Standard-dose pembrolizumab in combination with reduced-dose ipilimumab for patients with advanced melanoma (KEYNOTE-029): an open-label, phase 1b trial

Revolutionizing treatment of advanced melanoma with immunotherapy

Until immunotherapy was developed, a diagnosis of metastatic melanoma was most often fatal. Programmed death receptor-1 (PD-1) and cytotoxic T-lymphocyte antigen-4 (CTLA-4) antibodies have been shown to work synergistically to treat metastatic disease throughout the body and brain. Today, over half of patients diagnosed with stage IV disease are alive after 3 years. In the adjuvant setting, 70% patients remain disease free with PD-1 blockade after 1 year. These treatments are generally safe and well tolerated. However, treatment-related endocrinopathies require long-term medications. With better therapies producing more durable responses, advanced cutaneous melanoma is dramatically more manageable now than ever before.

Malignant Melanoma: Diagnostic and Management Update

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Summarize the changes to the American Joint Committee on Cancer Eighth Edition Melanoma Staging System. 2. List advances in genetic, molecular, and histopathologic melanoma diagnosis and prognostication. 3. Recommend sentinel lymph node biopsy and appropriate surgical margins based on individualized patient needs. 4. Recognize the currently available treatments for in-transit metastasis and advanced melanoma. 5. Describe current and future therapies for melanoma with distant visceral or brain metastases.

SUMMARY

Strides in melanoma surveillance, detection, and treatment continue to be made. The American Joint Committee on Cancer Eighth Edition Cancer Staging System has improved risk stratification of patients, introduced new staging categories, and resulted in stage migration of patients with improved outcomes. This review summarizes melanoma advances of the recent years with an emphasis on the surgical advances, including techniques and utility of sentinel node biopsy, controversies in melanoma margin selection, and the survival impact of time-to-treatment metrics. Once a disease manageable only with surgery, a therapeutic paradigm shift has given a more promising outlook to melanoma patients at any stage. Indeed, a myriad of novel, survival-improving immunotherapies have been introduced for metastatic melanoma and more recently in the high-risk adjuvant setting.

Melanom

Das Melanom ist der gefährlichste Hautkrebs mit der höchsten Sterblichkeitsrate, der schon bei jungen Menschen auftreten kann und seit Jahrzehnten steigende Inzidenz verzeichnet (Jemal et al. 2007; Little et al. 2012). Jährlich erkranken weltweit etwa 137.000 Menschen am Melanom und 37.000 versterben an der Erkrankung (Boyle et al. 2004). Die Inzidenz liegt weltweit jährlich bei 2,3–2,6/100.000 Einwohner (Pisani et al. 2002). In Deutschland beträgt die Inzidenz 19,2/100.000 Einwohner und es verstarben 2711 Betroffene im Jahre 2010 (Statistisches Bundesamt).

CTLA4 antagonists in phase I and phase II clinical trials, current status and future perspectives for cancer therapy

INTRODUCTION

In cancer, the immune response to tumor antigens is often suppressed by inhibitors and ligands. Checkpoint blockade, considered one of the most promising frontiers for anti-cancer therapy, aims to stimulate the immune anti-cancer response. Agents such as cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) inhibitors offer prolonged survival with manageable side effects.

AREAS COVERED

We summarize the recent clinical successes of CTLA-4 inhibitors and place a strong emphasis on those in early phase clinical trials, often in combination with other immune check-point inhibitors, i.e., programmed cell death protein 1 (PD-1) and BRAF/mitogen-activated protein kinase inhibitors.

EXPERT OPINION

Recent phase I and phase II clinical trials confirm the efficacy of anti-CTLA-4 therapy for treatment of cancers such as renal cell carcinoma. These studies also indicated increased efficacy with combined immune checkpoint blockade with PD-1 or Ras/Raf/mitogen-activated protein kinase/ERK kinase (MEK)/extracellular-signal-regulated kinase (ERK) inhibitors. Researchers must search for new immune targets that may enable more effective and safe immune checkpoint blockade and cancer therapy. This goal may be achieved by next-generation combination therapies to overcome immune checkpoint therapy resistance.

Delayed immune-related adverse events in assessment for dose-limiting toxicity in early phase immunotherapy trials

BACKGROUND

Immunotherapy (IO) agents can cause late-onset immune-related adverse events (irAEs). In phase I trials, observation for dose-limiting toxicities (DLTs) is typically limited to the first cycle. The incidence of delayed-onset DLTs and their potential impact on dose determination have not been fully elucidated.

PATIENTS AND METHODS

Consecutive patients enrolled in early phase IO trials at Princess Margaret Cancer Centre between August 2012 and September 2016 were retrospectively reviewed, applying trial-specific definitions for DLTs. A clinically significant AE (csAE) was defined as a treatment-related adverse event requiring corticosteroids, hormone replacement, IO delay or discontinuation.

RESULTS

A total of 352 consecutive trial enrolments in 21 early phase clinical trials were included. Two-hundred seventy-eight patients (79%) received monotherapy and 74 (21%) received combination IO. Two hundred sixty (74%) patients experienced irAEs. There were two protocol-defined DLTs. Twenty (5.7%) patients had 24 csAEs qualifying as DLTs except for occurrence after the protocol-specified DLT period. One-hundred and six (10%) of irAEs were csAEs, including endocrine (26%), respiratory (14%), gastrointestinal (11%), general (10%), dermatological (8%), hepatic (8%), musculoskeletal (6%), pancreatic (6%), haematological, metabolic, neurological, cardiac (each 2%), infective and ocular (each 1%) events. The highest risk of first-onset csAE was during the first 4 weeks compared with the period from 4 weeks to end of treatment (odds ratio 3.13, 95% confidence interval 1.95-5.02). The median time to first onset csAE was significantly shorter with combination than monotherapy IO (32 vs. 146 days, P < 0.001).

CONCLUSIONS

In our series of early phase IO trials, the risk of csAE was highest during the initial 4 weeks on IO treatment, supporting the use of the conventional DLT period for dose escalation decision. However, there were 24 clinically significant late-onset DLTs in 5.7% of patients. Combination IO was associated with greater risk of and also earlier onset for csAE, which may need to be considered for early phase trial design.

Role of Anti-PD-1 Antibodies in Advanced Melanoma: The Era of Immunotherapy

Advanced melanoma is an aggressive skin cancer characterized by poor survival rates and response to cytotoxic chemotherapy. Immune checkpoint inhibitors are novel agents capable of utilizing one's own immune system to bring about the tumor destruction. Nivolumab and pembrolizumab are fully humanized anti-PD-1 monoclonal antibodies that have shown significant anti-tumor activity in a variety of cancers including melanoma and have significantly improved the survival outcomes in patients with advanced melanoma. In this updated review article, we will discuss the outcomes of various clinical trials evaluating the efficacy and safety of these agents. We will also briefly discuss their mechanism of action and adverse effects.

Combination Immunotherapy Development in Melanoma

Melanoma has been the most important cancer to drive immunotherapy development of solid tumors. Since 2010, immunotherapy has been revolutionized by the concept of breaking tolerance. It represents a major paradigm shift and marks the beginning of a new era. The impact of the first immune checkpoint inhibitors, anti-CTLA-4 and anti-PD-1/anti-PD-L1, is unprecedented. In 7 years, it transformed advanced-stage melanoma into a curable disease in over 50% of patients. Another major step has been the development of the combination of BRAF inhibitors plus MEK inhibitors in the treatment of BRAF-mutant melanomas. For the treatment of advanced disease, approvals were obtained for the immune checkpoint inhibitors ipilimumab (2011), nivolumab (2014), pembrolizumab (2014), the combination ipilimumab plus nivolumab (2015), and the oncolytic virus vaccine laherparepvec (2015). The combination dabrafenib plus trametinib for BRAF-mutant melanoma was approved in 2014, with similar success for other BRAF plus MEK inhibitor combinations. Because of its unique therapeutic index (high efficacy and low toxicity) anti-PD-1 agents (nivolumab and pembrolizumab) have now been placed at the center of practically all combination therapy development strategies in melanoma. Anti-PD-1 agents are the central molecule for combinations with a great variety of other immunotherapeutics such as immune checkpoint inhibitors, agonists, IDO inhibitors, macrophage polarizing agents, monoclonal antibodies, vaccines, targeted agents, chemotherapeutics, radiation therapy, and even microbiome modulators.

Advanced stage melanoma therapies: Detailing the present and exploring the future

Metastatic melanoma therapies have proliferated over the last ten years. Prior to this, decades passed with only very few drugs available to offer our patients, and even then, those few drugs had minimal survival benefits. Many treatment options emerged over the last ten years with diverse mechanisms of action. Further, combination regimens have demonstrated superiority over monotherapy, especially for targeted agents. Each therapeutic combination possesses different advantages and side effect profiles. In this review, we outline the United States Food and Drug Administration-approved melanoma treatment agents and therapies currently in clinical development, focusing on combination approaches.

Epacadostat Plus Pembrolizumab in Patients With Advanced Solid Tumors: Phase I Results From a Multicenter, Open-Label Phase I/II Trial (ECHO-202/KEYNOTE-037)

PURPOSE

Tumors may evade immunosurveillance through upregulation of the indoleamine 2,3-dioxygenase 1 (IDO1) enzyme. Epacadostat is a potent and highly selective IDO1 enzyme inhibitor. The open-label phase I/II ECHO-202/KEYNOTE-037 trial evaluated epacadostat plus pembrolizumab, a programmed death protein 1 inhibitor, in patients with advanced solid tumors. Phase I results on maximum tolerated dose, safety, tolerability, preliminary antitumor activity, and pharmacokinetics are reported.

PATIENTS AND METHODS

Patients received escalating doses of oral epacadostat (25, 50, 100, or 300 mg) twice per day plus intravenous pembrolizumab 2 mg/kg or 200 mg every 3 weeks. During the safety expansion, patients received epacadostat (50, 100, or 300 mg) twice per day plus pembrolizumab 200 mg every 3 weeks.

RESULTS

Sixty-two patients were enrolled and received one or more doses of study treatment. The maximum tolerated dose of epacadostat in combination with pembrolizumab was not reached. Fifty-two patients (84%) experienced treatment-related adverse events (TRAEs), with fatigue (36%), rash (36%), arthralgia (24%), pruritus (23%), and nausea (21%) occurring in ≥ 20%. Grade 3/4 TRAEs were reported in 24% of patients. Seven patients (11%) discontinued study treatment because of TRAEs. No TRAEs led to death. Epacadostat 100 mg twice per day plus pembrolizumab 200 mg every 3 weeks was recommended for phase II evaluation. Objective responses (per Response Evaluation Criteria in Solid Tumors [RECIST] version 1.1) occurred in 12 (55%) of 22 patients with melanoma and in patients with non-small-cell lung cancer, renal cell carcinoma, endometrial adenocarcinoma, urothelial carcinoma, and squamous cell carcinoma of the head and neck. The pharmacokinetics of epacadostat and pembrolizumab and antidrug antibody rate were comparable to historical controls for monotherapies.

CONCLUSION

Epacadostat in combination with pembrolizumab generally was well tolerated and had encouraging antitumor activity in multiple advanced solid tumors.

Circulating Cytokines Predict Immune-Related Toxicity in Melanoma Patients Receiving Anti-PD-1-Based Immunotherapy

PURPOSE

Combination PD-1 and CTLA-4 inhibitor therapy has dramatically improved the survival of patients with advanced melanoma but is also associated with significant immune-related toxicities. This study sought to identify circulating cytokine biomarkers of treatment response and immune-related toxicity.

EXPERIMENTAL DESIGN

The expression of 65 cytokines was profiled longitudinally in 98 patients with melanoma treated with PD-1 inhibitors, alone or in combination with anti-CTLA-4, and in an independent validation cohort of 49 patients treated with combination anti-PD-1 and anti-CTLA-4. Cytokine expression was correlated with RECIST response and immune-related toxicity, defined as toxicity that warranted permanent discontinuation of treatment and administration of high-dose steroids.

RESULTS

Eleven cytokines were significantly upregulated in patients with severe immune-related toxicities at baseline (PRE) and early during treatment (EDT). The expression of these 11 cytokines was integrated into a single toxicity score, the CYTOX (cytokine toxicity) score, and the predictive utility of this score was confirmed in the discovery and validation cohorts. The AUC for the CYTOX score in the validation cohort was 0.68 at PRE [95% confidence interval (CI), 0.51-0.84; P = 0.037] and 0.70 at EDT (95% CI, 0.55-0.85; P = 0.017) using ROC analysis.

CONCLUSIONS

The CYTOX score is predictive of severe immune-related toxicity in patients with melanoma treated with combination anti-CTLA-4 and anti-PD-1 immunotherapy. This score, which includes proinflammatory cytokines such as IL1a, IL2, and IFNα2, may help in the early management of severe, potentially life-threatening immune-related toxicity.See related commentary by Johnson and Balko, p. 1452.

Emerging Strategies in Systemic Therapy for the Treatment of Melanoma

Recent years have seen major improvements in survival of patients with advanced melanoma with the advent of various novel systemic immunotherapies and targeted therapies. As our understanding of these agents and their various mechanisms of action improves, even more impressive outcomes are being achieved through use of various combination strategies, including the combining of different immunotherapies with one another as well as with other modalities. However, despite the improved outcomes that have been achieved in advanced melanoma, responses to treatment are heterogeneous and may not always be durable. Additional advances in therapy are required, and several emerging strategies are a focus of interest. These include the investigation of several new immunotherapy and/or targeted therapy combinations, such as checkpoint inhibitors (anti-PD-1/anti-CTLA-4) with other immunotherapies (e.g., indoleamine 2,3 dioxygenase [IDO] inhibitors, antilymphocyte activation 3 [anti-LAG-3], histone deacetylase [HDAC] inhibitors, Toll-like receptor 9 [TLR-9] agonists, antiglucocorticoid-induced tumor necrosis factor receptor [anti-GITR], pegylated interleukin-2 [IL-2]), combined targeted therapies (e.g., MEK and CDK4/6 coinhibition), and combined immunotherapy and targeted therapy (e.g., the triplet combination of BRAF/MEK inhibition with anti-PD-1s). The identification of novel therapeutic targets in the MAP kinase pathway also offers opportunities to improve outcomes by overcoming de novo and acquired resistance to BRAF/MEK inhibition (e.g., the development of ERK inhibitors). In addition, adoptive cell transfer, the infusion of large numbers of activated autologous lymphocytes, may have a potential role in patients whose disease has progressed after immunotherapy. Taken together, these new approaches offer further potential to increase systemic treatment options and improve long-term outcomes for patients with advanced melanoma.

Phase Ib/II Study of Pembrolizumab and Pegylated-Interferon Alfa-2b in Advanced Melanoma

PURPOSE

Objective responses are reported in 34% to 37% of patients with programmed death-1 (PD-1)-naïve advanced melanoma treated with PD-1 inhibitors. Pre-existing CD8+ T-cell infiltrate and interferon (IFN) gene signature correlate with response to PD-1 blockade. Here, we report a phase Ib/II study of pembrolizumab/pegylated (PEG)-IFN combination in PD-1-naïve advanced melanoma.

PATIENTS AND METHODS

PEG-IFN (1, 2, and 3 μg/kg per week) was dose escalated using a modified toxicity probability interval design in three cohorts of four patients each, whereas pembrolizumab was dosed at 2 mg/kg every 3 weeks in the phase Ib portion. Thirty-one patients were enrolled in the phase II portion. Primary objectives were safety and incidence of dose-limiting toxicities. Secondary objectives included objective response rate, progression-free survival (PFS), and overall survival.

RESULTS

Forty-three patients with stage IV melanoma were enrolled in the phase Ib and II portions of the study and included in the analysis. At the data cutoff date (December 31, 2017), median follow-up duration was 25 months (range, 1 to 38 months). All 43 patients experienced at least one adverse event; grade 3/4 treatment-related adverse events occurred in 21 of 43 patients (48.8%). Objective responses were seen at all three dose levels among 43 evaluable patients. The objective response rate was 60.5%, with 46.5% of patients exhibiting ongoing response. Median PFS was 11.0 months in all patients and unreached in responders, whereas median overall survival remained unreached in all patients. The 2-year PFS rate was 46%.

CONCLUSION

Pembrolizumab/PEG-IFN demonstrated an acceptable toxicity profile with promising evidence of clinical efficacy in PD-1-naïve metastatic melanoma. These results support the rationale to further investigate this pembrolizumab/PEG-IFN combination in this disease.

Neoadjuvant versus adjuvant ipilimumab plus nivolumab in macroscopic stage III melanoma

Adjuvant ipilimumab (anti-CTLA-4) and nivolumab (anti-PD-1) both improve relapse-free survival of stage III melanoma patients^1,2. In stage IV disease, the combination of ipilimumab + nivolumab is superior to ipilimumab alone and also appears to be more effective than nivolumab monotherapy³. Preclinical work suggests that neoadjuvant application of checkpoint inhibitors may be superior to adjuvant therapy⁴. To address this question and to test feasibility, 20 patients with palpable stage III melanoma were 1:1 randomized to receive ipilimumab 3 mg kg^-1 and nivolumab 1 mg kg^-1, as either four courses after surgery (adjuvant arm) or two courses before surgery and two courses postsurgery (neoadjuvant arm). Neoadjuvant therapy was feasible, with all patients undergoing surgery at the preplanned time point. However in both arms, 9/10 patients experienced one or more grade 3/4 adverse events. Pathological responses were achieved in 7/9 (78%) patients treated in the neoadjuvant arm. None of these patients have relapsed so far (median follow-up, 25.6 months). We found that neoadjuvant ipilimumab + nivolumab expand more tumor-resident T cell clones than adjuvant application. While neoadjuvant therapy appears promising, with the current regimen it induced high toxicity rates; therefore, it needs further investigation to preserve efficacy but reduce toxicity.

Immune-checkpoint inhibitors for combating T-cell dysfunction in cancer

Under normal conditions, the immune system responds effectively to both external and internal threats without damaging healthy tissues. Cells undergoing a neoplastic transformation are one such threat. An efficient activation of T cells is enabled by T-cell receptor (TCR) interactions with antigen-presenting class I and class II molecules of the major histocompatibility complex (MHC), co-stimulatory molecules, and cytokines. After threatening stimuli are removed from the body, the host's immune response ceases, which prevents tissue damage or chronic inflammation. The recognition of foreign antigens is highly selective, which requires multistep regulation to avoid reactions against the antigens of healthy cells. This multistep regulation includes central and peripheral tolerance toward the body's own antigens. Here, we discuss T-cell dysfunction, which leads to poor effector function against foreign antigens, including cancer. We describe selected cellular receptors implicated in T-cell dysfunction and discuss how immune-checkpoint inhibitors can help overcome T-cell dysfunction in cancer treatment.

Current landscape of immunotherapy in the treatment of solid tumours, with future opportunities and challenges

Immunotherapy has emerged as a new standard of care, showing survival benefit for solid tumours in multiple disease sites and indications. The survival improvements seen in diseases that were highly resistant to traditional therapies, with a poor prognosis, are unprecedented. Although the benefits observed in clinical trials are undeniable, not all patients derive those benefits, leading to emerging combination strategies and an ongoing quest for biomarker selection. Here, we summarize the current evidence for immunotherapy in the treatment of solid tumours, and we discuss emerging strategies at the forefront of research. We discuss future challenges that will be encountered as experience and knowledge continue to expand in this rapidly emerging field.

Sentinel Lymph Node Biopsy and Completion Lymph Node Dissection for Melanoma

OPINION STATEMENT

This review critically evaluates recent trials which have challenged the practice of completion lymph node dissection (CLND) for melanoma patients diagnosed with regional metastasis by positive sentinel lymph node biopsy (SLNB). Two trials in the last 2 years, DeCOG-SLT and MSLT-II, found no significant differences in melanoma-specific survival between patients, whether they received immediate CLND or observation after positive SLNB, despite decreases in nodal recurrence achieved by dissection. These trials together disfavor routine CLND in most patients after positive SLNB. However, their conclusions are limited by study populations which overall harbored a lower burden of SLN disease. Special attention needs to be given to patients who do have higher risk disease, with SLN tumor burdens exceeding 1 mm in diameter, for whom CLND may remain both prognostic and therapeutic. Current guidelines thus recommend either CLND or careful observation after positive SLNB after appropriate risk stratification of patients. While a decline in CLND is inevitable, treatment of stage III melanoma is witnessing the concurrent rise of effective adjuvant therapies. PD-1 inhibitors such as nivolumab, or combination BRAF/MEK inhibitors for V600E or K mutant melanoma, which were previously available to only trial patients with completely resected stage III disease, are now approved for use in patients with positive SLNB alone. Providers are better equipped than ever to treat clinically occult, regional metastatic disease with SLNB followed by adjuvant therapy for most patients, but should take steps to avoid undertreatment of high-risk patients who may proceed to disease relapse or progression.

Immuno-Oncology: Emerging Targets and Combination Therapies

Host immunity recognizes and eliminates most early tumor cells, yet immunological checkpoints, exemplified by CTLA-4, PD-1, and PD-L1, pose a significant obstacle to effective antitumor immune responses. T-lymphocyte co-inhibitory pathways influence intensity, inflammation and duration of antitumor immunity. However, tumors and their immunosuppressive microenvironments exploit them to evade immune destruction. Recent PD-1 checkpoint inhibitors yielded unprecedented efficacies and durable responses across advanced-stage melanoma, showcasing potential to replace conventional radiotherapy regimens. Neverthless, many clinical problems remain in terms of efficacy, patient-to-patient variability, and undesirable outcomes and side effects. In this review, we evaluate recent advances in the immuno-oncology field and discuss ways forward. First, we give an overview of current immunotherapy modalities, involving mainy single agents, including inhibitor monoclonal antibodies (mAbs) targeting T-cell checkpoints of PD-1 and CTLA-4. However, neoantigen recognition alone cannot eliminate tumors effectively in vivo given their inherent complex micro-environment, heterogeneous nature and stemness. Then, based mainly upon CTLA-4 and PD-1 checkpoint inhibitors as a "backbone," we cover a range of emerging ("second-generation") therapies incorporating other immunotherapies or non-immune based strategies in synergistic combination. These include targeted therapies such as tyrosine kinase inhibitors, co-stimulatory mAbs, bifunctional agents, epigenetic modulators (such as inhibitors of histone deacetylases or DNA methyltransferase), vaccines, adoptive-T-cell therapy, nanoparticles, oncolytic viruses, and even synthetic "gene circuits." A number of novel immunotherapy co-targets in pre-clinical development are also introduced. The latter include metabolic components, exosomes and ion channels. We discuss in some detail of the personalization of immunotherapy essential for ultimate maximization of clinical outcomes. Finally, we outline possible future technical and conceptual developments including realistic in vitro and in vivo models and inputs from physics, engineering, and artificial intelligence. We conclude that the breadth and quality of immunotherapeutic approaches and the types of cancers that can be treated will increase significantly in the foreseeable future.

Clinical Factors as a Component of the Personalized Treatment Approach to Advanced Pancreatic Cancer: a Systematic Literature Review

INTRODUCTION

Pancreatic cancer is often diagnosed at late stages, where disease is either locally advanced unresectable or metastatic. Despite advances, long-term survival is relatively non-existent.

DISCUSSION

This review article discusses clinical factors commonly encountered in practice that should be incorporated into the decision-making process to optimize patient outcomes, including performance status, nutrition and cachexia, pain, psychological distress, medical comorbidities, advanced age, and treatment selection.

CONCLUSION

Identification and optimization of these clinical factors could make a meaningful impact on the patient's quality of life.

β Cell replacement: improving on the design

PURPOSE OF REVIEW

Here we summarize recent advancements in β cell replacement as a therapy for type 1 diabetes.

RECENT FINDINGS

β cell replacement therapy has been proposed as a cure for type 1 diabetes with the introduction of the Edmonton protocol for cadaveric islet transplantation. To allow widespread use of this approach, efforts have focused on establishing an abundant source of insulin-producing β cells, protecting transplanted cells from ischemia-mediated death, immune rejection, and re-occurring autoimmunity. Recent developments addressing these issues include generation of insulin-producing cells from human pluripotent stem cells, different encapsulation strategies and prevention of ischemia upon transplant.

SUMMARY

Despite significant advances in generating functional β cells from human pluripotent stem cells, several key challenges remain in regard to the survival of β cell grafts, protection from (auto-) immune destruction and implementation of additional safety mechanisms before a stem cell-based cell replacement therapy approach can be widely applied. Taking current findings into consideration, we outline a multilayered approach to design immune-privileged β cells from stem cells using state of the art genome editing technologies that if successfully incorporated could result in great benefit for diabetic patients and improve clinical results for cell replacement therapy.

Expert opinion on thyroid complications in immunotherapy

Thyroid pathologies are the most common forms of endocrinopathy under anticancer immunotherapy. Frequency ranges from 3% to 22% for hypothyroidism and 1% to 11% for thyrotoxicosis. Risk is higher with anti-PD-1 than anti-CTLA-4 treatment and higher again with associated treatment. Pathophysiology mainly consists in silent inflammatory thyroiditis, which accounts for the usual presentation of transient thyrotoxicosis followed by hypothyroidism. Therapeutic strategy usually consists in monitoring with or without symptomatic treatment in case of thyrotoxicosis, and levothyroxine replacement therapy in case of symptomatic hypothyroidism or TSH>10 mIU/L. Screening for dysthyroidism should be systematic ahead of treatment and before each immunotherapy injection for the first 6 months, then at a lower rhythm. It comprises clinical assessment and TSH assay. Onset of thyroid dysfunction should not interrupt immunotherapy, being mainly transient, easy to treat and mild. Teamwork between oncologists and endocrinologists improves screening and management, so as better to accompany the patient during treatment.

A designer self-assembled supramolecule amplifies macrophage immune responses against aggressive cancer

Effectively activating macrophages that can ‘eat’ cancer cells is challenging. In particular, cancer cells secrete macrophage colony stimulating factor (MCSF), which polarizes tumour-associated macrophages from an antitumour M1 phenotype to a pro-tumourigenic M2 phenotype. Also, cancer cells can express CD47, an ‘eat me not’ signal that ligates with the signal regulatory protein alpha (SIRPα) receptor on macrophages to prevent phagocytosis. Here, we show that a supramolecular assembly consisting of amphiphiles inhibiting the colony stimulating factor 1 receptor (CSF-1R) and displaying SIRPα-blocking antibodies with a drug-to-antibody ratio of 17,000 can disable both mechanisms. The supramolecule homes onto SIRPα on macrophages, blocking the CD47-SIRPα signalling axis while sustainedly inhibiting CSF-1R. The supramolecule enhances the M2-to-M1 repolarization within the tumour microenvironment, and significantly improves antitumour and antimetastatic efficacies in two aggressive animal models of melanoma and breast cancer, with respect to clinically available small-molecule and biologic inhibitors of CSF-1R signalling. Simultaneously blocking the CD47-SIRPα and MCSF-CSF-1R signalling axes may constitute a promising immunotherapy.

Immune checkpoint blockade therapy for cancer: An overview of FDA-approved immune checkpoint inhibitors

Although T lymphocytes have long been appreciated for their role in the immunosurveillance of cancer, it has been the realization that cancer cells may ultimately escape a response from tumor-reactive T cells that has ignited efforts to enhance the efficacy of anti-tumor immune responses. Recent advances in our understanding of T cell immunobiology have been particularly instrumental in informing therapeutic strategies to overcome mechanisms of tumor immune escape, and immune checkpoint blockade has emerged as one of the most promising therapeutic options for patients in the history of cancer treatment. Designed to interfere with inhibitory pathways that naturally constrain T cell reactivity, immune checkpoint blockade releases inherent limits on the activation and maintenance of T cell effector function. In the context of cancer, where negative T cell regulatory pathways are often overactive, immune checkpoint blockade has proven to be an effective strategy for enhancing the effector activity and clinical impact of anti-tumor T cells. Checkpoint inhibitors targeting CTLA-4, PD-1, and PD-L1 have yielded unprecedented and durable responses in a significant percentage of cancer patients in recent years, leading to U.S. FDA approval of six checkpoint inhibitors for numerous cancer indications since 2011. In this review, we highlight the clinical success of these FDA-approved immune checkpoint inhibitors and discuss current challenges and future strategies that must be considered going forward to maximize the efficacy of immune checkpoint blockade therapy for cancer.

Real world experience in low-dose ipilimumab in combination with PD-1 blockade in advanced melanoma patients

Dual immune-checkpoint blockade with the anti-PD-1 antibody nivolumab (1 mg/kg) and standard-dose ipilimumab (3 mg/kg) is the mainstay of immunotherapy in advanced melanoma and it is approved since 2016. However, severe side effects (grade 3/4) occur in up to 60% of the patients. Recently, clinical trials have shown similar anti-tumor activity with a more favorable toxicity profile in patients treated with low-dose ipilimumab (1 mg/kg) and standard-dose pembrolizumab (2 mg/kg). In this study we report on the real-world experience of this dosing regime in advanced melanoma patients not eligible for clinical trials. A total of 33 patients with metastatic melanoma (24 with cutaneous and 9 with uveal melanoma) were assessed, retrospectively. Brain metastases were present in 33% of the patients and lactate dehydrogenase was elevated in 70%. Overall response rates were 38% and 0% in cutaneous melanoma and uveal melanoma respectively. Median overall survival was not reached in cutaneous melanoma and was 18 months in uveal melanoma. In 18% of the patients at least one treatment-related severe adverse event was observed. Our observation that the combination of standard dose pembrolizumab and low-dose ipilimumab has a favorable toxicity profile yet anti-tumor activity comparable to the approved standard-dose combination regime in advanced patients not suitable for enrollment in clinical trials is encouraging.

Advanced Melanoma: Current Treatment Options, Biomarkers, and Future Perspectives

Malignant melanoma accounts for the highest number of deaths from skin cancer, and the prognosis of patients with stage IV disease has historically been poor. Novel insights into both mutations driving tumorigenesis and immune escape mechanisms of these tumors have led to effective treatment options that have revolutionized the treatment of this disease. Targeting the MAPK kinase pathway (with BRAF and MEK inhibitors), as well as targeting checkpoints, such as cytotoxic T-lymphocyte associated protein 4 (CTLA-4) or programmed death 1 (PD-1), have improved overall survival in patients with late-stage melanoma, and biomarker research for personalized therapy is ongoing for each of these treatment modalities. In this review, we will discuss current first-line treatment options, discuss biomarkers supporting treatment decisions, and give an outlook on (combination) therapies we expect to become relevant in the near future.

Current landscape and future of dual anti-CTLA4 and PD-1/PD-L1 blockade immunotherapy in cancer; lessons learned from clinical trials with melanoma and non-small cell lung cancer (NSCLC)

Immunotherapy is among the most rapidly evolving treatment strategies in oncology. The therapeutic potential of immune-checkpoint inhibitors is exemplified by the recent hail of Food and Drug Administration (FDA) approvals for their use in various malignancies. Continued efforts to enhance outcomes with immunotherapy agents have led to the formulation of advanced treatment strategies. Recent evidence from pre-clinical studies evaluating immune-checkpoint inhibitors in various cancer cell-lines has suggested that combinatorial approaches may have superior survival outcomes compared to single-agent immunotherapy regimens. Preliminary trials assessing combination therapy with anti-PD-1/PD-L1 plus anti-CTLA-4 immune-checkpoint inhibitors have documented considerable advantages in survival indices over single-agent immunotherapy. The therapeutic potential of combinatorial approaches is highlighted by the recent FDA approval of nivolumab plus ipilimumab for patients with advanced melanoma. Presently, dual-immune checkpoint inhibition with anti-programmed death receptor-1/programmed cell death receptor- ligand-1 (anti-PD-1/PD-L1) plus anti-cytotoxic T lymphocyte associated antigen-4 (anti-CTLA-4) monoclonal antibodies (MoAbs) is being evaluated for a wide range of tumor histologies. Furthermore, several ongoing clinical trials are investigating combination checkpoint inhibition in association with traditional treatment modalities such as chemotherapy, surgery, and radiation. In this review, we summarize the current landscape of combination therapy with anti-PD-1/PD-L1 plus anti-CTLA-4 MoAbs for patients with melanoma and non-small cell lung cancer (NSCLC). We present a synopsis of the prospects for expanding the indications of dual immune-checkpoint inhibition therapy to a more diverse set of tumor histologies.

Trial Watch: Immunostimulation with recombinant cytokines for cancer therapy

Cytokines regulate virtually aspects of innate and adaptive immunity, including the initiation, execution and extinction of tumor-targeting immune responses. Over the past three decades, the possibility of using recombinant cytokines as a means to elicit or boost clinically relevant anticancer immune responses has attracted considerable attention. However, only three cytokines have been approved so far by the US Food and Drug Administration and the European Medicines Agency for use in cancer patients, namely, recombinant interleukin (IL)-2 and two variants of recombinant interferon alpha 2 (IFN-α2a and IFN-α2b). Moreover, the use of these cytokines in the clinics is steadily decreasing, mostly as a consequence of: (1) the elevated pleiotropism of IL-2, IFN-α2a and IFN-α2b, resulting in multiple unwarranted effects; and (2) the development of highly effective immunostimulatory therapeutics, such as immune checkpoint blockers. Despite this and other obstacles, research in the field continues as alternative cytokines with restricted effects on specific cell populations are being evaluated. Here, we summarize research preclinical and clinical developments on the use of recombinant cytokines for immunostimulation in cancer patients.

Pembrolizumab Plus Pegylated Interferon alfa-2b or Ipilimumab for Advanced Melanoma or Renal Cell Carcinoma: Dose-Finding Results from the Phase Ib KEYNOTE-029 Study

Purpose: Pembrolizumab monotherapy, ipilimumab monotherapy, and pegylated interferon alfa-2b (PEG-IFN) monotherapy are active against melanoma and renal cell carcinoma (RCC). We explored the safety and preliminary antitumor activity of pembrolizumab combined with either ipilimumab or PEG-IFN in patients with advanced melanoma or RCC.Experimental Design: The phase Ib KEYNOTE-029 study (ClinicalTrials.gov, NCT02089685) included independent pembrolizumab plus reduced-dose ipilimumab and pembrolizumab plus PEG-IFN cohorts. Pembrolizumab 2 mg/kg every 3 weeks (Q3W) plus 4 doses of ipilimumab 1 mg/kg Q3W was tolerable if ≤6 of 18 patients experienced a dose-limiting toxicity (DLT). The target DLT rate for pembrolizumab 2 mg/kg Q3W plus PEG-IFN was 30%, with a maximum of 14 patients per dose level. Response was assessed per RECIST v1.1 by central review.Results: The ipilimumab cohort enrolled 22 patients, including 19 evaluable for DLTs. Six patients experienced ≥1 DLT. Grade 3 to 4 treatment-related adverse events occurred in 13 (59%) patients. Responses occurred in 5 of 12 (42%) patients with melanoma and 3 of 10 (30%) patients with RCC. In the PEG-IFN cohort, DLTs occurred in 2 of 14 (14%) patients treated at dose level 1 (PEG-IFN 1 μg/kg/week) and 2 of 3 (67%) patients treated at dose level 2 (PEG-IFN 2 μg/kg/week). Grade 3 to 4 treatment-related adverse events occurred in 10 of 17 (59%) patients. Responses occurred in 1 of 5 (20%) patients with melanoma and 2 of 12 (17%) patients with RCC.Conclusions: Pembrolizumab 2 mg/kg Q3W plus ipilimumab 1 mg/kg Q3W was tolerable and provided promising antitumor activity in patients with advanced melanoma or RCC. The maximum tolerated dose of pembrolizumab plus PEG-IFN had limited antitumor activity in this population. Clin Cancer Res; 24(8); 1805-15. ©2018 AACR.

Immune Toxicity with Checkpoint Inhibition for Metastatic Melanoma: Case Series and Clinical Management

Immune checkpoint inhibitors (anti-PD-1 and anti-CTLA-4 antibodies) are a standard of care for advanced melanoma. Novel toxicities comprise immune-related adverse events (irAE). With increasing use, irAE require recognition, practical management strategies, and multidisciplinary care. We retrospectively evaluated the incidence, kinetics, and management of irAE in 41 patients receiving anti-PD-1 antibody therapy (pembrolizumab) for advanced melanoma. 63% received prior anti-CTLA-4 antibody therapy (ipilimumab). IrAE occurred in 54%, most commonly dermatological (24%), rheumatological (22%), and thyroid dysfunction (12%). Thyroiditis was characterised by a brief asymptomatic hyperthyroid phase followed by a symptomatic hypothyroid phase requiring thyroxine replacement. Transplant rejection doses of methylprednisolone were necessary to manage refractory hepatotoxicity. A bullous pemphigoid-like skin reaction with refractory pruritus responded to corticosteroids and neuropathic analgesia. Disabling grade 3-4 oligoarthritis required sulfasalazine therapy in combination with steroids. The median interval between the last dose of anti-CTLA-4 antibody and the first dose of anti-PD-1 therapy was 2.0 months (range: 0.4 to 22.4). Toxicities may occur late; this requires vigilance and multidisciplinary management which may allow effective anticancer therapy to continue. Management algorithms for thyroiditis, hypophysitis, arthralgia/arthritis, colitis, steroid-refractory hepatitis, and skin toxicity are discussed.

Immunotherapy for Melanoma

While melanoma is less common than some other skin cancers, it is responsible for nearly 10,000 deaths in the USA each year alone. For many decades, very limited treatment options were available for patients with metastatic melanoma. However, recent breakthroughs have brought new hopes for patients and providers.While targeted therapy with BRAF and MEK inhibitors represents an important cornerstone in the treatment of metastatic melanoma, this chapter carefully reviews the past and current therapy options available, with a significant focus on immunotherapy-based approaches. In addition, we provide an overview of the results of recent advances in the adjuvant setting for patients with resected stage III and stage IV melanoma, as well as in patients with melanoma brain metastases. Finally, we provide a quick overview over the current research efforts in the field of immuno-oncology and melanoma.

Safety of resuming anti-PD-1 in patients with immune-related adverse events (irAEs) during combined anti-CTLA-4 and anti-PD1 in metastatic melanoma

Background

Combined cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed death 1 (PD-1) blockade induces high rates of immune-related adverse events (irAEs). The safety of resuming anti-PD-1 in patients who discontinue combination therapy due to irAEs is not known.

Patients and methods

We assessed patients who experienced clinically significant irAEs from combined CTLA-4 and PD-1 blockade leading to treatment discontinuation at four academic centers. We assessed the safety of resuming anti-PD-1 in terms of recurrent and distinct irAEs.

Results

Eighty patients discontinued combination therapy due to irAEs, including colitis (41%), hepatitis (36%), and pneumonitis (4%). Of these, 96% received corticosteroids and 21% received additional immunosuppression (e.g. infliximab). All were rechallenged with anti-PD-1, and 14 (18%) had recurrent irAEs at a median of 14 days after therapy resumption (six grade 1-2, seven grade 3-4, and one grade 5 Steven-Johnson Syndrome). Colitis was less likely to recur than other irAEs (6% versus 28%, P = 0.01). Clinically significant but distinct toxicities occurred in an additional 17 (21%) patients (11 grade 1-2 and 6 grade 3-4). Duration of steroid taper, severity of initial irAEs and use of additional immunosuppressants did not predict for toxicity on rechallenge, although patients remaining on steroid therapy at anti-PD-1 resumption had higher rates of toxicities (55% versus 31%, P = 0.03).

Conclusions

Patients who discontinued CTLA-4/PD-1 blockade for severe irAEs had relatively high rates of recurrent or distinct toxicities with anti-PD-1 resumption. However, many patients, particularly with combination-induced colitis, tolerated anti-PD-1 rechallenge well, and this approach can be considered in selected patients.

The 2017 complete overhaul of adjuvant therapies for high-risk melanoma and its consequences for staging and management of melanoma patients

The spectacular outcomes of the phase III trials regarding nivolumab versus ipilimumab in fully resected stage IIIB/C-IV and of the combination of dabrafenib (D) plus trametinib (T) in BRAF-mutant stage III patients demonstrate that effective treatments in advanced melanoma are also highly effective in the adjuvant setting. In 2016, an overall survival benefit with adjuvant high-dose ipilimumab was demonstrated, and the European Organisation for Research and Treatment of Cancer trial 1325 comparing pembrolizumab versus placebo will complete the picture in the early 2018. Toxicity profiles are in line with the experience in advanced melanoma, i.e. favourable for the anti-PD1 agents and for D + T and problematic for ipilimumab. The 2017 outcomes are practice changing and put an end to the use of interferon (IFN) and ipilimumab. In countries with only access to IFN, its use can be restricted to patients with ulcerated melanoma, based on the individual patient data meta-analysis recently published. Because of the results of the Melanoma Sentinel Lymph node Trial-2 (MSLT-2) trial, completion lymph node dissection (CLND) will decrease sharply, leading to a lack of optimal prognostic information. Prognosis in sentinel node-positive stage IIIA/B patients is extremely heterogeneous with 5-year survival rates varying from 90% to 40% and depends mostly on the number of positive nodes identified by CLND. This information is crucial for clinical decision-making. How to guarantee optimal staging information needs to be discussed urgently. Further improvements of adjuvant therapies will have to address all these questions as well as the exploration of neoadjuvant use of active drugs and combination approaches. Important paradigm shifts in the management of high-risk melanoma patients are upon us.