Activity Of Immune Checkpoint Inhibitors Research Articles

LAG-3 : recent developments in combinational therapies in cancer.

The study of anticancer immune responses and in particular the action of immune checkpoint inhibitors that overcome T cell inhibition has revolutionized metastatic patients' care. Unfortunately, many patients are resistant to these innovative immunotherapies. Over the last decade, several immune checkpoint inhibitors, currently available in the clinic, have been developed, such as anti-PD-1/PD-L1 or anti-CTLA-4. More recently, other immune checkpoints have been characterized, among them lymphocyte activation gene 3 (LAG-3). LAG-3 has been the subject of numerous therapeutic studies and may be involved in cancer-associated immune resistance phenomena. This review summarizes the latest knowledge on LAG-3 as an immunotherapeutic target, particularly in combination with standard or innovative therapies. Indeed, many studies are looking at combining LAG-3 inhibitors with chemotherapeutic, immunotherapeutic, radiotherapeutic treatments, or adoptive cell therapies to potentiate their antitumor effects and/or to overcome patients' resistance. We will particularly focus on the association therapies that are currently in phase III clinical trials and innovative combinations in preclinical phase. These new discoveries highlight the possibility of developing other types of therapeutic combinations currently unavailable in the clinic, which could broaden the therapeutic spectrum of personalized medicine.

First-line avelumab plus chemotherapy in patients with advanced solid tumors: results from the phase 1b/2 JAVELIN Chemotherapy Medley study.

Chemotherapy can potentially enhance the activity of immune checkpoint inhibitors by promoting immune priming. The phase 1b/2 JAVELIN Chemotherapy Medley trial evaluated first-line avelumab + concurrent chemotherapy in patients with advanced urothelial carcinoma or nonsmall cell lung cancer (NSCLC). Avelumab 800 mg or 1200 mg was administered continuously every 3 weeks (Q3W) with standard doses of cisplatin + gemcitabine in patients with urothelial carcinoma, or carboplatin + pemetrexed in patients with nonsquamous NSCLC. Dual primary endpoints were dose-limiting toxicity (DLT; phase 1b) and confirmed objective response (phase 1b/2). In phase 1b, urothelial carcinoma and NSCLC cohorts received avelumab 800 mg (n=13 and n=6, respectively) or 1200 mg (n=6 each) + chemotherapy. In evaluable patients with urothelial carcinoma treated with avelumab 800 mg or 1200 mg + chemotherapy, DLT occurred in 1/12 (8.3%) and 1/6 (16.7%), respectively; no DLT occurred in the NSCLC cohort. In phase 2, 35 additional patients with urothelial carcinoma received avelumab 1200 mg + chemotherapy. Across all treated patients, safety profiles were similar irrespective of avelumab dose. Objective response rates (95% confidence internal) with avelumab 800 mg or 1200 mg + chemotherapy, respectively, across phase 1b/2, were 53.8% (25.1-80.8) and 39.0% (24.2-55.5) in urothelial carcinoma, and 50.0% (11.8-88.2) and 33.3% (4.3-77.7) in NSCLC. Preliminary efficacy and safety findings with avelumab + chemotherapy in urothelial carcinoma and NSCLC were consistent with previous studies of similar combination regimens. Conclusions about clinical activity are limited by small patient numbers. gov identifier, NCT03317496.

Abstract CT292: Phase II study of pembrolizumab in combination with lenvatinib in patients with triple negative breast cancer (TNBC), non-small cell lung cancer (NSCLC), and other tumor types and brain metastases

Abstract Background: Many patients develop brain metastasis during the course of their disease and it represents the cause of death in more than half of them. The prognosis and survival of patients with brain metastases remains poor with limited palliative treatment options. Thus, there is a need to develop new strategies for the therapeutic management of patients with brain metastases. Inflammatory stimuli originating from CNS tumors may increase the permeability of the blood-brain barrier and promote immune cell activation and infiltration into tumors. Several studies have demonstrated now the efficacy of immune checkpoint inhibitors in patients with melanoma with active brain metastases. The modulation of VEGF-mediated immune suppression via angiogenesis inhibition may augment the activity of immune checkpoint inhibitors. Lenvatinib is an oral, potent multiple receptor tyrosine kinase inhibitor that selectively inhibits VEGFRs, VEGFR1 (FLT1), VEGFR2 (KDR), and VEGFR3 (FLT4), in addition to other pro-angiogenic and oncogenic pathway-related receptor tyrosine kinases. The combination of lenvatinib and pembrolizumab is approved for patients with metastatic endometrial carcinoma and renal cancer, and it is investigated in other tumor types with promising preliminary results. We hypothesize that pembrolizumab and lenvatinib will be an effective treatment for TNBC, NSCLC, and other solid tumor types with brain metastases by decreasing angiogenic tumor activity and improving antitumor T-cell activity. Methods: This is a single-center, open-label, multi-cohort Phase II study evaluating the efficacy and safety of pembrolizumab in combination with lenvatinib in patients with solid tumors and brain metastases. The study has 3 cohorts: triple negative breast cancer (TNBC), non-small cell lung cancer (NSCLC), and other solid tumor types with established or preliminary clinical evidence of efficacy of programmed cell death-1 (PD-1) and angiogenesis inhibitors. Eligible patients will have at least 1 unirraditated or progressing brain metastasis of 0.5-2 cm on brain MRI. The study is conducted using a Simon’s optimal two-stage design, and approximately 87 patients will be enrolled concurrently (n=29 per cohort). Pembrolizumab (200 mg intravenously on Day 1 of each cycle) and lenvatinib (20 mg orally once daily) are administered in 21-day cycles for a maximum of 24 months. The primary endpoint is intracranial objective response rate at 4 months as assessed by the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Exploratory analyses will include evaluation of tissue and blood-based immune-related correlates of response to the pembrolizumab and lenvatinib combination. The first patient was enrolled in January 2022 and accrual of patients is ongoing (NCT05064280). Citation Format: Ecaterina E. Dumbrava, Emma J. Montazari, Uyen M. Vu, Tiantian Cai, Mehmet Altan, Nuhad K. Ibrahim, Debra N. Yeboa, Jing Li, Frederick F. Lang, Gisela Sanchez, Isabella C. Glitza, Barbara J. O'Brien, Rashmi K. Murthy, Jianbo Wang, Tanisha T. Darko, Denisse Velazquez, Komal Shah, Funda Meric-Bernstam, Hussein Tawbi, Jordi Rodon. Phase II study of pembrolizumab in combination with lenvatinib in patients with triple negative breast cancer (TNBC), non-small cell lung cancer (NSCLC), and other tumor types and brain metastases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr CT292.

Prospective Assessment of Fluorine-18-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography (FDG-PET/CT) for Early Identification of Checkpoint-Inhibitor-Induced Pseudoprogression.

The activity of immune checkpoint inhibitors (ICIs) in patients with metastatic melanoma is often monitored using fluorine-18-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) scans. However, distinguishing disease progression (PD) from pseudoprogression (PsPD), where increased FDG uptake might reflect immune cell activity rather than tumor growth, remains a challenge. This prospective study compared the efficacy of dual-time point (DTP) FDG-PET/CT with modified response criteria (PERCIMT) in differentiating PsPD from PD. From July 2017-January 2021, 41 patients suspected to have PsPD on an evaluation scan were prospectively included (29 evaluable). A subsequent DTP FDG-PET/CT scan was conducted within 14 days, followed by a confirmatory FDG-PET/CT scan. Additionally, PERCIMT were applied. DTP FDG-PET/CT identified 24% with PsPD and 76% with PD. Applying PERCIMT criteria, 69% showed PsPD, while 31% had PD. On follow-up, 10 patients (34%) demonstrated confirmed PsPD, while 19 (66%) exhibited PD. The sensitivity and specificity of DTP FDG-PET/CT were 20% and 74%, respectively, and for PERCIMT this was 80% and 37%, respectively. Our findings suggest limited efficacy of DTP FDG-PET/CT in distinguishing PsPD from PD in ICI-treated patients with metastatic melanoma. The use of PERCIMT could complement clinical assessment and be incorporated in multidisciplinary team conferences for enhanced decision-making.

Phase 2 study of pembrolizumab plus lenvatinib and belzutifan in patients with metastatic esophageal squamous cell carcinoma.

TPS425 Background: Initial signal finding studies demonstrated promising antitumor activity with the anti–PD-1 antibody pembrolizumab in combination with the anti-angiogenic multikinase inhibitor lenvatinib in patients with advanced gastric cancer or head and neck squamous cell carcinoma. Because hypoxia is common in many solid tumors and is known to induce an immunosuppressive tumor microenvironment, targeting hypoxia-inducible factor-2 alpha (HIF-2α) may enhance the activity of immune checkpoint inhibitors. The ongoing phase 2 LITESPARK-016 study (NCT04976634) is evaluating the combination of pembrolizumab plus lenvatinib and the HIF-2α inhibitor belzutifan (MK-6482) in multiple solid tumors. LITESPARK-016 includes 2 esophageal squamous cell carcinoma cohorts: one enrolling patients with immunotherapy-naive and the other enrolling patients with immunotherapy-resistant esophageal squamous cell carcinoma, cohorts F and G, respectively. We report the methodology for these cohorts. Methods: In this phase 2, open-label, multicenter study, eligible patients in the esophageal squamous cell carcinoma cohorts have histologically or cytologically confirmed metastatic disease and have tumors that are either immunotherapy-naive with disease progression on 1 prior line of standard systemic therapy (cohort F) or immunotherapy-resistant with disease progression during or after 1 prior line of treatment that contained an anti–PD-1/PD-L1 therapy (cohort G). Patients must be aged at least 18 years, have measurable disease per RECIST v1.1 (verified by BICR) with no radiographic evidence of major blood vessel encasement or intratumoral cavitation, ECOG PS of 0 to 1, and an archival/new tumor sample for biomarker analysis. Patients in cohort F receive triple therapy with pembrolizumab plus lenvatinib plus belzutifan; patients in cohort G are randomized 1:1 to receive either the same triple therapy or doublet therapy with pembrolizumab plus lenvatinib. The planned starting doses are pembrolizumab 400 mg given intravenously every 6 weeks, lenvatinib 20 mg orally once daily, and belzutifan 120 mg orally once daily. Treatment will continue for up to 2 years (for pembrolizumab) or until PD or discontinuation criteria are met. Approximately 30 patients will be enrolled in cohort F and in each arm of cohort G (approximately 90 total patients), with potential expansion of up to 70 additional patients in cohort F and each treatment arm of cohort G after safety/efficacy review with at least 6 months follow-up. The primary endpoints in cohorts F and G are safety (AEs, treatment discontinuation due to AEs) and ORR per RECIST v1.1 by BICR. Secondary endpoints are duration of response, disease control rate, and PFS per RECIST v1.1 by BICR, and OS. Assessment of biomarkers is an exploratory objective. Enrollment for this study began in September 2022 and is ongoing across 48 global sites. Clinical trial information: NCT04976634 .

Helicobacter pylori infection and response of gastric cancer to immunotherapy.

277 Background: Helicobacter pylori is a known risk factor for gastric cancer, possibly via the PD-1/L1 pathway. Some suggest that H. pylori infection may counteract the action of immune checkpoint inhibitors in few studies with limited sample size. This study explores the effects of H. pylori infection status on survival outcomes in patients with gastric cancer. Methods: This single-center, retrospective chart review included patients with gastric adenocarcinoma between June 1985 and August 2022. Patients with different histological subtypes were excluded. Primary variables of interest included H. pylori infection status and treatment with ICIs. Other clinical information included demographics, cancer histology, the presence of other cancers, and vital status. Results: 2,930 patients were included in the initial analysis. 206 (7.0%) received ICIs, 196 (6.7%) had prior H. pylori infection, and 1,037 (35.4%) had a mucinous subtype. Mucinous cancer subtypes were associated with improved survival (p<0.05) at 3 and 5 years compared to non-mucinous adenocarcinomas. Mucinous cancers demonstrated better survival outcomes than non-mucinous at 10 years, but only among H. pylori-positive patients (p=0.013). H. pylori positivity was associated with worse survival at 3 years (OR: 2.0, p=0.041) among patients taking ICIs but not for patients not receiving ICIs (OR: 0.8; p=0.325). Conclusions: H. pylori infection may negatively impact the therapeutic effect of ICIs. These findings suggest H. pylori infection may be an obstacle to successful immunotherapy and may interact with cancer subtypes to differentially impact survival. Future studies are needed to validate the potential prognostic value of H. pylori positivity in gastric cancer.

Multiplex Immunofluorescence Captures Progressive Immune Exhaustion with Advancing Penile Squamous Cell Cancer Stage.

Penile squamous cell carcinoma (PSCC) is a rare and deadly malignancy. Therapeutic advances have been stifled by a poor understanding of disease biology. Specifically, the immune microenvironment is an underexplored component in PSCC and the activity of immune checkpoint inhibitors observed in a subset of patients suggests immune escape may play an important role in tumorigenesis. Herein, we explored for the first time the immune microenvironment of 57 men with PSCC and how it varies with the presence of human papillomavirus (HPV) infection and across tumor stages using multiplex immunofluorescence of key immune cell markers. We observed an increase in the density of immune effector cells in node-negative tumors and a progressive rise in inhibitory immune players such as type 2 macrophages and upregulation of the PD-L1 checkpoint in men with N1 and N2-3 disease. There were no differences in immune cell densities with HPV status.

Variable PD-1 glycosylation modulates the activity of immune checkpoint inhibitors.

Monoclonal antibodies targeting the immune checkpoint PD-1 have provided significant clinical benefit across a number of solid tumors, with differences in efficacy and toxicity profiles possibly related to their intrinsic molecular properties. Here, we report that camrelizumab and cemiplimab engage PD-1 through interactions with its fucosylated glycan. Using a combination of protein and cell glycoengineering, we demonstrate that the two antibodies bind preferentially to PD-1 with core fucose at the asparagine N58 residue. We then provide evidence that the concentration of fucosylated PD-1 in the blood of non-small-cell lung cancer patients varies across different stages of disease. This study illustrates how glycoprofiling of surface receptors and related circulating forms can inform the development of differentiated antibodies that discriminate glycosylation variants and achieve enhanced selectivity, and paves the way toward the implementation of personalized therapeutic approaches.

23P Circulating immune cells and activity of immune checkpoint inhibitors in metastatic renal cell carcinoma

23P Circulating immune cells and activity of immune checkpoint inhibitors in metastatic renal cell carcinoma

Advances in the treatment of gastric cancer: 2022-2023.

To review 2022-2023 studies in gastric cancer. Important studies report the role of laparoscopic surgery in gastric cancer, the activity of immune checkpoint inhibitors in metastatic, locally advanced and adjuvant therapy in gastric cancer, and the effectiveness of zolbetuximab in claudin 18.2-positive metastatic disease. From the Japanese JLSSG0901 Trial, equivalent survival was reported for laparoscopically assisted versus conventional open gastrectomy. Adding nivolumab to adjuvant chemotherapy in resected stage III gastric cancer failed to improve 3-year disease-free survival over chemotherapy alone. Ipilimumab and nivolumab as preoperative therapy in MSI-high gastric cancer resulted in a high rate of pathologic complete response. Trastuzumab added to chemoradiotherapy and surgery in HER2-positive locally advanced esophageal and gastroesophageal junction adenocarcinoma did not improve overall survival over chemoradiotherapy and surgery alone. Adding pembrolizumab to trastuzumab/chemotherapy in metastatic HER2-positive gastric cancer improved antitumor response rate. Addition of zolbetuximab, an antibody targeting claudin 18.2, to first-line chemotherapy in metastatic claudin 18.2-positive gastric cancer improved overall survival. Immune checkpoint inhibition has a role in locally advanced MSI-high and metastatic gastric cancer. Laparoscopic gastrectomy is acceptable in gastric cancer. Zolbetuximab in metastatic gastric cancer will emerge as a new therapy option.

Immunotherapy for Colorectal Cancer with High Microsatellite Instability: The Ongoing Search for Biomarkers.

Microsatellite instability (MSI) is a biological condition associated with inflamed tumors, high tumor mutational burden (TMB), and responses to immune checkpoint inhibitors. In colorectal cancer (CRC), MSI tumors are found in 5% of patients in the metastatic setting and 15% in early-stage disease. Following the impressive clinical activity of immune checkpoint inhibitors in the metastatic setting, associated with deep and long-lasting responses, the development of immune checkpoint inhibitors has expanded to early-stage disease. Several phase II trials have demonstrated a high rate of pathological complete responses, with some patients even spared from surgery. However, in both settings, not all patients respond and some responses are short, emphasizing the importance of the ongoing search for accurate biomarkers. While various biomarkers of response have been evaluated in the context of MSI CRC, including B2M and JAK1/2 mutations, TMB, WNT pathway mutations, and Lynch syndrome, with mixed results, liver metastases have been associated with a lack of activity in such strategies. To improve patient selection and treatment outcomes, further research is required to identify additional biomarkers and refine existing ones. This will allow for the development of personalized treatment approaches and the integration of novel therapeutic strategies for MSI CRC patients with liver metastases.

Cavitation-Mediated Immunomodulation and Its Use with Checkpoint Inhibitors.

The promotion of anti-tumour immune responses can be an effective route to the complete remission of primary and metastatic tumours in a small proportion of patients. Hence, researchers are currently investigating various methods to further characterise and enhance such responses to achieve a beneficial impact across a wider range of patients. Due to its non-invasive, non-ionising, and targetable nature, the application of ultrasound-mediated cavitation has proven to be a popular method to enhance the delivery and activity of immune checkpoint inhibitors. However, to optimise this approach, it is important to understand the biological and physical mechanisms by which cavitation may promote anti-tumour immune responses. Here, the published literature relating to the role that cavitation may play in modulating anti-tumour immunity is therefore assessed.

Tumor microenvironment modifications induced by afatinib in squamous cell carcinoma of the head and neck - a window-of-opportunity study (EORTC90111-24111).

The EORTC-90111-24111 phase II window study evaluated afatinib versus no preoperative treatment in patients with primary squamous cell carcinoma of the head and neck (HNSCC). We investigated afatinib-induced tumor and microenvironment modifications by comparing pre- and post-treatment tumor biopsies. Thirty treatment-naïve patients with primary HNSCC were randomized. Twenty-five patients received afatinib for 14 days before surgery (40mg 1x/day) and five patients were attributed to the control arm. Biopsies were taken at work-up and during surgery. Good quality RNA samples were used for omics analyses. The control arm was enlarged by samples coming from our previous similar window study (Schmitz et al. 2013). Immunohistochemistry analyses of afatinib-treated tumor biopsies showed a decrease in pEGFR (P≤.05) and pERK (P≤.05); an increase in CD3+ (P≤.01) and CD8+ (P≤.01) T-cell infiltration, and in CD3+ (P≤.05) T-cell density. RNA sequencing analyses of afatinib-treated tumor samples showed upregulation of inflammatory genes and increased expression scores of signatures predictive of response to PD-1 blockade (P≤.05). In post-treatment biopsies of afatinib-treated patients, two clusters were observed. Cluster 1 showed a higher expression of markers and gene sets implicated in epithelial-to-mesenchymal transition (EMT) and activation of cancer-associated fibroblasts (CAFs) compared to cluster 2 and controls. Short-term treatment with afatinib in primary HNSCC induces CD3+ and CD8+ tumor infiltration and, in some patients, EMT and CAFs activation. These results open perspectives to overcome resistance mechanisms to anti-HER therapy and to potentiate the activity of immune checkpoint inhibitors.

ALK peptide vaccination restores the immunogenicity of ALK-rearranged non-small cell lung cancer.

Anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC) is treated with ALK tyrosine kinase inhibitors (TKIs), but the lack of activity of immune checkpoint inhibitors (ICIs) is poorly understood. Here, we identified immunogenic ALK peptides to show that ICIs induced rejection of ALK+ tumors in the flank but not in the lung. A single-peptide vaccination restored priming of ALK-specific CD8+ T cells, eradicated lung tumors in combination with ALK TKIs and prevented metastatic dissemination of tumors to the brain. The poor response of ALK+ NSCLC to ICIs was due to ineffective CD8+ T cell priming against ALK antigens and is circumvented through specific vaccination. Finally, we identified human ALK peptides displayed by HLA-A*02:01 and HLA-B*07:02 molecules. These peptides were immunogenic in HLA-transgenic mice and were recognized by CD8+ T cells from individuals with NSCLC, paving the way for the development of a clinical vaccine to treat ALK+ NSCLC.

Immune-related adverse events of immune checkpoint inhibitors: a review.

Since the first Immune Checkpoint Inhibitor was developed, tumor immunotherapy has entered a new era, and the response rate and survival rate of many cancers have also been improved. Despite the success of immune checkpoint inhibitors, resistance limits the number of patients who can achieve a lasting response, and immune-related adverse events complicate treatment. The mechanism of immune-related adverse events (irAEs) is unclear. We summarize and discuss the mechanisms of action of immune checkpoint inhibitors, the different types of immune-related adverse events and their possible mechanisms, and describe possible strategies and targets for prevention and therapeutic interventions to mitigate them.

Safety and Activity of Immune Checkpoint Inhibitors in People Living With HIV and Cancer: A Real-World Report From the Cancer Therapy Using Checkpoint Inhibitors in People Living With HIV-International (CATCH-IT) Consortium.

Compared with people living without HIV (PWOH), people living with HIV (PWH) and cancer have traditionally been excluded from immune checkpoint inhibitor (ICI) trials. Furthermore, there is a paucity of real-world data on the use of ICIs in PWH and cancer. This retrospective study included PWH treated with anti-PD-1- or anti-PD-L1-based therapies for advanced cancers. Kaplan-Meier method was used to estimate overall survival (OS) and progression-free survival (PFS). Objective response rates (ORRs) were measured per RECIST 1.1 or other tumor-specific criteria, whenever feasible. Restricted mean survival time (RMST) was used to compare OS and PFS between matched PWH and PWOH with metastatic NSCLC (mNSCLC). Among 390 PWH, median age was 58 years, 85% (n = 331) were males, 36% (n = 138) were Black; 70% (n = 274) received anti-PD-1/anti-PD-L1 monotherapy. Most common cancers were NSCLC (28%, n = 111), hepatocellular carcinoma ([HCC]; 11%, n = 44), and head and neck squamous cell carcinoma (HNSCC; 10%, n = 39). Seventy percent (152/216) had CD4+ T cell counts ≥200 cells/µL, and 94% (179/190) had HIV viral load <400 copies/mL. Twenty percent (79/390) had any grade immune-related adverse events (irAEs) and 7.7% (30/390) had grade ≥3 irAEs. ORRs were 69% (nonmelanoma skin cancer), 31% (NSCLC), 16% (HCC), and 11% (HNSCC). In the matched mNSCLC cohort (61 PWH v 110 PWOH), 20% (12/61) PWH and 22% (24/110) PWOH had irAEs. Adjusted 42-month RMST difference was -0.06 months (95% CI, -5.49 to 5.37; P = .98) for PFS and 2.23 months (95% CI, -4.02 to 8.48; P = .48) for OS. Among PWH, ICIs demonstrated differential activity across cancer types with no excess toxicity. Safety and activity of ICIs were similar between matched cohorts of PWH and PWOH with mNSCLC.

Redox Signaling Modulates Activity of Immune Checkpoint Inhibitors in Cancer Patients.

Although immunotherapy is already a staple of cancer care, many patients may not benefit from these cutting-edge treatments. A crucial field of research now focuses on figuring out how to improve treatment efficacy and assess the resistance mechanisms underlying this uneven response. For a good response, immune-based treatments, in particular immune checkpoint inhibitors, rely on a strong infiltration of T cells into the tumour microenvironment. The severe metabolic environment that immune cells must endure can drastically reduce effector activity. These immune dysregulation-related tumour-mediated perturbations include oxidative stress, which can encourage lipid peroxidation, ER stress, and T regulatory cells dysfunction. In this review, we have made an effort to characterize the status of immunological checkpoints, the degree of oxidative stress, and the part that latter plays in determining the therapeutic impact of immunological check point inhibitors in different neoplastic diseases. In the second section of the review, we will make an effort to assess new therapeutic possibilities that, by affecting redox signalling, may modify the effectiveness of immunological treatment.

Abstract 4557: 3D-EXpress platform utilizing tumoroids from patients with MSS and MSI-H tumors allows rapid assessment of anti-tumor activity of immune checkpoint inhibitors and development of clinically relevant biomarkers of treatment response

Abstract Introduction: Recent studies showed that patients with deficient mismatch repair(dMMR)/microsatellite instability-high (MSI-H) tumors, have higher sensitivity to immune checkpointinhibitors (ICIs) compared to patients with microsatellite-stable (MSS)/microsatellite instability-low(MSI-L) tumors. However, the mechanisms of treatment responsiveness and resistance is not wellunderstood. Here, we used a novel 3D-EXpress ex vivo fresh patient tumoroid platform to assess theefficacy of nivolumab/ipilimumab combination therapy in tumors with known MSS/MSI-H status andperformed correlative studies. Materials and Methods: All tumor samples were obtained with patient consent and relevant IRBapproval. Tumoroids measuring 150 µm in size retaining tumor cell heterogeneity, tumor-residentimmune cells, stromal components, and cell-extracellular matrix interaction were prepared frompatients with endometrial and colorectal tumors among others. Tumoroid aliquots were cryopreservedin Nilogen’s tumoroid Biorepository for future studies. For the 3D-EXpress studies cryopreservedtumoroids were selected based on MSS/MSI-H status and treated ex vivo with nivolumab andipilimumab alone and in combinations for 72h. Tumor responses to treatments were evaluated by aproprietary tumor cell killing assay and changes in tumor immune microenvironment. Furthermore,tumor PD-L1 expression levels were analyzed on the associated TMA slides. Results: Treatment-induced tumor cell killing activity in intact tumoroids was assessed by a 3D high-content confocal imaging technique using a proprietary algorithm for data analysis. The impact of exvivo treatment by nivolumab and/or ipilimumab on tumor resident immune cell populations wasmonitored by a multiplex cytokine release assay analyzing release of GM-CSF, sCD137, IFNγ, sFas, sFasL,Granzyme A, Granzyme B, IL-2, IL-4, IL-5, IL-6, IL-10, IL-13, MIP-1α, MIP-1β, TNF-α, and Perforin usingculture supernatants isolated from treated tumoroid samples. Based on the ex vivo responses tumorswere assigned to treatment sensitive and resistant groups and correlative analyses were performed withindividual tumors’ innate and adaptive immune cell populations detected by a 21-color flow cytometrypanel, in addition to tumor MSS/MSI-H and p53 status, and detailed clinicopathologic data readilyavailable for the tumors cryopreserved in the Biorepository. Conclusion: The 3D-Express platform, using cryopreserved 3D tumoroids with intact TME is an effectivetool for the assessment of rational combinations which may prove relevant in the treatment of solidtumors. Furthermore, we believe this platform is a useful tool for the pre-clinical assessment of specifictherapeutic regimens designed for individualized patient care. Citation Format: Brittney Ruedlinger, Seth Currlin, Sharon Camacho, Alliyah Humphrey, Jared Ehrhart, Soner Altiok. 3D-EXpress platform utilizing tumoroids from patients with MSS and MSI-H tumors allows rapid assessment of anti-tumor activity of immune checkpoint inhibitors and development of clinically relevant biomarkers of treatment response. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 4557.

Efficacy and safety of neoadjuvant immune checkpoint inhibitors in patients with localized mismatch repair deficient colorectal cancer: A systematic review.

149 Background: Clinical data demonstrating remarkable anti-tumor activity of immune checkpoint inhibitors (ICI) in patients with mismatch repair deficient (dMMR) metastatic colorectal cancer (CRC) and preclinical data suggesting enhanced efficacy of ICIs in the neoadjuvant setting than in the adjuvant setting led to numerous studies with neoadjuvant ICI in various tumor types including in dMMR CRC. We performed a systematic literature review of the published studies reporting the efficacy and safety of neoadjuvant ICIs in patients with localized dMMR CRC. Methods: Medline and Embase were searched for eligible case reports, case series, and clinical trial reports. Eligibility criteria included: 1. patients aged 18 years or older, 2. localized dMMR CRC, and 3. received neoadjuvant therapy primarily with ICI. Patients receiving radiation or chemotherapy along with ICI were excluded. The systematic review was conducted according to the PRISMA harms guidelines. Results: The database search yielded 143 citations which were reviewed by 3 authors (UG, KV, and SC), and 14 citations fulfilled all criteria for inclusion. The analysis included 173 patients with colon cancer (CC) and 19 with rectal cancer (RC). Among the patients with CC, 41 (24 %) received single-agent programmed death 1 (PD-1) blocker, and 132 (76 %) received dual blockade with an anti-PD-1 agent plus an anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) agent. Resection was performed in 171/173 (99%) patients, and 117/171 (69%) achieved complete pathological response (pCR). After median follow-up ranging between 8 and 15 months, none of the patients experienced cancer relapse. Among patients with RC, 16/19 (84%) received a PD-1 blocker, and 3 (16%) received dual PD-1 plus CTLA-4 blocker. Complete clinical response (cCR) was reported in 14/19 (74%) patients, and of the 5 patients who underwent surgery, 4 (80%) achieved pCR. All patients remained progression-free after median follow-up ranging from 6 to 12 months. Cancer progression or death on neoadjuvant ICI was not reported in any studies with CC or RC patients, and only two studies reported grade 3+ toxicity in 3% of CC patients. Conclusions: Neoadjuvant therapy with ICIs results in a remarkably high rate of clinical and pathological tumor regression with negligible safety concerns in patients with dMMR localized CRC. Well-designed clinical trials with long-term follow-up are needed to evaluate the organ-sparing potential of neoadjuvant ICI therapy in patients with dMMR CRC.

Implication of the Gut Microbiome and Microbial-Derived Metabolites in Immune-Related Adverse Events: Emergence of Novel Biomarkers for Cancer Immunotherapy.

Immune checkpoint inhibitors (ICIs) have changed how we think about tumor management. Combinations of anti-programmed death ligand-1 (PD-L1) immunotherapy have become the standard of care in many advanced-stage cancers, including as a first-line therapy. Aside from improved anti-tumor immunity, the mechanism of action of immune checkpoint inhibitors (ICIs) exposes a new toxicity profile known as immune-related adverse effects (irAEs). This novel toxicity can damage any organ, but the skin, digestive and endocrine systems are the most frequently afflicted. Most ICI-attributed toxicity symptoms are mild, but some are severe and necessitate multidisciplinary side effect management. Obtaining knowledge on the various forms of immune-related toxicities and swiftly changing treatment techniques to lower the probability of experiencing severe irAEs has become a priority in oncological care. In recent years, there has been a growing understanding of an intriguing link between the gut microbiome and ICI outcomes. Multiple studies have demonstrated a connection between microbial metagenomic and metatranscriptomic patterns and ICI efficacy in malignant melanoma, lung and colorectal cancer. The immunomodulatory effect of the gut microbiome can have a real effect on the biological background of irAEs as well. Furthermore, specific microbial signatures and metabolites might be associated with the onset and severity of toxicity symptoms. By identifying these biological factors, novel biomarkers can be used in clinical practice to predict and manage potential irAEs. This comprehensive review aims to summarize the clinical aspects and biological background of ICI-related irAEs and their potential association with the gut microbiome and metabolome. We aim to explore the current state of knowledge on the most important and reliable irAE-related biomarkers of microbial origin and discuss the intriguing connection between ICI efficacy and toxicity.