Antitumor Activity in Melanoma and Anti-Self Responses in a Phase I Trial With the Anti-Cytotoxic T Lymphocyte–Associated Antigen 4 Monoclonal Antibody CP-675,206

Immune checkpoint inhibitors in renal cell carcinoma

The immune system has long been known to play a critical role in the body's defence against cancer, and there have been multiple attempts to harness it for therapeutic gain. Renal cancer was, historically, one of a small number of tumour types where immune manipulation had been shown to be effective. The current generation of immune checkpoint inhibitors are rapidly entering into routine clinical practice in the management of a number of tumour types, including renal cancer, where one drug, nivolumab, an anti-programmed death-1 (PD-1) monoclonal antibody (mAb), is licensed for patients who have progressed on prior systemic treatment. Ongoing trials aim to maximize the benefits that can be gained from this new class of drug by exploring optimal timing in the natural course of the disease as well as combinations with other checkpoint inhibitors and drugs from different classes.

Clinical and immunologic evaluation of three metastatic melanoma patients treated with autologous melanoma-reactive TCR-transduced T cells

Malignant melanoma incidence has been increasing for over 30 years, and despite promising new therapies, metastatic disease remains difficult to treat. We describe preliminary results from a Phase I clinical trial (NCT01586403) of adoptive cell therapy in which three patients received autologous CD4⁺ and CD8⁺ T cells transduced with a lentivirus carrying a tyrosinase-specific TCR and a marker protein, truncated CD34 (CD34t). This unusual MHC Class I-restricted TCR produces functional responses in both CD4⁺ and CD8⁺ T cells. Parameters monitored on transduced T cells included activation (CD25, CD69), inhibitory (PD-1, TIM-3, CTLA-4), costimulatory (OX40), and memory (CCR7) markers. For the clinical trial, T cells were activated, transduced, selected for CD34t⁺ cells, then re-activated, and expanded in IL-2 and IL-15. After lymphodepleting chemotherapy, patients were given transduced T cells and IL-2, and were followed for clinical and biological responses. Transduced T cells were detected in the circulation of three treated patients for the duration of observation (42, 523, and 255 days). Patient 1 tolerated the infusion well but died from progressive disease after 6 weeks. Patient 2 had a partial response by RECIST criteria then progressed. After progressing, Patient 2 was given high-dose IL-2 and subsequently achieved complete remission, coinciding with the development of vitiligo. Patient 3 had a mixed response that did not meet RECIST criteria for a clinical response and developed vitiligo. In two of these three patients, adoptive transfer of tyrosinase-reactive TCR-transduced T cells into metastatic melanoma patients had clinical and/or biological activity without serious adverse events.

Endocrine dysfunction following immune checkpoint inhibitor therapy

PURPOSE OF REVIEW

Immune checkpoint inhibitors (ICI) represent an important milestone in the modern era of antineoplastic therapy and have ushered optimism amongst oncologists and patients alike. These agents, however, are associated with significant potential toxicities, the importance of which cannot be overstated. The clinical presentation, diagnosis, and management strategies of immune-related endocrinopathies associated with ICI use are described in this case-based review.

RECENT FINDINGS

An increasing number of ICI have shown promise in the management of various malignancies in the recent years. These include cytotoxic T lymphocyte antigen-4 inhibitors, programmed cell death 1 (PD-1) antibodies, and PD-ligand 1 (PD-L1) antibodies. Several endocrinopathies, including hypophysitis, thyroid dysfunction, hyperglycemia, and primary adrenal insufficiency, have been associated with the use of these agents. Toxicities may range from mild transient laboratory abnormalities to potentially life-threatening ones, warranting immediate therapeutic intervention. Combination ICI therapies may be associated with a greater risk of endocrine dysfunction when compared with monotherapy. The clinical presentation and laboratory assessment of these patients often pose a diagnostic challenge as they may be confused by the symptoms related to their underlying malignancy or potential associated acute illnesses.

SUMMARY

ICI use is associated with serious endocrinopathies that may have a nonspecific initial presentation. A constant eye for these symptoms and a systematic approach to diagnosis are essential for prompt initiation of therapy and prevention of significant complications.

Targeting T Cell Co-receptors for Cancer Therapy

Checkpoint-blocking antibodies can generate potent anti-tumor responses by encouraging the immune system to seek and destroy cancer cells. At this time, the United States Food and Drug Administration has approved three checkpoint-blocking antibodies in three disease indications, and additional approvals are expected to broaden the clinical scope of immunotherapy. Herein, we review the clinical development of CTLA-4-, PD-1-, and PD-L1-blocking antibodies across tumor types and briefly discuss areas of active investigation of potential biomarkers.

Immunomodulatory Drugs: Immune Checkpoint Agents in Acute Leukemia

Intrinsic immune responses to acute leukemia are inhibited by a variety of mechanisms, such as aberrant antigen expression by leukemia cells, secretion of immunosuppressive cytokines and expression of inhibitory enzymes in the tumor microenvironment, expansion of immunoregulatory cells, and activation of immune checkpoint pathways, all leading to T cell dysfunction and/or exhaustion. Leukemic cells, similar to other tumor cells, hijack these inhibitory pathways to evade immune recognition and destruction by cytotoxic T lymphocytes. Thus, blockade of immune checkpoints has emerged as a highly promising approach to augment innate anti-tumor immunity in order to treat malignancies. Most evidence for the clinical efficacy of this immunotherapeutic strategy has been seen in patients with metastatic melanoma, where anti-CTLA-4 and anti-PD-1 antibodies have recently revolutionized treatment of this lethal disease with otherwise limited treatment options. To meet the high demand for new treatment strategies in acute leukemia, clinical testing of these promising therapies is commencing. Herein, we review the biology of multiple inhibitory checkpoints (including CTLA-4, PD-1, TIM-3, LAG-3, BTLA, and CD200R) and their contribution to immune evasion by acute leukemias. In addition, we discuss the current state of preclinical and clinical studies of immune checkpoint inhibition in acute leukemia, which seek to harness the body's own immune system to fight leukemic cells.

Single versus combined immunoregulatory approach using PD-1 and CTLA-4 modulators in controlling sepsis

INTRODUCTION

Sepsis is a disease process characterized by an extreme inflammatory response followed by a period of severe immunosuppression. In recent years, there has been improved survival in the initial immune response during systemic inflammatory response syndrome, and compensatory anti-inflammatory response, yet is mostly unchanged with 18-30% mortality during the later stage of sepsis despite numerous Phase 3 clinical trials. Areas covered: This review article presents a critical evaluation of the most promising newer studies aimed at improving the immunosuppressive stage of sepsis. Administration of DHEA/AED/AET show promise in improving survival. Blockade of signaling pathways for PD-1/PD-L1/CTLA-4, and partial blockade of TREM-1 signaling, and modification to sTREM-1 and the JAK/STAT pathway are promising methods of restoring host immune response and improving survival. While there has been significant progress, currently no findings have been translated into effective clinical interventions. Expert commentary: Clinical success by immunomodulation with individual immune mediator is encouraging and should progress to evaluating combined methods of immunoregulation. Since most of the animal studies do not reproduce human sepsis, development of better animal models and moving toward human studies for intervention will lead to the most beneficial findings in translational science.

Immuno-oncology Clinical Trial Design: Limitations, Challenges, and Opportunities

Recent advances in immuno-oncology and regulatory approvals have been rapid and paradigm shifting in many difficult-to-treat malignancies. Despite immune checkpoint inhibitor therapy becoming the standard of care across multiple tumor types, there are many unanswered questions that need to be addressed before this therapeutic modality can be fully harnessed. Areas of limitations include treatment of patients not sufficiently represented in clinical trials, uncertainty of the optimal treatment dosing and duration, and lack of understanding regarding long-term immune related toxicities and atypical tumor responses. Patients such as those with autoimmune disease, chronic viral infections, limited performance status, and brain metastases were often excluded from initial trials due to concerns of safety. However, limited data suggest that some of these patients can benefit from therapy with manageable toxicities; thus, future studies should incorporate these patients to clearly define safety and efficacy. There are still controversies regarding the optimal dosing strategy that can vary from weight-based to flat dosing, with undefined treatment duration. Further elucidation of the optimal dosing approach and evaluation of predictive biomarkers should be incorporated in the design of future trials. Finally, there are long-term immune-mediated toxicities, atypical tumor responses such as pseudoprogression and endpoints unique to immuno-oncology that are not adequately captured by traditional trial designs; thus, novel study designs are needed. In this article, we discuss in detail the above challenges and propose needed areas of research for exploration and incorporation in the next generation of immuno-oncology clinical trials.

Repeated measures dose-finding design with time-trend detection in the presence of correlated toxicity data

BACKGROUND

Phase I trials are designed to determine the safety, tolerability, and recommended phase 2 dose of therapeutic agents for subsequent testing. The dose-finding paradigm has thus traditionally focused on identifying the maximum tolerable dose of an agent or combination therapy under the assumption that there is a non-decreasing relationship between dose-toxicity and dose-efficacy. The dose is typically determined based on the probability of severe toxicity observed during the first treatment cycle. A novel endpoint, the total toxicity profile, was previously developed to account for the multiple toxicity types and grades experienced in the first cycle. More recently, this was extended to a repeated measures design based on the total toxicity profile to account for longitudinal toxicities over multiple treatment cycles in the absence of within-patient correlation.

METHODS

In this work, we propose to extend the design in the presence of within-patient correlation. Furthermore, we provide a framework to detect a toxicity time trend (toxicity increasing, decreasing, or stable) over multiple treatment cycles. We utilize a linear mixed model in the Bayesian framework, with the addition of Bayesian risk functions for decision-making in dose assignment.

RESULTS

The performance of this design was evaluated using simulation studies and real data from a phase I trial. We demonstrated that using available toxicity data from all cycles of treatment improves the accuracy of maximum tolerated dose identification and allows for the detection of a time trend. The performance is consistent regardless of the strength of the within-patient correlation. In addition, the use of a quasi-continuous total toxicity profile score significantly increased the power to detect time trends compared to when binary data only were used.

CONCLUSION

The increased interest in molecularly targeted agents and immunotherapies in oncology necessitates innovative phase I study designs. Our proposed framework provides a tool to tackle some of the challenges presented by these novel agents, specifically through the ability to understand patterns of toxicity over time, which is important in the cases of cumulative or late toxicities.

Tremelimumab as second-line or third-line treatment in relapsed malignant mesothelioma (DETERMINE): a multicentre, international, randomised, double-blind, placebo-controlled phase 2b trial

BACKGROUND

New therapeutic strategies for malignant mesothelioma are urgently needed. In the DETERMINE study, we investigated the effects of the cytotoxic-T-lymphocyte-associated antigen 4 (CTLA-4) monoclonal antibody tremelimumab in patients with previously treated advanced malignant mesothelioma.

METHODS

DETERMINE was a double-blind, placebo-controlled, phase 2b trial done at 105 study centres across 19 countries in patients with unresectable pleural or peritoneal malignant mesothelioma who had progressed after one or two previous systemic treatments for advanced disease. Eligible patients were aged 18 years or older with Eastern Cooperative Oncology Group performance status of 0 or 1 and measurable disease as defined in the modified Response Evaluation Criteria In Solid Tumors (RECIST) version 1.0 for pleural mesothelioma or RECIST version 1.1 for peritoneal mesothelioma. Patients were randomly assigned (2:1) in blocks of three, stratified by European Organisation for Research and Treatment of Cancer status (low risk vs high risk), line of therapy (second line vs third line), and anatomic site (pleural vs peritoneal), by use of an interactive voice or web system, to receive intravenous tremelimumab (10 mg/kg) or placebo every 4 weeks for 7 doses and every 12 weeks thereafter until a treatment discontinuation criterion was met. The primary endpoint was overall survival in the intention-to-treat population. Safety was assessed in all patients who received at least one dose of study drug. The trial is ongoing but no longer recruiting participants, and is registered with ClinicalTrials.gov, number NCT01843374.

FINDINGS

Between May 17, 2013, and Dec 4, 2014, 571 patients were randomly assigned to receive tremelimumab (n=382) or placebo (n=189), of whom 569 patients received treatment (two patients in the tremelimumab group were excluded from the safety population because they did not receive treatment). At the data cutoff date (Jan 24, 2016), 307 (80%) of 382 patients had died in the tremelimumab group and 154 (81%) of 189 patients had died in the placebo group. Median overall survival in the intention-to-treat population did not differ between the treatment groups: 7·7 months (95% CI 6·8-8·9) in the tremelimumab group and 7·3 months (5·9-8·7) in the placebo group (hazard ratio 0·92 [95% CI 0·76-1·12], p=0·41). Treatment-emergent adverse events of grade 3 or worse occurred in 246 (65%) of 380 patients in the tremelimumab group and 91 (48%) of 189 patients in the placebo group; the most common were dyspnoea (34 [9%] patients in the tremelimumab group vs 27 [14%] patients in the placebo group), diarrhoea (58 [15%] vs one [<1%]), and colitis (26 [7%] vs none). The most common serious adverse events were diarrhoea (69 [18%] patients in the tremelimumab group vs one [<1%] patient in the placebo group), dyspnoea (29 [8%] vs 24 [13%]), and colitis (24 [6%] vs none). Treatment-emergent events leading to death occurred in 36 (9%) of 380 patients in the tremelimumab group and 12 (6%) of 189 in the placebo group; those leading to the death of more than one patient were mesothelioma (three [1%] patients in the tremelimumab group vs two [1%] in the placebo group), dyspnoea (three [1%] vs two [1%]); respiratory failure (one [<1%] vs three [2%]), myocardial infarction (three [1%] vs none), lung infection (three [1%] patients vs none), cardiac failure (one [<1%] vs one [<1%]), and colitis (two [<1%] vs none). Treatment-related adverse events leading to death occurred in five (1%) patients in the tremelimumab group and none in the placebo group. The causes of death were lung infection in one patient, intestinal perforation and small intestinal obstruction in one patient; colitis in two patients, and neuritis and skin ulcer in one patient.

INTERPRETATION

Tremelimumab did not significantly prolong overall survival compared with placebo in patients with previously treated malignant mesothelioma. The safety profile of tremelimumab was consistent with the known safety profile of CTLA-4 inhibitors. Investigations into whether immunotherapy combination regimens can provide greater efficacy than monotherapies in malignant mesothelioma are ongoing.

FUNDING

AstraZeneca.

Molecular Markers for Colorectal Cancer

Colorectal cancers develop through at least 3 major pathways, including chromosomal instability, mismatch repair, and methylator phenotype. These pathways can coexist in a single individual and occur in both sporadic and inherited colorectal cancers. In spite of the unique molecular and genetic signatures of colorectal cancers, nonspecific chemotherapy based on the antineoplastic effects of 5-fluorouracil is the cornerstone of therapy for stage III and some stage II disease. Techniques to recognize colorectal cancer at the molecular level have facilitated development of new signature drugs designed to inhibit the unique pathways of colorectal cancer growth and immunity.

Potential targeting of B7-H4 for the treatment of cancer

Observations noting the presence of white blood cell infiltrates within tumors date back more than a century, however the cellular and molecular mechanisms regulating tumor immunity continue to be elucidated. The recent successful use of monoclonal antibodies to block immune regulatory pathways to enhance tumor-specific immune responses for the treatment of cancer has encouraged the identification of additional immune regulatory receptor/ligand pathways. Over the past several years, a growing body of data has identified B7-H4 (VTCN1/B7x/B7S1) as a potential therapeutic target for the treatment of cancer. The potential clinical significance of B7-H4 is supported by the high levels of B7-H4 expression found in numerous tumor tissues and correlation of the level of expression on tumor cells with adverse clinical and pathologic features, including tumor aggressiveness. The biological activity of B7-H4 has been associated with decreased inflammatory CD4⁺ T-cell responses and a correlation between B7-H4-expressing tumor-associated macrophages and FoxP3⁺ regulatory T cells (Tregs) within the tumor microenvironment. Since B7-H4 is expressed on tumor cells and tumor-associated macrophages in various cancer types, therapeutic blockade of B7-H4 could favorably alter the tumor microenvironment allowing for antigen-specific clearance tumor cells. The present review highlights the therapeutic potential of targeting B7-H4.

Checkpoint inhibition for colorectal cancer: progress and possibilities

Colorectal cancer (CRC) remains the third most common cause of cancer death in the USA. Despite an increase in the repertoire of treatment options available for CRC, median overall survival has plateaued at approximately 2.5 years. Strategies that engage the patient's native immune system to overcome checkpoint inhibition have proven to be promising in subsets of CRCs, specifically those with mismatch repair deficiency. Further studies are required to determine combinations of standard therapies with immunotherapy drugs and to discover the best biomarkers to predict response. This review provides insight into the progress made in treating patients with advanced CRC with immunotherapeutics and the areas that demand further research to make these drugs more effective in this patient population.

Tremelimumab-Induced Graves Hyperthyroidism

Tremelimumab and ipilimumab are monoclonal antibodies directed against the extracellular domain of cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and have been used as immunotherapies against immune checkpoints that suppress T-cell activation. Anti-CTLA-4 antibody-based therapies have been shown to be effective in treating various cancers including metastatic melanoma. However, a few immune-related adverse events including hypophysitis and thyroid disorder have been reported, mostly developed within the first year of receiving treatment. We report a case of tremelimumab-induced Graves hyperthyroidism in a 55-year-old man who was diagnosed with metastatic melanoma after 8 years of tremelimumab therapy. He had no personal or family history of thyroid or autoimmune diseases. His biochemical profile was in keeping with Graves disease, with raised serum free thyroid hormones, suppressed thyroid-stimulating hormone concentration, and raised thyrotropin receptor antibody level. He was treated with carbimazole as part of the block and replace therapy, without complications. Tremelimumab therapy was temporarily discontinued and recommenced when he was rendered biochemically euthyroid. There has been no further relapse of Graves hyperthyroidism since the discontinuation of block and replace therapy. The mechanistic profile of anti-CTLA-4-induced thyroid dysfunction and the long-term endocrine safety of this therapeutic approach remain unclear. It is important to monitor thyroid functions in patients receiving anti-CTLA-4 therapies, as their effects on endocrine systems could be more latent or prolonged than the data from current clinical trials suggest. Antithyroid drug therapy was safe and effective alongside anti-CTLA-4 therapy without compromising antitumour treatment efficacy.

B7-H4 as an independent prognostic indicator of cancer patients: a meta-analysis

The expression of B7-H4 was observed in a variety of tumors, however the prognostic value in cancer was still controversial. Therefore, we conducted this meta-analysis to explore the potential role of B7-H4 in cancer prognostic prediction. Twenty-seven studies including 3771 patients were brought into the analysis according to the inclusion and exclusion criteria. The pooled results demonstrated that elevated B7-H4 predicted a poor OS (HR = 1.93, 95% CI 1.71-2.18, P < 0.001) and DFS (HR = 1.84, 95% CI 1.46-2.33, P < 0.001). Subgroup analysis showed that races, tumor types, sample sources, analysis types, sources of HR and sample sizes exhibited non-significant distinctions with OS (P_S = 0.878, P_S = 0.143, P_S = 0.613, P_S = 0.639, P_S = 0.48 and P_S = 0.528, respectively). PubMed, Embase and the Cochrane Library were searched up to April 7, 2017, to recognize the available studies for assessing the association between B7-H4 and cancer patients’ outcome. We extracted the hazard ratio (HR), relative ratio (RR), odds ratio (OR) with their 95% confidence interval (CI) for overall survival (OS) or disease-free survival (DFS) as the effect size (ES) for the analysis. This meta-analysis demonstrates high expression of B7-H4 is a negative correlation with the outcome of cancer patients.

Cancer immunotherapy - immune checkpoint blockade and associated endocrinopathies

Advances in cancer therapy in the past few years include the development of medications that modulate immune checkpoint proteins. Cytotoxic T-lymphocyte antigen 4 (CTLA4) and programmed cell death protein 1 (PD1) are two co-inhibitory receptors that are expressed on activated T cells against which therapeutic blocking antibodies have reached routine clinical use. Immune checkpoint blockade can induce inflammatory adverse effects, termed immune-related adverse events (IRAEs), which resemble autoimmune disease. In this Review, we describe the current data regarding immune-related endocrinopathies, including hypophysitis, thyroid dysfunction and diabetes mellitus. We discuss the clinical management of these endocrinopathies within the context of our current understanding of the mechanisms of IRAEs.

Immunotherapy in malignant melanoma: recent approaches and new perspectives

Immunotherapy has radically transformed the management of metastatic malignant melanoma. Ipilimumab, a CTLA-4-targeted monoclonal antibody, was the first immunotherapeutic drug to reach a survival benefit compared with traditional chemotherapy. PD-1 targeted therapies, pembrolizumab and nivolumab, have demonstrated, in recent clinical trials, to be even more effective and safer. PD-1 and CTLA-4 blockade combination appears to improve the outcomes achieved so far, although increasing toxicity. However, many questions concerning the optimal timing of administration or the most adequate sequence of treatment are yet to be answered.

Controlled release of antigen and Toll-like receptor ligands from PLGA nanoparticles enhances immunogenicity

AIM

Dendritic cells rapidly capture nanoparticles and induce a potent cellular immune response. It is yet unknown whether the immunological response induced by slow release of encapsulated versus soluble antigen and adjuvant is superior.

MATERIALS & METHODS

The kinetics of poly(lactic-co-glycolic acid) PLGA nanoparticles antigen release was studied by the DQ-bovine serum albumin (BSA) self-quenching antigen model. The immunological response induced was evaluated by means of dendritic cell activation/maturation markers, cytokine production and their ability to drive antigen-specific T-cell proliferation.

RESULTS & CONCLUSION

PLGA-encapsulated antigen and adjuvant showed an enhanced T-cell response when compared with soluble vaccine components by increasing antigenicity and adjuvanticity. Although the kinetic profile followed the same pattern, encapsulation increased strength and duration of the response.

Immune-Related Adverse Events Associated with Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICIs), including antibodies targeting cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death protein-1 (PD-1), have shown durable treatment responses in multiple tumor types by enhancing antitumor immunity. However, removal of self-tolerance can induce autoimmunity and produce a unique immune-driven toxicity profile, termed immune-related adverse events (irAEs). As ICIs gain approval for a growing number of indications, it is imperative clinicians increase their knowledge of and ability to manage irAEs. This review examines the etiology, presentation, kinetics, and treatment of irAEs and aims to provide practical guidance for clinicians.

Novel avenues in immunotherapies for colorectal cancer

Since it is known that the immune system affects tumor growth, it has been studied if immunotherapy can be developed to combat cancer. While some successes have been claimed, the increasing knowledge on tumor-immune interactions has, however, also shown the limitations of this approach. Tumors may show selective outgrowth of cells escaped from immune control. Escape variants arise spontaneously due to the genetically instable nature of tumor cells. This is one of the most obvious limitations of cancer immunotherapy. However, new therapies are becoming available, designed to respond to tumor-immune escape.

Determination of the starting dose in the first-in-human clinical trials with monoclonal antibodies: a systematic review of papers published between 1990 and 2013

A systematic review was performed to evaluate how the maximum recommended starting dose (MRSD) was determined in first-in-human (FIH) studies with monoclonal antibodies (mAbs). Factors associated with the choice of each MRSD determination method were also identified. PubMed was searched for FIH studies with mAbs published in English between January 1, 1990 and December 31, 2013, and the following information was extracted: MRSD determination method, publication year, therapeutic area, antibody type, safety factor, safety assessment results after the first dose, and number of dose escalation steps. Seventy-nine FIH studies with mAbs were identified, 49 of which clearly reported the MRSD determination method. The no observed adverse effects level (NOAEL)-based approach was the most frequently used method, whereas the model-based approach was the least commonly used method (34.7% vs 16.3%). The minimal anticipated biological effect level (MABEL)- or minimum effective dose (MED)-based approach was used more frequently in 2011–2013 than in 1990–2007 (31.6% vs 6.3%, P=0.036), reflecting a slow, but steady acceptance of the European Medicines Agency’s guidance on mitigating risks for FIH clinical trials (2007). The median safety factor was much lower for the MABEL- or MED-based approach than for the other MRSD determination methods (10 vs 32.2–53). The number of dose escalation steps was not significantly different among the different MRSD determination methods. The MABEL-based approach appears to be safer and as efficient as the other MRSD determination methods for achieving the objectives of FIH studies with mAbs faster.

The evaluation of immunotherapy and chemotherapy treatment on melanoma: a network meta-analysis

BACKGROUND

Melanoma is a highly malignant tumor that develops from a neural crest derivative called melanocytes. Chemotherapy is recommended for patients with stage III/IV melanoma. Immunomodulation has also been shown to effectively improve the survival rate of such patients. In the current study, we aimed to perform a network meta-analysis on the therapeutic value of chemotherapy and immunotherapy on melanoma.

RESULTS

Twenty randomized controlled trials (RCTs) were enrolled in the study. Our Results indicated that ipilimumab + nivolumab had the highest response rate among all therapies, pembrolizumab also had a good efficacy with an excellent tolerance. Chemotherapy had a low response rate, high adverse effects and progressive diseases qualities, therefore it is not recommended as a preferred treatment for patients with advanced melanoma.

METHODS

The Cochrane library, PubMed and Embase databases were searched for relevant articles. Results of the pair-wise meta-analysis were illustrated by odd ratios (ORs) and corresponding 95% confidence intervals (CIs). Network meta-analysis was performed using a random-effects model under Bayesian framework. Results were illustrated by cumulative ORs and corresponding 95% credible interval (CrIs). The probabilities and outcomes of each treatment were ranked and summarized using the surface under the cumulative ranking curve (SUCRA).

CONCLUSIONS

We recommend pembrolizumab as the preferred treatment due to its high efficacy and low adverse effects, combination of ipilimumab and nivolumab could be used in severe symptoms.

Pharmacological interventions for melanoma: Comparative analysis using bayesian meta-analysis

We conducted a network meta-analysis in order to compare different strategies for managing melanoma patients. Electronic databases were searched for eligible randomized trials that compared different strategies in efficacy and tolerability. Five interventions were associated with a significant improvement in PFS over chemotherapy (all HR < 1): Ipilimumab, Tremelimumab, Nivolumab, Pembrolizumab 2 mg/kg and Ipilimumab + Nivolumab. Three interventions exhibited significantly improved OS results over chemotherapy (all HR < 1): Ipilimumab, Nivolumab and Ipilimumab + Chemotherapy. Four interventions were superior to chemotherapy in CR and PR (all OR > 1): Nivolumab, Pembrolizumab 10 mg/kg, Pembrolizumab 2 mg/kg and Ipilimumab + Nivolumab. However, the other seven interventions were associated with an increased risk of pruritus compared to chemotherapy (all OR > 1). Ipilimumab, Tremelimumab, Ipilimumab + Nivolumab and Ipilimumab + Chemotherapy might result in a higher risk of diarrhea compared to chemotherapy (all OR > 1). Immune checkpoint therapy or combined interventions might be more effective than chemotherapy for managing melanoma patients. However, chemotherapy appears to be more tolerable than these combined strategies with respect to adverse events.

Responses to immune checkpoint inhibitors in nonagenarians

The incidence of melanoma continues to rise with the most rapid increase seen in the elderly population. Historically, elderly patients with advanced melanoma have had dismal clinical outcomes, in part, due to distinct tumor biology, and often ineligibility for effective therapies during their development. In addition, due to relatively few geriatric patients being accrued to clinical trials of novel immunotherapeutics, there is a paucity of data regarding their safety and efficacy. Herein, we present the clinical course of three consecutive nonagenarians (≥90 y old) with metastatic melanoma, who were treated with single-agent or combination immune checkpoint inhibitors. Two patients experienced complete or partial responses with acceptable safety profiles, and one other tolerated therapy well although a significant response was not noted. These cases suggest that with close monitoring, even very elderly patients with advanced cancers and acceptable performance status may tolerate and benefit from immune checkpoint inhibitors.

A phase I study of intratumoral ipilimumab and interleukin-2 in patients with advanced melanoma

PURPOSE

Intratumoral interleukin-2 (IL-2) is effective but does not generate systemic immunity. Intravenous ipilimumab produces durable clinical response in a minority of patients, with potentially severe toxicities. Circulating anti-tumor T cells activated by ipilimumab may differ greatly from tumor-infiltrating lymphocytes activated by intratumoral ipilimumab in phenotypes and functionality. The objective of this study was to primarily assess the safety of intratumoral ipilimumab/IL-2 combination and to obtain data on clinical efficacy.

RESULTS

There was no dose limiting toxicity. While local response of injected lesions was observed in 67% patients (95% CI, 40%-93%), an abscopal response was seen in 89% (95% CI, 68%-100%). The overall response rate and clinical benefit rate by immune-related response criteria (irRC) was 40% (95% CI, 10%-70%) and 50% (95% CI, 19%-81%), respectively. Enhanced systemic immune response was observed in most patients and correlated with clinical responses.

EXPERIMENTAL DESIGN

Twelve patients with unresectable stages III/IV melanoma were enrolled. A standard 3+3 design was employed to assess highest tolerable intratumoral dose of ipilimumab and IL-2 based on toxicity during the first three weeks. Escalated doses of ipilimumab was injected into only one lesion weekly for eight weeks in cohorts of three patients. A fixed dose of IL-2 was injected three times a week into the same lesion for two weeks, followed by two times a week for six weeks.

CONCLUSIONS

Intratumoral injection with the combination of ipilimumab/IL-2 is well tolerated and generates responses in both injected and non-injected lesions in the majority of patients.

Immune checkpoint inhibitor-related hypophysitis and endocrine dysfunction: clinical review

Immune checkpoint inhibitors are a new and effective class of cancer therapy, with ipilimumab being the most established drug in this category. The drugs' mechanism of action includes promoting the effector T cell response to tumours and therefore increased autoimmunity is a predictable side effect. The endocrine effects of these drugs include hypophysitis and thyroid dysfunction, with rare reports of adrenalitis. The overall incidence of hypophysitis with these medications is up to 9%. Primary thyroid dysfunction occurs in up to 15% of patients, with adrenalitis reported in approximately 1%. The mean onset of endocrine side effects is 9 weeks after initiation (range 5-36 weeks). Investigation and/or screening for hypophysitis requires biochemical and radiological assessment. Hypopituitarism is treated with replacement doses of deficient hormones. Since the endocrine effects of immune checkpoint inhibitors are classed as toxic adverse events, most authors recommend both discontinuation of the immune checkpoint inhibiting medication and 'high-dose' glucocorticoid treatment. However, this has been challenged by some authors, particularly if the endocrine effects can be managed (e.g. pituitary hormone deficiency), and the therapy is proving effective as an anticancer agent. This review describes the mechanism of action of immune checkpoint inhibitors and details the key clinical endocrine-related consequences of this novel class of immunotherapies.

The European Organization for Research and Treatment of Cancer perspective on designing clinical trials with immune therapeutics

Cancer immunotherapy has had a major impact on the established paradigms of drug development and clinical trial research. The innovative mechanism of action of these compounds has resulted in new patterns of response and safety profiles, which pose challenges for the classical trial methodology. In this review we report on the search for the maximum tolerated dose, the recommended phase II dose and the appropriate target population in phase I trials. We provide some statistical considerations on the choice of endpoints for phase II and III trials and the limitations of frequently used trial designs in the presence of a delayed treatment effect, which may be induced by the immune modulating effect of the checkpoint inhibitors. We summarize the currently available data on the safety profile of these new compounds, which can guide protocol safety recommendations. Finally, we report on the current evidence of biomarker development.

Melanoma immunotherapy dominates the field

The incidence of melanoma is increasing worldwide and despite early detection and intervention, the number of patients dying from metastatic disease continues to rise. The prognosis of advanced melanoma remains poor, with median survival between 6 and 9 months. Over the past 30 years and despite extensive clinical research, the treatment options for metastatic disease were limited and melanoma is still considered as one of the most therapy-resistant malignancies. Single-agent and combination chemotherapy, hormonal therapy, biochemotherapy, immunotherapy, targeted agent therapy and combination regimens failed to show a significant improvement in overall survival (OS). Recent advances and in-depth understanding of the biology of melanoma, have contributed to the development of new agents. Based on the molecular and immunological background of the disease, these new drugs have shown benefit in overall and progression-free survival (PFS). As the picture of the disease begins to change, oncologists need to alter their approach to melanoma treatment and consider disease biology together with targeted individualized treatment. In this review the authors attempt to offer an insight in the present and past melanoma treatment options, with a focus on the recently approved immunotherapeutic agents and the clinical perspectives of these new weapons against metastatic melanoma.

Folate-conjugated immunoglobulin targets melanoma tumor cells for NK cell effector functions

The folate receptor (FR) is overexpressed on the vascular side of cancerous cells including those of the breast, ovaries, testes, and cervix. We hypothesized that a folate-conjugated immunoglobulin (F-IgG) would bind to the FR that is overexpressed on melanoma tumor cells to target these cells for lysis by natural killer (NK) cells. Folate receptor expression was confirmed in the Mel-39 (human melanoma) cell line by flow cytometry and immunoblot analysis using KB (human oral epithelial) and F01 (human melanoma) as a positive and a negative control, respectively. FR-positive and FR-negative cell lines were treated with F-IgG or control immunoglobulin G in the presence or absence of cytokines to determine NK cell ability to lyse FR-positive cell lines. NK cell activation was significantly upregulated and lysis of Mel 39 tumor cells increased following treatment with F-IgG compared with control immunoglobulin G at all effector : target (E : T) ratios (P<0.01). This trend further increased by NK cell stimulation with the activating cytokine interleukin-12. NK cell production of cytokines such as interferon-gamma, macrophage inflammatory protein 1α, and regulated on activation normal T-cell expressed and secreted (RANTES) was also significantly increased in response to costimulation with interleukin-12 stimulation and F-IgG-coated Mel 39 target cells compared with controls (P<0.01). In contrast, F-IgG did not bind to the FR-negative cell line F01 and had no significant effect on NK cell lysis or cytokine production. This research indicates the potential use of F-IgG for its ability to induce an immune response from NK cells against FR-positive melanoma tumor cells, which can be further increased by the addition of cytokines.

Immune Checkpoint Inhibitors: Review and Management of Endocrine Adverse Events

: In recent years, immune checkpoint inhibitors have emerged as effective therapies for advanced neoplasias. As new checkpoint target blockers become available and additional tumor locations tested, their use is expected to increase within a short time. Immune-related adverse events (irAEs) affecting the endocrine system are among the most frequent and complex toxicities. Some may be life-threatening if not recognized; hence, appropriate guidance for oncologists is needed. Despite their high incidence, endocrine irAEs have not been fully described for all immunotherapy agents available. This article is a narrative review of endocrinopathies associated with cytotoxic T lymphocyte-associated antigen-4, blockade of programmed death receptor 1 and its ligand inhibitors, and their combination. Thyroid dysfunction is the most frequent irAE reported, and hypophysitis is characteristic of ipilimumab. Incidence, timing patterns, and clinical presentation are discussed, and practical recommendations for clinical management are suggested. Heterogeneous terminology and lack of appropriate resolution criteria in clinical trials make adequate evaluation of endocrine AEs difficult. It is necessary to standardize definitions to contrast incidences and characterize toxicity patterns. To provide optimal care, a multidisciplinary team that includes endocrinology specialists is recommended.

IMPLICATIONS FOR PRACTICE

Immune checkpoint inhibitors are already part of oncologists' therapeutic arsenal as effective therapies for otherwise untreatable neoplasias, such as metastatic melanoma or lung cancer. Their use is expected to increase exponentially in the near future as additional agents become available and their approval is extended to different tumor types. Adverse events affecting the endocrine system are among the most frequent and complex toxicities oncologists may face, and some may be life-threatening if not recognized. This study reviews endocrinopathies associated to immune checkpoint inhibitors available to date. Incidence, timing patterns, and clinical presentation are discussed, and practical recommendations for management are proposed.

A phase 2 study of tremelimumab in patients with advanced uveal melanoma

Similar to cutaneous melanoma, several strategies of immune escape have been documented in uveal melanomas (UMs). We hypothesized that these cancers could respond to cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) inhibition with tremelimumab by potentiating T-cell activation. This was an open-label, multicentre phase 2 study in patients with advanced UM who had not received prior immunotherapy. Patient received tremelimumab at 15 mg/kg administered every 90 days for up to four cycles. The primary endpoint was 6-month progression-free survival (PFS). Secondary endpoints were safety, durable response rate, objective response rate, duration of objective response, duration of complete response, and median overall survival (OS). Eleven patients, all with M1c disease, were enrolled with no responses observed. The median follow-up was 11 months (range 2-36 months). The median PFS was 2.9 months (95% confidence interval 2.8-3.0) and the 6-month PFS rate was 9.1%. The median OS was 12.8 months (95% confidence interval 3.8-19.7). Toxicities were consistent with CTLA-4 blockade and were manageable. Although the median OS of 12.8 months and the manageable toxicity profile of tremelimumab observed in this study seem promising, the modest 6-month PFS and the lack of responses observed resulted in the study being stopped due to futility at the first interim stage. To date, no systemic treatment has demonstrated a survival benefit in patients with advanced UM. The standard treatment for patients with advanced UM should be a clinical trial.

Immunotherapy for lung cancer

Treatment of lung cancer remains a challenge, and lung cancer is still the leading cause of cancer-related mortality. Immunotherapy has previously failed in lung cancer but has recently emerged as a very effective new therapy, and there is now growing worldwide enthusiasm in cancer immunotherapy. We summarize why immune checkpoint blockade therapies have generated efficacious and durable responses in clinical trials and why this has reignited interest in this field. Cancer vaccines have also been explored in the past with marginal success. Identification of optimal candidate neoantigens may improve cancer vaccine efficacy and may pave the way to personalized immunotherapy, alone or in combination with other immunotherapy such as immune checkpoint blockade. Understanding the steps in immune recognition and eradication of cancer cells is vital to understanding why previous immunotherapies failed and how current therapies can be used optimally. We hold an optimistic view for the future prospect in lung cancer immunotherapy.

Dendritic Cell-Based Immunotherapy: State of the Art and Beyond

Dendritic cell (DC) vaccination in cancer patients aims to induce or augment an effective antitumor immune response against tumor antigens and was first explored in a clinical trial in the 1990s. More than two decades later, numerous clinical trials have been performed or are ongoing with a wide variety of DC subsets, culture protocols, and treatment regimens. The safety of DC vaccination and its ability to induce antitumor responses have clearly been established; however, although scattered patients with long-term benefit were reported, DC vaccines have not yet fulfilled their promise, perhaps mainly due to the lack of large-scale well-conducted phase II/III trials. To allow meaningful multicenter phase III trials, the production of DC vaccines should be standardized between centers which is now becoming feasible. To improve the efficacy of DC-based immunotherapy, it could be combined with other treatments.

Tremelimumab: research and clinical development

The immune checkpoint therapy is a relatively recent strategy that aims to tweak the immune system to effectively attack cancer cells. The understanding of the immune responses and their regulation at the intracellular level and the development of fully humanized monoclonal antibodies are the pillars of an approach that could elicit durable clinical responses and even remission in some patients with cancer. Most of the immune checkpoints that regulate the T-cell responses (activation and inhibition) operate through proteins present on the cytoplasmic membrane of the immune cells. Therefore, specific antibodies capable of blocking the inhibitory signals should lead to unrestrained immune responses that supersede the inhibitory mechanisms, which are naturally present in the tumor microenviroment. The best-known and most successful targets for immune checkpoint therapy are the cytotoxic T-lymphocyte antigen-4 and programmed cell death-1 coreceptors. Tremelimumab (CP-675,206) is a fully humanized monoclonal antibody specific for cytotoxic T-lymphocyte antigen-4, which has been successfully used to treat patients with metastatic melanoma and some other cancers. Although still a work in progress, the use of tremelimumab as an immune checkpoint therapeutic agent is a promising approach alone or in combination with other anticancer drugs. Here, we review the use of this antibody in a number of clinical trials against solid tumors.

Coinhibitory Pathways in Immunotherapy for Cancer

The immune system is capable of recognizing tumors and eliminates many early malignant cells. However, tumors evolve to evade immune attack, and the tumor microenvironment is immunosuppressive. Immune responses are regulated by a number of immunological checkpoints that promote protective immunity and maintain tolerance. T cell coinhibitory pathways restrict the strength and duration of immune responses, thereby limiting immune-mediated tissue damage, controlling resolution of inflammation, and maintaining tolerance to prevent autoimmunity. Tumors exploit these coinhibitory pathways to evade immune eradication. Blockade of the PD-1 and CTLA-4 checkpoints is proving to be an effective and durable cancer immunotherapy in a subset of patients with a variety of tumor types, and additional combinations are further improving response rates. In this review we discuss the immunoregulatory functions of coinhibitory pathways and their translation to effective immunotherapies for cancer.

Immune based therapy for melanoma

A few years ago therapeutic options in advanced melanoma were very limited and the prognosis was somber. Although recent progresses are far from providing a cure for advanced melanoma, yet these have kindled new hopes and searching for a cure does not seem unreasonable. Seven new medicines have been authorized in various regions of the world in the recent past in the therapy of advanced melanoma, over half of them acting by mechanisms involving the immune system of the host. The anti-CTLA-4 (cytotoxic T lymphocyte associated protein-4) ipilimumab has been followed by anti-PD1 (programmed death1) inhibitors, more effective and safer. Very recently, the first oncolytic immunotherapy, talimogene laherparepvec (T-VEC) has been authorized for placing on the market and a variety of combinations of the new therapies are currently being evaluated or considered. Besides, a plethora of other molecules and approaches, especially monoclonal antibodies, are in the preliminary phases of clinical investigation and are likely to bring new benefits for the treatment of this potentially fatal form of cancer.

Augmentation of Immune Checkpoint Cancer Immunotherapy with IL18

PURPOSE

Recent clinical trials and animal models demonstrated that immune checkpoint blockade enhanced effector cell responses and tumor rejection; however, further development and improvement of cancer immunotherapy is necessary for more favorable objective responses. In this study, we examined the effect of IL18 on the antitumor effect of immune checkpoint inhibitors.

EXPERIMENTAL DESIGN

We examined the effect of IL18 on the peritoneal dissemination of CT-26 cells or tail vein injection metastasis of B16/F10 cells using antiprogrammed death-1 ligand-1 (αPD-L1) and/or anti-CTL-associated antigen-4 (αCTLA-4) mAbs.

RESULT

Massive ascites developed after intraperitoneal inoculation of CT-26, resulting in animal death within 30 days. Treatment of mice with αPD-L1 and/or αCTLA-4 significantly prolonged their survival, and a combination of the antibodies and IL18 provided a much greater therapeutic benefit. The combination modality led to the accumulation of precursor of mature natural killer (pre-mNK) cells in the peritoneal cavity together with increased CD8(+) T and decreased CD4(+)CD25(+)Foxp3(+) T cells. Depletion of the pre-mNK cells abrogated the therapeutic effects and increased the number of CD4(+)CD25(+)Foxp3(+) T cells. The combination treatment also suppressed tail vein injection metastasis of B16/F10 cells.

CONCLUSIONS

The results demonstrated that IL18 enhanced therapeutic effects of immune checkpoint blockade against peritoneal dissemination of carcinoma or tail vein injection metastasis of melanoma through accumulation of pre-mNK cells, memory-type CD8(+) T cells, and suppression of CD4(+)CD25(+)Foxp3(+) T cells. A combination of immune checkpoint inhibitors with IL18 may give a suggestion to the development of next-generation cancer immunotherapy. Clin Cancer Res; 22(12); 2969-80. ©2016 AACR.

Immune-related adverse events with immune checkpoint blockade: a comprehensive review

Cancer immunotherapy is coming of age; it has prompted a paradigm shift in oncology, in which therapeutic agents are used to target immune cells rather than cancer cells. The first generation of new immunotherapies corresponds to antagonistic antibodies that block specific immune checkpoint molecules cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4), programmed cell death protein (PD-1) and its ligand PD-L1. Targeting these checkpoints in patients living with cancer had led to long-lasting tumour responses. By unbalancing the immune system, these new immunotherapies also generate dysimmune toxicities, called immune-related adverse events (IRAEs) that mainly involve the gut, skin, endocrine glands, liver, and lung but can potentially affect any tissue. In view of their undisputed clinical efficacy, anti-CTLA-4 and anti-PD-1 antibodies are entering in the routine oncological practice, and the number of patients exposed to these drugs will increase dramatically in the near future. Although steroids can be used to treat these IRAEs, the associated immunosuppression may compromise the antitumour response. Oncologists must be ready to detect and manage these new types of adverse events. This review focuses on the mechanisms of IRAE generation, putative relationship between dysimmune toxicity and antitumour efficacy, as a basis for management guidelines.

Challenges of phase 1 clinical trials evaluating immune checkpoint-targeted antibodies

BACKGROUND

Immunostimulatory monoclonal antibodies (imAbs) targeting immune checkpoint molecules are revolutionizing oncology not only regarding cancer therapeutics and clinical care, but also from a drug development point of view. A handful of first-generation molecules have been approved so far based on their tremendous efficacy, after an expedited development phase that has challenged most paradigms established in the era of conventional cytotoxic therapy and to some extent molecularly targeted agents. A huge wave of second-generation imAbs is just entering into phase 1 trials now, in monotherapy or in combination. In order to maximize their chances of success in early phase trials, and eventually for patients' benefit, their clinical development has to benefit from lessons learnt from previous imAbs phase 1 trials.

MATERIALS AND METHODS

We reviewed the early clinical development of anti-cytotoxic T-lymphocyte antigen 4 and anti-programmed death-1 receptor/ligand. Particularities of each agent, including safety, dose--toxicity and dose--efficacy relationships, scheduling, pharmacokinetics (PK), pharmacodynamics (PD), trial design, biomarkers, response assessment and overall drug development strategies, are described and challenged.

RESULTS

As opposed to conventional cytotoxic agents, dose of imAbs is not linearly associated with efficacy and toxicity. Therefore, the definition of a minimal immunologically active dose could be proposed. Traditional patient eligibility criteria might also be revisited as the toxicity profile and mechanism of toxicity--immune-related adverse events--are mostly known and their physiopathology somehow less unexpected than with molecularly targeted small molecules. Most challenging are the comprehensive investigation of complex PK and PD characteristics as well as the definition of patient selection biomarkers. Finally, the early focus on efficacy (and not only dose confirmation) in expansion cohorts challenges the traditional phase 1/2/3 drug development process.

CONCLUSION

Several drug development paradigms have been challenged by imAbs. Here, we discuss novel approaches for an efficient and successful drug development of these agents.

Long term survival with cytotoxic T lymphocyte-associated antigen 4 blockade using tremelimumab

PURPOSE

One of the hallmarks of cancer immunotherapy is the long duration of responses, evident with cytokines like interleukin-2 or a variety of cancer vaccines. However, there is limited information available on very long term outcomes of patients treated with anti-cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) antibodies. Tremelimumab is an anti-CTLA-4 antibody of immunoglobulin G2 (IgG2) isotype initially tested in patients with advanced melanoma over 12 years ago.

METHODS

We reviewed the outcomes of patients with advanced melanoma enrolled in four phase 1 and 2 tremelimumab trials at two sites to determine response rates and long-term survival.

RESULTS

A total of 143 patients were enrolled at two institutions from 2002 to 2008. Tremelimumab administration varied between a single dose of 0.01 mg/kg and 15 mg/kg every 3 months. Median overall survival was 13 months (95% confidence interval (CI), 10-16.6), ranging from less than a month to 12+ years. An objective response rate of 15.6% was observed, with median duration of response of 6.5 years, range of 3-136+ months. The Kaplan-Meier estimated 5 year survival rate was 20% (95% CI, 13-26%), with 10 and 12.5 year survival rates of 16% (95% CI, 9-23%).

CONCLUSIONS

CTLA-4 blockade with tremelimumab can lead to very long duration of objective anti-tumour responses beyond 12 years.

Predictive factors for immunotherapy in melanoma

Immunotherapy has emerged as an exciting strategy for cancer treatment. Therapeutic blockade of immune checkpoint regulators favors the ability of T cell responses to increase anti-tumor immunity. The cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed cell death-1 (PD-1) are two T cell-inhibitory receptors with independent mechanisms of action. Immune checkpoint inhibitors targeting either CTLA-4, PD-1 or its ligand PD-L1 are currently yielding promising results in terms of efficacy in several clinical studies with melanoma patients and are being developed and tested as immunotherapy agents for multiple cancer types. To date, no reliable predictors of activity and efficacy of immunotherapy have yet been identified or validated. Even so, determining which patients derive clinical benefit from immune checkpoint agents remains an important clinical question and efforts to identify predictive markers of response are ongoing. This article reviews the current potential predictive factors for CTLA-4 and PD-1/PD-L1 immune checkpoints inhibitors in melanoma.

Immune related adverse events associated with anti-CTLA-4 antibodies: systematic review and meta-analysis

BACKGROUND

Targeting CTLA-4 is a recent strategic approach in cancer control: blocking CTLA-4 enhances an antitumor immunity by promoting T-cell activation and cytotoxic T-lymphocyte proliferation. This induction of a tolerance break against the tumor may be responsible for immune-related adverse events (irAEs). Our objective was to assess the incidence and nature of irAEs in oncologic patients receiving anti-CTLA-4 antibodies (ipilimumab and tremelimumab).

METHODS

A systematic search of literature up to February 2014 was performed in MEDLINE, EMBASE, and Cochrane databases to identify relevant articles. Paired reviewers independently selected articles for inclusion and extracted data. Pooled incidence was calculated using R(©), package meta.

RESULTS

Overall, 81 articles were included in the study, with a total of 1265 patients from 22 clinical trials included in the meta-analysis. Described irAEs consisted of skin lesions (rash, pruritus, and vitiligo), colitis, and less frequently hepatitis, hypophysitis, thyroiditis, and some rare events such as sarcoidosis, uveitis, Guillain-Barré syndrome, immune-mediated cytopenia and polymyalgia rheumatic/Horton. The overall incidence of all-grade irAEs was 72 % (95 % CI, 65-79 %). The overall incidence of high-grade irAEs was 24 % (95 % CI, 18-30 %). The risk of developing irAEs was dependent of dosage, with incidence of all-grade irAEs being evaluated to 61 % (95 % CI, 56-66 %) for ipilimumab 3 mg/kg and 79 % (95 % CI, 69-89 %) for ipilimumab 10 mg/kg. Death due to irAEs occurred in 0.86 % of patients. The median time of onset of irAEs was about 10 weeks (IQR, 6-12) after the onset of treatment, corresponding with the first three cycles but varied according to the organ system involved. Such immune activation could also be indicative for tumor-specific T-cell activation and irAE occurrence was associated with clinical response to CTLA-4 blocking in 60 % of patients.

CONCLUSION

The price of potential long-term survival to metastatic tumors is an atypical immune toxicity, reflecting the mechanism of action of anti-CTLA-4 antibodies. A better knowledge of these irAEs and its management in a multidisciplinary approach will help to reduce morbidity and therapy interruptions.