Advances In Cancer Immunotherapy Research Articles

CIMT 2021: report on the 18th Annual Meeting of the Association for Cancer Immunotherapy

ABSTRACT After one year of absence, the 18th Annual Meeting of the Association for Cancer Immunotherapy (CIMT), Europe’s cancer immunotherapy meeting, took place virtually from 10 to 12 May 2021. Over 850 academic and clinical professionals from 30 countries met to discuss the recent advancements in cancer immunotherapy and the current progress in COVID19-related research. This meeting report summarizes the highlights of CIMT2021.

Surface glycan targeting for cancer nano-immunotherapy

Cancer immunotherapy is an emerging therapeutic strategy for cancer treatment. Most of the immunotherapeutics approved by the FDA regulate the innate immune system and associated immune cell activity, with immune check inhibitors in particular having transformed the field of cancer immunotherapy due to their significant clinical potential. However, previously reported immunotherapeutics have exhibited undesirable side effects, including autoimmune toxicity and inflammation. Controlling these deleterious responses and designing therapeutics that can precisely target specific regions are thus crucial to improving the efficacy of cancer immunotherapies. Recent studies have reported that cancer cells employ glycan−immune checkpoint interactions to modulate immune cell activity. Thus, the recognition of cancer glycan moieties such as sialoglycans may improve the anticancer activity of immune cells. In this review, we discuss recent advances in cancer immunotherapies involving glycans and glycan-targeting technologies based on nanomaterial-assisted local delivery systems.

A Comprehensive Review of Recent Advancements in Cancer Immunotherapy and Generation of CAR T Cell by CRISPR-Cas9

The mechanisms involved in immune responses to cancer have been extensively studied for several decades, and considerable attention has been paid to harnessing the immune system’s therapeutic potential. Cancer immunotherapy has established itself as a promising new treatment option for a variety of cancer types. Various strategies including cancer vaccines, monoclonal antibodies (mAbs), adoptive T-cell cancer therapy and CAR T-cell therapy have gained prominence through immunotherapy. However, the full potential of cancer immunotherapy remains to be accomplished. In spite of having startling aspects, cancer immunotherapies have some difficulties including the inability to effectively target cancer antigens and the abnormalities in patients’ responses. With the advancement in technology, this system has changed the genome-based immunotherapy process in the human body including the generation of engineered T cells. Due to its high specificity, CRISPR-Cas9 has become a simple and flexible genome editing tool to target nearly any genomic locus. Recently, the CD19-mediated CAR T-cell (chimeric antigen receptor T cell) therapy has opened a new avenue for the treatment of human cancer, though low efficiency is a major drawback of this process. Thus, increasing the efficiency of the CAR T cell (engineered T cells that induce the chimeric antigen receptor) by using CRISPR-Cas9 technology could be a better weapon to fight against cancer. In this review, we have broadly focused on recent immunotherapeutic techniques against cancer and the use of CRISPR-Cas9 technology for the modification of the T cell, which can specifically recognize cancer cells and be used as immune-therapeutics against cancer.

Algorithmic asymptotic analysis: Extending the arsenal of cancer immunology modeling

The recent advances in cancer immunotherapy boosted the development of tumor-immune system models, with the aim to indicate more efficient treatments. Physical understanding is however difficult to be acquired, due to the complexity and the multi-scale dynamics of these models. In this work, the dynamics of a fundamental model formulating the interactions of tumor cells with natural killer cells, CD8+ T cells and circulating lymphocytes is examined. It is first shown that the long-term evolution of the system towards high-tumor or tumor-free equilibria is determined by the dynamics of an initial explosive stage of tumor progression. Focusing on this stage, the algorithmic Computational Singular Perturbation methodology is employed to identify the underlying mechanisms confining the system’s evolution and the governing slow dynamics along them. These insights are preserved along different tumor-immune system and patient-dependent realizations. On top of these identifications, a novel reduced model is algorithmically constructed, which accurately predicts the dynamics of the system during the explosive stage and includes half of the parameters of the detailed model. The present analysis demonstrates the potential of algorithmic asymptotic analysis for acquiring physical understanding and for simplifying the complexity of cancer immunology models. Along with the current techniques on the field, this analysis can provide guidelines for more effective treatment development.

Going with the Flow: Modeling the Tumor Microenvironment Using Microfluidic Technology.

Simple SummaryThe clinical success of cancer immunotherapy targeting immune checkpoints (e.g., PD-1, CTLA-4) has ushered in a new era of cancer therapeutics aimed at promoting antitumor immunity in hopes of offering durable clinical responses for patients with advanced, metastatic cancer. This success has also reinvigorated interest in developing tumor model systems that recapitulate key features of antitumor immune responses to complement existing in vivo tumor models. Patient-derived tumor models have emerged in recent years to facilitate study of tumor–immune dynamics. Microfluidic technology has enabled development of microphysiologic systems (MPSs) for the evaluation of the tumor microenvironment, which have shown early promise in studying tumor–immune dynamics. Further development of microfluidic-based “tumor-on-a-chip” MPSs to study tumor–immune interactions may overcome several key challenges currently facing tumor immunology.Recent advances in cancer immunotherapy have led a paradigm shift in the treatment of multiple malignancies with renewed focus on the host immune system and tumor–immune dynamics. However, intrinsic and acquired resistance to immunotherapy limits patient benefits and wider application. Investigations into the mechanisms of response and resistance to immunotherapy have demonstrated key tumor-intrinsic and tumor-extrinsic factors. Studying complex interactions with multiple cell types is necessary to understand the mechanisms of response and resistance to cancer therapies. The lack of model systems that faithfully recapitulate key features of the tumor microenvironment (TME) remains a challenge for cancer researchers. Here, we review recent advances in TME models focusing on the use of microfluidic technology to study and model the TME, including the application of microfluidic technologies to study tumor–immune dynamics and response to cancer therapeutics. We also discuss the limitations of current systems and suggest future directions to utilize this technology to its highest potential.

Confirmed complete response to nivolumab for advanced gastric cancer with peritoneal dissemination: a case report

BackgroundRecent advances in cancer immunotherapy have been remarkable, with many reports on the clinical effects of immune checkpoint inhibitors. Nivolumab has been covered by the national health insurance in Japan as a third-line agent for advanced and recurrent gastric cancer since September 2017. The objective response rate for nivolumab for gastric cancer is 11.2%. However, patients’ quality of life during this treatment has not been examined. Here, we report a case in which multidisciplinary treatment, including with nivolumab, resulted in long-term survival and improved quality of life.Case presentationA 70-year-old Asian woman was referred for surgery for gastric cancer. Postoperative pathological examination revealed peritoneal dissemination, and the patient was diagnosed with stage IV gastric cancer. Therefore, she was treated with S-1 and cisplatin based on negative immunohistochemical staining of resected specimens for human epidermal growth factor receptor 2. However, owing to instability and adverse events, treatment was subsequently changed to S-1 monotherapy. Two years after changing to S-1 monotherapy, she developed recurrence of peritoneal dissemination and was treated with docetaxel. Radiation therapy was also used because the recurrent lesions were local. However, 6 months later, new peritoneal dissemination and lymph node metastasis were observed and nivolumab was started. Subsequent abdominal computed tomography revealed a marked reduction in the disseminated nodules and lymphadenopathy. After 54 cycles of nivolumab, the lesions had disappeared completely. The patient has not developed side effects, including immune-responsive adverse events, has improved quality of life, and is returning to work. She is currently taking nivolumab, and there is no evidence of recurrence approximately 3 years after starting nivolumab.ConclusionsNivolumab may have beneficial effects in some patients with advanced or recurrent gastric cancer. Although the prognosis for gastric cancer and peritoneal dissemination is poor, multidisciplinary treatment that includes nivolumab may lead to long-term survival.

Targeting Metabolism to Control Immune Responses in Cancer and Improve Checkpoint Blockade Immunotherapy.

Simple SummaryIn a tumor context, antitumor immune cells mediate an inflammatory response after activating a metabolic switch to kill cancer cells. However, tumors develop strategies to avoid destruction. Cancer cells are able to modify the metabolic environment of the tumor by sequestering nutrients (e.g., glucose, tryptophan, arginine) and by producing toxic waste compounds (e.g., adenosine, lactate, kynurenine). This tumor environment promotes exhaustion of antitumor immune cells while driving the expansion of Tregs and the expression of immune checkpoints. Establishment of such an immunosuppressive tumor environment decreases treatment response of cancer patients to immunotherapy. Interestingly, immunometabolism knowledge allows new therapeutic strategies to increase antitumor immune response by targeting the metabolism of both cancer and immune cells to improve immunotherapy.Over the past decade, advances in cancer immunotherapy through PD1–PDL1 and CTLA4 immune checkpoint blockade have revolutionized the management of cancer treatment. However, these treatments are inefficient for many cancers, and unfortunately, few patients respond to these treatments. Indeed, altered metabolic pathways in the tumor play a pivotal role in tumor growth and immune response. Thus, the immunosuppressive tumor microenvironment (TME) reprograms the behavior of immune cells by altering their cellular machinery and nutrient availability to limit antitumor functions. Today, thanks to a better understanding of cancer metabolism, immunometabolism and immune checkpoint evasion, the development of new therapeutic approaches targeting the energy metabolism of cancer or immune cells greatly improve the efficacy of immunotherapy in different cancer models. Herein, we highlight the changes in metabolic pathways that regulate the differentiation of pro- and antitumor immune cells and how TME-induced metabolic stress impedes their antitumor activity. Finally, we propose some drug strategies to target these pathways in the context of cancer immunotherapy.

Clinical significance of anticancer vaccines (literature review)

During the past few decades, the advances in cancer immunotherapy have revived interest in the potential use of vaccines for the malignant tumor treatment. Tumor-associated antigens, which are abnormally expressed by tumor cells, are of decisive importance in the development of anticancer vaccines. Through the stimulation of immunological memory, therapeutic anticancer vaccines can result in long-term remission or healing patients. Therapeutic anticancer vaccines due to the potential safety, specificity and duration of effect can become an alternative to or increase the effectiveness of existing immunotherapies. This article presents data on the tumor antigen structure, characteristics of anticancer vaccines and the results of studies on the clinical efficacy of anticancer vaccines.

MA09.06 Mature Tertiary Lymphoid Structures in Lung Adenocarcinoma Are Associated With Better Progression Free Survival

Prior presentations (2019): The presence of secondary follicles in early stage lung adenocarcinoma reflect disease burden Advances in cancer immunotherapy, such as immune checkpoint inhibitors, including those targeted against programmed cell death (PD-1) have refocused interest in the role of the immune response in effectively controlling lung adenocarcinoma. The presence of inducible lymphoid structures known as tertiary lymphoid structures in the tumor microenvironment has been shown to correlate with positive clinical outcome.

Deciphering Repertoire of B16 Melanoma Reactive TCRs by Immunization, In Vitro Restimulation and Sequencing of IFNγ-Secreting T Cells.

Recent advances in cancer immunotherapy have great promise for the treatment of solid tumors. One of the key limiting factors that hamper the decoding of physiological responses to these therapies is the inability to distinguish between specific and nonspecific responses. The identification of tumor-specific lymphocytes is also the most challenging step in cancer cell therapies such as adoptive cell transfer and T cell receptor (TCR) cloning. Here, we have elaborated a protocol for the identification of tumor-specific T lymphocytes and the deciphering of their repertoires. B16 melanoma engraftment following anti-PD1 checkpoint therapy provides better antitumor immunity compared to repetitive immunization with heat-shocked tumor cells. We have also revealed that the most error-prone part of dendritic cell (DC) generation, i.e., their maturation step, can be omitted if DCs are cultured at a sufficiently high density. Using this optimized protocol, we have achieved a robust IFNγ response to B16F0 antigens, but only within CD4+ T helper cells. A comparison of the repertoires of IFNγ-positive and -negative cells shows a prominent enrichment of certain clones with putative tumor specificity among the IFNγ+ fraction. In summary, our optimized protocol and the data provided here will aid in the acquisition of broad statistical data and the creation of a meaningful database of B16-specific TCRs.

Soluble Biomarkers with Prognostic and Predictive Value in Advanced Non-Small Cell Lung Cancer Treated with Immunotherapy.

Simple SummaryImmunotherapy, most notably immune checkpoint inhibitors (ICIs), has revolutionized the treatment of advanced non-small cell lung cancer (NSCLC). Although some patients respond well to ICIs, many patients do not benefit from ICIs, leading to disease progression and/or immune-related adverse events. Biological markers can help to improve patient selection. However, currently available markers such as PD-1 and its ligand (PD-L1) have important limitations. For this reason, new biomarkers obtained by non-invasive methods are urgently needed. In the present review, we describe recent advances in the development of novel soluble biological markers (e.g., circulating immune cells, TMB, circulating tumor cells, circulating tumor DNA, soluble factor PD-L1, tumor necrosis factor, etc.) for patients with NSCLC treated with immunotherapy.Numerous targeted therapies have been evaluated for the treatment of non-small cell lung cancer (NSCLC). To date, however, only a few agents have shown promising results. Recent advances in cancer immunotherapy, most notably immune checkpoint inhibitors (ICI), have transformed the treatment scenario for these patients. Although some patients respond well to ICIs, many patients do not benefit from ICIs, leading to disease progression and/or immune-related adverse events. New biomarkers capable of reliably predicting response to ICIs are urgently needed to improve patient selection. Currently available biomarkers—including programmed death protein 1 (PD-1) and its ligand (PD-L1), and tumor mutational burden (TMB)—have major limitations. At present, no well-validated, reliable biomarkers are available. Ideally, these biomarkers would be obtained through less invasive methods such as plasma determination or liquid biopsy. In the present review, we describe recent advances in the development of novel soluble biomarkers (e.g., circulating immune cells, TMB, circulating tumor cells, circulating tumor DNA, soluble factor PD-L1, tumor necrosis factor, etc.) for patients with NSCLC treated with ICIs. We also describe the potential use of these biomarkers as prognostic indicators of treatment response and toxicity.

Assessing and Management of Neurotoxicity After CAR-T Therapy in Diffuse Large B-Cell Lymphoma.

Chimeric antigen receptor T-cell (CAR-T) therapy represents the most important advances in cancer immunotherapy, especially in hematological malignancies such as B-cell lymphomas. CAR-T cell therapy has significant activity in poor risk B-cell lymphomas. CAR-T cell therapy is associated with potentially life-threatening toxicities such as cytokine release syndrome (CRS) and neurotoxicity (NT). While CRS pathophysiology and management are well established, the understanding and treatment of NT continues to develop. All current CAR-T products approved for DLBCL have been associated with NT with some differences in their severity. As cell therapies continue to advance and its access broadening, it will be imperative for clinicians to be aware of the signs and symptoms of NT, its stratification and basic management.

Abstract 2977: Organoid-T-cell co-cultures for preclinical testing of adoptive cell and cancer immunotherapy

Abstract Recent advances in cancer immunotherapy had a positive impact on the life expectancy of patients with a large range of clinical indications. With new treatment strategies and druggable targets being identified at an increasing pace, the number of patients eligible for cancer immunotherapy is expected to expand steadily. However, promising therapeutic developments face hurdles in translating preclinical findings into therapy. Challenges range from lack of confidence in animal cancer models, inter-tumor heterogeneity and the absence of cellular microenvironment. Hubrecht Organoid Technology (HUB) offers an innovative alternative, build on the discovery that adult stem cells proliferate and organize into three-dimensional organotypic structures when they are embedded into Matrigel. HUBOrganoids™ are generated from healthy and disease tissues and stored as “living” biobanks with high quality and reproducibility. HUB Organoids recapitulate complex characteristics of the original parental tissue, including molecular heterogeneity, and morphological and functional traits. HUB has developed organoid-T-cell co-culture systems that allow a physiologic representation of the complexity of interactions in the tumor microenvironment, which is important for evaluating the effects of novel therapies. HUB offers an innovative platform combining image-based analysis with flow cytometry to visualize and quantify T-cell-tumor interactions as well as measurements of T-cell cytotoxicity against tumor (and normal-matched) organoids for colorectal and several other cancers. Our platform offers a powerful strategy for the development and validation of cancer immunotherapy and may help to screen the efficacy of immune checkpoint blockade or bispecific antibodies. In addition, cancer organoid-T-cell co-culture may also predict the functionality of tumor-infiltrating lymphocytes (TIL) and chimeric antigen receptor (CAR)-engineered T cells. As such, our platform offers opportunities in preclinical development and could become a diagnostic tool to predict individual patient response to immunotherapy. Citation Format: Pleun Hombrink, Soura Mardpour, Ewout Spaan, Jarmil Hanrath, Farzin Pourfarzad, Jasper Mullenders, Rene Overmeer, G.J Robert, Vries, F Sylvia, Boj. Organoid-T-cell co-cultures for preclinical testing of adoptive cell and cancer immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2977.

The role of immunotherapy in eliminating high-risk treatments for pediatric cancer

Chemotherapy, radiation, and surgery are often ineffective in treating refractory or chronic tumors in children. Recent advances in cancer immunotherapy have also improved the outcome of many human tumors, resulting in significant responses in patients who have previously refused to respond to other treatments. The immune system is made up of cells and proteins that work together to maintain immunity against pathogens. Cancer cells can adapt and metastasize over time, express different neoantigens, or express more immune-suppressing mechanisms, allowing them to be identified and eradicated. In this study, we focus on immunotherapy for pediatric cancer and its progression using natural killer (NK) cells, chimeric antigen receptor T cells (CAR-T), and oncolytic virus cells in these patients. For all intents and purposes, toxicity is a concern. Although immunotherapy is believed to have fewer long-term side effects than chemotherapy and radiation therapy, they may have a high rate of short-term side effects, depending on the cause and purpose. These complications can lead to life-threatening illnesses, from mild illnesses such as fever and headaches to more severe illnesses such as autoimmune, neurotoxicity, and opportunistic infections. Any of the problems listed, for example, cytokine release syndrome, can be fatal. Different intensities require multiple tests and trials.

JAK/STAT-Dependent Chimeric Antigen Receptor (CAR) Expression: A Design Benefiting From a Dual AND/OR Gate Aiming to Increase Specificity, Reduce Tumor Escape and Affect Tumor Microenvironment.

Recent advances in cancer immunotherapy have attracted great interest due to the natural capacity of the immune system to fight cancer. This field has been revolutionized by the advent of chimeric antigen receptor (CAR) T cell therapy that is utilizing an antigen recognition domain to redirect patients’ T cells to selectively attack cancer cells. CAR T cells are designed with antigen-binding moieties fused to signaling and co-stimulatory intracellular domains. Despite significant success in hematologic malignancies, CAR T cells encounter many obstacles for treating solid tumors due to tumor heterogeneity, treatment-associated toxicities, and immunosuppressive tumor microenvironment. Although the current strategies for enhancing CAR T cell efficacy and specificity are promising, they have their own limitations, making it necessary to develop new genetic engineering strategies. In this article, we have proposed a novel logic gate for recognizing tumor-associated antigens by employing intracellular JAK/STAT signaling pathway to enhance CAR T Cells potency and specificity. Moreover, this new-generation CAR T cell is empowered to secrete bispecific T cell engagers (BiTEs) against cancer-associated fibroblasts (CAFs) to diminish tumor metastasis and angiogenesis and increase T cell infiltration.

Elucidation of the pathophysiology of cancer immunotherapy resistance focusing on tryptophan metabolism

Associate Professor Soranobu Ninomiya, Graduate School of Medicine, Gifu University, Japan, is investigating the potential for IDO, a tryptophan-metabolising enzyme that is highly expressed in tumours, to be used in cancer treatment. He is building on existing knowledge that intratumor IDO expression and serum kynurenine levels are useful as prognostic factors in cancer patients. The treatment that Ninomiya and the team are developing blocks the action of IDO in cancer cells, thereby enhancing the effect of cancer immunotherapy as IDO weakens the power of immunocytes. Advances in cancer immunotherapy and specifically immune checkpoint inhibitors have led to new cancer treatments, with their effectiveness confirmed by CART therapy. Using a mouse model, Ninomiya and the team elucidated the usefulness of CD19-CART therapy, which is a novel cancer immunotherapy for the treatment of diffuse large B-cell lymphoma (DLBCL), and IDO inhibitor combination therapy. The researchers also clarified that tryptophan deficiency in the serum can cause skeletal muscle atrophy, by using myoblasts and skeletal muscles of a mouse and, in addition, examined muscular atrophy using CT images of cancer patients. Ninomiya and the team are confident that IDO has great potential to be a candidate therapeutic target for patients with DLBCL, especially those who have been found to be resistant to chemotherapy.

PD-1 blockade prevents the progression of oral carcinogenesis.

Oral squamous cell carcinoma (OSCC) is one of the most common malignancies in the head and neck with a poor prognosis. Oral cancer development is a multistep process involving carcinogenesis. Though significant advances in cancer immunotherapy over the years, there is lack of evidence for T-cell exhaustion during oral carcinogenesis. Clinical specimens from healthy donors and patients diagnosed with oral leukoplakia (OLK) or OSCC were collected for immunohistochemical staining with PD-L1, CD86, CD8, PD-1 and CTLA-4 antibodies. Meanwhile, chemically induced mouse models of oral carcinogenesis were constructed with 4-nitroquinolone-N-oxide induction. Exhaustion status of T cells was measured by flow cytometry for spleens and by multiplex immunohistochemistry for formalin-fixed paraffin-embedded lesions in multiple stages of oral carcinogenesis. The efficacy of PD-1 blockade with or without cisplatin treatment was evaluated on the mice in precancerous and OSCC stages. We observed higher expression of PD-1 in the human OLK and OSCC tissues compared with the normal, while low expression CTLA-4 in all oral mucosa tissues. Animal experiments showed that the exhausted CD4+ T cells existed much earlier than exhausted CD8+ T cells, and an increased ratio of stem-like exhausted T cells and partially exhausted T cells were detected in the experimental groups. Besides, the expression of immune checkpoint markers (PDCD1, CTLA4 and HAVCR2) was strongly positively correlated with cytokines (IFNG and IL-2). In summary, T-cell exhaustion plays a vital role in oral carcinogenesis, and PD-1 blockade can prevent the progression of oral carcinogenesis.

High grade gliomas impact cell fate differentiation of hematopoietic stem and progenitor cells in the bone marrow

Abstract Glioblastoma (GBM) remains a deadly disease with an overall survival of 18 months. Despite advances in cancer immunotherapy, especially in the context of solid tumors derived outside of the central nervous system, GBM remains difficult to treat. This may be due, in part, to reduced T cell function and expansion of suppressive myeloid cells within the periphery. Here we sought to determine if GBM impacts the phenotype and gene expression of progenitor populations within the bone marrow where hematopoietic stem and progenitor cells (HSPCs) originate. Using RNAseq, we found HSPCs derived from intracranial glioma-bearing mice possess altered gene expression relative to HSPCs derived from non-tumor-bearing mice. In addition, we found glioma-bearing mice possess an expansion of myeloid-derived suppressor cells (MDSCs) within their bone marrow and are significantly more suppressive on T cell proliferation and T cell-mediated tumor cell killing than MDSCs isolated from non-tumor-bearing mice. We also determined HSPCs derived from glioma-bearing mice are more likely to differentiate into MDSCs than HSPCs derived from non-tumor-bearing mice. Interestingly, we found components of immunotherapy are capable of redirecting cell fate differentiation of glioma-bearing HSPCs. We determined HSPCs cultured in T cell supernatants are capable redirecting their differentiation from suppressive MDSCs towards stimulatory DCs. Finally, using two murine glioma models, we found adoptive cellular therapy using HSPCs derived from glioma-bearing mice is capable of providing a similar survival benefit as adoptive cellular therapy using HSPCs derived from non-tumor-bearing mice.

Immunocompetent cancer-on-chip models to assess immuno-oncology therapy

The advances in cancer immunotherapy come with several obstacles, limiting its widespread use and benefits so far only to a small subset of patients. One of the underlying challenges remains to be the lack of representative nonclinical models that translate to human immunity and are able to predict clinical efficacy and safety outcomes. In recent years, immunocompetent Cancer-on-Chip models emerge as an alternative human-based platform that enables the integration and manipulation of complex tumor microenvironment. In this review, we discuss novel opportunities offered by Cancer-on-Chip models to advance (mechanistic) immuno-oncology research, ranging from design flexibility to multimodal analysis approaches. We then exemplify their (potential) applications for the research and development of adoptive cell therapy, immune checkpoint therapy, cytokine therapy, oncolytic virus, and cancer vaccines.

PD-L1 as a Potential Target in Cancer Therapy (Review)

Introduction. Cancer is one of the most serious and common diseases with a high level of mortality. Due to this reason the searching of new directions and methods of cancer treatment is becoming more and more important with each passing year. Significant advances in cancer immunotherapy have been reached over the past few decades. Moreover, an inhibition of the interaction between the programmed cell death receptor (PD-1) and its ligand (PD-L1), is sure to be perspective direction of the immuno-oncological therapy development.Text. PD-1/PD-L1 interaction plays a pivotal role in negative regulation of immune system, that protects host’s cells and tissues from the excessive immune response. However, it is also used by tumor cells to avoid the host's immune system. The discovery of this mechanism led to the development of inhibiting PD-1 or PD-L1 agents that enhance anti-tumor immunity. Meanwhile, anti-PD-L1 agents provide less toxicity in comparison with anti-PD-1 agents. FDA currently approved Atesolizumab, Durvalumab, and Avelumab PD-L1 inhibitors for cancer treatment. These agents demonstrated effective response during the clinical trials, however, they are used for a limited number of oncological diseases. In addition, BMS-936559 is a promising agent that had passed the first stage of the clinical trials. Nevertheless, immunotherapy involving PD-L1 inhibitors is closely related to a vast number of severe side effects including immune-mediated effects caused by the inhibition of PD-L1 ligands located on healthy cells. In these terms, the development of new agents deprived of these disadvantages is the reason for further studies.Conclusion. Immunotherapy in cancer uncovers new perspectives in treatment of refractory to standard therapies forms of cancer. And the development of new and improvement of existing PD-L1 blocking agents are of great importance in fighting against tumoral diseases.