CTLA-4 gene variant -1661A>G may predict the onset of endocrine adverse events in metastatic melanoma patients treated with ipilimumab

Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio: Markers predicting immune-checkpoint inhibitor efficacy and immune-related adverse events

We conducted a comprehensive review of existing prediction models pertaining to the efficacy of immune-checkpoint inhibitor (ICI) and the occurrence of immune-related adverse events (irAEs). The predictive potential of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in determining ICI effectiveness has been extensively investigated, while limited research has been conducted on predicting irAEs. Furthermore, the combined model incorporating NLR and PLR, either with each other or in conjunction with additional markers such as carcinoembryonic antigen, exhibits superior predictive capabilities compared to individual markers alone. NLR and PLR are promising markers for clinical applications. Forthcoming models ought to incorporate established efficacious models and newly identified ones, thereby constituting a multifactor composite model. Furthermore, efforts should be made to explore effective clinical application approaches that enhance the predictive accuracy and efficiency.

Review - The impact of pharmacogenetics on the outcome of immune checkpoint inhibitors

The development of immune checkpoint inhibitors (ICIs) has a tremendous effect on the treatment options for multiple types of cancer. Nonetheless, there is a large interpatient variability in response, survival, and the development of immune-related adverse events (irAEs). Pharmacogenetics is the general term for germline genetic variations, which may cause the observed interindividual differences in response or toxicity to treatment. These genetic variations can either be single-nucleotide polymorphisms (SNPs) or structural variants, such as gene deletions, amplifications or rearrangements. For ICIs, pharmacogenetic variation in the human leukocyte antigen molecules has also been studied with regard to treatment outcome. This review presents a summary of the literature regarding the pharmacogenetics of ICI treatment, discusses the most important known genetic variations and offers recommendations on the application of pharmacogenetics for ICI treatment.

The predictive and prognostic role of single nucleotide gene variants of PD-1 and PD-L1 in patients with advanced melanoma treated with PD-1 inhibitors

Background

Despite having revolutionized the treatment paradigm for advanced melanoma, not all patients benefit from immune checkpoint inhibitor therapy. To date, there are no predictive biomarkers for response or the occurrence of immune-related adverse events (irAEs) to programmed cell death protein 1 (PD-1) inhibitors. Our aim was to investigate the predictive and prognostic role of single nucleotide variants (SNVs) of genes involved in the PD-1 axis.

Methods

We analysed, in metastatic melanoma patients treated with nivolumab or pembrolizumab, five PD-1 SNVs, namely PD1.3 G>A (rs11568821), PD1.5 C>T (rs2227981), PD1.6 G>A (rs10204525), PD1.7 T>C(rs7421861), PD1.10 C>G (rs5582977) and three programmed death-ligand 1 (PD-L1) SNVs: +8293 C>A (rs2890658), PD-L1 C>T (rs2297136) and PD-L1 G>C (rs4143815). Association of SNV genotypic frequencies with best overall response to PD-1 inhibitors and development of irAEs were estimated through a modified Poisson regression. A Cox regression modelling approach was applied to evaluate the SNV association with OS.

Results

A total of 125 patients with advanced melanoma were included in the analysis. A reduction in irAEs risk was observed in patients carrying the PD-L1 +8293 C/A genotype compared with those carrying the C/C genotype (risk ratio = 0.45; 95% CL 0.22-0.93; P = 0.031). A trend for a reduction in irAEs was also observed with the PD1.5 T allele (risk ratio = 0.70, 95% confidence limits 0.48-1.01 versus C allele). None of the SNVs was associated with response to therapy. Finally, a survival benefit was observed in patients harbouring the PD1.7 C/C genotype (hazard ratio = 0.37; 95% confidence limits 0.14-0.96; P = 0.028) in the homozygous model.

Conclusions

Our study showed that PD-1.5 and PD-L1 +8293 SNVs may play a role as a predictive biomarker of development of irAEs to PD-1 inhibitors. PD1.7 SNV may also be associated with a reduction of the risk of death, although further translational research is needed to confirm these results.

Unveiling the Etiopathogenic Spectrum of Hypophysitis: A Narrative Review

Hypophysitis, a rare inflammatory disorder of the pituitary gland, has seen an uptick in reported cases in recent years. Our objective is to summarize the most recent research on the etiopathogenesis, molecular mechanisms, and genetics of both primary and secondary hypophysitis. Primary autoimmune hypophysitis (PAH): During the acute phase of the disease, the pituitary gland in enlarged due to the infiltration of T and B lymphocytes. The chronic phase is characterized by progressive and irreversible pituitary atrophy. APA may play a role in the management, diagnosis, and prognosis of PAH. Specific autoantibodies such as anti-GH, anti-PIT-1, and anti-T-PIT have been found in patients with hypophysitis and hypopituitarism. A recent study suggested that a mechanism of escaping clonal deletion and mounting an immune response against self antigens can explain the unusual nature of the immune response observed in PAH patients. A cytokine array shows the presence of gamma-interferon and interleukin-17. Patients carrying mutations in the PIT1 or PROP1 genes may present PAH. Individuals carrying the HLA DQ8 haplotype are four times more likely to develop PAH. Immune checkpoint inhibitors induce hypophysitis (IIHs): IIHs is an increasingly frequent toxicity of in patients on treatment with inhibitors targeting cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death-1 (PD-1). ICIs inhibit the CTLA-4 pathway, leading to overactivation of T lymphocytes. The binding of PD-1/PD-L1 suppresses the activity of T cells, promotes the conversion of T-helpers into T-regulatory cells, and activates pro-survival signaling pathways in cancer cells. Cytokines play a crucial role in IIHs. B-cell infiltration has been observed in IIHs, suggesting that antibody-mediated pituitary injury may contribute. Genetic polymorphisms of CTLA-4 and PD-1 genes can increase the risk of IIHs. HLA alleles may also be involved in the onset of IIHs; this HLA association presents a possible alternative mechanistic hypothesis. IIHs may also be linked to a paraneoplastic syndrome triggered by ectopic expression of pituitary specific antigens. SARS-CoV-2-related hypophysitis: Recently, the literature has reported occurrences of hypophysitis associated with the SARS-CoV-2 virus; long COVID-19 may also present as infundibulo-neuro-hypophysitis. The virus enters the central nervous system because of its distinct interaction with angiotensin-converting enzyme receptors via spike proteins binding the capillary endothelium, and it directly damages the pituitary cells. The effect of SARS-CoV-2 can occur indirectly through inflammation and the release of cytokines. The exact mechanism remains ambiguous. The available data on endocrine complications associated with the SARS-CoV-2 vaccine are scant. Nonetheless, isolated cases of hypophysitis have been documented. Treatment of hypophysitis: Glucocorticoids are the cornerstone in managing primary hypophysitis, given their targeted action on inflammation. A better understanding of the etiopathogenesis and molecular mechanism of hypophysitis can lead to more effective and personalized treatment strategies.

Dose Optimization in Oncology Drug Development: The Emerging Role of Pharmacogenomics, Pharmacokinetics, and Pharmacodynamics

Drugs' safety and effectiveness are evaluated in randomized, dose-ranging trials in most therapeutic areas. However, this is only sometimes feasible in oncology, and dose-ranging studies are mainly limited to Phase 1 clinical trials. Moreover, although new treatment modalities (e.g., small molecule targeted therapies, biologics, and antibody-drug conjugates) present different characteristics compared to cytotoxic agents (e.g., target saturation limits, wider therapeutic index, fewer off-target side effects), in most cases, the design of Phase 1 studies and the dose selection is still based on the Maximum Tolerated Dose (MTD) approach used for the development of cytotoxic agents. Therefore, the dose was not optimized in some cases and was modified post-marketing (e.g., ceritinib, dasatinib, niraparib, ponatinib, cabazitaxel, and gemtuzumab-ozogamicin). The FDA recognized the drawbacks of this approach and, in 2021, launched Project Optimus, which provides the framework and guidance for dose optimization during the clinical development stages of anticancer agents. Since dose optimization is crucial in clinical development, especially of targeted therapies, it is necessary to identify the role of pharmacological tools such as pharmacogenomics, therapeutic drug monitoring, and pharmacodynamics, which could be integrated into all phases of drug development and support dose optimization, as well as the chances of positive clinical outcomes.

Predictive Biomarkers for Checkpoint Inhibitor Immune-Related Adverse Events

Immune-checkpoint inhibitors (ICIs) are antagonists of inhibitory receptors in the immune system, such as the cytotoxic T-lymphocyte-associated antigen-4, the programmed cell death protein-1 and its ligand PD-L1, and they are increasingly used in cancer treatment. By blocking certain suppressive pathways, ICIs promote T-cell activation and antitumor activity but may induce so-called immune-related adverse events (irAEs), which mimic traditional autoimmune disorders. With the approval of more ICIs, irAE prediction has become a key factor in improving patient survival and quality of life. Several biomarkers have been described as potential irAE predictors, some of them are already available for clinical use and others are under development; examples include circulating blood cell counts and ratios, T-cell expansion and diversification, cytokines, autoantibodies and autoantigens, serum and other biological fluid proteins, human leucocyte antigen genotypes, genetic variations and gene profiles, microRNAs, and the gastrointestinal microbiome. Nevertheless, it is difficult to generalize the application of irAE biomarkers based on the current evidence because most studies have been retrospective, time-limited and restricted to a specific type of cancer, irAE or ICI. Long-term prospective cohorts and real-life studies are needed to assess the predictive capacity of different potential irAE biomarkers, regardless of the ICI type, organ involved or cancer site.

Correlation of preclinical and clinical biomarkers with efficacy and toxicity of cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have revealed significant clinical values in different solid tumors and hematological malignancy, changing the landscape for the treatment of multiple types of cancer. However, only a subpopulation of patients has obvious tumor response and long-term survival after ICIs treatment, and many patients may experience other undesirable clinical features. Therefore, biomarkers are critical for patients to choose exact optimum therapy. Here, we reviewed existing preclinical and clinical biomarkers of immunotherapeutic efficacy and immune-related adverse events (irAEs). Based on efficacy prediction, pseudoprogression, hyperprogressive disease, or irAEs, these biomarkers were divided into cancer cell-derived biomarkers, tumor microenvironment-derived biomarkers, host-derived biomarkers, peripheral blood biomarkers, and multi-modal model and artificial intelligence assessment-based biomarkers. Furthermore, we describe the relation between ICIs efficacy and irAEs. This review provides the overall perspective of biomarkers of immunotherapeutic outcome and irAEs prediction during ICIs treatment.

Current landscape and tailored management of immune-related adverse events

Unprecedented advances have been made in immune checkpoint inhibitors (ICIs) in the treatment of cancer. However, the overall benefits from ICIs are impaired by the increasing incidence of immune-related adverse events (irAEs). Although several factors and mechanisms have been proposed in the development of irAEs, there is still incomprehensive understanding of irAEs. Therefore, it is urgent to identify certain risk factors and biomarkers that predict the development of irAEs, as well as to understand the underlying mechanisms of these adverse events. Herein, we comprehensively summarize the state-of-the-art knowledge about clinical features and the related risk factors of irAEs. Particularly, we also discuss relevant mechanisms of irAEs and address the mechanism-based strategies, aiming to develop a tailored management approach for irAEs.

Germline genetic variation and predicting immune checkpoint inhibitor induced toxicity

Immune checkpoint inhibitor (ICI) therapy has revolutionised the treatment of various cancer types. ICIs reinstate T-cell function to elicit an anti-cancer immune response. The resulting immune response can however have off-target effects which manifest as autoimmune type serious immune-related adverse events (irAE) in ~10-55% of patients treated. It is currently challenging to predict both who will experience irAEs and to what severity. Identification of patients at high risk of serious irAE would revolutionise patient care. While the pathogenesis driving irAE development is still unclear, host genetic factors are proposed to be key determinants of these events. This review presents current evidence supporting the role of the host genome in determining risk of irAE. We summarise the spectrum and timing of irAEs following treatment with ICIs and describe currently reported germline genetic variation associated with expression of immuno-modulatory factors within the cancer immunity cycle, development of autoimmune disease and irAE occurrence. We propose that germline genetic determinants of host immune function and autoimmune diseases could also explain risk of irAE development. We also endorse genome-wide association studies of patients being treated with ICIs to identify genetic variants that can be used in polygenic risk scores to predict risk of irAE.

The changing clinical spectrum of endocrine adverse events in cancer immunotherapy

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of several malignancies, improving patient survival and quality of life. Endocrinopathies have emerged as a clinically significant group of immune-related adverse events (IRAEs). Although the mechanism of ICI toxicities has not been clarified, inhibition of immune checkpoints reduces immune tolerance to autoantigens, resulting in the development of autoimmunity disorders. We report current evidence regarding endocrine IRAEs that may have diagnostic and therapeutic implications. Management should be focused on a multidisciplinary approach to reach a prompt diagnosis and an appropriate and safe treatment.

Facts and Hopes in Prediction, Diagnosis, and Treatment of Immune-Related Adverse Events

Over the past decade, the use of immune checkpoint inhibitors (ICI) has expanded across a wide spectrum of oncology indications. Immune-related adverse events (irAE) from ICIs represent a significant source of morbidity, and in rare instances, can lead to treatment-related mortality. There are significant opportunities to better identify patients at increased risk for immune-related toxicity, diagnose irAEs more accurately and earlier in their course, and develop more individualized therapeutic strategies once complications arise. Clinical characteristics, germline and somatic genetic features, microbiome composition, and circulating biomarkers have all been associated with higher risk of developing irAEs in retrospective series. Many of these data suggest that both antitumor and anti-host ICI-associated immune reactions may be driven by common features of either the tumor or the patient's preexisting immune milieu. While irAE diagnosis is currently based on clinical history, exclusion of alternative etiologies, and sometimes pathologic confirmation, novel blood-based and radiographic assays are in development to identify these complications more precisely. Anecdotal reports and small case series have highlighted the potential role of targeted immunomodulatory agents to treat irAEs, though further prospective investigation is needed to evaluate more rigorously their use in these settings. In this review, we highlight the current state of knowledge about predicting, diagnosing, and treating irAEs with a translational focus and discuss emerging strategies which aim to improve each of these domains.

Molecular and Genetic Immune Biomarkers of Primary and Immune-Therapy Induced Hypophysitis: From Laboratories to the Clinical Practice

Hypophysitis is a rare and potentially life-threatening disease, characterized by an elevated risk of complications, such as the occurrence of acute central hypoadrenalism, persistent hypopituitarism, or the extension of the inflammatory process to the neighboring neurological structures. In recent years, a large number of cases has been described. The diagnosis of hypophysitis is complex because it is based on clinical and radiological criteria. Due to this, the integration of molecular and genetic biomarkers can help physicians in the diagnosis of hypophysitis and play a role in predicting disease outcome. In this paper, we review current knowledge about molecular and genetic biomarkers of hypophysitis with the aim of suggesting a possible integration of these biomarkers in clinical practice.

Genetic determinants of immune-related adverse events in patients with melanoma receiving immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) can cause profound immune-related adverse events (irAEs). The host genetic background is likely to play a role in irAE susceptibility because the presentation of toxicity varies among patients and many do not develop irAEs despite continued ICI use. We sought to identify potential genetic markers conferring risk for irAEs.

METHODS

We conducted a pilot exploratory study in 89 melanoma patients who received ICIs (44 with irAEs, and 45 without irAEs after at least 1 year from starting treatment). Genotyping was performed using the Infinium Multi-Ethnic Global-8 v1.0 Bead Chip. The genotype data were extracted using PLINK (v1.90b3.34) and processed for quality control. Population structure-based clustering was carried out using IBS matrix, pairwise population concordance test (p < 1 × 10-3), and phenotype distribution for all study participants, resulting in seven population structure-based clusters. In the analytical stage, 599,931 variants in autosomal chromosomes were included for the association study. The association test was performed using an additive genetic model with exact logistic regression, adjusted for age, sex, and population cluster.

RESULTS

A total of 30 variants or single-nucleotide polymorphisms with p < 1 × 10-4 were identified; 12 were associated with an increased risk of irAEs, and the remaining 18 were associated with a decreased risk. Overall, nine of the identified single-nucleotide polymorphisms mapped to eight unique genes that have been associated with autoimmunity or inflammatory diseases.

CONCLUSION

Several genetic variants associated with irAEs were identified. Additional larger studies are needed to validate these findings and establish their potential functional relevance.

Impact of genetic factors on platinum-induced gastrointestinal toxicity

Severe gastrointestinal (GI) toxicity is a common side effect after platinum-based chemotherapy. The incidence and severity of GI toxicity vary among patients with the same chemotherapy. Genetic factors involved in platinum transport, metabolism, detoxification, DNA repair, cell cycle control, and apoptosis pathways may account for the interindividual difference in GI toxicity. The influence of gene polymorphisms in the platinum pathway on GI toxicity has been extensively analyzed. Variations in study sample size, ethnicity, design, treatment schedule, dosing, endpoint definition, and assessment of toxicity make it difficult to precisely interpret the results. Hence, we conducted a review to summarize the most recent pharmacogenomics studies of GI toxicity in platinum-based chemotherapy and identify the most promising avenues for further research.

The Road so Far in Colorectal Cancer Pharmacogenomics: Are We Closer to Individualised Treatment?

In recent decades, survival rates in colorectal cancer have improved greatly due to pharmacological treatment. However, many patients end up developing adverse drug reactions that can be severe or even life threatening, and that affect their quality of life. These remain a limitation, as they may force dose reduction or treatment discontinuation, diminishing treatment efficacy. From candidate gene approaches to genome-wide analysis, pharmacogenomic knowledge has advanced greatly, yet there is still huge and unexploited potential in the use of novel technologies such as next-generation sequencing strategies. This review summarises the road of colorectal cancer pharmacogenomics so far, presents considerations and directions to be taken for further works and discusses the path towards implementation into clinical practice.

Phenotypic characterization of tumor CTLA-4 expression in melanoma tissues and its possible role in clinical response to Ipilimumab

The expression of the immune checkpoint molecule CTLA-4 has been almost exclusively studied in the T cell lineage, but increasing evidence has shown its expression on tumors with implications for immunotherapy. To date, the degree of expression of CTLA-4 on tumor cells as a predictive biomarker of response to immune checkpoint inhibitors has not been studied. In this report, we analyzed this issue in melanoma patients treated with CTLA-4 inhibitor Ipilimumab (IPI). We show that the level of CTLA-4 expression on melanoma cells is higher than that on tumor infiltrating lymphocytes (TIL) and it is associated with clinical response to IPI therapy supporting the idea of its possible role as a predictive biomarker.

Immune-Related Adverse Events: A Case-Based Approach

Immunotherapy has heralded the advent of a new era in oncology. Immune checkpoint inhibitors (ICIs) enhance anti-tumor immunity, thereby reinvigorating a patient's immune system to fight cancer. While therapy with this class of agents has resulted in improved clinical outcomes for patients with multiple tumor types, a broad spectrum of immune-related adverse events (irAEs) may affect any organ system, with variable clinical presentations. Prompt recognition and management of irAEs are associated with improved irAE outcomes, and represents an important new clinical challenge for practicing oncologists. Herein, we provide a comprehensive case-based review of the most common and clinically-important irAEs, focussing on epidemiology, clinical manifestations, and management. We also examine future strategies that may provide meaningful insights into the prevention and management of irAEs.

Pharmacogenetics of anticancer monoclonal antibodies

Pharmacogenetics is the study of therapeutic and adverse responses to drugs based on an individual’s genetic background. Monoclonal antibodies (mAbs) are a rapidly evolving field in cancer therapy, however a number of newly developed and highly effective mAbs (e.g., anti-CTLA-4 and anti-PD-1) possess pharmacogenomic profiles that remain largely undefined. Since the first chemotherapeutic mAb Rituximab was approved in 1997 by the US Food and Drug Administration for cancer treatment, a broad number of other mAbs have been successfully developed and implemented into oncological practice. Nowadays, mAbs are considered as one of the most promising new approaches for cancer treatment. The efficacy of mAb treatment can however be significantly affected by genetic background, where genes responsible for antibody presentation and metabolism, for example, can seriously affect patient outcome. This review will focus on current anticancer mAb treatments, patient genetics that shape their efficacy, and the molecular pathways that bridge the two.

Association of HLA-DRB1 shared epitope alleles and immune checkpoint inhibitor-induced inflammatory arthritis

OBJECTIVE

To evaluate the frequency of HLA class I and II alleles associated with traditional forms of inflammatory arthritis in patients with immune checkpoint inhibitor (ICI)-induced inflammatory arthritis as compared with population controls.

METHODS

High-resolution HLA typing was performed on 27 patients with ICI-induced inflammatory arthritis and 726 healthy controls. Genotyping at the shared epitope (SE) locus (HLA DRB1) was performed on 220 RA cases. Allele-positivity rates and frequency of having at least one SE allele were compared using Fisher's exact test between ICI-induced inflammatory arthritis and healthy controls. Frequency of having at least one SE allele was also compared between ICI-induced inflammatory arthritis and RA cases.

RESULTS

Twenty-six patients with ICI-induced inflammatory arthritis were of European descent, and one was African American. In those 26 patients, 16 (61.5%) had at least one SE allele, significantly different from healthy controls of European descent, in whom 299 (41.2%) had at least one SE allele (odds ratio 2.3, P = 0.04). The allele-positivity rate of DRB1*04: 05 was also higher in the ICI-induced inflammatory arthritis group. The ICI-induced inflammatory arthritis population and RA patients of European descent did not differ in frequency of having at least one SE allele, but ICI-induced inflammatory arthritis patients were more likely to be autoantibody-negative for RF and anti-CCP antibodies.

CONCLUSION

Patients with ICI-induced inflammatory arthritis of European descent were more likely to have at least one SE allele than healthy controls. Further studies are needed to validate these findings and investigate whether a unique immunogenetic framework increases risk for different immune-related adverse events.

Soluble CTLA-4 as a favorable predictive biomarker in metastatic melanoma patients treated with ipilimumab: an Italian melanoma intergroup study

CTLA-4 blockade by means of ipilimumab (IPI) potentiates the immune response and improves overall survival (OS) in a minority of metastatic melanoma (MM) patients. We investigated the role of soluble CTLA-4 (sCTLA-4) as a possible biomarker for identifying this subset of patients. sCTLA-4 levels were analyzed at baseline in sera from 113 IPI-treated MM patients by ELISA, and the median value (200 pg/ml) was used to create two equally sized subgroups. Associations of sCTLA-4 with best overall response (BOR) to IPI and immune-related adverse events (irAEs) were evaluated through logistic regression. Kaplan-Meier and Cox regression methods were used to analyze OS. A remarkable association between sCTLA-4 levels and BOR was found. Specifically, the proportion of patients with sCTLA-4 > 200 pg/ml in irSD or irPD (immune-related stable or progressive disease) was, respectively, 80% (OR = 0.23; 95%CL = 0.03-1.88) and 89% (OR = 0.11; 95%CL = 0.02-0.71) and was lower than that observed among patients in irCR/irPR (immune-related complete/partial response). sCTLA-4 levels increased during IPI treatment, since the proportion of patients showing sCTLA > 200 pg/ml after 3 cycles was 4 times higher (OR = 4.41, 95%CL = 1.02-19.1) than that after 1 cycle. Moreover, a significantly lower death rate was estimated for patients with sCTLA-4 > 200 pg/ml (HR = 0.61, 95%CL = 0.39-0.98). Higher baseline sCTLA-4 levels were also associated with the onset of any irAE (p value = 0.029), in particular irAEs of the digestive tract (p value = 0.041). In conclusion, our results suggest that high sCTLA-4 serum levels might predict favorable clinical outcome and higher risk of irAEs in IPI-treated MM patients.

Immune Checkpoints and Innovative Therapies in Glioblastoma

Targeting the Immune Checkpoint molecules (ICs; CTLA-4, PD-1, PD-L1/2, and others) which provide inhibitory signals to T cells, dramatically improves survival in hard-to-treat tumors. The establishment of an immunosuppressive environment prevents endogenous immune response in glioblastoma; therefore, manipulating the host immune system seems a reasonable strategy also for this tumor. In glioma patients the accumulation of CD4+/CD8+ T cells and Treg expressing high levels of CTLA-4 and PD-1, or the high expression of PD-L1 in glioma cells correlates with WHO high grade and short survival. Few clinical studies with IC inhibitors (ICis) were completed so far. Notably, the first large-scale randomized trial (NCT 02017717) that compared PD-1 blockade and anti-VEGF, did not show an OS increase in the patients treated with anti-PD-1. Several factors could have contributed to the failure of this trial and must be considered to design further clinical studies. In particular the possibility of targeting at the same time different ICs was pre-clinically tested in an animal model were inhibitors against IDO, CTLA-4 and PD-L1 were combined and showed persistent and significant antitumor effects in glioma-bearing mice. It is reasonable to hypothesize that the immunological characterization of the tumor in terms of type and level of expressed IC molecules on the tumor and TIL may be useful to design the optimal ICi combination for a given subset of tumor to overcome the immunosuppressive milieu of glioblastoma and to efficiently target a tumor with such high cellular complexity.