Prophylactic IL-23 blockade uncouples efficacy and toxicity in dual CTLA-4 and PD-1 immunotherapy.

BACKGROUND: Immune-related adverse events (irAEs), characterized by targeted inflammation, occur in up to 60% of patients with melanoma treated with immune checkpoint inhibitors (ICIs). Evidence proved that the baseline peripheral blood profiles of patients at risk for severe irAEs development paralleled clinical autoimmunity. Interleukin (IL)-23 blockade with risankizumab is recommended for cases that are suffering from autoimmune disease, such as autoimmune colitis. However, currently, the role of IL-23 in irAEs onset and severity remains poorly understood. METHODS: The pro-inflammatory cytokines most associated with severe irAEs onset were identified by retrospective analysis based on GSE186143 data set. To investigate the efficacy of prophylactic IL-23 blockade administration to prevent irAEs, refer to a previous study, we constructed two irAEs murine models, including dextran sulfate sodium salt (DSS)-induced colitis murine model and a combined-ICIs-induced irAEs murine model. To further explore the applicability of our findings, murine models with graft-versus-host disease were established, in which Rag2-/-Il2rg-/- mice were transferred with human peripheral blood mononuclear cells and received combined cytotoxic T-lymphocyte associated antigen 4 (CTLA-4) and programmed cell death protein-1 (PD-1) treatment. Human melanoma cells were xenografted into these mice concomitantly. RESULTS: Here we show that IL-23 was upregulated in the serum of patients suffering from irAEs after dual anti-CTLA-4 and anti-PD-1 treatment, and increased as a function of irAEs severity. Additionally, Augmented CD4+ Tems may preferentially underlie irAEs onset. Treating mice with anti-mouse IL-23 antibody concomitantly with combined CTLA-4 and PD-1 immunotherapy ameliorates colitis and, in addition, preserves antitumor efficacy. Moreover, in xenografted murine models with irAEs, prophylactic blockade of human IL-23 using clinically available IL-23 inhibitor (risankizumab) ameliorated colitis, hepatitis and lung inflammation, and moreover, immunotherapeutic control of tumors was retained. Finally, we also provided a novel machine learning-based computational framework based on two blood-based features-IL-23 and CD4+ Tems-that may have predictive potential for severe irAEs and ICIs response. CONCLUSIONS: Our study not only provides clinically feasible strategies to dissociate efficacy and toxicity in the use of combined ICIs for cancer immunotherapy, but also develops a blood-based biomarker that makes it possible to achieve a straightforward and non-invasive, detection assay for early prediction of irAEs onset.

Phase I studies of davoceticept (ALPN-202), a PD-L1-dependent CD28 co-stimulator and dual PD-L1/CTLA-4 inhibitor, as monotherapy and in combination with pembrolizumab in advanced solid tumors (NEON-1 and NEON-2).

BACKGROUND: Davoceticept (ALPN-202) is an Fc fusion of a CD80 variant immunoglobulin domain designed to mediate programmed death-ligand 1 (PD-L1)-dependent CD28 co-stimulation while inhibiting the PD-L1 and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) checkpoints. The safety and efficacy of davoceticept monotherapy and davoceticept and pembrolizumab combination therapy in adult patients with advanced solid tumors were explored in NEON-1 and NEON-2, respectively. METHODS: In NEON-1 (n=58), davoceticept 0.001-10 mg/kg was administered intravenous either once weekly (Q1W) or once every 3 weeks (Q3W). In NEON-2 (n=29), davoceticept was administered intravenously at 2 dose levels (0.1 or 0.3 mg/kg) Q1W or Q3W with pembrolizumab (400 mg once every 6 weeks). In both studies, primary endpoints included incidence of dose-limiting toxicities (DLT); type, incidence, and severity of adverse events (AEs) and laboratory abnormalities; and seriousness of AEs. Secondary endpoints included antitumor efficacy assessed using RECIST v1.1, pharmacokinetics, anti-drug antibodies, and pharmacodynamic biomarkers. RESULTS: The incidence of treatment-related AEs (TRAEs) and immune-related adverse events (irAEs) was 67% (39/58) and 36% (21/58) with davoceticept monotherapy, and 62% (18/29) and 31% (9/29) with davoceticept and pembrolizumab combination, respectively. The incidence of ≥grade (Gr)3 TRAEs and ≥Gr3 irAEs was 12% (7/58) and 5% (3/58) with davoceticept monotherapy, and 24% (7/29) and 10% (3/29) with davoceticept and pembrolizumab combination, respectively. One DLT of Gr3 immune-related gastritis occurred during davoceticept monotherapy 3 mg/kg Q3W. During davoceticept combination with pembrolizumab, two Gr5 cardiac DLTs occurred; one instance each of cardiogenic shock (0.3 mg/kg Q3W, choroidal melanoma metastatic to the liver) and immune-mediated myocarditis (0.1 mg/kg Q3W, microsatellite stable metastatic colorectal adenocarcinoma), prompting early termination of both studies. Across both studies, five patients with renal cell carcinoma (RCC) exhibited evidence of clinical benefit (two partial response, three stable disease). CONCLUSIONS: Davoceticept was generally well tolerated as monotherapy at intravenous doses up to 10 mg/kg. Evidence of clinical activity was observed with davoceticept monotherapy and davoceticept in combination with pembrolizumab, notably in RCC. However, two fatal cardiac events occurred with the combination of low-dose davoceticept and pembrolizumab. Future clinical investigation with davoceticept should not consider combination with programmed death-1-inhibitor anticancer mechanisms, until its safety profile is more fully elucidated. TRIAL REGISTRATION NUMBER: NEON-1 (NCT04186637) and NEON-2 (NCT04920383).

Pre-existing autoimmune disease as a risk factor for immune-related adverse events in cancer patients receiving immune checkpoint inhibitors.

Immune checkpoint inhibitors (ICIs) have been widely used as standard therapies for various cancers. However, in 20-30% of cases, ICIs can lead to immune-related adverse events (irAEs), which sometimes require discontinuation of treatment. Due to the increased risk of irAEs, patients with pre-existing autoimmune diseases (AI) are often advised against receiving ICIs. However, there has not been sufficient objective risk assessment for AI. In our study, we conducted logistic regression analysis to assess the risk of irAEs by analyzing 478 cases that received anti-PD-(L)1 Ab and/or anti-CTLA4 Ab at our hospital between April 3, 2017, and May 24, 2022. Among these cases, 28 (5.9%) had pre-existing AI. We selected several independent factors for analysis: gender, age, performance status (PS), cancer type, type of ICI, type of combined anti-cancer agents, best overall response, and pre-existing AI. The adjusted odds ratio (OR) of AI for irAE occurrence was 2.52 [95% CI: 1.08-5.86] (p = 0.033), and the adjusted OR of AI for ICI discontinuation due to irAE was 3.32 [1.41-7.78] (p = 0.006). Patients with pre-existing AI experienced a significantly shorter irAE-free survival time compared to those without AI (median irAE-free survival: 5.7 months [95% CI: 3.5-7.8] vs 10.4 months [95% CI: 7.9-12.9], respectively, p = 0.035). Frequently observed irAEs in full ICI cohort, such as dermatologic issues (7.5%), pneumonitis (7.1%), hepatitis (4.6%), and hypothyroidism (4.2%), were often accompanied by pre-existing AI. Furthermore, pre-existing AI flared up in 6 cases (37.5% in AI-positive irAE-positive cases). The activity of AI was not related to the occurrence of irAEs. Grade 3 or higher irAEs were observed in 6 out of 20 (30.0%) cases in AI-accompanied patients complicated with irAEs. Although having a complicated AI increases the risk of irAEs, it may not necessarily be a contraindication for ICI treatment if closely monitored. (292<300 characters).

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

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Targeting cytotoxic lymphocyte antigen 4 (CTLA-4) in breast cancer.

Breast cancer (BC) has a high mortality rate and is one of the most common malignancies in the world. Initially, BC was considered non-immunogenic, but a paradigm shift occurred with the discovery of tumor-infiltrating lymphocytes (TILs) and regulatory T cells (Tregs) in the BC tumor microenvironment. CTLA-4 (Cytotoxic T-lymphocyte-associated protein 4) immunotherapy has emerged as a treatment option for BC, but it has limitations, including suboptimal antitumor effects and toxicity. Research has demonstrated that anti-CTLA-4 combination therapies, such as Treg depletion, cancer vaccines, and modulation of the gut microbiome, are significantly more effective than CTLA-4 monoclonal antibody (mAB) monotherapy. Second-generation CTLA-4 antibodies are currently being developed to mitigate immune-related adverse events (irAEs) and augment antitumor efficacy. This review examines anti-CTLA-4 mAB in BC, both as monotherapy and in combination with other treatments, and sheds light on ongoing clinical trials, novel CTLA-4 therapeutic strategies, and potential utility of biomarkers in BC.

Multiorgan Toxicity from Dual Checkpoint Inhibitor Therapy, Resulting in a Complete Response-A Case Report.

Immunotherapy treatment with checkpoint inhibitors (ICIs) has led to a breakthrough in the treatment of oncological diseases. Despite its clinical effectiveness, this treatment differs from others, such as cytotoxic chemotherapy, in that it causes immune-related adverse events. This type of toxicity can affect any organ or organ system of the body. We present a literature review and a rare clinical case from our clinical practice, in which a patient with metastatic clear cell renal carcinoma was treated with a single dose of dual checkpoint blockade (cytotoxic T-lymphocyte-4 (CTLA-4) and programmed death-1 (PD-1)) and simultaneously diagnosed with colitis, hepatitis, and nephritis. After early immunosuppressive treatment with the glucocorticoids, complete organ function recovery was achieved. The follow-up revealed a sustained complete response lasting more than a year.

Immune-checkpoint inhibitor-mediated myocarditis: CTLA4, PD1 and LAG3 in the heart.

Immune-checkpoint inhibitors (ICIs) have revolutionized oncology, with nearly 50% of all patients with cancer eligible for treatment with ICIs. However, patients on ICI therapy are at risk for immune-related toxicities that can affect any organ. Inflammation of the heart muscle, known as myocarditis, resulting from ICI targeting cytotoxic T lymphocyte-associated antigen 4 (CTLA4), programmed cell death protein 1 (PD1) and PD1 ligand 1 (PDL1) is an infrequent but potentially fatal complication. ICI-mediated myocarditis (ICI-myocarditis) is a growing clinical entity given the widespread use of ICIs, its increased clinical recognition and growing use of combination ICI treatment, a well-documented risk factor for ICI-myocarditis. In this Review, we approach ICI-myocarditis from a basic and mechanistic perspective, synthesizing the recent data from both preclinical models and patient samples. We posit that mechanistic understanding of the fundamental biology of immune-checkpoint molecules may yield new insights into disease processes, which will enable improvement in diagnostic and therapeutic approaches. The syndrome of ICI-myocarditis is novel, and our understanding of immune checkpoints in the heart is in its nascency. Yet, investigations into the pathophysiology will inform better patient risk stratification, improved diagnostics and precision-based therapies for patients.

CTLA-4 silencing could promote anti-tumor effects in hepatocellular.

Preclinical and clinical research showed that immune checkpoint blockade provides beneficial effects for many patients with liver cancer. This study aimed to assess the effect of CTLA-4-specific siRNA on the proliferation, cell cycle, migration, and apoptosis of HePG2 cells. Transfection of siRNA was performed by electroporation. The viability of cells was determined through MTT assay. Flow cytometry was performed to investigate the cell cycle and apoptosis rate, and the wound-healing assay was used to determine HepG2 cells migration. The expression levels of CTLA-4, c-Myc, Ki-67, BCL-2, BAX, caspase-9 (CAS9), and MMP-2,9,13 were measured by qRT-PCR. Transfection of specific CTLA-4-siRNA significantly inhibited the expression of the CTLA-4 gene. Also, our results revealed that CTLA-4 silencing diminished the proliferation and migration as well as induced the apoptosis of HePG2 cells. CTLA-4-siRNA transfection induced the cell cycle arrest in G2 phase. Moreover, CTLA-4-siRNA transfection reduced the expression levels of c-Myc, Ki-67, BCL-2, MMP-2,9,13, and elevated the expression levels of BAX and caspase-9. Our results suggest that silencing CTLA-4 through specific siRNA may be a promising strategy for future therapeutic interventions for treating liver cancer.

Dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 in lung cancer.

Cancer immunotherapies, represented by immune checkpoint inhibitors (ICIs), have reshaped the treatment paradigm for both advanced non-small cell lung cancer and small cell lung cancer. Programmed death receptor-1/programmed death receptor ligand-1 (PD-1/PD-L1) and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are some of the most common and promising targets in ICIs. Compared to ICI monotherapy, which occasionally demonstrates treatment resistance and limited efficacy, the dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 operates at different stages of T cell activation with synergistically enhancing immune responses against cancer cells. This emerging dual therapy heralds a new direction for cancer immunotherapy, which, however, may increase the risk of drug-related adverse reactions while improving efficacy. Previous clinical trials have explored combination therapy strategy of anti-PD-1/PD-L1 and anti-CTLA-4 agents in lung cancer, yet its efficacy remains to be unclear with the inevitable incidence of immune-related adverse events. The recent advent of bispecific antibodies has made this sort of dual targeting more feasible, aiming to alleviate toxicity without compromising efficacy. Thus, this review highlights the role of dual blockade immunotherapy targeting PD-1/PD-L1 and CTLA-4 in treating lung cancer, and further elucidates its pre-clinical mechanisms and current advancements in clinical trials. Besides, we also provide novel insights into the potential combinations of dual blockade therapies with other strategies to optimize the future treatment mode for lung cancer.

TG6050, an oncolytic vaccinia virus encoding interleukin-12 and anti-CTLA-4 antibody, favors tumor regression via profound immune remodeling of the tumor microenvironment.

BACKGROUND: TG6050 was designed as an improved oncolytic vector, combining the intrinsic properties of vaccinia virus to selectively replicate in tumors with the tumor-restricted expression of recombinant immune effectors to modify the tumor immune phenotype. These properties might be of particular interest for "cold" tumors, either poorly infiltrated or infiltrated with anergic T cells. METHODS: TG6050, an oncolytic vaccinia virus encodes single-chain human interleukin-12 (hIL-12) and full-length anti-cytotoxic T-lymphocyte-associated antigen-4 (@CTLA-4) monoclonal antibody. The relevant properties of TG6050 (replication, cytopathy, transgenes expression and functionality) were extensively characterized in vitro. The biodistribution and pharmacokinetics of the viral vector, @CTLA-4 and IL-12, as well as antitumoral activities (alone or combined with immune checkpoint inhibitors) were investigated in several "hot" (highly infiltrated) and "cold" (poorly infiltrated) syngeneic murine tumor models. The mechanism of action was deciphered by monitoring both systemic and intratumoral immune responses, and by tumor transcriptome analysis. The safety of TG6050 after repeated intravenous administrations was evaluated in cynomolgus monkeys, with a focus on the level of circulating IL-12. RESULTS: Multiplication and propagation of TG6050 in tumor cells in vitro and in vivo were associated with local expression of functional IL-12 and @CTLA-4. This dual mechanism translated into a strong antitumoral activity in both "cold" and "hot" tumor models (B16F10, LLC1 or EMT6, CT26, respectively) that was further amplified when combined with anti-programmed cell death protein-1. Analysis of changes in the tumor microenvironment (TME) after treatment with TG6050 showed increases in interferon-gamma, of CD8+T cells, and of M1/M2 macrophages ratio, as well as a drastic decrease of regulatory T cells. These local modifications were observed alongside bolstering a systemic and specific antitumor adaptive immune response. In toxicology studies, TG6050 did not display any observable adverse effects in cynomolgus monkeys. CONCLUSIONS: TG6050 effectively delivers functional IL-12 and @CTLA-4 into the tumor, resulting in strong antitumor activity. The shift towards an inflamed TME correlated with a boost in systemic antitumor T cells. The solid preclinical data and favorable benefit/risk ratio paved the way for the clinical evaluation of TG6050 in metastatic non-small cell lung cancer (NCT05788926 trial in progress).

Phase II basket trial of Dual Anti-CTLA-4 and Anti-PD-1 blockade in Rare Tumors (DART) SWOG S1609: adrenocortical carcinoma cohort.

OBJECTIVES: Multiple common cancers benefit from immunotherapy; however, less is known about efficacy in rare tumors. We report the results of the adrenocortical carcinoma cohort of NCI/SWOG S1609 Dual Anti-CTLA-4 and Anti-PD-1 blockade in Rare Tumors. DESIGN/SETTING: A prospective, phase 2 clinical trial of ipilimumab plus nivolumab was conducted by the SWOG Early Therapeutics and Rare Cancers Committee for multiple rare tumor cohorts across >1,000 National Clinical Trial Network sites. PARTICIPANTS: 21 eligible patients were registered. Median age was 53 years (range 26-69); 16 (76%) were women. INTERVENTIONS: Ipilimumab 1 mg/kg intravenously every 6 weeks with nivolumab 240 mg intravenously every 2 weeks was administered until disease progression, symptomatic deterioration, treatment delay for any reason >56 days, unacceptable or immune-related toxicity with inability to decrease prednisone to <10 mg daily, or per patient request. MAIN OUTCOME MEASURES: The primary endpoint was the overall response rate (ORR) (RECIST V.1.1). Secondary endpoints include clinical benefit rate (CBR) (includes stable disease (SD)>6 months), progression-free survival (PFS), overall survival (OS), and toxicity. Immune-related outcomes included immune ORR (iORR), immune CBR (iCBR), and immune PFS (iPFS). A two-stage design was used assuming: null=5% alternative=30%, n=6 in the first stage, 16 max, one-sided alpha=13%. RESULTS: The median number of prior therapy lines was 2 (range: 1-9). 3 of 21 patients attained confirmed partial response (PR) (ORR=14%). In addition, one patient had an unconfirmed PR; one, stable disease (SD)>6 months; one, immune-related RECIST (iRECIST) PR (iPR); and one patient attained iSD>6 months: clinical benefit rate (response or SD>6 months)=5/21 (24%), iORR=4/21 (19%), iCBR=7/21 (33%). The 6-month PFS was 24%; 6-month iPFS, 33%. The PFS for patients (N=7) with iRECIST clinical benefit were 57, 52, 18, 15, 13, 7, and 7 months. The 6-month OS was 76%; the median OS, was 15.8 months. The most common toxicities were fatigue (62%) and rash (38%), and the most common grade 3/4 immune-related adverse events were hepatic dysfunction (9.5%) and adrenal insufficiency (9.5%). Treatment-related adverse events leading to discontinuation of therapy in four patients (21%). There were no grade 5 adverse events. CONCLUSIONS: Ipilimumab plus nivolumab is active in refractory metastatic adrenocortical cancer meeting the primary endpoint of the study, with a 19% iORR and 33% iCBR (includes SD/iSD>6 months) and with the longest PFS/iPFS of 52 and 57 months. TRIAL REGISTRATION NUMBER: NCT02834013 (registered 15 July, 2016; https://clinicaltrials.gov/ct2/show/NCT02834013).

Histone acetylation risk model predicts prognosis and guides therapy selection in glioblastoma: implications for chemotherapy and anti-CTLA-4 immunotherapy.

BACKGROUND: Glioblastoma is characterized by high aggressiveness, frequent recurrence, and poor prognosis. Histone acetylation-associated genes have been implicated in its occurrence and development, yet their predictive ability in glioblastoma prognosis remains unclear. RESULTS: This study constructs a histone acetylation risk model using Cox and LASSO regression analyses to evaluate glioblastoma prognosis. We assessed the model's prognostic ability with univariate and multivariate Cox regression analyses. Additionally, immune infiltration was evaluated using ESTIMATE and TIMER algorithms, and the SubMAP algorithm was utilized to predict responses to CTLA4 inhibitor. Multiple drug databases were applied to assess drug sensitivity in high- and low-risk groups. Our results indicate that the histone acetylation risk model is independent and reliable in predicting prognosis. CONCLUSIONS: Low-risk patients showed higher immune activity and longer overall survival, suggesting anti-CTLA4 immunotherapy suitability, while high-risk patients might benefit more from chemotherapy. This model could guide personalized therapy selection for glioblastoma patients.

A combined radio-immunotherapy regimen eradicates late-stage tumors in mice.

Background: The majority of experimental approaches for cancer immunotherapy are tested against relatively small tumors in tumor-bearing mice, because in most cases advanced cancers are resistant to the treatments. In this study, we asked if even late-stage mouse tumors can be eradicated by a rationally designed combined radio-immunotherapy (CRI) regimen. Methods: CRI consisted of local radiotherapy, intratumoral IL-12, slow-release systemic IL-2 and anti- CTLA-4 antibody. Therapeutic effects of CRI against several weakly immunogenic and immunogenic mouse tumors including B78 melanoma, MC38 and CT26 colon carcinomas and 9464D neuroblastoma were evaluated. Immune cell depletion and flow cytometric analysis were performed to determine the mechanisms of the antitumor effects. Results: Tumors with volumes of 2,000 mm3 or larger were eradicated by CRI. Flow analyses of the tumors revealed reduction of T regulatory (Treg) cells and increase of CD8/Treg ratios following CRI. Rapid shrinkage of the treated tumors did not require T cells, whereas T cells were involved in the systemic effect against the distant tumors. Cured mice developed immunological memory. Conclusions: These findings underscore that rationally designed combination immunotherapy regimens can be effective even against large, late-stage tumors.

A novel doxorubicin/CTLA-4 blocker co-loaded drug delivery system improves efficacy and safety in antitumor therapy.

Doxorubicin's antitumor effectiveness may be constrained with ineffective tumor penetration, systemic adverse effects, as well as drug resistance. The co-loading of immune checkpoint inhibitors and doxorubicin into liposomes can produce synergistic benefits and address problems, including quick drug clearance, toxicity, and low drug penetration efficiency. In our previous study, we modified a nanobody targeting CTLA-4 onto liposomes (LPS-Nb36) to be an extremely potent CTLA-4 signal blocker which improve the CD8+ T-cell activity against tumors under physiological conditions. In this study, we designed a drug delivery system (LPS-RGD-Nb36-DOX) based on LPS-Nb36 that realized the doxorubicin and anti-CTLA-4 Nb co-loaded and RGD modification, and was applied to antitumor therapy. We tested whether LPS-RGD-Nb36-DOX could targets the tumor by in vivo animal photography, and more importantly, promote cytotoxic T cells proliferation, pro-inflammatory cytokine production, and cytotoxicity. Our findings demonstrated that the combination of activated CD8+ T cells with doxorubicin/anti-CTLA-4 Nb co-loaded liposomes can effectively eradicate tumor cells both in vivo and in vitro. This combination therapy is anticipated to have synergistic antitumor effects. More importantly, it has the potential to reduce the dose of chemotherapeutic drugs and improve safety.

Post-immunotherapy CTLA-4 Ig treatment improves antitumor efficacy.

Immune checkpoint therapies (ICT) improve overall survival of patients with cancer but may cause immune-related adverse events (irAEs) such as myocarditis. Cytotoxic T lymphocyte-associated antigen 4 immunoglobulin fusion protein (CTLA-4 Ig), an inhibitor of T cell costimulation through CD28, reverses irAEs in animal models. However, concerns exist about potentially compromising antitumor response of ICT. In mouse tumor models, we administered CTLA-4 Ig 1) concomitantly with ICT or 2) after ICT completion. Concomitant treatment reduced antitumor efficacy, while post-ICT administration improved efficacy without affecting frequency and function of CD8 T cells. The improved response was independent of the ICT used, whether CTLA-4 or PD-1 blockade. The frequency of Tregs was significantly decreased with CTLA-4 Ig. The resulting increased CD8/Treg ratio potentially underlies the enhanced efficacy of ICT followed by CTLA-4 Ig. This paradoxical mechanism shows that a CTLA-4 Ig regimen shown to reduce irAE severity does not compromise antitumor efficacy.

Treatment patterns and survival outcomes of patients admitted to the intensive care unit due to immune-related adverse events of immune checkpoint inhibitors.

INTRODUCTION: Severe immune-related adverse events (irAEs) due to immune checkpoint inhibitors (ICIs) can lead to admission to the intensive care unit (ICU). In this retrospective study, we determined the incidence, treatment patterns and survival outcomes of this patient population at a comprehensive cancer center. METHODS: All patients admitted to the ICU due to irAEs from ICI treatment between January 2015 and July 2022 were included. Descriptive statistics were reported on patient characteristics and treatment patterns during hospital admission. Overall survival (OS) from the time of ICU discharge to death was estimated using the Kaplan-Meier method. RESULTS: Over the study period, 5561 patients received at least one ICI administration, of which 32 patients (0.6%) were admitted to the ICU due to irAEs. Twenty patients were treated with anti-PD-1 plus anti-CTLA-4 treatment, whereas 12 patients were treated with ICI monotherapy. The type of irAEs were de novo diabetes-related ketoacidosis (n = 8), immune-related gastrointestinal toxicity (n = 8), myocarditis or myositis (n = 10), nephritis (n = 3), pneumonitis (n = 2), and myelitis (n = 1). The median duration of ICU admission was 3 days (interquartile range: 2-6 days). Three patients died during ICU admission. The median OS of the patients who were discharged from the ICU was 18 months (95% confidence interval, 5.0-NA). CONCLUSION: The incidence of irAEs leading to ICU admission in patients treated with ICI was low in this study. ICU mortality due to irAEs was low and a subset of this patient population even had long-term survival.

Efficacy and Safety of Programmed Death 1/Programmed Death-Ligand 1 Plus Cytotoxic T-Lymphocyte-Associated Antigen 4 Inhibitors for Advanced or Metastatic Non-Small Cell Lung Cancer: A Meta-analysis Based on Randomized Controlled Trials.

BACKGROUND: This meta-analysis aims to investigate the efficacy and safety of programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) combined with cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors for patients with advanced or metastatic non-small cell lung cancer (NSCLC). METHODS: Authors conducted a comprehensive search of PubMed, Embase, Cochrane Library, Web of Science, Scopus, and Medline for randomized controlled trials comparing the prognosis and safety of PD-1/PD-L1 plus CTLA-4 inhibitors with other therapies for advanced or metastatic NSCLC. Hazard ratios (HRs) and 95% confidence intervals (CIs) were used as effect sizes. The primary outcomes of this study were overall survival (OS) and progression-free survival. RESULTS: A total of 4943 patients diagnosed with stage III/IV advanced or metastatic NSCLC were included in the analysis of the 6 randomized controlled trials. The results showed that patients receiving dual immunotherapy with PD-1/PD-L1 plus CTLA-4 inhibitors had a longer survival time compared with the control group (HR = 0.88, P = 0.044). However, no statistically significant difference was observed in progression-free survival (HR = 0.95, P = 0.579). Subgroup analysis revealed better OS in the interventional group for patients aged >65 years (HR = 0.88, P = 0.076), smokers (HR = 0.81, P = 0.036), and those with a tumor mutational burden (TMB) ≥20 mut/Mb (HR = 0.66, P < 0.001). Conversely, the control group demonstrated superior OS in patients with TMB <20 mut/Mb (HR = 1.14, P = 0.048). In addition, the statistical results indicated a lower incidence rate of any-grade anemia in the dual immunotherapy group compared with the control group (RR = 0.32, P = 0.04). CONCLUSIONS: This meta-analysis demonstrates the effectiveness and safety of dual immunotherapy with PD-1/PD-L1 plus CTLA-4 inhibitors for treating advanced or metastatic NSCLC. Its efficacy is influenced by certain clinical and pathological factors, such as age, smoking status, and TMB.

Immune checkpoint inhibitors and SARS-CoV2 infection.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS­CoV­2) triggers coronavirus disease 2019 (COVID-19), which predominantly targets the respiratory tract. SARS-CoV-2 infection, especially severe COVID-19, is associated with dysregulated immune responses against the virus, including exaggerated inflammatory responses known as the cytokine storm, together with lymphocyte and NK cell dysfunction known as immune cell exhaustion. Overexpression of negative immune checkpoints such as PD-1 and CTLA-4 plays a considerable role in the dysfunction of immune cells upon SARS-CoV-2 infection. Blockade of these checkpoints has been suggested to improve the clinical outcome of COVID-19 patients by promoting potent immune responses against the virus. In the current review, we provide an overview of the potential of checkpoint inhibitors to induce potent immune responses against SARS-CoV-2 and improving the clinical outcome of severe COVID-19 patients.

Cancer cell plasticity defines response to immunotherapy in cutaneous squamous cell carcinoma.

Immune checkpoint blockade (ICB) approaches have changed the therapeutic landscape for many tumor types. However, half of cutaneous squamous cell carcinoma (cSCC) patients remain unresponsive or develop resistance. Here, we show that, during cSCC progression in male mice, cancer cells acquire epithelial/mesenchymal plasticity and change their immune checkpoint (IC) ligand profile according to their features, dictating the IC pathways involved in immune evasion. Epithelial cancer cells, through the PD-1/PD-L1 pathway, and mesenchymal cancer cells, through the CTLA-4/CD80 and TIGIT/CD155 pathways, differentially block antitumor immune responses and determine the response to ICB therapies. Accordingly, the anti-PD-L1/TIGIT combination is the most effective strategy for blocking the growth of cSCCs that contain both epithelial and mesenchymal cancer cells. The expression of E-cadherin/Vimentin/CD80/CD155 proteins in cSCC, HNSCC and melanoma patient samples predicts response to anti-PD-1/PD-L1 therapy. Collectively, our findings indicate that the selection of ICB therapies should take into account the epithelial/mesenchymal features of cancer cells.

irAE-colitis induced by CTLA-4 and PD-1 blocking were ameliorated by TNF blocking and modulation of gut microbial.

Immune-related adverse events, particularly colitis (irAE-colitis), are significant impediments to the advancement of immune checkpoint therapy. To address this, blocking TNF-α and modulating gut microbiota are effective strategies. However, their precise roles in irAE-colitis pathogenesis and potential reciprocal relationship remain unclear. An irAE-colitis model was established to evaluate the toxicity of DICB and the efficacy of Infliximab, validated through a tumor irAE-colitis mice model. Co-administration of Infliximab with DICB mitigates colitis and enhances efficacy. Analysis of fecal samples from mice reveals altered gut microbiota composition and function induced by irAE-colitis, restored by Infliximab. Notably, Bacteriodes abundance is significantly higher in irAE-colitis. Disruption of arachidonic acid and tyrosine metabolism, and steroid hormone biosynthesis is evident. Mechanistically, a regenerative feedback loop involving DICB, TNF-α and gut microbiota underlies irAE-colitis pathogenesis. In conclusion, Infliximab shows therapeutic effects against DICB toxicity, highlighting the unforeseen roles of gut microbiota and TNF-α in irAE-colitis.