DARPin-fused T cell engager for adenovirus-mediated cancer therapy.

Bispecific T cell engagers are a promising class of therapeutic proteins for cancer therapy. Their potency and small size often come with systemic toxicity and short half-life, making intravenous administration cumbersome. These limitations can be overcome by tumor-specific in situ expression, allowing high local accumulation while reducing systemic concentrations. However, encoding T cell engagers in viral or non-viral vectors and expressing them in situ ablates all forms of quality control performed during recombinant protein production. It is therefore vital to design constructs that feature minimal domain mispairing, and increased homogeneity of the therapeutic product. Here, we report a T cell engager architecture specifically designed for vector-mediated immunotherapy. It is based on a fusion of a designed ankyrin repeat protein (DARPin) to a CD3-targeting single-chain antibody fragment, termed DATE (DARPin-fused T cell Engager). The DATE induces potent T cell-mediated killing of HER2+ cancer cells, both as recombinantly produced therapeutic protein and as in situ expressed payload from a HER2+-retargeted high-capacity adenoviral vector (HC-AdV). We report remarkable tumor remission, DATE accumulation, and T cell infiltration through in situ expression mediated by a HER2+-retargeted HC-AdV in vivo. Our results support further investigations and developments of DATEs as payloads for vector-mediated immunotherapy.

Melanoma Clonal Heterogeneity Leads to Secondary Resistance after Adoptive Cell Therapy with Tumor-Infiltrating Lymphocytes.

Adoptive cell therapy (ACT) with tumor-infiltrating lymphocytes (TIL) is effective in patients with melanoma, although long-term responses seem restricted in patients who have complete remissions. Many patients develop secondary resistance to TIL-ACT but the involved mechanisms are unclear. In this study, we describe a case of secondary resistance to TIL-ACT possibly due to intratumoral heterogeneity and selection of a resistant tumor cell clone by the transferred T cells. To the best our knowledge, this is the first case of clonal selection of a pre-existing nondominant tumor cell clone; this report demonstrates the mechanism involved in secondary resistance to TIL-ACT that can potentially change current clinical practice because it advocates for T-cell collection from multiple tumor sites and analysis of tumor heterogeneity before treatment with TIL-ACT.

Autoimmunity Against Surfactant Protein B Is Associated with Pneumonitis During Checkpoint Blockade.

RATIONALE: Immune checkpoint inhibitor-related pneumonitis is a serious autoimmune event affecting up to 20% of patients with non-small cell lung cancer, yet the factors underpinning its development in some patients and not others are poorly understood. OBJECTIVES: To investigate the role of autoantibodies and autoreactive T cells against surfactant-related proteins in the development of pneumonitis. METHODS: The study cohort consisted of non-small cell lung cancer patients who gave blood samples before and during immune checkpoint inhibitor treatment. Serum was used for proteomics analyses and to detect autoantibodies present during pneumonitis. T cell stimulation assays and single-cell RNA sequencing were performed to investigate the specificity and functionality of peripheral autoreactive T cells. The findings were confirmed in a validation cohort comprising patients with non-small cell lung cancer and patients with melanoma. MEASUREMENTS AND MAIN RESULTS: Across both cohorts, patients who developed pneumonitis had higher pre-treatment levels of immunoglobulin G autoantibodies targeting surfactant protein-B. At the onset of pneumonitis, these patients also exhibited higher frequencies of CD4+ interferon-gamma-positive surfactant protein B-specific T cells, and expanding T cell clonotypes recognizing this protein, accompanied by a pro-inflammatory serum proteomic profile. CONCLUSIONS: Our data suggest that the co-occurrence of surfactant protein-B-specific immunoglobulin G autoantibodies and CD4+ T cells is associated with the development of pneumonitis during ICI therapy. Pre-treatment levels of these antibodies may represent a potential biomarker for elevated risk of developing pneumonitis and on-treatment levels may provide a diagnostic aid. This article is open access and distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives License 4.0 (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Regulation of sialic acid metabolism in cancer.

Sialic acid, the terminal structure of cell surface glycans, has essential functions in regulating immune response, cell-to-cell communication, and cell adhesion. More importantly, an increased level of sialic acid, termed hypersialylation, has emerged as a commonly observed phenotype in cancer. Therefore, targeting sialic acid ligands (sialoglycans) and their receptors (Siglecs) may provide a new therapeutic approach for cancer immunotherapy. We highlight the complexity of the sialic acid metabolism and its involvement in malignant transformation within individual cancer subtypes. In this review, we focus on the dysregulation of sialylation, the intricate nature of sialic acid synthesis, and clinical perspective. We aim to provide a brief insight into the mechanism of hypersialylation and how our understanding of these processes can be leveraged for the development of novel therapeutics.

Glioblastoma in the oldest old: Clinical characteristics, therapy, and outcome in patients aged 80 years and older.

Background: Incidence rates of glioblastoma in very old patients are rising. The standard of care for this cohort is only partially defined and survival remains poor. The aims of this study were to reveal current practice of tumor-specific therapy and supportive care, and to identify predictors for survival in this cohort. Methods: Patients aged 80 years or older at the time of glioblastoma diagnosis were retrospectively identified in 6 clinical centers in Switzerland and France. Demographics, clinical parameters, and survival outcomes were annotated from patient charts. Cox proportional hazards modeling was performed to identify parameters associated with survival. Results: Of 107 patients, 45 were diagnosed by biopsy, 30 underwent subtotal resection, and 25 had gross total resection. In 7 patients, the extent of resection was not specified. Postoperatively, 34 patients did not receive further tumor-specific treatment. Twelve patients received radiotherapy with concomitant temozolomide, but only 2 patients had maintenance temozolomide therapy. Fourteen patients received temozolomide alone, 35 patients received radiotherapy alone, 1 patient received bevacizumab, and 1 took part in a clinical trial. Median progression-free survival (PFS) was 3.3 months and median overall survival (OS) was 4.2 months. Among patients who received any postoperative treatment, median PFS was 3.9 months and median OS was 7.2 months. Karnofsky performance status (KPS) ≥70%, gross total resection, and combination therapy were associated with better outcomes. The median time spent hospitalized was 30 days, accounting for 23% of the median OS. End-of-life care was mostly provided by nursing homes (n = 20; 32%) and palliative care wards (n = 16; 26%). Conclusions: In this cohort of very old patients diagnosed with glioblastoma, a large proportion was treated with best supportive care. Treatment beyond surgery and, in particular, combined modality treatment were associated with longer OS and may be considered for selected patients even at higher ages.

Engagement of sialylated glycans with Siglec receptors on suppressive myeloid cells inhibits anticancer immunity via CCL2.

The overexpression of sialic acids on glycans, called hypersialylation, is a common alteration found in cancer cells. Sialylated glycans can enhance immune evasion by interacting with sialic acid-binding immunoglobulin-like lectin (Siglec) receptors on tumor-infiltrating immune cells. Here, we investigated the effect of sialylated glycans and their interaction with Siglec receptors on myeloid-derived suppressor cells (MDSCs). We found that MDSCs derived from the blood of lung cancer patients and tumor-bearing mice strongly express inhibitory Siglec receptors and are highly sialylated. In murine cancer models of emergency myelopoiesis, Siglec-E knockout in myeloid cells resulted in prolonged survival and increased tumor infiltration of activated T cells. Targeting suppressive myeloid cells by blocking Siglec receptors or desialylation strongly reduced their suppressive potential. We further identified CCL2 as a mediator involved in T-cell suppression upon interaction between sialoglycans and Siglec receptors on MDSCs. Our results demonstrated that sialylated glycans inhibit anticancer immunity by modulating CCL2 expression.

Effects of CTLA-4 Single Nucleotide Polymorphisms on Toxicity of Ipilimumab-Containing Regimens in Patients With Advanced Stage Melanoma.

Single nucleotide polymorphisms (SNPs) in the cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) gene, an inhibitor of T-cell priming, are associated with auto and alloimmunity. Studies implied a role for these SNPs as surrogate markers for immunotherapy-outcome in patients with melanoma. However, no predictive SNPs are defined to date. We analyzed different CTLA-4 SNPs in a large multicenter cohort of patients with ipilimumab-treated melanoma and investigated possible correlations with treatment-related outcomes. Archival blood and/or tumor tissue samples were collected from 361 patients with advanced-stage ipilimumab-treated (±nivolumab) in 6 Swiss and Dutch hospitals. Matrix-assisted laser desorption/ionization-time of flight mass spectrometry based DNA genotyping was performed for 10 different CTLA-4 SNPs: 49A>G, CT60G>A, Jo27T>C, Jo30G>A, Jo31G>T, -658C>T, -1722T>C, -1661A>G, 318C>T, and C>T rs1863800. Associations between different allele genotypes and occurrence of grade ≥3 adverse events (AEs) and survival were tested using univariable logistic regressions or Cox proportional hazard models. 262/361 (73%) patients could be analyzed; 65% of those were males, the median age was 58 years, 39% showed a partial or complete response, and 65% had ≥1 AEs. A TT-genotype of -1722T>C SNP was significantly associated with a lower incidence of grade ≥3 AEs ( P = 0.049), whereas the GG-genotype of CT60G>A correlated with a higher incidence of grade ≥3 AEs ( P = 0.026). The TT-genotype of Jo27T>C SNP ( P = 0.056) and GG-genotype of Jo31G>T ( P = 0.046) were associated with overall survival. CTLA-4 SNPs might predict treatment-related outcomes in patients with melanoma receiving ipilimumab. Confirmatory studies are needed to fully exploit those findings as predictive biomarkers for ipilimumab AEs.

Mutation-specific CAR T cells as precision therapy for IGLV3-21R110 expressing high-risk chronic lymphocytic leukemia.

The concept of precision cell therapy targeting tumor-specific mutations is appealing but requires surface-exposed neoepitopes, which is a rarity in cancer. B cell receptors (BCR) of mature lymphoid malignancies are exceptional in that they harbor tumor-specific-stereotyped sequences in the form of point mutations that drive self-engagement of the BCR and autologous signaling. Here, we use a BCR light chain neoepitope defined by a characteristic point mutation (IGLV3-21R110) for selective targeting of a poor-risk subset of chronic lymphocytic leukemia (CLL) with chimeric antigen receptor (CAR) T cells. We develop murine and humanized CAR constructs expressed in T cells from healthy donors and CLL patients that eradicate IGLV3-21R110 expressing cell lines and primary CLL cells, but neither cells expressing the non-pathogenic IGLV3-21G110 light chain nor polyclonal healthy B cells. In vivo experiments confirm epitope-selective cytolysis in xenograft models in female mice using engrafted IGLV3-21R110 expressing cell lines or primary CLL cells. We further demonstrate in two humanized mouse models lack of cytotoxicity towards human B cells. These data provide the basis for advanced approaches of resistance-preventive and biomarker-guided cellular targeting of functionally relevant lymphoma driver mutations sparing normal B cells.

Corticosteroid-resistant immune-related adverse events: a systematic review.

Immune checkpoint inhibitor (ICI) treatment has become an important therapeutic option for various cancer types. Although the treatment is effective, ICI can overstimulate the patient's immune system, leading to potentially severe immune-related adverse events (irAEs), including hepatitis, colitis, pneumonitis and myocarditis. The initial mainstay of treatments includes the administration of corticosteroids. There is little evidence how to treat steroid-resistant (sr) irAEs. It is mainly based on small case series or single case reports. This systematic review summarizes available evidence about sr-irAEs. We conducted a systematic literature search in PubMed. Additionally, we included European Society for Medical Oncology, Society for Immunotherapy of Cancer, National Comprehensive Cancer Network and American Society of Clinical Oncology Guidelines for irAEs in our assessment. The study population of all selected publications had to include patients with cancer who developed hepatitis, colitis, pneumonitis or myocarditis during or after an immunotherapy treatment and for whom corticosteroid therapy was not sufficient. Our literature search was not restricted to any specific cancer diagnosis. Case reports were also included. There is limited data regarding life-threatening sr-irAEs of colon/liver/lung/heart and the majority of publications are single case reports. Most publications investigated sr colitis (n=26), followed by hepatitis (n=21), pneumonitis (n=17) and myocarditis (n=15). There is most data for mycophenolate mofetil (MMF) to treat sr hepatitis and for infliximab, followed by vedolizumab, to treat sr colitis. Regarding sr pneumonitis there is most data for MMF and intravenous immunoglobulins (IVIG) while data regarding infliximab are conflicting. In sr myocarditis, most evidence is available for the use of abatacept or anti-thymocyte globulin (ATG) (both with or without MMF) or ruxolitinib with abatacept. This review highlights the need for prompt recognition and treatment of sr hepatitis, colitis, pneumonitis and myocarditis. Guideline recommendations for sr situations are not defined precisely. Based on our search, we recommend-as first line treatment-(1) MMF for sr hepatitis, (2) infliximab for sr colitis, followed by vedolizumab, (3) MMF and IVIG for sr pneumonitis and (4) abatacept or ATG (both with or without MMF) or ruxolitinib with abatacept for sr myocarditis. These additional immunosuppressive agents should be initiated promptly if there is no sufficient response to corticosteroids within 3 days.

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.

A phase Ib/II randomized, open-label drug repurposing trial of glutamate signaling inhibitors in combination with chemoradiotherapy in patients with newly diagnosed glioblastoma: the GLUGLIO trial protocol.

BACKGROUND: Glioblastoma is the most common and most aggressive malignant primary brain tumor in adults. Glioblastoma cells synthesize and secrete large quantities of the excitatory neurotransmitter glutamate, driving epilepsy, neuronal death, tumor growth and invasion. Moreover, neuronal networks interconnect with glioblastoma cell networks through glutamatergic neuroglial synapses, activation of which induces oncogenic calcium oscillations that are propagated via gap junctions between tumor cells. The primary objective of this study is to explore the efficacy of brain-penetrating anti-glutamatergic drugs to standard chemoradiotherapy in patients with glioblastoma. METHODS/DESIGN: GLUGLIO is a 1:1 randomized phase Ib/II, parallel-group, open-label, multicenter trial of gabapentin, sulfasalazine, memantine and chemoradiotherapy (Arm A) versus chemoradiotherapy alone (Arm B) in patients with newly diagnosed glioblastoma. Planned accrual is 120 patients. The primary endpoint is progression-free survival at 6 months. Secondary endpoints include overall and seizure-free survival, quality of life of patients and caregivers, symptom burden and cognitive functioning. Glutamate levels will be assessed longitudinally by magnetic resonance spectroscopy. Other outcomes of interest include imaging response rate, neuronal hyperexcitability determined by longitudinal electroencephalography, Karnofsky performance status as a global measure of overall performance, anticonvulsant drug use and steroid use. Tumor tissue and blood will be collected for translational research. Subgroup survival analyses by baseline parameters include segregation by age, extent of resection, Karnofsky performance status, O6-methylguanine DNA methyltransferase (MGMT) promotor methylation status, steroid intake, presence or absence of seizures, tumor volume and glutamate levels determined by MR spectroscopy. The trial is currently recruiting in seven centers in Switzerland. TRIAL REGISTRATION: NCT05664464. Registered 23 December 2022.

Phase 1 first-in-human dose-escalation study of ANV419 in patients with relapsed/refractory advanced solid tumors.

BACKGROUND: ANV419 is a stable antibody-cytokine fusion protein consisting of interleukin-2 (IL-2) fused to an anti-IL-2 monoclonal antibody that sterically hinders binding of IL-2 to the α subunit of its receptor but has selective affinity for the receptor ßγ subunits. Thus, ANV419 preferentially stimulates CD8+ effector T cells and natural killer cells which are associated with tumor killing, while minimizing the activation of immunosuppressive regulatory T cells. METHODS: ANV419-001 is an open-label, multicenter, phase 1 study to evaluate the safety, tolerability, maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D) of ANV419. Secondary objectives were to characterize the pharmacokinetics, pharmacodynamics and tumor response. Adult patients with advanced solid tumors and disease progression after ≥1 previous line of systemic therapy were enrolled. ANV419 was administered by intravenous infusion once every 2 weeks, with a planned treatment duration of 12 months. The dose escalation part of the study explored doses 3, 6 and 12 µg/kg as single patient cohorts followed by 24-364 µg/kg in a 3+3 design. Interim results are reported here (data cut-off: March 22, 2023). RESULTS: Forty patients were enrolled and received at least one dose of ANV419. The MTD and RP2D were determined to be 243 µg/kg. The most common ANV419-related treatment-emergent adverse events were Grade 1 and 2 fever (31 (77.5%)), chills (23 (57.5%), vomiting (14 (35.0%)), cytokine release syndrome and nausea (12 (30.0%) each). Transient and self-limiting lymphopenia due to lymphocyte redistribution was observed in all patients. In the RP2D cohort, Grade ≥3 thrombocytopenia and fever were reported by one patient (12.5%) each. All events were manageable with standard supportive care. At doses of 243 µg/kg (RP2D/MTD), the estimated T1/2 was approximately 12 hours. At ANV419 doses ≥108 µg/kg, 64% of patients had a best response of at least SD (15 SD and 1 confirmed PR). CONCLUSIONS: ANV419 at doses up to 243 µg/kg (the RP2D) was well tolerated and showed signs of antitumor activity in a heavily pretreated patient population with advanced solid tumors. TRIAL REGISTRATION NUMBER: NCT04855929.