Cytotoxic T-lymphocyte Antigen-4 Inhibitors Research Articles

ImmunoPET imaging of LAG-3 expression in tumor microenvironment with 68Ga-labelled cyclic peptides tracers: from bench to bedside

BackgroundLymphocyte activation gene 3 (LAG-3) has been considered as the next generation of immune checkpoint and a promising prognostic biomarker of immunotherapy. As with programmed cell death protein-1/programmed death-ligand 1...

Establishment of an animal model of immune-related adverse events induced by immune checkpoint inhibitors.

Immunotherapy, specifically immune checkpoint inhibitors (ICIs), has revolutionized cancer treatment. However, it can also cause immune-related adverse events (irAEs). This study aimed to develop a clinically practical animal model of irAEs using BALB/c mice. Subcutaneous tumors of mouse breast cancer 4T1 cells were generated in inbred BALB/c mice. The mice were treated with programmed death-1 (PD-1) and cytotoxic t-lymphocyte antigen 4 (CTLA-4) inhibitors once every 3 days for five consecutive administration cycles. Changes in tumor volume and body weight were recorded. Lung computed tomography (CT) scans were conducted. The liver, lungs, heart, and colon tissues of the mice were stained with hematoxylin-eosin (H&E) staining to observe inflammatory infiltration and were scored. Serum samples were collected, and enzyme-linked immunosorbent assay (ELISA) was used to detect the levels of ferritin, glutamic-pyruvic transaminase (ALT), tumor necrosis factor-α (TNF-α), interferon-gamma (IFN-γ), and interleukin-6 (IL-6). Mouse liver and lung cell suspensions were prepared, and changes in macrophages, T cells, myeloid-derived suppressor cells (MDSCs), and regulatory (Treg) cells were detected by flow cytometry. Mice treated with PD-1 and CTLA-4 inhibitors showed significant reductions in tumor volume and body weight. The tissue inflammatory scores in the experimental group were significantly higher than those in the control group. Lung CT scans of mice in the experimental group showed obvious inflammatory spots. Serum levels of ferritin, IL-6, TNF-α, IFN-γ, and ALT were significantly elevated in the experimental group. Flow cytometry analysis revealed a substantial increase in CD3+T cells, Treg cells, and macrophages in the liver and lung tissues of mice in the experimental group compared with the control group, and the change trend of MDSCs was opposite. The irAE-related animal model was successfully established in BALB/c mice using a combination of PD-1 and CTLA-4 inhibitors through multiple administrations with clinical translational value and practical. This model offers valuable insights into irAE mechanisms for further investigation.

ODP170 Check Point Inhibitor Associated Multi-Endocrine Dysfunction Presenting With Euglycemic Ketoacidosis

Abstract Introduction Immune check point inhibitors have become breakthrough therapy for many types of cancers. They inhibit one of two immune regulatory pathways, the cytotoxic T-lymphocyte antigen 4 (CTLA-4), and 'programmed death-1' (PD-1) and (PD-L1) pathways. Removing immune regulation allows for anti-cancer immune responses. They also cause immune related endocrine dysfunction such as hypophysitis, thyroiditis, diabetes mellitus (DM) and primary adrenal insufficiency (AI). We describe a patient on Pembrolizumab (PEM) (an anti-PD-1 inhibitor) who presented with new onset DM, euglycemic diabetic ketoacidosis (DKA) with simultaneous secondary AI. Case report 54-year-old woman with stage 4 non-small cell carcinoma of the lung (NSCLC) with known brain metastasis, was under therapy with carboplastin, paclitaxel and PEM, presented with headache, blurry vision and altered mental status. She had past history of Graves’ disease s/p radioactive iodine therapy, currently on levothyroxine. For two weeks, she had decreased oral intake, and generalized weakness. Upon presentation, she was cachectic, BP 152/65, pulse 117 and confabulating. Laboratory evaluation showed: serum glucose 72 mg/dL, Na 139 mmol/L, K 3.2 mmol/L, Cl 113 mmol/L, HCO3 11 mmol/L, anion gap 15 mmol/L, beta-hydroxybutyrate 4.8 mmol/L, lactic acid 0.7 mmol/L, venous pH 7.2 and base excess -16.6 mmol/L. The delta-delta gap was 10 mmol/L, compatible with a mixed anion-gap and hyperchloremic acidosis (HCA). Antibodies to GAD-65, and Zinc transporter-8 were negative. To evaluate euglycemia despite DKA, levels were obtained for serum cortisol 1 mcg/dL, and ACTH <1 pg/mL confirming secondary AI. MRI neuroimaging showed several metastatic brain lesions, a small pituitary gland without stalk enhancement or thickening. Management of euglycemic ketoacidosis required high dose glucose infusion (>10 g/hour), stress doses of hydrocortisone (HC), and infusion of low chloride solute for HCA. Conclusion Awareness of the potential for multi-endocrine dysfunction, directed us towards the urgent institution of therapy for DKA with supplementation of stress dose HC for presumed AI, the latter as a cause of relative "hypoglycemia". Central AI was confirmed with undetectable levels of cortisol and ACTH. Although less frequent than with CTLA-4 inhibitors, PD-1 inhibitors are associated with hypophysitis even without abnormalities on pituitary MRI. The DM (associated with PD-1 inhibitors) although autoimmune is nature, is "antibody" positive approximately 50% of the time. Further therapy for both euglycemic DKA and HCA required adjustment of the conventional management for DKA. To our knowledge this is the first reported case of Euglycemic DKA and secondary AI due to PD-1 inhibitors per literature review. Reference: Walters AGB, BraatvedtG G. Endocrine adverse effects of immune check point inhibitors . Intern Med J. 2021Jul;51(7): 1016-1020. doi: 10.111/imj . 14992. PMID: 34278695. Hattersley R, Nana M,Lansdown AJ. Endocrine complications of immunopathies: a review . ClinMed(Lond).2021 Mar;21(2): e212-e222. doi: 10.7861/clinmed.2020-0827. PMID: 33762389;PMCID: PMC8002767 Presentation: No date and time listed

Association of Circular RNA and Long Non-Coding RNA Dysregulation with the Clinical Response to Immune Checkpoint Blockade in Cutaneous Metastatic Melanoma.

Cutaneous melanoma (CM) is the most lethal form of skin cancer if it becomes metastatic, where treatment options and survival chances decrease dramatically. Immunotherapy treatments based on the immunologic checkpoint inhibitors programmed death cell protein 1 (PD-1) and cytotoxic T-lymphocyte antigen 4 (CTLA-4) constituted a main breakthrough in the treatment of metastatic CM, particularly for the achievement of long-term benefits. Even though it is a very promising therapy, resistance to primary immune checkpoint blockade (ICB) arises in about 70% of CM patients treated with a CTLA-4 inhibitor, and 40–65% of CM patients administered with a PD-1-targeting treatment. Some long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) are implicated in triggering pro- and anti-tumorigenic responses to various cancer treatments. The relationship between lncRNAs, circRNAs and ICB immunotherapy has not been explored in cutaneous metastatic melanoma (CMM). The aim of this pilot study is to evaluate the potential role of circRNA and lncRNA expression variability as pre-treatment predictor of the clinical response to immunotherapy in CMM patients. RNA-seq from 12 formalin-fixed paraffin-embedded (FFPE) samples from the metastatic biopsies of CMM patients treated with nivolumab was used to identify response-associated transcripts. Our findings indicate that specific lncRNAs and circRNAs, probably acting as competitive endogenous RNAs (ceRNAs), are involved in the regulatory networks of the immune response against metastatic melanoma that these patients have under treatment with nivolumab. Moreover, we established a risk score that yields predictions of the overall survival (OS) and progression-free survival (PFS) of CMM patients with high accuracy. This proof-of-principle work provides a possible insight into the function of ceRNAs, contributing to efforts to decipher the complex molecular mechanisms of ICB cancer treatment response.

Risk of Thromboembolic Events in Cancer Patients Treated with Immune Checkpoint Inhibitors: A Meta-analysis of Randomized Controlled Trials.

The association between immune checkpoint inhibitors (ICIs) and thromboembolic events (TEEs) remains controversial. The goal of this study was to assess the risk of major TEEs associated with ICIs. We explored ICI-related TEEs in randomized controlled trials available in ClinicalTrials.gov and electronic databases up to June 30, 2021. Meta-analysis was performed by using Peto odds ratios (ORs) with 95% confidence intervals (CIs). A total of 61 studies were included. Patients treated with ICIs had a similar risk of venous thromboembolism (VTE) but a significantly increased risk of arterial thromboembolism (ATE) (Peto OR: 1.58 [95% CI: 1.21-2.06]) compared with non-ICI regimens. Stratified by different regimens, only PD-L1 (programmed cell death ligand 1) inhibitors showed a significant increase in ATE (Peto OR: 2.07 [95% CI: 1.26-3.38]). The incidence of VTE was higher in PD-1/PD-L1 inhibitor and CTLA-4 (cytotoxic T lymphocyte antigen 4) inhibitor combination therapies compared with monotherapies (Peto OR: 2.23 [95% CI: 1.47-3.37]). Stratified by tumor, for pulmonary embolism (PE) and cerebral ATE, the statistically significant results were only seen in lung cancer patients (Peto OR: 1.42 [95% CI: 1.02-1.97]; Peto OR: 2.10 [1.07-4.12]), and for myocardial infarction, the statistically significant result was only seen in other tumor types (Peto OR: 2.66 [95% CI: 1.68-4.20], p < 0.0001). There was no significant increase in the overall risk of VTE in patients treated with ICIs; however, special attention should be given to the risk of VTE in PD-1/PD-L1 inhibitor and CTLA-4 inhibitor combination therapy and PE in lung cancer patients. PD-L1 inhibitors were associated with a significant increase in ATE.

Abstract #1183604: Check point inhibitor associated multi-endocrine dysfunction presenting with euglycemic ketoacidosis

Immune check point inhibitors have become breakthrough therapy for many types of cancers. They inhibit one of two immune regulatory pathways, the cytotoxic T-lymphocyte antigen 4 (CTLA-4), and ‘programmed death-1’ (PD-1) and (PD-L1) pathways. Removing immune regulation allows for anti-cancer immune responses. They also cause immune related endocrine dysfunction such as hypophysitis, thyroiditis, diabetes mellitus (DM) and primary adrenal insufficiency (AI). We describe a patient on Pembrolizumab (PEM) (an anti-PD-1 inhibitor) who presented with new onset DM, euglycemic diabetic ketoacidosis (DKA) with simultaneous secondary AI. 54-year-old woman with stage 4 non-small cell carcinoma of the lung (NSCLC) with known brain metastasis, was under therapy with carboplastin, paclitaxel and PEM, presented with headache, blurry vision and altered mental status. She had past history of Grave's disease s/p radioactive iodine therapy, currently on levothyroxine. For two weeks, she had decreased oral intake, and generalized weakness. Upon presentation, she was cachectic, BP 152/65, pulse 117 and confabulating. Laboratory evaluation showed: serum glucose 72 mg/dL, Na 139 mmol/L, K 3.2 mmol/L, Cl 113 mmol/L, HCO3 11 mmol/L, anion gap 15 mmol/L, beta-hydroxybutyrate 4.8 mmol/L, lactic acid 0.7 mmol/L, venous pH 7.2 and base excess -16.6 mmol/L. The delta-delta gap was 10 mmol/L, compatible with a mixed anion-gap and hyperchloremic acidosis (HCA). Antibodies to GAD-65, and Zinc transporter-8 were negative. To evaluate euglycemia despite DKA, levels were obtained for serum cortisol 1 mcg/dL, and ACTH < 1 pg/mL confirming secondary AI. MRI neuroimaging showed several metastatic brain lesions, a small pituitary gland without stalk enhancement or thickening. Management of euglycemic ketoacidosis required high dose glucose infusion ( >10 g/hour), stress doses of hydrocortisone (HC), and infusion of low chloride solute for HCA. Awareness of the potential multi-endocrine dysfunction, directed us towards the urgent institution of therapy for DKA with supplementation of stress dose HC for presumed AI, the latter as a cause of relative “hypoglycemia”. Central AI was confirmed with undetectable levels of cortisol and ACTH. Although less frequent than with CTLA-4 inhibitors, PD-1 inhibitors are associated with hypophysitis even without abnormalities on pituitary MRI. The DM (associated with PD-1 inhibitors) although autoimmune is nature, is “antibody” positive approximately 50% of the time. Further therapy for both euglycemic DKA and HCA required adjustment of the conventional management for DKA.

Immunotherapy in Patients with Advanced Non-Small Cell Lung Cancer Lacking Driver Mutations and Future Perspectives.

Simple SummaryThe following paper was developed as a reference for healthcare workers who are looking for information on advanced non-small cell lung cancers that lack driver mutations and their treatment with immunotherapy. The aim of the present study is to provide a reliable data source based on a review of the most current papers on the PD-1/PD-L1 and CTLA-4 inhibitors, as well as their use in medical practice.From a complete literature review, we were able to present in this paper what is most current in the treatment with immunotherapy for advanced non-small cell lung cancer (NSCLC). Especially the use of immunotherapy, particularly inhibitors of PD-1 (programmed cell death protein 1), PDL-1 (programmed cell death protein ligand 1), and CTLA-4 (cytotoxic T-lymphocyte antigen 4). Since 2015, these drugs have transformed the treatment of advanced NSCLC lacking driver mutations, evolving from second-line therapy to first-line, with excellent results. The arrival of new checkpoint inhibitors such as cemiplimab and the use of checkpoint inhibitors earlier in the therapy of advanced and metastatic cancers has been making the future prospects for treating NSCLC lacking driver mutations more favorable and optimistic. In addition, for those patients who have low PDL-1 positivity tumors, the combination of cytotoxic chemotherapy, VEGF inhibitor, and immunotherapy have shown an important improvement in global survival and progression free survival regardless the PDL-1 status. We also explored the effectiveness of adding radiotherapy to immunotherapy and the most current results about this combination. One concern that cannot be overlooked is the safety profile of immune checkpoint inhibitors (ICI) and the most common toxicities are described throughout this paper as well as tumor resistance to ICI.

Exosome CTLA-4 Regulates PTEN/CD44 Signal Pathway in Spleen Deficiency Internal Environment to Promote Invasion and Metastasis of Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common primary cancers, and its pathogenesis is complicated and difficult to screen. Currently, there is no effective treatment. In traditional Chinese medicine, a large proportion of patients with HCC have been diagnosed with spleen deficiency (SD) syndrome and treated with tonifying traditional Chinese medicine, which has significant clinical efficacy. However, the role and molecular mechanism of SD in HCC remain unclear. In this study, 40 mice were randomly divided into four groups: control, SD, HCC, and SD-HCC groups. The liver cancer model of SD was established by reserpine induction and orthotopic transplantation. The effects of SD on the proliferation, apoptosis, invasion, and metastasis of HCC cells were studied by cell proliferation, cell apoptosis, cell scratch, and transwell assay. We found that compared with the HCC group, the protein expressions of cytotoxic T lymphocyte antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), phosphatase and tensin homolog (PTEN), and AKT (also known as protein kinase B or PKB) in the exosomes of the SD-HCC group were upregulated. In addition, the metastases and self-renewal of exosomes in the SD-HCC group were more aggressive than those in the HCC group, which could be partially reversed with the addition of CTLA-4 inhibitors. Further studies showed that in the internal environment of SD, CTLA-4 promoted tumor invasion and metastasis by regulating the PTEN/CD44 pathway. In conclusion, our findings suggest that during SD in the internal environment, exosome CTLA-4 regulates the PTEN/CD44 signal pathway to promote the proliferation, self-renewal, and metastasis of liver cancer.

Spontaneous and Immune Checkpoint Inhibitor-Induced Autoimmune Diseases: Analysis of Temporal Information by Using the Japanese Adverse Drug Event Report Database.

Immune checkpoint inhibitors (ICIs) such as programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte antigen 4 (CTLA-4) inhibitors have greatly improved cancer treatment. However, they are associated with immune-related adverse events, including autoimmune diseases (ADs) owing to their immune enhancement effect. As there are few comprehensive studies of ADs by ICIs, it is necessary to analyze the period information of drug-induced ADs. We also assumed that the temporal information may be useful to estimate the similarity of the pathogenic mechanism between spontaneous and ICI-induced ADs. A period analysis including the Weibull analysis was performed on ICI-induced ADs using the Japanese Adverse Drug Event Report (JADER) database. For evaluating the similarity of spontaneous and ICI-induced ADs, a hierarchical cluster analysis was conducted to compare the different onset-time ranges. Type 1 diabetes mellitus, autoimmune colitis, and pemphigoid occurred earlier with CTLA-4 inhibitors (median: 46, 29.5 and 28 days, respectively) than with PD-1 inhibitors (> 130 days). Myasthenia gravis had a median time to onset of approximately 1 month, and the risk of onset would increase over time in ipilimumab combination therapy. This result reveals ADs that require attention. Using cluster analysis, we estimated six clusters with different patterns of onset times. Based on these results and a detailed previous research survey, the possible pathogenesis of drug-induced ADs was also discussed. This paper describes risk profiles with temporal information of ICI-induced ADs and proposes certain indicators for deciphering the mechanism of AD onset.

Systematic review with meta-analysis: safety and tolerability of immune checkpoint inhibitors in patients with pre-existing inflammatory bowel diseases.

Immune checkpoint inhibitors may variably impact patients with pre-existing autoimmune diseases. To evaluate the risks and outcomes of adverse events in patients with pre-existing inflammatory bowel diseases treated with immune checkpoint inhibitors. Through a systematic literature review up until July 31, 2020, we identified 12 studies reporting the impact of immune checkpoint inhibitors in 193 patients with inflammatory bowel disease. Outcomes of interest were relapse of inflammatory bowel disease, need for corticosteroids and/or biologics to manage inflammatory bowel disease relapse, and discontinuation of immune checkpoint inhibitors. We calculated pooled rates (with 95% confidence intervals [CI]) using random effects meta-analysis, and examined risk factors associated with adverse outcomes through qualitative synthesis of individual studies. On meta-analysis, 40% patients (95% CI, 26%-55%) experienced relapse of inflammatory bowel disease with immune checkpoint inhibitors. Among patients who experienced relapse, 76% (95% CI, 65%-85%) required corticosteroids, and 37% (95% CI, 22%-53%) required biologic therapy. Overall, 35% patients (95% CI, 17%-57%) with inflammatory bowel disease discontinued immune checkpoint inhibitors. Gastrointestinal perforation and abdominal surgery due to immune checkpoint inhibitor complications occurred in <5% patients. In a large study, inhibitors of cytotoxic T-lymphocyte antigen-4 (CTLA-4) were associated with a higher risk of relapse than programmed cell death 1 (PD-1) and programmed death ligand 1 (PD-L1) inhibitors. Approximately 40% of patients with pre-existing inflammatory bowel diseases experience relapse with immune checkpoint inhibitors, with most relapsing patients requiring corticosteroids and one-third requiring biologics. CTLA-4 inhibitors may be associated with higher risk of relapse.

Pilot Study of CT-Based Radiomics Model for Early Evaluation of Response to Immunotherapy in Patients With Metastatic Melanoma.

Objective: Determine the performance of a computed tomography (CT) -based radiomics model in predicting early response to immunotherapy in patients with metastatic melanoma.Methods: This retrospective study examined 50 patients with metastatic melanoma who received immunotherapy treatment in our hospital with an anti-programmed cell death-1 (PD-1) agent or an inhibitor of cytotoxic T lymphocyte antigen-4 (CTLA-4). Thirty-four patients who received an anti-PD-1 agent were in the training sample and 16 patients who received a CTLA-4 inhibitor were in the validation sample. Patients with true progressive disease (PD) were in the poor response group, and those with pseudoprogression, complete response (CR), partial response (PR), or stable disease (SD) were in the good response group. CT images were examined at baseline and after the first and second cycles of treatment, and the imaging data were extracted for radiomics modeling.Results: The radiomics model based on pre-treatment, post-treatment, and delta features provided the best results for predicting response to immunotherapy. Receiver operating characteristic (ROC) analysis for good response indicated an area under the curve (AUC) of 0.882 for the training group and an AUC of 0.857 for the validation group. The sensitivity, specificity, and accuracy of model were 85.70% (6/7), 66.70% (6/9), and 75% (12/16) for predicting a good response.Conclusion: A CT-based radiomics model for metastatic melanoma has the potential to predict early response to immunotherapy and to identify pseudoprogression.

Immune checkpoint inhibitor induced autoimmune encephalitis in a patient with metastatic melanoma

Background: Immune checkpoint inhibitors have changed the therapeutic milieu for patients with metastatic melanoma. However, their use may promote autoimmunity in virtually any organ in the body due to the blockade of intrinsic immune down regulators such as cytotoxic T-lymphocyte antigen- 4 (CTLA-4), programmed cell death 1 (PD1) or its ligand (PDL1). Immune mediated adverse neurological events are rare with these agents, however, and are seen in &lt; 1% of treated patients. We report a patient with immune checkpoint inhibitor associated autoimmune encephalitis, with complete clinical recovery after treatment.Case Report: A 49-year-old female with metastatic melanoma currently on nivolumab therapy but recently on ipilimumab/nivolumab combined therapy presented with a new headache. She also reported associated confusion, loss of balance, personality changes and language difficulty. Magnetic resonance imaging of the brain did not reveal any evidence of metastasis, infarct, meningitis, or encephalitis. Lumbar puncture revealed an elevated protein level and pleocytosis, with a normal glucose level. She was started on empiric glucocorticoid therapy with a presumptive diagnosis of immune checkpoint inhibitor associated autoimmune encephalitis. She improved considerably by day 3 of treatment with complete resolution of neurological symptoms by day 5.Conclusion: Immune checkpoint inhibitors are increasingly important in cancer immunotherapy as they can cause sustained remissions in patients with metastatic melanoma and other malignancies. Because these drugs block immune-regulatory targets, they can lead to enhanced activation of immune system resulting in immune-related adverse events. Autoimmune encephalitis is a rare immune-related adverse event associated with immune checkpoint inhibitors. The incidence of autoimmune encephalitis is higher with combination or sequential CTLA-4 (ipilimumab) and PD1(nivolumab) inhibitor therapy than with monotherapy. With more widespread use of immunotherapy, it is important for clinicians to be aware of this rare and reversible cause of encephalitis. Early recognition and prompt initiation of immunosuppressive therapy with glucocorticoids is essential to enhance neurological recovery.

SAT-239 Combination of Immune Check Point Inhibitors Causing Hypopituitarism

Introduction: Immune Check Point inhibitors (ICI) have been associated with immune related adverse events including a wide array of Endocrinopathies particularly when a combination of ICIs is used. We present a case of Hypopituitarism secondary to CTLA-4 inhibitor Iplimumab and PD-1 inhibitor Pembrulizumab in a patient with Vulvar Melanoma.Case Description: 49-year-old female with past medical history of Type 2 Diabetes and Vulvar Melanoma presented with nausea, vomiting and fatigue. The patient had surgical excision of Vulvular Melanoma and had been on chemotherapy with Pembrolizumab and Ipilimumab for 1 month. She was found to be hypotensive in the ER, but blood pressure improved after fluid resuscitation. Her blood sugar levels were 76 MG/DL. She denied using any insulin in the last 24 hours. AM Cortisol was <1 UG/ML. TSH was 0.205 UIU/ML with free T4 at 0.74 NG/DL. FSH was 2.5 MIU/ML. LH was 0.5 MIU/ML. Prolactin was 90.2 NG/ML. ACTH was less than 9 PG/ML. MRI of the brain showed mildly enlarged pituitary gland with suprasellar extension, measuring 10.5 mm in craniocaudal height and normal homogeneous enhancement. A diagnosis of Hypopituitarism secondary Ipilimumab and Pembrolizumab was made. She was started on steroids and thyroid replacement. The patient’s symptoms resolved, and she was discharged home in a stable condition with outpatient Endocrinology follow up.Discussion: Immune checkpoint inhibitors (ICI) includes PD1(Programmed cell death receptor 1) inhibitors like Pembrolizumab and CTLA-4 (Cytotoxic T Lymphocyte Antigen-4) inhibitors like Ipilimumab. CTLA-4 inhibitors have more frequently been associated with Hypophysitis leading to particularly ACTH and TSH deficiencies and causing secondary adrenal insufficiency and secondary hypothyroidism. Posterior Pituitary involvement is less common. MRI usually shows mild to moderate enlargement of the pituitary gland. ICI therapy usually does not need to be stopped. Patients commonly require long term glucocorticoid and thyroid replacement.

Thyroid Toxicity Following Immune Checkpoint Inhibitor Treatment in Advanced Cancer.

Background: Inhibitory antibodies against cytotoxic T lymphocyte antigen-4 (CTLA-4) and programmed cell death-1 (PD-1) have antitumor efficacy and are now standard of care in the management of multiple cancer subtypes. However, the use is complicated by the development of autoimmunity, which can occur in multiple organ systems. Thyroiditis is the most common immune-related adverse event. Summary: Immune checkpoint inhibitor (ICI)-associated thyroiditis affects over 10% of treated patients. PD-1 inhibitors are associated with greater risk of thyroid dysfunction relative to CTLA-4 inhibitors, although the highest risk occurs with combined anti-CTLA-4 and anti-PD-1 treatment. Onset is typically rapid, within weeks to months and both hyperthyroidism and hypothyroidism can occur. The most frequent pattern of thyroid dysfunction is transient hyperthyroidism with evolution to hypothyroidism over four to six weeks. Most cases are asymptomatic and resolve without dedicated treatment. There is no sex or age predominance, and predictive risk factors have not been reliably identified. Thyroid autoantibodies are variably present and are not clearly related to the risk or progression of thyroid dysfunction following treatment with an ICI. Observational data suggest that development of ICI-associated thyroiditis may predict improved survival. Conclusions: ICI-associated thyroiditis is a distinct clinical entity. Mechanisms underlying etiology remain largely unknown. Awareness among health professionals is important to limit morbidity and avoid unnecessary periods of untreated hypothyroidism.

Are immune-related adverse events associated with the efficacy of immune checkpoint inhibitors in patients with cancer? A systematic review and meta-analysis

BackgroundA number of studies have reported an association between the occurrence of immune-related adverse events (irAEs) and clinical efficacy in patients undergoing treatment with immune checkpoint inhibitors (ICIs), but the results remain controversial.MethodsUnder the guidance of a predefined protocol and Preferred Reporting Items for Systematic Reviews and Meta-analyses statement, this meta-analysis included cohort studies investigating the association of irAEs and efficacy of ICIs in patients with cancer. The primary outcome was overall survival (OS), and the secondary outcome was progression-free survival (PFS). Subgroup analyses involving the cancer type, class of ICIs, combination therapy, sample size, model, landmark analysis, and approach used to extract the data were performed. Specific analyses of the type and grade of irAEs were also performed.ResultsThis meta-analysis included 30 studies including 4971 individuals. Patients with cancer who developed irAEs experienced both an OS benefit and a PFS benefit from ICI therapy compared to patients who did not develop irAEs (OS: hazard ratio (HR), 0.54, 95% confidence interval (CI), 0.45–0.65; p < 0.001; PFS: HR, 0.52, 95% CI, 0.44–0.61, p < 0.001). Subgroup analyses of the study quality characteristics and cancer types recapitulated these findings. Specific analyses of endocrine irAEs (OS: HR, 0.52, 95% CI, 0.44–0.62, p < 0.001), dermatological irAEs (OS: HR, 0.45, 95% CI, 0.35–0.59, p < 0.001), and low-grade irAEs (OS: HR, 0.57, 95% CI, 0.43–0.75; p < 0.001) yielded similar results. The association between irAE development and a favorable benefit on survival was significant in patients with cancer who were undergoing treatment with programmed cell death-1 inhibitors (OS: HR, 0.51, 95% CI, 0.42–0.62; p < 0.001), but not cytotoxic T-lymphocyte antigen-4 inhibitors (OS: HR, 0.89, 95% CI, 0.49–1.61; p = 0.706). Additionally, the association was significant in patients with cancer who were treated with ICIs as a monotherapy (OS: HR, 0.53, 95% CI, 0.43–0.65; p < 0.001), but not as a combination therapy (OS: HR, 0.62, 95% CI, 0.36–1.05; p = 0.073).ConclusionsThe occurrence of irAEs was significantly associated with a better ICI efficacy in patients with cancer, particularly endocrine, dermatological, and low-grade irAEs. Further large-scale prospective studies are warranted to validate our findings.Systematic review registrationPROSPERO CRD42019129310.

Hyponatremia in a Patient With Cancer

Hyponatremia in a Patient With Cancer

Extraocular Muscle Enlargement and Thyroid Eye Disease-like Orbital Inflammation Associated with Immune Checkpoint Inhibitor Therapy in Cancer Patients

To describe thyroid eye disease (TED)-like orbital inflammatory syndrome in 3 cancer patients treated with immune checkpoint inhibitors. All consecutive patients treated by the senior author who were receiving immune checkpoint inhibitors and developed TED-like orbital inflammation were included. Three cancer patients treated with immune checkpoint inhibitors developed orbital inflammation. The first patient was treated with a combination of a cytotoxic T-lymphocyte antigen-4 inhibitor and a programmed cell death protein 1 inhibitor and developed TED-like orbital inflammation with normal thyroid function and antibody levels. The second patient had a previous diagnosis of Graves disease without TED, and developed TED soon after initiating treatment with a programmed cell death protein 1 inhibitor. The third patient developed acute hyperthyroidism with symptomatic TED following treatment with an investigational cytotoxic T-lymphocyte antigen-4 inhibitor agent. All 3 patients were managed with either systemic steroids or observation, with resolution of their symptoms and without the need to halt immune checkpoint inhibitor treatment for their cancer. TED-like orbital inflammation may occur as a side effect of immune checkpoint inhibitor therapy with anti-cytotoxic T-lymphocyte antigen-4 or anti-PD-1 inhibitors. To the best of their knowledge, this is the first reported case of TED as a result of programmed cell death protein 1 inhibitor monotherapy. All 3 patients were treated with systemic steroids and responded quickly while continuing treatment with immune checkpoint inhibitors for their cancer. With increasing use of this class of drugs, clinicians should be familiar with the clinical manifestations and treatments for this adverse reaction.

Gastrointestinal adverse events with combination of checkpoint inhibitors in advanced melanoma: a systematic review.

Introduction:Immunotherapies, including checkpoint inhibitors (CIs) such as cytotoxic T-lymphocyte antigen-4 (CTLA-4) and programmed death-1 (PD-1) inhibitors, are revolutionizing the treatment of advanced melanoma. Combining CTLA-4 and PD-1 inhibitors provides additional clinical benefit compared with single agents alone. However, combination therapy can increase the incidence of gastrointestinal adverse events (GI AEs). This systematic review assessed the epidemiological, clinical, economic, and humanistic burden of GI AEs due to combination CIs in advanced melanoma.Methods:MEDLINE, EMBASE, and the Cochrane Library were systematically searched (December 2011 to December 2016) to identify primary studies, systematic reviews, meta-analyses, and conference proceedings (2014–2016) evaluating adults treated with ≥2 CIs for advanced melanoma.Results:Of the 3391 identified articles, 14 were included. Most studies examined the ipilimumab plus nivolumab combination. Any grade and grade 3–4 GI AEs occurred in more patients receiving ipilimumab plus nivolumab versus ipilimumab or nivolumab alone. The most common grade 3–4 GI AEs were diarrhea and colitis. Grade 3–4 colitis occurred in more patients receiving ipilimumab plus nivolumab. However, grade 3–4 diarrhea occurred at the same rate as ipilimumab alone. GI AEs developed with ipilimumab plus nivolumab approximately 6.6 weeks after initiating treatment. No studies assessing the economic or humanistic burden of GI AEs were identified.Conclusion:GI AEs occurred at a higher rate and greater severity in patients treated with ipilimumab plus nivolumab versus ipilimumab or nivolumab monotherapy. The lack of research on economic and humanistic burden of GI AEs with combination CIs for advanced melanoma represents an unmet need in the literature and should be explored in future studies.

Adjuvanticity of a CTLA-4 3′ UTR complementary oligonucleotide for emulsion formulated recombinant subunit and inactivated vaccines

Cytotoxic T-lymphocyte antigen 4 (CTLA-4) is recognized as a critical inhibitory regulator of T-cell proliferation and activation, opposing the action of CD28-mediated co-stimulation. Interfering or blocking CTLA-4 can result in continuous T-cell activation required for the full immune response to pathogenic microbes and vaccines. To test if nucleic acid-based CTLA-4 inhibitors could be developed into a novel adjuvant, we designed two oligonucleotides, CMD-1 and CMD-2, with the sequences complementary to the conserve regions identical between human and mouse CTLA-4 mRNA 3′ untranslated region (3′ UTR), and tested their in vitro effects on CTLA-4 production and their adjuvanticity for vaccines in mice. We found that CMD-1 inhibited the antigen-induced CTLA-4 up-regulation on the CD4+ T cells by interfering its mRNA expression, maintained higher levels of CD80 and CD86 on the CD11c+ cells and promoted the recalled proliferation of the CD4+ T cells and CD19+ B cells, and that the CMD-1 enhanced the antibody response against recombinant PCV2b capsid protein or inactivated foot-and-mouth disease virus in both ICR and BALB/c mice. These data suggest that the CMD-1 could be used as a novel vaccine adjuvant capable of inhibiting inhibitory signals rather than inducing stimulatory signals of immune cells.

Melanoma Immunotherapy: Mechanisms and Opportunities

Immune checkpoint blockade via inhibition of Cytotoxic T Lymphocyte Antigen 4 (CTLA-4) and Programmed Cell Death 1 Receptor (PD-1) has demonstrated significant clinical benefits in treating melanoma and other types of cancers and has since become a very progressive field in cancer research. Despite durable tumor regression observed in some patients, response rates to CTLA-4 and PD-1 still have room for improvement. There are many additional immune modulatory pathways, including inhibitory molecules expressed on tumor cells and secretion of pro-inflammatory cytokines by lymphatic cells that could potentially be targeted to enhance the anti-tumor responses to PD-1 and CTLA-4. Here, we review the current status of CTLA-4 and PD-1 inhibitors in the treatment of melanoma and several therapeutic targets and strategies that may synergize with checkpoint blockades.