis.

Conclusion

The data obtained indicate that low doses of sirolimus modify hematopoiesis and induce increased expression of γ-globin genes in a subset of patients with β-thalassemia. Further clinical trials are warranted, possibly including testing of the drug in patients with less severe forms of the disease and exploring combination therapies.

Novel Targeted Therapies for Metastatic Thyroid Cancer-A Comprehensive Review

The knowledge on thyroid cancer biology has grown over the past decade. Thus, diagnostic and therapeutic strategies to manage thyroid cancer are rapidly evolving. With new insights into tumor biology and cancer genetics, several novel therapies have been approved for the treatment of thyroid cancer. Tyrosine kinase inhibitors (TKIs), such as lenvatinib and sorafenib, have been successfully utilized for the treatment of radioactive iodine (RAI)-refractory metastatic differentiated thyroid cancer (DTC). In addition, pretreatment with mitogen-activated protein kinase (MAPK) inhibitors (trametinib and selumetinib) has been shown to restore RAI avidity in previously RAI-refractory DTCs. Local therapies, such as external beam radiation and radiofrequency/ethanol ablation, have also been employed for treatment of DTC. Vandetanib and cabozantinib are the two TKIs currently approved by the Food and Drug Administration (FDA) for the treatment of medullary thyroid cancer (MTC). Other novel therapies, such as peptide receptor radionuclide therapy and carcinoembryonic antigen (CEA) vaccine, have also been utilized in treating MTC. Ongoing trials on selective rearranged-during-transfection (RET) protooncogene inhibitors, such as LOXO-292 and BLU-667, have demonstrated promising results in the treatment of metastatic MTC resistant to non-selective TKIs. The FDA-approved BRAF/MEK inhibitor combination of dabrafenib and trametinib has revolutionized treatment of BRAFV600E mutation positive anaplastic thyroid cancer. Several other emerging classes of medications, such as gene fusion inhibitors and immune checkpoint inhibitors, are being actively investigated in several clinical trials. In this review, we describe the molecular landscape of thyroid cancer and novel targeted therapies and treatment combinations available for the treatment of metastatic thyroid cancer.

Oral Mucosal Injury Caused by Targeted Cancer Therapies

Targeted cancer therapies have fundamentally transformed the treatment of many types of cancers over the past decade, including breast, colorectal, lung, and pancreatic cancers, as well as lymphoma, leukemia, and multiple myeloma. The unique mechanisms of action of these agents have resulted in many patients experiencing enhanced tumor response together with a reduced adverse event profile as well. Toxicities do continue to occur, however, and in selected cases can be clinically challenging to manage. Of particular importance in the context of this monograph is that the pathobiology for oral mucosal lesions caused by targeted cancer therapies has only been preliminarily investigated. There is distinct need for novel basic, translational, and clinical research strategies to enhance design of preventive and therapeutic approaches for patients at risk for development of these lesions. The research modeling can be conceptually enhanced by extrapolating "lessons learned" from selected oral mucosal conditions in patients without cancer as well. This approach may permit determination of the extent to which pathobiology and clinical management are either similar to or uniquely distinct from oral mucosal lesions caused by targeted cancer therapies. Modeling associated with oral mucosal disease in non-oncology patients is thus presented in this context as well. This article addresses this emerging paradigm, with emphasis on current mechanistic modeling and clinical treatment. This approach is in turn designed to foster delineation of new research strategies, with the goal of enhancing cancer patient treatment in the future.

Sirolimus and mTOR Inhibitors: A Review of Side Effects and Specific Management in Solid Organ Transplantation

Inhibitors of mechanistic target of rapamycin (mTOR inhibitors) are used as antiproliferative immunosuppressive drugs and have many clinical applications in various drug combinations. Experience in transplantation studies has been gained regarding the side effect profile of these drugs and the potential benefits and limitations compared with other immunosuppressive agents. This article reviews the adverse effects of mTOR inhibitors in solid organ transplantation, with special attention given to mechanisms hypothesized to cause adverse events and their management strategies.

Cutaneous reactions to targeted therapies in children with CNS tumors: A cross-sectional study

BACKGROUND

MAPK (RAS-RAF-MEK-ERK-MAP) and mTOR inhibitors are novel treatments for pediatric central nervous system (CNS) tumors. The literature on common cutaneous adverse reactions to these therapies is sparse in the pediatric population. The aim of this study was to describe common cutaneous adverse reactions to BRAF, MEK, and mTOR inhibitors in children with CNS tumors.

METHODS

In this cross-sectional study, patients younger than 21 years of age receiving BRAF, MEK, and mTOR inhibitor monotherapy for a CNS tumor were enrolled over a one-year period. Full body skin examination, photographs of dermatologic findings, and initial treatment recommendations were included at the initial visit, and follow-up skin examinations were recommended every three months.

RESULTS

Twenty-two patients were enrolled in the study. Fifty percent (11/22) received trametinib, a MEK inhibitor, 27.3% (6/22) received dabrafenib, a BRAF inhibitor, and 22.7% (5/22) received everolimus, an mTOR inhibitor. Median age at visit was 11 years (range, 3-19). Median time from treatment initiation to skin examination was 4.5 months (range, 0-43). Ninety-six percent (21/22) of all patients had at least one skin reaction. The most common reactions across treatment groups included follicular/acneiform eruptions and xerosis. Two patients on MEK inhibitors and one patient on a BRAF inhibitor required therapy cessation due to severe cutaneous reactions.

CONCLUSIONS

Cutaneous reactions to targeted anticancer therapy in children are common, treatable, and rarely require drug dose reduction or discontinuation. Routine surveillance and early intervention may improve quality of life and facilitate continuation of life-saving therapy.

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.

Dermatological Complications After Solid Organ Transplantation

Organ transplant recipients (OTRs) are a population at high risk for cutaneous adverse events. Their early recognition and appropriate treatment is an important component of the clinical management of OTRs and should be optimally dealt with by dermatologists working in the context of a transplant dermatology clinic. Skin examination should be a standard procedure before performing organ transplantation to assess conditions which may be difficult to manage after the transplant procedure has been performed or which may represent a contraindication to transplantation, e.g., malignant melanoma. It also offers an opportunity to educate patients on skin care after organ transplantation. Skin infections can occur at any time after organ transplantation and include viral, bacterial, and fungal opportunistic infections. The risk of reactivation of latent viruses, such as varicella-zoster virus (VZV) and cytomegalovirus (CMV), is high. Bacterial infections are frequent and may be caused by unusual agents such Actinomyces, Mycobacteria, Legionella, or Nocardia. A large spectrum of fungal infections may occur, ranging from superficial (e.g., dermatophytes) to deeper and more severe ones (Alternaria, Aspergillus, Cryptococcus, Histoplasma). Drug-related idiosyncratic reactions usually occur early after the introduction of the causative drug, e.g., hypersensitivity reaction to azathioprine. On the long-term run, cutaneous effects due to cumulative drug toxicity, e.g., sebaceous hyperplasia from cyclosporine, may appear. Rare immunologically driven inflammatory reactions may occur in OTRs such as GVH or autoimmune disease. Tumors are particularly frequent. Kaposi's sarcoma, associated with persistent human herpes virus 8 (HHV8) infection, and cutaneous anaplastic large-cell lymphoma (ALCL) occur early after transplantation. Other cancers, such as nonmelanoma skin cancer (NMSCs), associated with persistent human papillomavirus (HPV) infections, malignant melanoma, Merkel cell carcinoma, or adnexal tumors, manifest later with an incidence which is much higher than observed in the general population. The incidence increases further after a first NMSC occurs.

Airway plaque presenting after alteration of immunosuppression in a pediatric patient remote from heart transplantation

Success after solid organ transplantation is dependent on the proper balance of immunosuppression to prevent rejection of the allograft while limiting the risk of developing infections and malignancy. We present a 9-year-old girl, remote from transplant, who presented with airway plaque after a change in immunosuppression to include the mTOR inhibitor sirolimus. Differential diagnosis included direct medication side effect, infection, and neoplasia.

Cutaneous Toxicities From Transplantation-Related Medications

Despite the abundance of information on cutaneous malignancies associated with solid organ transplantation in the transplant literature, there is limited information regarding nonmalignant skin changes after transplantation. There are numerous skin toxicities secondary to immunosuppressive and other transplant-related medications that can vary in presentation, severity, and prognosis. To limit associated morbidity and mortality, solid organ transplant recipient care providers should effectively identify and manage cutaneous manifestations secondary to drug toxicity. Toxicities from the following transplant-related medications will be discussed: antithymocyte globulins, systemic steroids, cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, mammalian target of rapamycin inhibitors sirolimus and everolimus, basiliximab and daclizumab, belatacept, and voriconazole.

Sirolimus-Associated Pruritus: Case Report and Review

Sirolimus is an immunosuppressant drug used to prevent organ rejection in transplant patients. We describe a man with sirolimus-associated pruritus and review the features of this adverse event in other individuals receiving this drug. The patient was a 67-year-old heart transplant recipient receiving sirolimus as part of his immunosuppressive regimen. He developed severe pruritus over the distal extremities, face, and earlobes six months after starting the drug. The symptoms became progressively worse as he continued to receive this medication. Temporary elimination of the drug resulted in cessation of his itching. Subsequently, sirolimus was discontinued and everolimus was started; this provided temporary relief of his pruritus. PubMed was used to review the following terms: “sirolimus”, “itch”, and “pruritus.” Relevant papers and their references were reviewed. We are aware of only one other patient in whom pruritus necessitated cessation of treatment with sirolimus. Systemic pruritus is a rare adverse event associated with sirolimus. It can occur in both heart and liver transplant patients, beginning several months after transplant, and typically persists. Dose reduction may improve symptoms. Discontinuation of the medication or use of alternative immunosuppressants may be necessary for complete symptom relief.

Oral mucosal changes induced by anticancer targeted therapies and immune checkpoint inhibitors

Development of biological targeted therapies and immune checkpoint inhibitors has redefined the treatment for many cancers; however, the increasing use of new protocols has led to physicians observing a new spectrum of toxicities. To date, oral adverse events induced by these new anticancer therapies have been mainly reported using nonspecific terminology ("stomatitis," "mucosal inflammation," "mucositis") and remain poorly characterized, with the exception of mammalian target of rapamycin (mTOR) inhibitor-associated stomatitis. Oral toxicities of targeted therapies often display very characteristic features which clearly differ from classic oral injuries observed with cytotoxic chemotherapy and/or radiotherapy. In addition, they frequently affect more than 20% of treated patients and can lead to a significant morbidity or permanent treatment discontinuation. Oral mucosal toxicities described in this review include mTOR inhibitor-associated stomatitis (mIAS); stomatitis, benign migratory glossitis, and osteonecrosis of the jaw associated with multi-targeted kinase inhibitors of the VEGF and PDGF receptors; mucositis induced by EGFR inhibitors (in monotherapy or in combination with head and neck radiotherapy and/or chemotherapy); hyperkeratotic lesions with BRAF inhibitors; pigmentary changes and lichenoid reactions secondary to imatinib; and more recent data on the "Osler-Weber-Rendu-like syndrome" described with the antibody-drug conjugate, TDM-1. Finally, we provide, to our knowledge, the first available structured data on oral toxicities induced by the new recently FDA- and EMA-approved monoclonal antibodies targeting PD-1. Clinical management of these targeted therapy-related oral changes is also discussed.

Efficacy and Safety of Everolimus for Maintenance Immunosuppression of Kidney Transplantation: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Conversion to everolimus is often used in kidney transplantation to overcome calcineurin inhibitor (CNI) nephrotoxicity but there is conflicting evidence for this approach.

OBJECTIVES

To investigate the benefits and harm from randomized clinical trials (RCTs) involving the conversion from CNI to everolimus after kidney transplantation.

METHODS

Databases were searched up to March 2016. Two reviewers independently assessed trials for eligibility and quality, and extracted data. Results are expressed as risk ratio (RR) or mean difference (MD) with 95% confidence intervals (CI).

RESULTS

Eleven RCTs, with a total of 1,633 patients, met the final inclusion criteria. Patients converted to everolimus had improved renal function at 1 year posttransplant with an estimated glomerular filtration rate (eGFR) of 5.36 mL/min per 1.73 m2 greater than patients remaining on CNI (p = 0.0005) and the longer-term results (> 1 year) of renal function was identical to that of 1 year. There was not a substantial difference in graft loss, mortality, and the occurrence of adverse events (AEs) or serious AEs. However, the risks of acute rejection and trial termination due to AEs with everolimus are respectively 1.82 and 2.63 times greater than patients staying on CNI at 1 year posttransplant (p = 0.02, p = 0.03, respectively). Further, those patients who converted to everolimus had a substantially greater risk of anemia, hyperlipidemia, hypercholesterolemia, hypokalemia, proteinuria, stomatitis, mouth ulceration, and acne.

CONCLUSIONS

Conversion from CNI to everolimus after kidney transplantation is associated with improved renal function in the first 5 years posttransplant but increases the risk of acute rejection at 1 year posttransplant and may not be well endured.

New frontiers in mucositis

Mucositis is among the most debilitating side effects of radiotherapy, chemotherapy, and targeted anticancer therapy. Research continues to escalate regarding key issues such as etiopathology, incidence and severity across different mucosae, relationships between mucosal and nonmucosal toxicities, and risk factors. This approach is being translated into enhanced management strategies. Recent technology advances provide an important foundation for this continuum. For example, evolution of applied genomics is fostering development of new algorithms to rapidly screen genomewide single-nucleotide polymorphisms (SNPs) for patient-associated risk prediction. This modeling will permit individual tailoring of the most effective, least toxic treatment in the future. The evolution of novel cancer therapeutics is changing the mucositis toxicity profile. These agents can be associated with unique mechanisms of mucosal damage. Additional research is needed to optimally manage toxicity caused by agents such as mammalian target of rapamycin (mTOR) inhibitors and tyrosine kinase inhibitors, without reducing antitumor effect. There has similarly been heightened attention across the health professions regarding clinical practice guidelines for mucositis management in the years following the first published guidelines in 2004. New opportunities exist to more effectively interface this collective guideline portfolio by capitalizing upon novel technologies such as an Internet-based Wiki platform. Substantive progress thus continues across many domains associated with mucosal injury in oncology patients. In addition to enhancing oncology patient care, these advances are being integrated into high-impact educational and scientific venues including the National Cancer Institute Physician Data Query (PDQ) portfolio as well as a new Gordon Research Conference on mucosal health and disease scheduled for June 2013.

Safety of mTOR inhibitors in adult solid organ transplantation

INTRODUCTION

Mammalian target of rapamycin (mTOR) inhibitors (sirolimus and everolimus) are a class of immunosuppressive drugs approved for solid organ transplantation (SOT). By inhibiting the ubiquitous mTOR pathway, they present a peculiar safety profile. The increased incidence of serious adverse events in early studies halted the enthusiasm as a kidney sparing alternative to calcineurin inhibitors (CNI).

AREAS COVERED

Herein we review mTOR inhibitors safety profile for adult organ transplantation, ranging from acute side effects, such as lymphoceles, delayed wound healing, or cytopenias, to long-term ones which increase morbidity and mortality, such as cancer risk and metabolic profile. Infection, proteinuria, and cutaneous safety profiles are also addressed.

EXPERT OPINION

In the authors' opinion, mTOR inhibitors are a safe alternative to standard immunosuppression therapy with CNI and mycophenolate/azathioprine. Mild adverse events can be easily managed with an increased awareness and close monitoring of trough levels. Most serious side effects are dose- and organ-dependent. In kidney and heart transplantation mTOR inhibitors may be safely used as either low-dose de novo or through early-conversion. In the liver, conversion 4 weeks post-transplantation may reduce long-term chronic kidney disease secondary to calcineurin nephrotoxicity, without increasing hepatic artery/portal vein thrombosis.

New drugs, new challenges for dermatologists: mucocutaneous ulcers secondary to everolimus

Everolimus, a mammalian target of rapamycin inhibitor, is an emerging drug, which is being increasingly applied in oncology and solid organ transplantation. Oral ulcers are a frequent side effect associated with this immunosupressor. We report the case of a renal transplant recipient who developed disfiguring oral and perianal ulcers secondary to everolimus's toxicity. This is probably the first report of perianal involvement. Dermatologists need to be aware of the potential mucocutaneous adverse effects related to these new drugs that are becoming evermore common in our clinical practice.

Sirolimus as Long-term Graft-versus-host-disease Prophylaxis in Haploidentical Hematopoietic Stem Cell Transplant Recipients for Non-malignant Disorders is Associated with High Incidence of Acneiform Lesions

Background:

Sirolimus has provided the option for calcineurin inhibitor (CNI)-free immunosuppressive therapy in both solid organ transplant (SOT) and hematopoietic stem cell transplantation (HSCT). However, long-term use of sirolimus has been reported to be associated with a high incidence of cutaneous side effects in SOT, particularly acneiform lesions.

Materials and Methods:

We studied the incidence of acneiform lesions and the risk factors in 41 HSCT recipients between ages 4 and 64 years, undergoing HSCT for malignant (n = 29) and non-malignant diseases (n = 12) from haploidentical family donors.

Results:

Seven patients developed acneiform lesions at the median of 85 days (range, 45–105 days). Acneiform lesions occurred in 6/11 patients on sirolimus and in only 1/30 patients not receiving sirolimus (P = 0.001). This was more frequent in patients with non-malignant disorders (5/12 versus 2/29, P = 0.01) and those receiving graft from female donors (7/23 versus 0/18, P = 0.01).

Conclusions:

Despite being frequently reported in SOT, this is the first such report in HSCT. Our study suggests that prolonged use of sirolimus might be associated with high incidence of acneiform lesions in haploidentical HSCT recipients with non-malignant diseases, particularly in those receiving graft from a female donor. We discuss the possible reasons for these findings and the putative mechanism of acneiform lesions in these patients

Overview and management of toxicities associated with systemic therapies for advanced renal cell carcinoma

The advent of novel targeted agents for metastatic renal cell carcinoma (RCC) has offered clinical benefits over traditional immunotherapy (e.g., interleukin-2 and interferon-α) in both efficacy and safety profiles. The major classes of these targeted therapies for metastatic RCC include the tyrosine-kinase inhibitors, monoclonal antibody against vascular endothelial growth factor, and inhibitors of the mammalian target of rapamycin. Most recently, the success of immune checkpoint inhibitors--notably antibodies directed against programmed death-1 and its ligand--has also been demonstrated in RCC. With such progress in therapy, early detection, and subsequent management of treatment-related adverse events allow for patients to remain on active therapy for as long as possible and also enhance the probability of patients tolerating subsequent second line options. However, despite such impressive gains in efficacy with these new agents, therapeutic progress are primarily palliative in nature--hence, the critical importance of minimizing discomfort and potential harm in this patient population cannot be understated.

A Phase I Trial of Combined Ridaforolimus and MK-2206 in Patients with Advanced Malignancies

PURPOSE

The PI3K/Akt/mTOR signaling pathway is aberrantly activated in many cancers. Combining ridaforolimus, an mTOR inhibitor, with MK-2206, an Akt inhibitor, may more completely block the PI3K pathway and inhibit tumor growth.

EXPERIMENTAL DESIGN

This phase I study assessed dose-limiting toxicities (DLT) and maximum tolerated dose (MTD) for the combination of oral ridaforolimus plus oral MK-2206 in patients with advanced solid tumors. Efficacy was evaluated in patients with biomarker-identified estrogen receptor-positive breast cancer (low RAS gene signature and high Ki67 index) or castration-resistant prostate cancer (PTEN deficiency) with PI3K pathway addiction.

RESULTS

Thirty-five patients were enrolled: 11 patients in part A (three breast cancer) and 24 biomarker-eligible patients in part B (16 breast cancer, eight prostate cancer). One patient with breast cancer from part A was also found to be biomarker-eligible when tested after she had clinical response. The MTD was 10 mg/d ridaforolimus 5 d/wk + 90 mg/wk MK-2206; 1 of 17 patients experienced DLT (grade 3 rash) at this dose. The most common adverse events at MTD were rash (44.4%), stomatitis (38.9%), diarrhea (27.8%), and decreased appetite (27.8%). By investigator assessment, 2 of 16 (12.5%) evaluable patients with breast cancer had partial response; by central assessment, 2 of 14 (14.3%) evaluable patients had complete response. Two patients had durable stable disease (SD) for 416 and 285 days, respectively. No patients with prostate cancer responded; one patient had SD for ≥ 6 months.

CONCLUSIONS

Combination ridaforolimus and MK-2206 showed promising activity and good tolerability in heavily pretreated patients with hormone-positive and -negative breast cancer exhibiting PI3K pathway dependence.

Cutaneous adverse effects of targeted therapies: Part II: Inhibitors of intracellular molecular signaling pathways

The last decade has spawned an exciting new era of oncotherapy in dermatology, including the development of targeted therapies for metastatic melanoma and basal cell carcinoma. Along with skin cancer, deregulation of the PI3K-AKT-mTOR and RAS-RAF-MEK-ERK intracellular signaling pathways contributes to tumorigenesis of a multitude of other cancers, and inhibitors of these pathways are being actively studied. Similar to other classes of targeted therapies, cutaneous adverse effects are among the most frequent toxicities observed with mitogen-activated protein kinase pathway inhibitors, PI3K-AKT-mTOR inhibitors, hedgehog signaling pathway inhibitors, and immunotherapies. Given the rapid expansion of these families of targeted treatments, dermatologists will be essential in offering dermatologic supportive care measures to cancer patients being treated with these agents. Part II of this continuing medical education article reviews skin-related adverse sequelae, including the frequency of occurrence and the implications associated with on- and off-target cutaneous toxicities of inhibitors of the RAS-RAF-MEK-ERK pathway, PI3K-AKT-mTOR pathway, hedgehog signaling pathway, and immunotherapies.

mTOR inhibitor-associated stomatitis (mIAS) in three patients with cancer treated with everolimus

Mammalian targets of rapamycin inhibitors (mTOR inhibitors, mTORI) are indicated for the management of several cancer types, including hormone receptor--positive or HER2-negative breast cancer, advanced renal cell carcinoma, advanced neuroendocrine tumors of pancreatic origin, and tuberous sclerosis complex-related tumors. Among the most common adverse events of mTORI medication are discrete, large, solitary or multiple, superficial ulcers, almost exclusively situated on nonkeratinized oral mucosa, described as mTORI-associated stomatitis (mIAS). We describe the clinical presentation, course, and management of mIAS in three patients receiving the mTORI everolimus (Afinitor, Novartis, East Hanover, NJ). In two patients, mIAS manifested 9 and 30 days after first using everolimus, respectively, whereas in the third patient, it recurred 3 months after re-introduction of everolimus. Oral rinses with a "magic mouthwash" solution (dexamethasone oral drops solution 2 mg/mL × 10 mL, lidocaine gel 2% × 30 g, doxycycline suspension 50 mg/5 mL × 60 mL, and sucralfate oral suspension 1000 mg/5 mL × 150 mL, dissolved in sodium chloride 0.9% × 2000 mL) four times daily proved helpful in alleviating the symptoms, and the ulcers healed in 4 to 15 days. No side effects were recorded, and dose reduction or discontinuation of everolimus was not necessitated in two cases.

Immunosuppressive and anti-inflammatory properties of engineered nanomaterials

Nanoparticle interactions with various components of the immune system are determined by their physicochemical properties such as size, charge, hydrophobicity and shape. Nanoparticles can be engineered to either specifically target the immune system or to avoid immune recognition. Nevertheless, identifying their unintended impacts on the immune system and understanding the mechanisms of such accidental effects are essential for establishing a nanoparticle's safety profile. While immunostimulatory properties have been reviewed before, little attention in the literature has been given to immunosuppressive and anti-inflammatory properties. The purpose of this review is to fill this gap. We will discuss intended immunosuppression achieved by either nanoparticle engineering, or the use of nanoparticles to carry immunosuppressive or anti-inflammatory drugs. We will also review unintended immunosuppressive properties of nanoparticles per se and consider how such properties could be either beneficial or adverse.

A Prospective Randomised Paired Trial of Sirolimus versus Tacrolimus as Primary Immunosuppression following Non-Heart Beating Donor Kidney Transplantation

INTRODUCTION

With calcineurin inhibitors potentiating damage from ischaemia-reperfusion injury in kidneys from donors after cardiac death we wanted to investigate the role of substituting sirolimus for tacrolimus in the delayed introduction of calcineurin inhibitor regime used in our centre.

METHOD

A prospective randomised paired open-label study was performed taking pairs of kidneys from each donor and randomising one to a tacrolimus-based regime and the other to a similar regime based on sirolimus. Graft function at one year was the primary endpoint.

RESULTS

Total 31 pairs of kidneys were randomised to each group, with 19 pairs of recipients available for analysis after post-randomisation study exclusions. Despite a higher incidence of biopsy proven acute rejection in the sirolimus group, renal allograft function was similar in both groups at three-monthly intervals up to one year post-transplant. All episodes of acute rejection in the sirolimus group occurred in the first three months. Graft and patient survival at one year was 100% in the tacrolimus group, with one death with functioning graft in the sirolimus group (95% survival). Unfortunately, 10 of the 19 patients in the sirolimus arm required switch of medication to tacrolimus due to acute rejection or intolerable drug side effects.

CONCLUSIONS

Graft survival and function were very similar in the two groups despite the higher rate of acute rejection in the sirolimus arm, raising the possibility that the damage done by acute rejection was adequately offset by the nephron-sparing effect of sirolimus compared to tacrolimus. Sirolimus may have a role as a longer-term maintenance immunosuppressant after initial treatment with a different agent such as tacrolimus or belatacept.

Strategies for the management of adverse events associated with mTOR inhibitors

Mammalian target of rapamycin (mTOR) inhibitors are used as potent immunosuppressive agents in solid-organ transplant recipients (everolimus and sirolimus) and as antineoplastic therapies for various cancers (eg, advanced renal cell carcinoma; everolimus, temsirolimus, ridaforolimus). Relevant literature, obtained from specific PubMed searches, was reviewed to evaluate the incidence and mechanistic features of specific adverse events (AEs) associated with mTOR inhibitor treatment, and to present strategies to effectively manage these events. The AEs examined in this review include stomatitis and other cutaneous AEs, wound-healing complications (eg, lymphocele, incisional hernia), diabetes/hyperglycemia, dyslipidemia, proteinuria, nephrotoxicity, delayed graft function, pneumonitis, anemia, hypertension, gonadal dysfunction, and ovarian toxicity. Strategies for selecting appropriate patients for mTOR inhibitor therapy and minimizing the risks of AEs are discussed, along with best practices for identifying and managing side effects. mTOR inhibitors are promising therapeutic options in immunosuppression and oncology; most AEs can be effectively detected and managed or reversed with careful monitoring and appropriate interventions.

Mammalian target of rapamycin inhibitor-associated stomatitis

With the recent introduction of inhibitors of mammalian target of rapamycin (mTOR) in oncology, distinct cutaneous and oral adverse events have been identified. In fact, stomatitis and rash are documented as the most frequent and potentially dose-limiting side effects. Clinically, mTOR inhibitor-associated stomatitis (mIAS) more closely resembles aphthous stomatitis than oral mucositis due to conventional anticancer therapies. While most cases of mIAS are mild to moderate and self-limiting, more severe and persistent mIAS can become a dose-limiting toxicity. Small ulcerations may cause significant pain and mucosal sensitivity may occur in the absence of clinical changes. Use of clinical assessment tools that are primarily driven by ulceration size may underestimate mIAS, and assessment should include patient-reported outcomes. This article provides an up-to-date review of the clinical presentation, terminology, pathogenesis, assessment and management of mIAS and other mTOR inhibitor-associated oral adverse events. In addition, areas of future research are considered.

Everolimus-induced human keratinocytes toxicity is mediated by STAT3 inhibition

Background

Mammalian target of rapamycin (mTOR) inhibitors are associated with dermatological adverse events. The chief aim of this study was to examine the relation between the signal transducer and activator of transcription 3 (STAT3) protein and the dermatological adverse events associated with the mTOR inhibitor everolimus.

Methods

We evaluated the effects of STAT3 activity and related signal transduction activities on everolimus-induced cell growth inhibition in the human keratinocyte HaCaT cell line via a WST-8 assay, and on signal transduction mechanisms involved in everolimus treatments via a western blot analysis. Apoptosis was evaluated using an imaging cytometric assay.

Results

The cell growth inhibitory effects of everolimus were enhanced by stattic or STA-21, which are selective inhibitors of STAT3, treatment in HaCaT cells, although such effects were not observed in Caki-1 and HepG2 cells. Phosphorylation at tyrosine 705 of STAT3 was decreased by treatment with everolimus in a dose-dependent manner in HaCaT cells; in contrast, phosphorylation at serine 727 was not decreased by everolimus, but slightly increased. Furthermore, we found that pretreatment of p38 MAPK inhibitor and transfection with constitutively active form of STAT3 in HaCaT cells resisted the cytostatic activity of everolimus.

Conclusions

These findings suggest that STAT3 activity may be a biomarker of everolimus-induced dermatological toxicity.

Mucocutaneous disorders in renal transplant recipients receiving sirolimus-based immunosuppressive therapy: a prospective, case-control study

BACKGROUND

Sirolimus (SRL) has some dermatologic complications including acneiform eruptions, edema, aphthous ulceration, and onychopathy. However, controlled studies reporting the prevalence and clinical characteristics of mucocutaneous disorders are scarce.

OBJECTIVE

To investigate the prevalence and clinical spectrum of mucocutaneous disorders in renal transplant recipients (RTRs) receiving SRL and to compare the findings with those in RTRs not receiving SRL.

METHODS

Fifty RTRs (35 men, 15 women; mean age, 34.6 ± 11.6 yr) receiving SRL, 50 RTRs (36 men, 14 women; mean age, 34.4 ± 11.3 yr) not on SRL were screened for mucocutaneous disorders.

RESULTS

In RTRs receiving SRL, skin infection (78%) was the most common dermatologic disorder followed by facial hyperpigmentation (50%) and acneiform eruption (46%). Herpes simplex virus infections (14%) and seborrheic dermatitis (38%) were significantly more common in RTRs on SRL (p < 0.05); the frequencies of edema, aphthous ulceration, acne, and longitudinal nail ridging were similar in both groups (p > 0.05).

LIMITATIONS

This study had a small sample size. The investigator was not blinded to immunosuppressive treatment protocols.

CONCLUSION

Renal transplant recipients receiving SRL are more likely to develop seborrheic dermatitis and herpes simplex virus infections than those not taking SRL. Whereas, they are not more prone to edema, aphthous ulceration, acne, or longitudinal nail ridging.

Everolimus: side effect profile and management of toxicities in breast cancer

Everolimus is an orally available inhibitor of the mammalian target of rapamycin (mTOR), which has been approved in combination with exemestane for hormone receptor-positive (HR) breast cancer after failure of treatment with non-steroidal aromatase inhibitors. Everolimus is generally very well tolerated with most common side effects including stomatitis, rash, fatigue, hyperglycemia, hyperlipidemia, and myelosuppression. Most of these side effects are mild and resolve with dose interruptions or dose reductions. Symptomatic non-infectious pneumonitis is a relatively uncommon class effect of mTOR inhibitors, which can be life threatening. Given the efficacy of everolimus in HR-positive metastatic breast cancer, it is crucial for physicians to recognize toxicities related to everolimus and start timely interventions. This review will focus on the adverse events reported with everolimus in breast cancer trials and will provide practical guidelines for the management of these adverse events.

A rapamycin-binding protein polymer nanoparticle shows potent therapeutic activity in suppressing autoimmune dacryoadenitis in a mouse model of Sjögren's syndrome

Sjögren's syndrome (SjS) is a chronic autoimmune disease characterized initially by lymphocytic infiltration and destruction of exocrine glands, followed by systemic organ damage and B-cell lymphoma. Conventional treatment is based on management of symptoms and there is a shortage of therapies that address the underlying causes of inflammation at source exocrine tissue. The aim of this study was to test a novel protein polymer-based platform consisting of diblock copolymers composed from Elastin-like Polypeptides (ELPs) fused with FKBP12, to deliver a potent immunosuppressant with dose-limiting toxicity, rapamycin (Rapa) also known as Sirolimus, and evaluate its effects on the inflamed lacrimal gland (LG) of non-obese diabetic mouse (NOD), a classic mouse model of SjS. Both soluble and diblock copolymer ELPs were fused to FKBP12 and characterized with respect to purity, hydrodynamic radii, drug entrapment and release. Both formulations showed successful association with Rapa; however, the nanoparticle formulation, FSI, released drug with nearly a 5 fold longer terminal half-life of 62.5h. The strong interaction of FSI nanoparticles with Rapa was confirmed in vivo by a shift in the monoexponential pharmacokinetic profile for free drug to a biexponential profile for the nanoparticle formulation. When acutely administered by injection into NOD mice via the tail vein, this FSI formulation significantly suppressed lymphocytic infiltration in the LG relative to the control group while reducing toxicity. There was also a significant effect on inflammatory and mammalian target of Rapamycin (mTOR) pathway genes in the LG and surprisingly, our nanoparticle formulation was significantly better at decreasing a proposed tear biomarker of SjS, cathepsin S (CATS) compared to free drug. These findings suggest that FSI is a promising tool for delivering Rapa for treatment of SjS in a murine model and may be further explored to meet the unmet medical challenge of SjS.

Oral ulcers in patients with advanced breast cancer receiving everolimus: a case series report on clinical presentation and management

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.

Mechanistic target of rapamycin inhibitors in solid organ transplantation: from benchside to clinical use

PURPOSE OF REVIEW

Here, we review recent advances and new insights in mechanistic target of rapamycin (mTOR) biology (signalling pathway, kidney biology and immune system), and recent clinical data on mTOR inhibitors related to solid organ transplantation.

RECENT FINDINGS

The mTOR pathway is a major integrator of signals governing protein and lipid biosynthesis and growth factor-driven cell cycle progression. Recent findings have emphasized a critical role of mTOR in cellular homeostasis with a crucial role in podocyte function. Beyond CD8(+) and regulatory T-cell control, mTOR protein is involved in critical biological functions of T helper cells or dendritic cells. New specific inhibitors of mTORC1/C2 are available and shed new light on mTOR functions. Finally, clinical trials have better defined the use of mTOR inhibitors and emphasized their role in cancer prevention.

SUMMARY

The mTOR pathway is considered as a key integrator of multiple inputs that drives numerous biological processes in cell biology. mTOR inhibitors are potent immunosuppressive drugs for solid organ transplantation. Newly designed specific inhibitors of mTOR complex 1 and 2 offer promising therapeutic effects and a better understanding of the pathway. Many conditions may benefit from mTOR inhibition for a short period, but tolerance of treatment in a chronic setting remains a major concern.

Practical management of everolimus-related toxicities in patients with advanced solid tumors

Everolimus is an orally administered inhibitor of the mammalian target of rapamycin (mTOR), an intracellular protein kinase downstream of the phosphatidylinositol 3-kinase/AKT pathway involved in key components of tumorigenesis, including cell growth, proliferation, and angiogenesis. In the advanced cancer setting, based on favorable results from phase III trials, everolimus is indicated for the treatment of advanced renal cell carcinoma, advanced neuroendocrine tumors of pancreatic origin, and advanced hormone receptor-positive, human epidermal growth factor receptor 2-negative breast cancer. Additional oncology indications for everolimus include renal angiomyolipoma with tuberous sclerosis complex and subependymal giant-cell astrocytoma. Although it is generally well tolerated, with most adverse events of mild to moderate severity and manageable, everolimus exhibits a distinct adverse event profile that warrants guidance for proper diagnostic and medical management. This guidance is particularly important given the potential for widespread long-term use of everolimus. This review will focus on the most relevant toxicities associated with mTOR inhibitors and on their management. Practical treatment recommendations are presented for stomatitis, noninfectious pneumonitis, rash, selected metabolic abnormalities, and infections. Provided these events are rapidly identified and treated, the vast majority should resolve with minimal effect on treatment outcomes and patients' quality of life.

Adverse events associated with mTOR inhibitors

INTRODUCTION

The mTOR (mechanistic target of rapamycin, formerly known as mammalian target of rapamycin) kinase is centrally involved in the regulation of cell growth and metabolism in response to intra- and extracellular energetic stimuli and growth factors. The importance of mTOR in health and diseases has fueled the development of molecules that inhibit mTOR signaling, including rapalogs (sirolimus, temsirolimus, everolimus and deforolimus), which complex with FK506-binding protein 12 (FK-BP12) to inhibit mTOR complex 1 (MTORC1) activity in an allosteric manner, or the more recent ATP-competitive mTOR inhibitors (mTORi), which target the catalytic site of the enzyme. However, clinical development of these mTORi has revealed that these drugs produced numerous side effects that could be serious and/or debilitating. Despite pharmacological efforts to develop drugs with an improved safety profile, these side effects are often unpredictable and may frequently preclude the efficiency of mTORi.

AREAS COVERED

The objective of this review is to perform a comprehensive survey of the safety profiles of various rapalog-based therapies from the available clinical literature. The authors will discuss the potential mechanisms of these therapies, taking into account the knowledge of the biological pathways regulated by mTOR.

EXPERT OPINION

A better prevention and management of mTORi-related side effects requires the identification of alterations in related biological pathways that will help to delineate therapeutic targets.