Anti-CTLA-4 antibody therapy associated autoimmune hypophysitis: serious immune related adverse events across a spectrum of cancer subtypes

Immune checkpoint inhibitor therapy associated hypophysitis

Ipilimumab is a monoclonal antibody directed against CTLA4 T-lymphocyte antigen used as cancer therapy. Immune-related adverse events are common side effects and may include hypophysitis-related hypopituitarism. The clinical features of six patients with ipilimumab-induced hypophysitis (IH) are described. The clinical features of IH reported in clinical trials, including the incidence of IH by gender and the likelihood of adrenal axis recovery, are summarized. Following the development of IH, most patients remain on glucocorticoid replacement despite efforts to withdraw therapy. Analysis of gender information in published clinical trials suggests that men are more prone to developing IH than women, and few patients fully recover the pituitary–adrenal axis function. Ipilimumab and other drugs within its class are likely to be used to treat many forms of cancer. Endocrinologists should anticipate a significant increase in the incidence of autoimmune hypophysitis. Strategies for early detection of IH and long-term management should be considered.

Blockade of CTLA-4 promotes the development of effector CD8+ T lymphocytes and the therapeutic effect of vaccination with an attenuated protozoan expressing NY-ESO-1

The development of cancer immunotherapy has long been a challenge. Here, we report that prophylactic vaccination with a highly attenuated Trypanosoma cruzi strain expressing NY-ESO-1 (CL-14-NY-ESO-1) induces both effector memory and effector CD8(+) T lymphocytes that efficiently prevent tumor development. However, the therapeutic effect of such a vaccine is limited. We also demonstrate that blockade of Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) during vaccination enhances the frequency of NY-ESO-1-specific effector CD8(+) T cells producing IFN-γ and promotes lymphocyte migration to the tumor infiltrate. As a result, therapy with CL-14-NY-ESO-1 together with anti-CTLA-4 is highly effective in controlling the development of an established melanoma.

Review of immune-related adverse events in prostate cancer patients treated with ipilimumab: MD Anderson experience

Targeting a T cell inhibitory checkpoint with the anti-CTLA-4 monoclonal antibody, ipilimumab, represents a scientific breakthrough in immunotherapy for the treatment of cancer. However, ipilimumab therapy is also associated with unique side effects, known as immune-related adverse events (irAEs), which need to be recognized and managed with immunosuppressive agents. To date, the majority of our knowledge regarding ipilimumab-associated side effects is based upon clinical studies in melanoma. Here, we provide a review of ipilimumab-induced irAEs and our experience in a cohort of 44 patients with prostate cancer who were treated at M. D. Anderson Cancer Center on two different clinical trial protocols.

Long-term follow-up of ipilimumab-induced hypophysitis, a common adverse event of the anti-CTLA-4 antibody in melanoma

OBJECTIVE

Few data are published on the long-term follow-up of ipilimumab-induced hypophysitis, a cytotoxic T-lymphocyte antigen 4 antibody. We characterized hypophysitis in terms of clinical signs, endocrinological profile, and imaging at diagnosis and during a long-term follow-up.

DESIGN AND PATIENTS

Fifteen patients, treated for malignant melanoma and who presented ipilimumab-induced hypophysitis, were observed between June 2006 and August 2012 in Timone Hospital, Marseille.

METHODS

Symptoms, pituitary function, and pituitary imaging at diagnosis of hypophysitis and during the follow-up were recorded.

RESULTS

Of 131 patients treated with ipilimumab or a placebo, 15 patients (10 mg/kg in 11/15) presented with hypophysitis (≥11.5%) at 9.5±5.9 weeks (mean±s.d.) after treatment start, occurring in 66% after the third infusion. The main initial symptoms were headache (n=13) and asthenia (n=11). All patients but one had at least one hormonal defect: thyrotroph (n=13), gonadotroph (n=12), or corticotroph (n=11) deficiencies. None had diabetes insipidus. Pituitary imaging showed a moderately enlarged gland in 12 patients. Clinical symptoms improved rapidly on high-dose glucocorticoids (n=11) or physiological replacement doses (n=4). At the end of follow-up (median 33.6 months, range 7-53.5), corticotroph deficiency remained in 13 patients, 11 recovered thyrotroph and ten gonadotroph functions. Pituitary imaging remained abnormal in 11 patients.

CONCLUSION

Ipilimumab-induced hypophysitis is a common side-effect with frequent hormonal deficiencies at diagnosis. Usually, hormonal deficiencies improved, except for corticotroph function. Patients receiving these immunomodulatory therapies should be closely monitored especially by systematic baseline hormone measurements after the third infusion and remain at a risk of adrenal insufficiency in the long-term.

A novel melanoma therapy stirs up a storm: ipilimumab-induced thyrotoxicosis

Ipilimumab, a novel therapy for metastatic melanoma, inhibits cytotoxic T-lymphocyte apoptosis, causing both antitumor activity and significant autoimmunity, including autoimmune thyroiditis. Steroids are frequently used in treatment of immune-related adverse events; however, a concern regarding the property of steroids to reduce therapeutic antitumor response exists. This study describes the first reported case of ipilimumab-associated thyroid storm and implicates iopanoic acid as an alternative therapy for immune-mediated adverse effects. An 88-year-old woman with metastatic melanoma presented with fatigue, anorexia, decreased functional status, and intermittent diarrhea for several months, shortly after initiation of ipilimumab – a recombinant human monoclonal antibody to the cytotoxic T-lymphocyte-associated antigen 4 (CTLA4). On arrival, she was febrile, tachycardic, and hypertensive with a wide pulse pressure, yet non-toxic appearing. She had diffuse, non-tender thyromegaly. An electrocardiogram (EKG) revealed supraventricular tachycardia. Blood, urine, and stool cultures were collected, and empiric antibiotics were started. A computed tomography (CT) angiogram of the chest was negative for pulmonary embolism or pneumonia, but confirmed a diffusely enlarged thyroid gland, which prompted thyroid function testing. TSH was decreased at 0.16 μIU/ml (normal 0.3–4.7); free tri-iodothyronine (T₃) was markedly elevated at 1031 pg/dl (normal 249–405), as was free thyroxine (T₄) at 5.6 ng/dl (normal 0.8–1.6). With iopanoic acid and methimazole therapy, she markedly improved within 48 h, which could be attributed to lowering of serum T₃ with iopanoic acid rather than to any effect of the methimazole. Ipilimumab is a cause of overt thyrotoxicosis and its immune-mediated adverse effects can be treated with iopanoic acid, a potent inhibitor of T₄-to-T₃ conversion.

Anticytotoxic T-lymphocyte antigen-4 induced autoimmune hypophysitis: a case report and literature review

Objective. We describe a case of autoimmune hypophysitis induced by the anticytotoxic T-lymphocyte antigen-4 (CTLA-4) agent, ipilimumab. Methods. Case presentation and review of the literature. Results. Autoimmune hypophysitis, a previously described rare disorder, is being recognized more frequently as a side effect of novel immunomodulatory agents used in the treatment of malignancies such as melanoma. CTLA-4 agents are associated with immune-related adverse effects (irAE) which occur as a result of activation (or lack of inactivation) of the immune response. This impacts not only malignant cells but also different host organ-systems. Autoimmune hypophysitis is one of several endocrinopathies associated with these agents. Conclusion. It is important that endocrinologists become familiar with the endocrinopathies, such as autoimmune hypophysitis, associated with new immunomodulator agents which are being used with increasing frequency to treat a variety of malignancies.

Immune Checkpoint Blockade in Cancer Therapy

Immunologic checkpoint blockade with antibodies that target cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death protein 1 pathway (PD-1/PD-L1) have demonstrated promise in a variety of malignancies. Ipilimumab (CTLA-4) and pembrolizumab (PD-1) are approved by the US Food and Drug Administration for the treatment of advanced melanoma, and additional regulatory approvals are expected across the oncologic spectrum for a variety of other agents that target these pathways. Treatment with both CTLA-4 and PD-1/PD-L1 blockade is associated with a unique pattern of adverse events called immune-related adverse events, and occasionally, unusual kinetics of tumor response are seen. Combination approaches involving CTLA-4 and PD-1/PD-L1 blockade are being investigated to determine whether they enhance the efficacy of either approach alone. Principles learned during the development of CTLA-4 and PD-1/PD-L1 approaches will likely be used as new immunologic checkpoint blocking antibodies begin clinical investigation.

Systemic high-dose corticosteroid treatment does not improve the outcome of ipilimumab-related hypophysitis: a retrospective cohort study

PURPOSE

To examine the onset and outcome of ipilimumab-related hypophysitis and the response to treatment with systemic high-dose corticosteroids (HDS).

EXPERIMENTAL DESIGN

Twenty-five patients who developed ipilimumab-related hypophysitis were analyzed for the incidence, time to onset, time to resolution, frequency of resolution, and the effect of systemic HDS on clinical outcome. To calculate the incidence, the total number (187) of patients with metastatic melanoma treated with ipilimumab at Dana-Farber Cancer Institute (DFCI; Boston, MA) was retrieved from the DFCI oncology database. Comparisons between corticosteroid treatment groups were performed using the Fisher exact test. The distributions of overall survival were based on the method of Kaplan-Meier.

RESULTS

The overall incidence of ipilimumab-related hypophysitis was 13%, with a higher rate in males (16.1%) than females (8.7%). The median time to onset of hypophysitis after initiation of ipilimumab treatment was 9 weeks (range, 5-36 weeks). Resolution of pituitary enlargement, secondary adrenal insufficiency, secondary hypothyroidism, male secondary hypogonadism, and hyponatremia occurred in 73%, 0%, 64%, 45%, and 92% of patients, respectively. Systemic HDS treatment did not improve the outcome of hypophysitis as measured by resolution frequency and time to resolution. One-year overall survival in the cohort of patients was 83%, and while it was slightly higher in patients who did not receive HDS, there was no statistically significant difference between treatment arms.

CONCLUSION

Systemic HDS therapy in patients with ipilimumab-related hypophysitis may not be indicated. Instead, supportive treatment of hypophysitis-related hormone deficiencies with the corresponding hormone replacement should be given.

The development of immunomodulatory monoclonal antibodies as a new therapeutic modality for cancer: the Bristol-Myers Squibb experience

The discovery and increased understanding of the complex interactions regulating the immune system have contributed to the pharmacologic activation of antitumor immunity. The activity of effector cells, such as T and NK cells, is regulated by an array of activating and attenuating receptors and ligands. Agents that target these molecules can modulate immune responses by exerting antagonistic or agonistic effects. Several T- or NK-cell modulators have entered clinical trials, and two have been approved for use. Ipilimumab (Yervoy®, Bristol-Myers Squibb) and nivolumab (OPDIVO, Ono Pharmaceutical Co., Ltd./Bristol-Myers Squibb) were approved for the treatment of metastatic melanoma, in March 2011 in the United States, and in July 2014 in Japan, respectively. The clinical activity of these two antibodies has not been limited to tumor types considered sensitive to immunotherapy, and promising activity has been reported in other solid and hematologic tumors. Clinical development of ipilimumab and nivolumab has presented unique challenges in terms of safety and efficacy, requiring the establishment of new evaluation criteria for adverse events and antitumor effects. Guidelines intended to help oncologists properly manage treatment in view of these non-traditional features have been implemented. The introduction of this new modality of cancer treatment, which is meant to integrate with or replace the current standards of care, requires additional efforts in terms of optimization of treatment administration, identification of biomarkers and application of new clinical trial designs. The availability of immune modulators with different mechanisms of action offers the opportunity to establish immunological combinations as new standards of care.

Pituitary expression of CTLA-4 mediates hypophysitis secondary to administration of CTLA-4 blocking antibody

Hypophysitis is a chronic inflammation of the pituitary gland of unknown (primary forms) or recognizable (secondary forms) etiology, such as the use of ipilimumab in cancer immunotherapy. Ipilimumab, which blocks the T cell inhibitory molecule CTLA-4 (cytotoxic T lymphocyte antigen-4), induces hypophysitis in about 4% of patients through unknown mechanisms. We first established a model of secondary hypophysitis by repeated injections of a CTLA-4 blocking antibody into SJL/J or C57BL/6J mice, and showed that they developed lymphocytic infiltration of the pituitary gland and circulating pituitary antibodies. We next assessed the prevalence of pituitary antibodies in a cohort of 20 patients with advanced melanoma or prostate cancer, 7 with a clinical diagnosis of hypophysitis, before and after ipilimumab administration. Pituitary antibodies, negative at baseline, developed in the 7 patients with hypophysitis but not in the 13 without it; these antibodies predominantly recognized thyrotropin-, follicle-stimulating hormone-, and corticotropin-secreting cells. We then hypothesized that the injected CTLA-4 antibody could cause pituitary toxicity if bound to CTLA-4 antigen expressed "ectopically" on pituitary endocrine cells. Pituitary glands indeed expressed CTLA-4 at both RNA and protein levels, particularly in a subset of prolactin- and thyrotropin-secreting cells. Notably, these cells became the site of complement activation, featuring deposition of C3d and C4d components and an inflammatory cascade akin to that seen in type II hypersensitivity. In summary, the study offers a mechanism to explain the pituitary toxicity observed in patients receiving ipilimumab, and highlights the utility of measuring pituitary antibodies in this form of secondary hypophysitis.

Pituitary side effects of old and new drugs

INTRODUCTION

Pituitary function is influenced by several drugs, including anti-depressant, opioids, glucocorticoids, chemotherapeutic agents, immunomodulators and the newly developed tyrosine kinase inhibitors. In most instances, treatment with these drugs negatively affects pituitary function, but in rare cases an activation of specific hypothalamic-pituitary axes may be observed. Several of the observed pituitary side effects are reversible after drug withdrawal, but pituitary function deficiency may persist long-term. In addition to the well known drugs, recent evidence shows that also non-steroidal anti-inflammatory drugs impair gonadal axis at pituitary level, while antipsychotic phenothiazines alter TSH response to TRH and TSH levels. Atypical antipsychotics may decrease TRH-stimulated TSH. Tricyclic antidepressant drugs interfere with the hypothalamo-pituitary-thyroid axis by decreasing TSH response to TRH. Anabolic-androgenic steroids, marijuana, cocaine, methamphetamines, and opioid narcotics negatively impact fertility, also acting at hypothalamic-pituitary level.

CONCLUSIONS

Many of the drugs administered routinely in the intensive care unit significantly impact the hypothalamic-pituitary axis. Therefore, an increased awareness on pituitary side effects of drugs commonly used in clinical practice is necessary in order to rule out possible pharmacological interference when assessing patients with pituitary deficiencies.

Thyroid-like ophthalmopathy in a euthyroid patient receiving Ipilimumab

A 68-year-old lady with metastatic malignant melanoma was treated with Ipilimumab. She presented to Eye Casualty unable to move her eyes. Physical examination confirmed ophthalmoplegia and identified proptosis bilaterally. Radiological imaging showed bilateral enlargement of all the extra-ocular muscles suggestive of thyroid eye disease. Laboratory investigations found this patient to be euthyroid. A diagnosis of thyroid-like orbitopathy secondary to Ipilimumab therapy was made. Thyroid function tests should be performed for all patients prior to their commencement of Ipilimumab. Thyroid-like eye disease may develop in patients treated with Ipilimumab even if they remain euthyroid.

Ipilimumab treatment associated pituitary hypophysitis: clinical presentation and imaging diagnosis

Ipilimumab is an immunomodulating drug for use in treatment of unresectable or metastatic melanoma with autoimmune lymphocytic hypophysitis as a reported complication. We describe three recent cases of ipilimumab associated autoimmune hypophysitis (IAH) at our institution, and provide a selected literature review showing its variable clinical presentation, imaging appearance and treatment in order to expedite early and appropriate IAH management. Patients had variable clinical presentation of hypophysitis, including headache, fatigue, visual changes, endocrinopathy, and/or hyponatremia. Contrast enhanced MRI showed symmetric pituitary gland and stalk enlargement in all of our cases and received a presumptive diagnosis of IAH. Following cessation of therapy and treatment there was normalization of pituitary morphology at follow-up MRI and return to clinical baseline. Varying clinical presentation can complicate the diagnosis of lymphocytic hypophysitis. One must be cognizant of its overall clinical and radiologic picture in patients receiving ipilimumab, now commonly used for the treatment of metastatic melanoma.

Humanized mice as a model for aberrant responses in human T cell immunotherapy

Immune-deficient mice, reconstituted with human stem cells, have been used to analyze human immune responses in vivo. Although they have been used to study immune responses to xenografts, allografts, and pathogens, there have not been models of autoimmune disease in which the mechanisms of the pathologic process can be analyzed. We have found that reconstituted "humanized" mice treated with anti-CTLA-4 Ab (ipilimumab) develop autoimmune disease characterized by hepatitis, adrenalitis, sialitis, anti-nuclear Abs, and weight loss. Induction of autoimmunity involved activation of T cells and cytokine production, and increased infiltration of APCs. When anti-CTLA-4 mAb-treated mice were cotreated with anti-CD3 mAb (teplizumab), hepatitis and anti-nuclear Abs were no longer seen and weight loss did not occur. The anti-CD3 blocked proliferation and activation of T cells, release of IFN-γ and TNF, macrophage infiltration, and release of IP-10 that was induced with anti-CTLA-4 mAb. We also found increased levels of T regulatory cells (CD25(+)CD127(-)) in the spleen and mesenteric lymph nodes in the mice treated with both Abs and greater constitutive phosphorylation of STAT5 in T regulatory cells in spleen cells compared with mice treated with anti-CTLA-4 mAb alone. We describe a model of human autoimmune disease in vivo. Humanized mice may be useful for understanding the mechanisms of biologics that are used in patients. Hepatitis, lymphadenopathy, and other inflammatory sequelae are adverse effects of ipilimumab treatment in humans, and this study may provide insights into this pathogenesis and the effects of immunologics on autoimmunity.

Endocrine-related adverse events following ipilimumab in patients with advanced melanoma: a comprehensive retrospective review from a single institution

Novel immune checkpoint blockade with ipilimumab, an antibody blocking the cytotoxic T-lymphocyte antigen 4 (CTLA4), is revolutionizing cancer therapy. However, ipilimumab induces symptomatic, sometimes severe, endocrine immune-related adverse events (irAEs) that are inconsistently recognized and reported. The objective of this review was to comprehensively characterize the incidence, presentation, and management of endocrinopathies following ipilimumab therapy in a single center that is highly specialized in immune checkpoint blockade. We carried out a retrospective analysis of endocrine irAEs in melanoma patients receiving ipilimumab therapy in clinical trials between 2007 and 2013. A total of 256 patients were included in this analysis. We reviewed pituitary-, thyroid-, and adrenal-related hormone test results, as well as radiographic studies and the clinical histories of patients, to identify and characterize cases of hypophysitis, hypothyroidism, thyroiditis, and adrenal dysfunction. Following ipilimumab therapy, the overall incidence of hypophysitis was 8% and that of hypothyroidism/thyroiditis 6%. Primary adrenal dysfunction was rare. Therapy with a combination of ipilimumab and nivolumab, an anti-programmed cell death 1 (PDCD1, also called PD1) receptor antibody, was associated with a 22% incidence of either thyroiditis or hypothyroidism and a 9% incidence of hypophysitis. Symptomatic relief, in particular, for hypophysitis, was achieved in all patients with hormone replacement, although endogenous hormone secretion rarely recovered. In summary, we observed that CTLA4 blockade alone, and in particular in combination with PD1 blockade, is associated with an increased risk of symptomatic, sometimes severe, hypophysitis as well as thyroid dysfunction. Prompt initiation with hormone replacement reverses symptoms. Evaluation and reporting of endocrine irAEs in clinical trials should be done using standardized diagnostic criteria and terminology.

Ipilimumab in the treatment of metastatic melanoma: management of adverse events

Recently, "ipilimumab," an anti-cytotoxic T-lymphocyte antigen-4 (CTLA-4) monoclonal antibody, has been demonstrated to improve overall survival in metastatic melanoma. "CTLA-4" is an immune-checkpoint molecule that downregulates pathways of T-cell activation. Ipilimumab, by targeting CTLA-4, is able to remove the CTLA-4 inhibitory signal, allowing the immune system to react to cancer cells. Due to its immune-based mechanism of action, ipilimumab causes the inhibition of CTLA-4-mediated immunomodulatory effects, the enhancement of antitumor specific immune response mediated by the weakening of self-tolerance mechanisms while exacerbating the development of autoimmune diseases and immune-related adverse events, including dermatitis, hepatitis, enterocolitis, hypophysitis, and uveitis.

Ocular side effects of biological agents in oncology: what should the clinician be aware of?

During the last 20 years, biologicals have become increasingly relevant in oncologic therapy. Depending on the medication used, there are different profiles of ocular side effects. Although these can be present in up to 70% of patients, they are generally underreported in the literature. Therefore, the pathophysiological details of their development are often poorly understood. Herein we attempt to identify groups of biologicals to which a specific side effect profile can be assigned. We also tried to capture all relevant side effects and therefore conducted several database investigation including Medline, Cochrane library, and the drugs section of the US Food and Drug Administration (FDA), using the following search strings: “name of biological agent (both generic and commercial names)” AND “eye” OR “ocular”. If we found a side effect that has been associated with a drug, we researched Medline using the following search string: “name of biological agent” (both generic and commercial names) AND “term for the specific side effect”. Due to the wealth of material we report only the drugs that are approved by the FDA.

Endocrine side-effects of anti-cancer drugs: mAbs and pituitary dysfunction: clinical evidence and pathogenic hypotheses

mAbs are established targeted therapies for several diseases, including hematological and solid malignancies. These agents have shown a favorable toxicity profile, but, despite their high selectivity, new typical side-effects have emerged. In cancer patients, pituitary dysfunction may be mainly due to brain metastases or primary tumors and to related surgery and radiotherapy. Anticancer agents may induce hypopituitarism in patients cured for childhood cancers. These agents infrequently affect pituitary function in adult cancer patients. Notably, hypophysitis, a previously very rare disease, has emerged as a distinctive side-effect of ipilimumab and tremelimumab, two mAbs inhibiting the cytotoxic T-lymphocyte antigen-4 receptor, being occasionally seen with nivolumab, another immune checkpoint inhibitor. Enhanced antitumor immunity is the suggested mechanism of action of these drugs and autoimmunity the presumptive mechanism of their toxicity. Recently, ipilimumab has been licensed for the treatment of patients affected by metastatic melanoma. With the expanding use of these drugs, hypophysitis will be progressively encountered by oncologists and endocrinologists in clinical practice. The optimal management of this potentially life-threatening adverse event needs a rapid and timely diagnostic and therapeutic intervention. Hypopituitarism caused by these agents is rarely reversible, requiring prolonged or lifelong substitutive hormonal treatment. Further studies are needed to clarify several clinical and pathogenic aspects of this new form of secondary pituitary dysfunction.

Ipilimumab and its toxicities: a multidisciplinary approach

The treatment for metastatic melanoma has evolved significantly in the past few years. Ipilimumab, an immunotherapy, is now in mainstream oncology practice given that it has shown improved overall survival in randomized clinical trials. Other immune modulating agents, such as programmed death receptor-1 and programmed death receptor ligand-1 antibodies, are showing promise in early clinical trials. This manuscript will review ipilimumab and its most common side effects. Immune-related adverse events (irAEs) are important to recognize early, and their presentation, timing of onset, and general recommendations for workup and management will be reviewed. Assembling a multidisciplinary team, as well as thorough education of the patient, is recommended to optimize patient care.

At the bedside: CTLA-4- and PD-1-blocking antibodies in cancer immunotherapy

It is increasingly appreciated that cancers are recognized by the immune system, and under some circumstances, the immune system may control or even eliminate tumors. The modulation of signaling via coinhibitory or costimulatory receptors expressed on T cells has proven to be a potent way to amplify antitumor immune responses. This approach has been exploited successfully for the generation of a new class of anticancer therapies, "checkpoint-blocking" antibodies, exemplified by the recently FDA-approved agent, ipilimumab, an antibody that blocks the coinhibitory receptor CTLA-4. Capitalizing on the success of ipilimumab, agents that target a second coinhibitory receptor, PD-1, or its ligand, PD-L1, are in clinical development. Lessons learned from treating patients with CTLA-4 and PD-1 pathway-blocking antibodies will be reviewed, with a focus on concepts likely to inform the clinical development and application of agents in earlier stages of development. See related review At the bench: Preclinical rationale for CTLA-4 and PD-1 blockade as cancer immunotherapy.

Endocrine side effects induced by immune checkpoint inhibitors

CONTEXT

In recent years, progress has been made in cancer immunotherapy by the development of drugs acting as modulators of immune checkpoint proteins, such as the cytotoxic T-lymphocyte antigen-4 (CTLA4) and programmed death-1 (PD-1), two co-inhibitory receptors that are expressed on T cells upon activation. These molecules play crucial roles in maintaining immune homeostasis by down-regulating T-cell signaling, thereby preventing unbridled T-cell proliferation while maintaining tolerance to self-antigens, such as tumor-associated antigens. CTLA4 blockade through systemic administration of the CTLA4-blocking antibody ipilimumab was shown to confer significant survival benefit and prolonged stable disease in patients affected by advanced cutaneous melanoma. Other immune checkpoint inhibitors are under clinical evaluation. However, immune checkpoint blockade can lead to the breaking of immune self-tolerance, thereby inducing a novel syndrome of autoimmune/autoinflammatory side effects, designated as "immune-related adverse events," mainly including rash, colitis, hepatitis, and endocrinopathies.

DATA ACQUISITION

We searched the medical literature using the words "hypophysitis," "hypopituitarism," "thyroid," "adrenal insufficiency," and "endocrine adverse events" in association with "immune checkpoint inhibitors," "ipilimumab," "tremelimumab," "PD-1," and "PD-1-L."

EVIDENCE SYNTHESIS

The spectrum of endocrine disease experienced by patients treated with ipilimumab includes most commonly hypophysitis, more rarely thyroid disease or abnormalities in thyroid function tests, and occasionally primary adrenal insufficiency. Hypophysitis has emerged as a distinctive side effect of CTLA4-blocking antibodies, establishing a new form of autoimmune pituitary disease. This condition, if not promptly recognized, may be life-threatening (due to secondary hypoadrenalism). Hypopituitarism caused by these agents is rarely reversible, and prolonged or lifelong substitutive hormonal treatment is often required. The precise mechanism of injury to the endocrine system triggered by these drugs is yet to be fully elucidated.

CONCLUSIONS

Although reports of endocrine side effects caused by cancer immune therapy are abundant, their exact prevalence and mechanism are unclear. Well-designed correlative studies oriented to finding and validating predictive factors of autoimmune toxicity are urgently needed.

The unfolding treatment landscape for men with castration-resistant prostate cancer

Castration-resistant prostate cancer (CRPC) is a fatal disease in virtually all patients. Docetaxel chemotherapy became the standard front-line agent based on the results of the TAX327 trial in 2004, with a survival advantage of 3 months achieved over mitoxantrone. Over the past few years, an improved understanding of the molecular biology of castration-resistance has resulted in expansion of the treatment armamentarium for advanced prostate cancer with the emergence of novel androgen receptor-directed therapies, cytotoxic chemotherapies, as well as immunotherapies. Four different agents have very recently gained approval by the U.S. Food and Drug Administration for the treatment of CRPC and this review will summarize the development, mechanism of action, and safety and efficacy of these agents as demonstrated in preclinical as well as clinical studies.

[Hypophysitis: increasingly complex clinicopathological spectrum!]

Hypophysitis is a chronic inflammation of the pituitary gland that comprises an increasingly complex clinicopathological spectrum. Lymphocytic and granulomatous hypophysitis are the most common forms, but new variants have recently been reported such as IgG4-related hypophysitis that is identified by well-defined criteria. For the first time, hypophysitis in ANCA-associated vasculitides has been reported. Monoclonal antibodies directed against the cytotoxic T-lymphocyte antigen-4 (CTLA-4), investigated in metastatic melanoma, can induce hypophysitis. Hypophysitis's pathogenesis remains obscure but several candidate pituitary autoantigens have been described in the last decade, although none has proven useful as a diagnostic tool.

Radiotherapy-induced hypopituitarism: a review

Hypopituitarism is a disorder caused by impaired hormonal secretions from the hypothalamic-pituitary axis. Radiotherapy is the most common cause of iatrogenic hypopituitarism. The hypothalamic-pituitary axis inadvertently gets irradiated in patients receiving prophylactic cranial radiotherapy for leukemia, total body irradiation and radiotherapy for intracranial, base skull, sinonasal and nasopharyngeal tumors. Radiation-induced hypopituitarism (RIH) is insidious, progressive and largely nonreversible. Mostly, RIH involves one hypothalamic-pituitary axis; however, multiple hormonal axes deficiency starts developing at higher doses. Although the clinical effects of the hypopituitarism are more profound in children and young adults, its implications in older adults are being increasingly recognized. The risk continues to persist or increase up to 10 years following radiation exposure. The clinical management of hypopituitarism is challenging both for the patients and healthcare providers. Here we have reviewed the scale of the problem, the risk factors and the management of RIH.

Association of ipilimumab therapy for advanced melanoma with secondary adrenal insufficiency: a case series

OBJECTIVE

To present a case series of ipilimumab-related secondary adrenal insufficiency.

METHODS

In this cases series, we review the presentation, evaluation, diagnosis, and management of patients with advanced melanoma who received ipilimumab and were referred to our endocrinology clinic for evaluation of hormonal abnormalities.

RESULTS

Seven patients presented with symptoms, signs, or biochemical evidence of adrenal insufficiency 6 to 12 weeks after starting ipilimumab therapy. Ipilimumab is a cytotoxic T-lymphocyte antigen 4 (CTLA-4) monoclonal antibody that is approved for the treatment of metastatic melanoma and has widespread use for this disease. All 7 patients had biochemical evidence of profound secondary adrenal insufficiency. Thyroid function abnormalities, central hypogonadism, and low insulinlike growth factor 1 levels were seen in a subset of patients. Only 2 patients had abnormal findings on pituitary magnetic resonance imaging. Posterior pituitary function remained normal.

CONCLUSIONS

Our findings suggest that the enhanced immune response associated with ipilimumab therapy may have a predilection for corticotroph and possibly thyrotroph cells. We recommend periodic hypothalamic-pituitary-adrenal axis monitoring for patients on this therapy.

Ipilimumab: its potential in non-small cell lung cancer

Ipilimumab is a fully human monoclonal antibody that enhances antitumor immunity by way of cytotoxic T-lymphocyte antigen 4 blockade. It has already been approved by the US Food and Drug Administration for the treatment of metastatic melanoma and is being investigated for treating other solid tumors such as renal cell, prostate and lung cancers. This review details the potential of ipilimumab in the management of non-small cell lung cancer (NSCLC). In particular, ipilimumab showed promising results in a first-line NSCLC phase II study combining carboplatin/paclitaxel chemotherapy with concurrent or phased ipilimumab. The median immune-related progression-free survival was 5.68 months for the phased ipilimumab arm versus 4.63 months for chemotherapy alone (hazard ratio [HR] = 0.68, p = 0.026) and 5.52 months for the concurrent ipilimumab arm versus 4.63 months for chemotherapy alone (HR = 0.77, p = 0.094). The main adverse events were immune related, such as hypophysitis, enterocolitis, and hyperthyroidism. These adverse events may be improved with high-dose glucocorticoids and may be correlated with tumor response. Phase III studies are ongoing. Future studies may investigate ipilimumab in the management of early stage lung cancer. Strategies for potential translational research studies are also discussed to identify prognostic and predictive biomarkers for the use of ipilimumab in the treatment of patients with NSCLC.

Update on the diagnosis and management of hypophysitis

PURPOSE OF REVIEW

To discuss the multiple forms of hypophysitis, the various methods of classification, the recent findings in pituitary autoimmunity and novel methods of treating resistant or recurrent hypophysitis. (January 2010-December 2011).

RECENT FINDINGS

Multiple novel presentations of hypophysitis have been described including cytotoxic T-lymphocyte antigen-4 antibody-related hypophysitis, an adverse event associated with a novel treatment for cancer, Food and Drug Administration approved for use in the treatment of metastatic melanoma. A rare, but newly described entity of immunoglobulin G4 related plasmacytic hypophysitis has been described and reviewed. Multiple investigations addressing the role of autoimmunity in the diagnosis and pathogenesis of hypophysitis have been reported with positive antipituitary antibodies found in patients with autoimmune hypophysitis, other autoimmune diseases, and nonimmune-related pituitary diseases. Several case series and case reports present new associations with concomitant diseases and novel therapy for cases requiring treatment when standard therapy fails or is contraindicated.

SUMMARY

Hypophysitis is a rare disease with multiple subtypes. The description of hypophysitis related to cytotoxic T-lymphocyte antigen-4 antibody treatment is one of the first descriptions of hypophysitis triggered by medication. As the use of this novel treatment for cancer increases, so must our awareness of immune-related adverse effects and their treatment. Pituitary autoimmunity is a challenging field with multiple discoveries reported to help further our understanding of the disease and assist in diagnosis. Insufficient sensitivity and specificity of the currently reported methods prevents recommending measurement of antipituitary antibodies as standard of care in the diagnosis of hypophysitis. The treatment of hypophysitis remains controversial with recommendations ranging from hormonal replacement to newly described therapies such as azathioprine and radiation.

Ipilimumab: a novel immunomodulating therapy causing autoimmune hypophysitis: a case report and review

Ipilimumab (Yervoy; Medarex and Bristol-Myers Squibb) is a human MAB against cytotoxic T-lymphocyte antigen 4, which enhances co-stimulation of cytotoxic T-lymphocytes, resulting in their proliferation and an anti-tumour response. It is licensed for the treatment of unresectable or metastatic malignant melanoma, while multiple clinical trials using this medication in the treatment of other malignancies are ongoing. As a clinical response to ipilimumab results from immunostimulation, predictably it generates autoimmunity as well, causing immune-related adverse events in the majority of patients. Of those, endocrinopathies are frequently seen, and in particular, autoimmune lymphocytic hypophysitis with anterior panhypopituitarism has been reported a number of times in North America. We present a case of a male referred to our department with manifestations of anterior panhypopituitarism after his third dose of ipilimumab for metastatic malignant melanoma, and we discuss the management of his case in the light of previous reports. We also review the published literature on the presenting symptoms, time to presentation, investigations, imaging, treatment and follow-up of ipilimumab-induced autoimmune lymphocytic hypophysitis.

Hypopituitarism in the elderly

Pituitary dysfunction in elderly can represent a true diagnostic and therapeutic challenge to clinicians caring for these patients. Symptoms associated with partial or total hypopituitarism, such as fatigue, lower muscle strength and decreased libido, are nonspecific and can be often attributed to normal aging. Gold standard pituitary diagnostic testing carries higher risks in elderly and is classically replaced by alternative testing. Furthermore, the benefits and safety of selective pituitary hormonal replacement, specifically sexual and growth hormone replacement, remain subject of controversy in this group of patients. Recognizing and appropriately treating hypopituitarism in elderly is crucial for the survival and well being of the older patients with this disease.

Cutting edge: neuronal recognition by CD8 T cells elicits central diabetes insipidus

An increasing number of neurologic diseases is associated with autoimmunity. The immune effectors contributing to the pathogenesis of such diseases are often unclear. To explore whether self-reactive CD8 T cells could attack CNS neurons in vivo, we generated a mouse model in which the influenza virus hemagglutinin (HA) is expressed specifically in CNS neurons. Transfer of cytotoxic anti-HA CD8 T cells induced an acute but reversible encephalomyelitis in HA-expressing recipient mice. Unexpectedly, diabetes insipidus developed in surviving animals. This robust phenotype was associated with preferential accumulation of cytotoxic CD8 T cells in the hypothalamus, upregulation of MHC class I molecules, and destruction of vasopressin-expressing neurons. IFN-γ production by the pathogenic CD8 T cells was necessary for MHC class I upregulation by hypothalamic neurons and their destruction. This novel mouse model, in combination with related human data, supports the concept that autoreactive CD8 T cells can trigger central diabetes insipidus.

Hypophysitis induced by monoclonal antibodies to cytotoxic T lymphocyte antigen 4: challenges from a new cause of a rare disease

Specific human monoclonal antibodies antagonize cytotoxic T-lymphocyte antigen 4 (anti-CTLA-4 mAbs), a negative regulator of the immune system, inducing unrestrained T-cell activation. In patients with advanced or metastatic melanoma, one of these agents, ipilimumab, produced considerable disease control rates and, for the first time, a clear improvement in overall survival outcomes. However, accumulating clinical experience with anti-CTLA-4 mAbs identified a novel syndrome of autoimmune and autoinflammatory side effects, designated as "immune-related adverse events," including mainly rash, colitis, and hepatitis. Autoimmune hypophysitis has emerged as a distinctive side effect induced by anti-CTLA-4 mAbs. This condition may be life threatening because of adrenal insufficiency if not promptly recognized, but it may easily be diagnosed and treated if clinically suspected. Hypopituitarism caused by these agents is rarely reversible and prolonged or life-long substitutive hormonal treatment is often required. The precise mechanism of injury to the pituitary triggered by anti-CTLA-4 mAbs is yet to be fully elucidated.

A new era for castrate resistant prostate cancer: a treatment review and update

PURPOSE

The purpose of this review article is to present the current treatment options for castrate resistant prostate cancer in addition to the recently approved agents and their role in treatment.

SUMMARY

The biology of prostate cancer and the data supporting the use of traditional chemotherapeutic options in castrate resistant prostate cancer are reviewed. The newly approved agents, sipuleucel-T, cabazitaxel, and abiraterone, are presented as well. The studies that led to the approval of these three agents are discussed in this article as well as their current and potential roles in the treatment of castrate resistant prostate cancer.

CONCLUSION

New mechanisms, drugs, and clinically relevant molecular targets show survival advantage and are new options available for patients after traditional chemotherapy. The roles of these new agents have yet to be further clarified in future studies.

Combined immunotherapy with granulocyte-macrophage colony-stimulating factor-transduced allogeneic prostate cancer cells and ipilimumab in patients with metastatic castration-resistant prostate cancer: a phase 1 dose-escalation trial

BACKGROUND

The granulocyte-macrophage colony-stimulating factor-transduced allogeneic prostate cancer cells vaccine (GVAX) has antitumour activity against prostate cancer; preclinical studies have shown potent synergy when combined with ipilimumab, an antibody that blocks cytotoxic T-lymphocyte antigen 4. We aimed to assess the safety of combined treatment with GVAX and ipilimumab in patients with metastatic castration-resistant prostate cancer (mCRPC).

METHODS

We did an open-labelled, single-centre, dose-escalation study of ipilimumab concurrent with a fixed dose of GVAX, with a subsequent expansion phase, both at the VU University Medical Centre (Amsterdam, Netherlands). Eligible patients had documented mCRPC and had not been previously treated with chemotherapy. All patients received a 5×10(8) cell priming dose of GVAX intradermally on day 1 with subsequent intradermal injections of 3×10(8) cells every 2 weeks for 24 weeks. The vaccinations were combined with intravenous ipilimumab every 4 weeks. We enrolled patients in cohorts of three; each cohort received an escalating dose of ipilimumab at 0·3, 1·0, 3·0, or 5·0 mg/kg. Our primary endpoint was safety. This study is registered with ClinicalTrials.gov, number NCT01510288.

FINDINGS

We enrolled 12 patients into our dose-escalation cohort. We did not record any severe immune-related adverse events at the first two dose levels. At the 3·0 mg/kg dose level, one patient had grade 2 and two patients grade 3 hypophysitis; at the 5·0 mg/kg dose level, two patients had grade 3 hypophysitis and one patient developed grade 4 sarcoid alveolitis (a dose-limiting toxic effect). Due to observed clinical activity and toxic events, we decided to expand the 3·0 mg/kg dose level, rather than enrol a further three patients at the 5·0 mg/kg level. 16 patients were enrolled in the expansion cohort, two of whom developed grade 2 hypophysitis, three colitis (one grade 1 and two grade 2), and one grade 3 hepatitis--all immune-related adverse events. The most common adverse events noted in all 28 patients were injection-site reactions (grade 1-2 events seen in all patients), fatigue (grade 1-2 in 20 patients, grade 3 in two), and pyrexia (grade 1-2 in 15 patients, grade 3 in one). 50% or greater declines in prostate-specific antigen from baseline was recorded in seven patients (25%); all had received 3·0 mg/kg or 5·0 mg/kg ipilimumab.

INTERPRETATION

GVAX combined with 3·0 mg/kg ipilimumab is tolerable and safe for patients with mCRPC. Further research on the combined treatment of patients with mCRPC with vaccination and ipilimumab is warranted.

FUNDING

Cell Genesys Inc, Prostate Cancer Foundation, Dutch Cancer Society (KWF-VU 2006-3697), and Foundation Stichting VUmc Cancer Center Amsterdam.

The monoclonal antibody to cytotoxic T lymphocyte antigen 4, ipilimumab, in the treatment of melanoma

BACKGROUND

Cytotoxic T lymphocyte antigen 4 (CTLA-4) is an inhibitory regulator of the T-cell immune response against tumor cells. Ipilimumab is a monoclonal antibody directed against CTLA-4.

OBJECTIVE

This review describes the basic mechanism of ipilimumab and discusses data available to date with regards to its safety and efficacy profile.

METHODS

Data from clinical trials including abstracts was reviewed using the PubMed Database, as well as the American Society of Clinical Oncology Abstract Database.

CONCLUSION

CTLA-4 inhibition with a monoclonal antibody is usually well tolerated and has efficacy as a therapeutic agent in a variety of cancers. The classical response interpretation has changed because of the delayed mechanism of action. The toxicities are autoimmune events and guidelines for treatment of these effects are discussed. Therapy with ipilimumab leads to durable responses. The first two Phase III randomized studies showed an improvement of survival at 1, 2, and 3 years. Other studies are currently underway to better understand the optimal treatment administration of ipilimumab in melanoma.

Emerging therapeutic approaches in the management of metastatic castration-resistant prostate cancer

Although treatment options for men with castration-resistant prostate cancer (CRPC) have improved with the recent and anticipated approvals of novel immunotherapeutic, hormonal, chemotherapeutic and bone-targeted agents, clinical benefit with these systemic therapies is transient and survival times remain unacceptably short. Thus, we devote the second section of this two-part review to discussing emerging therapeutic paradigms and research strategies that are entering phase II and III clinical testing for men with metastatic CRPC. We will discuss a range of emerging hormonal, immunomodulatory, antiangiogenic, epigenetic and cell survival pathway inhibitors in current clinical trials, with an emphasis on how these therapies may complement our existing treatment options.

Diagnosis and management of pituitary adenomas

PURPOSE OF REVIEW

Pituitary adenomas are frequently encountered in practice either because of clinical symptoms or as incidental findings. These tumors may alter pituitary function and can therefore have a considerable impact on morbidity, mortality, and quality of life.

RECENT FINDINGS

The presentation is variable for each type of tumor, with microadenomas being either silent or manifesting with symptoms of hormonal excess. In contrast, macroadenomas may present with mass effect. The various histologic types include prolactinomas, nonfunctioning adenomas, somatotropinomas, corticotropinomas, and thyrotropinomas. The present article will serve as an update on the diagnosis and treatment of pituitary adenomas. Advances in medical management for each tumor are discussed, highlighting new therapeutic alternatives. The role of surgery is also reviewed. Recommendations on the surveillance and postoperative monitoring of patients are emphasized.

SUMMARY

Newer methods in the diagnosis and treatment for pituitary adenomas greatly expand our ability to care for affected patients.

Ipilimumab: a novel treatment for metastatic melanoma

OBJECTIVE

To review the mechanism of action, pharmacokinetics, efficacy, safety, drug interactions, dosing, and economic considerations of ipilimumab.

DATA SOURCES

A literature search using MEDLINE (1966-November 2010) was performed using the terms ipilimumab, metastatic melanoma, MDX-010, and MDX-101. Additional data were obtained from meeting abstracts, bibliographies, and media releases.

STUDY SELECTION AND DATA EXTRACTION

English-language articles identified from the data sources were reviewed. Selected studies evaluated the pharmacology, pharmacokinetics, efficacy, and safety of ipilimumab for the treatment of metastatic melanoma.

DATA SYNTHESIS

The incidence of melanoma in the US is increasing faster than any other type of cancer in men and more than any other type of cancer, except lung cancer, in women. For patients with metastatic melanoma, systemic therapies are limited by low response rates, short durations of response, and a 5-year survival rate <10%. Ipilimumab, a novel CTLA-4 inhibitor, is under investigation for the treatment of metastatic melanoma. Results of a randomized, controlled Phase 3 trial showed a first-ever overall survival benefit for patients with previously treated metastatic melanoma who received ipilimumab compared with the controls. The majority of adverse events reported with ipilimumab administration are considered to be low-grade immune-related events involving the skin and intestine and can be managed medically. Nonetheless, 10-17% of patients have immune-related adverse events of grade 3 or higher severity, with 2-3% of these events resulting in death.

CONCLUSIONS

Ipilimumab is a novel CTLA-4 inhibitor that has been evaluated for the treatment of metastatic melanoma. On March 25, 2011, the Food and Drug Administration approved ipilimumab, making it the first agent indicated for unresectable or metastatic melanoma in more than a decade.

Thyroid autoimmunity and ophthalmopathy related to melanoma biological therapy

OBJECTIVE

Ipilimumab is a fully human MAB against cytotoxic T-lymphocyte antigen 4 (CTLA4). CTLA4 negatively regulates immune cell activation. In patients with metastatic melanoma, ipilimumab increases survival time and induces complete remission in some patients. However, immune-related adverse events including endocrinopathies have been reported. Bevacizumab, an angiogenesis inhibitor, has been used in combination with ipilimumab in patients with advanced melanoma.

PATIENTS AND METHODS

In this study, we report three patients who received ipilimumab alone or combined with bevacizumab therapy and developed thyroiditis, and the first report of euthyroid Graves' ophthalmopathy.

RESULTS

Case 1 is a 51-year-old female who presented with severe eye pain, proptosis, and periorbital edema. Laboratory results revealed normal TSH, elevated thyroid antibodies but low titer of anti-TSH receptor antibody. Imaging was consistent with Graves' ophthalmopathy. Cases 2 and 3 were referred for hyperthyroidism, and workup revealed thyroiditis. These three cases suggest that patients with advanced melanoma treated with ipilimumab +/- bevacizumab may be susceptible to a variety of thyroid disorders.

CONCLUSIONS

Anti-CTLA4 therapy has shown promising results in treating advanced malignancy such as melanoma and renal carcinoma. A number of endocrinopathies, including thyroid disorders, may develop during ipilimumab therapy. The association of bevacizumab with endocrinopathies is not clear, although a few reports suggest a link to hypothyroidism. All patients on ipilimumab and/or bevacizumab therapy should be monitored for signs or symptoms of thyroiditis.

Hyponatremia associated with Ipilimumab-induced hypophysitis

A 75-year-old woman with a history of stage IV metastatic melanoma underwent treatment with the CTLA-4 blocking agent Ipilimumab. She presented 2 months after initiating treatment with a severe headache. Laboratories were consistent with severe hyponatremia. MRI of the brain revealed enlargement of the pituitary gland, enhancement of the infundibulum, and an enhancing, centrally necrotic foci in the anterior pituitary. Based on the clinical and radiographic findings, she was diagnosed with treatment-related syndrome of inappropriate antidiuretic hormone secretion (SIADH). Effective treatment consisted of fluid restriction, hyperosmolar therapy, and steroids.

Anti-CTLA-4 antibody therapy: immune monitoring during clinical development of a novel immunotherapy

Cytotoxic T-lymphocyte-associated antigen (CTLA-4), also known as CD152, is a co-inhibitory molecule that functions to regulate T-cell activation. Antibodies that block the interaction of CTLA-4 with its ligands B7.1 and B7.2 can enhance immune responses, including antitumor immunity. Two CTLA-4-blocking antibodies are presently under clinical investigation: ipilimumab and tremelimumab. CTLA-4 blockade has shown promise in treatment of patients with metastatic melanoma, with a recently completed randomized, double-blind phase III trial demonstrating a benefit in overall survival (OS) in the treated population. However, this approach appears to benefit only a subset of patients. Understanding the mechanism(s) of action of CTLA-4 blockade and identifying prognostic immunologic correlates of clinical endpoints to monitor are presently areas of intense investigation. Several immunologic endpoints have been proposed to correlate with clinical activity. This review will focus on the endpoints of immune monitoring described in studies to date and discuss future areas of additional work needed.

The emerging toxicity profiles of anti-CTLA-4 antibodies across clinical indications

The promising new class of immunomodulating antibodies directed against cytotoxic T-lymphocyte antigen-4 (CTLA-4) has been extensively tested in clinical trials and found to be active against cutaneous melanoma and other tumor histotypes. Inhibition of CTLA-4 characteristically induces well-identified side effects for which the definition "immune-related adverse events" (irAEs) has been proposed. IrAEs mainly include colitis/diarrhea, dermatitis, hepatitis, and endocrinopathies; uveitis, nephritis, and inflammatory myopathy also have been reported occasionally. These unique side effects are likely a direct result of breaking immune tolerance upon CTLA-4 blockade and are generally mild, reversible, and manageable, following specific treatment guidelines that include symptomatic therapies or systemic corticosteroids. However, patient-physician communication and early treatment are also emerging as critical issues to successfully manage irAEs, thus avoiding major complications. The major experience in identifying and managing CTLA-4 treatment-related side effects has derived from studies in melanoma patients; nevertheless, accumulating clinical experiences are clearly demonstrating that irAEs are class-specific events, and that they are fully overlapping in patients with tumors of different histotypes. This review provides an overview of current safety data on CTLA-4 antagonists and of available strategies to optimize their clinical use in cancer patients.

Update on vaccine development for renal cell cancer

Renal cell carcinoma (RCC) remains a significant health concern that frequently presents as metastatic disease at the time of initial diagnosis. Current first-line therapeutics for the advanced-stage RCC include antiangiogenic drugs that have yielded high rates of objective clinical response; however, these tend to be transient in nature, with many patients becoming refractory to chronic treatment with these agents. Adjuvant immunotherapies remain viable candidates to sustain disease-free and overall patient survival. In particular, vaccines designed to optimize the activation, maintenance, and recruitment of specific immunity within or into the tumor site continue to evolve. Based on the integration of increasingly refined immunomonitoring systems in both translational models and clinical trials, allowing for the improved understanding of treatment mechanism(s) of action, further refined (combinational) vaccine protocols are currently being developed and evaluated. This review provides a brief history of RCC vaccine development, discusses the successes and limitations in such approaches, and provides a rationale for developing combinational vaccine approaches that may provide improved clinical benefits to patients with RCC.

Preoperative CTLA-4 blockade: tolerability and immune monitoring in the setting of a presurgical clinical trial

PURPOSE

Cytotoxic T lymphocyte associated antigen (CTLA-4) blockade is being explored in numerous clinical trials as an immune-based therapy for different malignancies. Our group conducted the first preoperative clinical trial with the anti-CTLA-4 antibody ipilimumab in 12 patients with localized urothelial carcinoma of the bladder.

EXPERIMENTAL DESIGN

Six patients were treated with 3 mg/kg/dose of anti-CTLA-4 and six patients were treated with 10 mg/kg/dose of antibody. Primary end points of the study were safety and immune monitoring.

RESULTS

Most drug-related adverse events consisted of grade 1/2 toxicities. All patients had measurable immunologic pharmacodynamic effects, consisting of an increased frequency of CD4+ICOShi T cells in tumor tissues and the systemic circulation. To determine if CD4+ICOShi T cells could be a correlative marker for clinical outcome after treatment with anti-CTLA-4, a cohort of metastatic melanoma patients was studied retrospectively for frequency of CD4+ICOShi T cells and survival. Data from this small cohort of patients indicated that an increased frequency of CD4+ICOShi T cells, sustained over a period of 12 weeks of therapy, correlates with increased likelihood of clinical benefit consisting of overall survival.

CONCLUSIONS

Our trial shows that anti-CTLA-4 therapy has a tolerable safety profile in the presurgical setting and that a preoperative model can be used to obtain biological data on human immune responses, which can efficiently guide the monitoring of patients treated in the metastatic disease setting.