scholarly journals Structure and Optimization of Checkpoint Inhibitors

Cancers ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 38 ◽  
Author(s):  
Sarah L. Picardo ◽  
Jeffrey Doi ◽  
Aaron R. Hansen

With the advent of checkpoint inhibitor treatment for various cancer types, the optimization of drug selection, pharmacokinetics and biomarker assays is an urgent and as yet unresolved dilemma for clinicians, pharmaceutical companies and researchers. Drugs which inhibit cytotoxic T-lymphocyte associated protein-4 (CTLA-4), such as ipilimumab and tremelimumab, programmed cell death protein-1 (PD-1), such as nivolumab and pembrolizumab, and programmed cell death ligand-1 (PD-L1), such as atezolizumab, durvalumab and avelumab, each appear to have varying pharmacokinetics and clinical activity in different cancer types. Each drug differs in terms of dosing, which becomes an issue when drug comparisons are attempted. Here, we examine the various checkpoint inhibitors currently used and in development. We discuss the antibodies and their protein targets, their pharmacokinetics as measured in various tumor types, and their binding affinities to their respective antigens. We also examine the various dosing regimens for these drugs and how they differ. Finally, we examine new developments and methods to optimize delivery and efficacy in the field of checkpoint inhibitors, including non-fucosylation, prodrug formations, bispecific antibodies, and newer small molecule and peptide checkpoint inhibitors.

2018 ◽  
Vol 12 ◽  
pp. 175346581775007 ◽  
Author(s):  
Prantesh Jain ◽  
Chhavi Jain ◽  
Vamsidhar Velcheti

Immune checkpoint inhibitors, mainly drugs targeting the programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) and cytotoxic T-lymphocyte antigen 4 (CTLA4) pathways, represent a remarkable advance in lung cancer treatment. Immune checkpoint inhibitors targeting PD-1 and PD-L1 are approved for the treatment of patients with non-small-cell lung cancer, with impressive clinical activity and durable responses in some patients. This review will summarize the mechanism of action of these drugs, the clinical development of these agents and the current role of these agents in the management of patients with lung cancer. In addition, the review will discuss the role of predictive biomarkers for optimal patient selection for immunotherapy and management of autoimmune side effects of these agents.


Author(s):  
Barbara Barnes Rogers, CRNP, MN, AOCN, ANP-BC ◽  
Carolyn Zawislak, MPAS, PA-C ◽  
Victoria Wong, PA-C

Immune checkpoint inhibitors target suppressor receptors, including cytotoxic T-lymphocyte–associated antigen 4 (CTLA-4), programmed cell death protein 1 (PD-1), and programmed cell death ligand 1 (PD-L1). The activated T cells are not antigen specific; therefore, the blockade of the immune checkpoint may result in the development of autoimmune adverse events. The most common immune-related adverse events (irAEs) are rash, colitis, and endocrinopathies. However, irAEs that affect the hematologic system are rare and can affect red blood cells (e.g., autoimmune hemolytic anemia), white blood cells, and platelets (e.g., immune thrombocytopenia). Usually one cell line is affected; however, in some cases, multiple cell lines can be affected. Other changes in the hematologic system can also be affected (e.g., cryoglobulinemia, cytokine release syndrome). Due to the rarity and lack of recognition of these AEs, the timing, spectrum of events, and clinical presentation are poorly understood. Management of hematologic irAEs usually involves the use of steroids; however, other agents (e.g., IVIG, cyclosporine, rituximab) or procedures (e.g., plasma exchange, transfusions) can also be used.


2016 ◽  
Vol 157 (Supplement 2) ◽  
pp. 9-16 ◽  
Author(s):  
Szilvia Szamosi ◽  
László Váróczy ◽  
Zoltán Szekanecz

In the past decade major advances in tumor immunology, a better understanding of antigen recognition by T-cells likewise discovering the regulatory inhibitory signals resulted in the development of new immunotherapies with promising durable responses in various solid tumor types and in hematologic malignancies. This review focuses on immunomodulatory antibodies, namely immune checkpoint inhibitor therapy. The prototype of this new class of immune stimulating agents was cytotoxic T-lymphocyte antigen-4 (CTLA-4) antagonists. After demonstrating enhanced survival, ipilimumab was approved first in the United States in 2011, further on in the European Union for second-line (2011) and for first-line therapy (2013) of metastatic melanoma. Additional T-cell intrinsic pathways were identified and targeted for clinical development. Antibodies blocking the PD-1 pathway also showed promising clinical activity and objective tumor response in several types of tumors, including metastatic melanoma, non-small- cell lung cancer. On the other hand antitumor activity is frequently accompanied by significant reversible immune-related adverse events. To explore potential new immune checkpoint targets bring forth several challanges. Future clinical development will involve identifying potential biomarkers anticipating responsiveness to pathway blockade and additional tumor types likely to respond to the therapy. Furthermore, combination strategies, immune checkpoint inhibitors combined with cancer vaccines, targeted inhibitors and traditional chemotherapies are being evaluated in pre-clinical studies. Orv. Hetil., 2016, 157(Suppl. 2), 9–16.


Author(s):  
Nádia Ghinelli Amôr ◽  
Paulo Sérgio da Silva Santos ◽  
Ana Paula Campanelli

Squamous cell carcinoma (SCC) is the second most common skin cancer worldwide and, despite the relatively easy visualization of the tumor in the clinic, a sizeable number of SCC patients are diagnosed at advanced stages with local invasion and distant metastatic lesions. In the last decade, immunotherapy has emerged as the fourth pillar in cancer therapy via the targeting of immune checkpoint molecules such as programmed cell-death protein-1 (PD-1), programmed cell death ligand-1 (PD-L1), and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4). FDA-approved monoclonal antibodies directed against these immune targets have provide survival benefit in a growing list of cancer types. Currently, there are two immunotherapy drugs available for cutaneous SCC: cemiplimab and pembrolizumab; both monoclonal antibodies (mAb) that block PD-1 thereby promoting T-cell activation and/or function. However, the success rate of these checkpoint inhibitors currently remains around 50%, which means that half of the patients with advanced SCC experience no benefit from this treatment. This review will highlight the mechanisms by which the immune checkpoint molecules regulate the tumor microenvironment (TME), as well as the ongoing clinical trials that are employing single or combinatory therapeutic approaches for SCC immunotherapy. We also discuss the regulation of additional pathways that might promote superior therapeutic efficacy, and consequently provide increased survival for those patients that do not benefit from the current checkpoint inhibitor therapies.


BMJ ◽  
2020 ◽  
pp. m736 ◽  
Author(s):  
Karmela K Chan ◽  
Anne R Bass

Abstract Immune checkpoint inhibitors (ICIs) are monoclonal antibodies that target inhibitory molecules, such as cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), programmed cell death protein 1 (PD-1), or its ligand, programmed cell death protein ligand 1 (PD-L1), and lead to immune activation in the tumor micro-environment. ICIs can induce durable treatment responses in patients with advanced cancers, but they are commonly associated with immune related adverse events (irAEs) such as rash, colitis, hepatitis, pneumonitis, and endocrine and musculoskeletal disorders. Almost all patients experience some form of irAE, but high grade irAEs occur in approximately half of those on combination therapy (eg, anti-CTLA-4 plus anti-PD-1), and up to one quarter receiving ICI monotherapy. Fatal irAEs occur in approximately 1.2% of patients on CTLA-4 blockade and 0.4% of patients receiving PD-1 or PD-L1 blockade, and case fatality rates are highest for myocarditis and myositis. IrAEs typically occur in the first three months after ICI initiation, but can occur as early as one day after the first dose to years after ICI initiation. The mainstay of treatment is with corticosteroids, but tumor necrosis factor inhibitors are commonly used for refractory irAEs. Although ICIs are generally discontinued when high grade irAEs occur, ICI discontinuation alone is rarely adequate to resolve irAEs. Consensus guidelines have been published to help guide management, but will likely be modified as our understanding of irAEs grows.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Julian A. Marin-Acevedo ◽  
ErinMarie O. Kimbrough ◽  
Yanyan Lou

AbstractThe immune system is the core defense against cancer development and progression. Failure of the immune system to recognize and eliminate malignant cells plays an important role in the pathogenesis of cancer. Tumor cells evade immune recognition, in part, due to the immunosuppressive features of the tumor microenvironment. Immunotherapy augments the host immune system to generate an antitumor effect. Immune checkpoints are pathways with inhibitory or stimulatory features that maintain self-tolerance and assist with immune response. The most well-described checkpoints are inhibitory in nature and include the cytotoxic T lymphocyte-associated molecule-4 (CTLA-4), programmed cell death receptor-1 (PD-1), and programmed cell death ligand-1 (PD-L1). Molecules that block these pathways to enhance the host immunologic activity against tumors have been developed and become standard of care in the treatment of many malignancies. Only a small percentage of patients have meaningful responses to these treatments, however. New pathways and molecules are being explored in an attempt to improve responses and application of immune checkpoint inhibition therapy. In this review, we aim to elucidate these novel immune inhibitory pathways, potential therapeutic molecules that are under development, and outline particular advantages and challenges with the use of each one of them.


Author(s):  
Lavanya Kondapalli ◽  
Theresa Medina ◽  
Daniel W Groves

Abstract Immuno-oncology employs various therapeutic strategies that harness a patient’s own immune system to fight disease and has been a promising new strategy for cancer therapy over the last decade. Immune checkpoint inhibitors (ICI), are monoclonal antibodies, that increase antitumor immunity by blocking intrinsic down-regulators of immunity, such as cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death 1 (PD-1) or its ligand, programmed cell death ligand 1 (PD-L1). Seven ICIs are currently approved by the Food and Drug Administration and have increased the overall survival for patients with various cancer subtypes. These are used either as single agents or in combination with other checkpoint inhibitors, small molecular kinase inhibitors or cytotoxic chemotherapies. There are also many other immune modifying agents including other checkpoint inhibitor antibodies that are under investigation in clinical trials.


2018 ◽  
Vol 71 (8) ◽  
pp. 665-671 ◽  
Author(s):  
Dipti M Karamchandani ◽  
Runjan Chetty

Immune checkpoint inhibitors (CPIs) are a relatively new class of ‘miracle’ dugs that have revolutionised the treatment and prognosis of some advanced-stage malignancies, and have increased the survival rates significantly. This class of drugs includes cytotoxic T lymphocyte antigen-4 inhibitors such as ipilimumab; programmed cell death protein-1 inhibitors such as nivolumab, pembrolizumab and avelumab; and programmed cell death protein ligand-1 inhibitors such as atezolizumab. These drugs stimulate the immune system by blocking the coinhibitory receptors on the T cells and lead to antitumoural response. However, a flip side of these novel drugs is immune-related adverse events (irAEs), secondary to immune-mediated process due to disrupted self-tolerance. The irAEs in the gastrointestinal (GI) tract/liver may result in diarrhoea, colitis or hepatitis. An accurate diagnosis of CPI-induced colitis and/or hepatitis is essential for optimal patient management. As we anticipate greater use of these drugs in the future given the significant clinical response, pathologists need to be aware of the spectrum of histological findings that may be encountered in GI and/or liver biopsies received from these patients, as well as differentiate them from its histopathological mimics. This present review discusses the clinical features, detailed histopathological features, management and the differential diagnosis of the luminal GI and hepatic irAEs that may be encountered secondary to CPI therapy.


Biomedicines ◽  
2021 ◽  
Vol 9 (10) ◽  
pp. 1484
Author(s):  
Hiroyuki Ando ◽  
Kunihiro Suzuki ◽  
Toyoshi Yanagihara

Immune-checkpoint inhibitors (ICIs) targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4), programmed cell death-1 (PD-1), and programmed cell death-1-ligand 1 (PD-L1) have become new treatment options for various malignancies. ICIs bind to immune-checkpoint inhibitory receptors or to the foregoing ligands and block inhibitory signals to release the brakes on the immune system, thereby enhancing immune anti-tumor responses. On the other hand, unlike conventional chemotherapies, ICIs can cause specific side effects, called immune-related adverse events (irAEs). These toxicities may affect various organs, including the lungs. ICI-related pneumonitis (ICI-pneumonitis) is not the most frequent adverse event, but it is serious and can be fatal. In this review, we summarize recent findings regarding ICI-pneumonitis, with a focus on potential pathogenesis and treatment.


2017 ◽  
Vol 103 (2) ◽  
pp. 365-369 ◽  
Author(s):  
Chen Zhao ◽  
Sri Harsha Tella ◽  
Jaydira Del Rivero ◽  
Anuhya Kommalapati ◽  
Ifechukwude Ebenuwa ◽  
...  

Abstract Context Immune checkpoint inhibitors, including anti–programmed cell death protein 1 (PD-1), anti–programmed cell death protein ligand 1 (PD-L1), and anti–cytotoxic T-lymphocyte antigen 4 (anti-CTLA4) monoclonal antibodies, have been widely used in cancer treatment. They are known to cause immune-related adverse events (irAEs), which resemble autoimmune diseases. Anterior pituitary hypophysitis with secondary hypopituitarism is a frequently reported irAE, especially in patients receiving anti–CTLA4 treatment. In contrast, posterior pituitary involvement, such as central diabetes insipidus (DI), is relatively rare and is unreported in patients undergoing PD-1/PD-L1 blockade. Case Description We describe a case of a 73-year-old man with Merkel cell carcinoma who received the anti–PD-L1 monoclonal antibody avelumab and achieved partial response. The patient developed nocturia, polydipsia, and polyuria 3 months after starting avelumab. Further laboratory testing revealed central DI. Avelumab was held and he received desmopressin for the management of central DI. Within 6 weeks after discontinuation of avelumab, the patient’s symptoms resolved and he was eventually taken off desmopressin. The patient remained off avelumab and there were no signs or symptoms of DI 2 months after the discontinuation of desmopressin. Conclusion To our knowledge, this is the first report of central DI associated with anti–PD-L1 immunotherapy. The patient’s endocrinopathy was successfully managed by holding treatment with the immune checkpoint inhibitor. This case highlights the importance of early screening and appropriate management of hormonal irAEs in subjects undergoing treatment with immune checkpoint inhibitors to minimize morbidity and mortality.


Sign in / Sign up

Export Citation Format

Share Document