Citations

2531 Background: The immune co-stimulatory receptor OX40 is expressed on CD4+ T cells, including regulatory T cells (Tregs). First generation OX40 agonists faced limitations from interference with endogenous OX40-OX40L binding, leading to decreased surface OX40 levels on T cells. Distinguished by its unique epitope on OX40, the novel next generation IgG1 monoclonal antibody (mAb) HFB301001 facilitates agonistic activity without impeding endogenous OX40 ligand binding. This allows for effective co-stimulation of T cells without diminishing OX40 levels. Additionally, HFB301001 exhibited superior in vivoanti-tumor activity and ability to enhance effector CD8+ T cell function compared to a benchmark first generation OX40 agonist in preclinical studies. Here, we report initial data of an ongoing dose-escalation study (NCT05229601) of HFB301001 in patients (pts) with advanced solid tumors. Methods: A Phase I trial designed to evaluate safety, pharmacokinetics (PK), pharmacodynamics (PD), and preliminary efficacy of HFB301001. Eligible pts ≥18 years old (ECOG PS 0-1) with advanced solid tumors are enrolled in 4 different dose cohorts in monotherapy (Q4W) dose escalation. Solid tumor types were selected using Drug Intelligent Science (DIS®), employing integrative bulk and single cell RNAseq (scRNAseq) analyses to confirm and prioritize prospective targets in specific immune cell types. Sequential analysis of peripheral blood and tumor tissue biomarkers is performed. Radiographic response is assessed every 8 weeks. Results: As of January 06, 2024, 26 pts were enrolled, all having received prior systemic therapy (median 2, range 1-4); 81% received prior checkpoint inhibitor treatment. The majority of pts (77%) were male, median age was 62.5 years (range 41-78). Treatment-related adverse events (TRAEs) occurred in 34.6% of pts, none ≥ grade 3. Common TRAEs included rash (19%), pruritis (12%) and arthralgia (8%). No dose-limiting toxicities were observed. Preliminary results demonstrate dose-proportional increases in maximum concentration, typical mAb volume of distribution, and nonlinear clearance. On treatment biopsies revealed expansion of both natural killer and cytotoxic CD8+ T cells, with no notable expansion of Tregs. Analysis of peripheral blood by scRNAseq and immunophenotyping revealed expansion of cytotoxic CD8+T cells relative to CD4+ T cells post treatment. Preliminary efficacy analysis indicates a disease-control rate (DCR) of > 60% with greatest effect seen in hepato-cellular and renal cell carcinoma. Median time on treatment was 1.9 months (range 0.9-17 months). Conclusions: HFB301001 demonstrates a favorable safety profile, dose-dependent PK and PD immunomodulation, and DCR in heavily pretreated solid tumors. HFB301001 warrants further evaluation and expansion in specific tumor types is planned. Clinical trial information: NCT05229601 .

12065 Background: Incidence of cancer, including colorectal, breast, pancreas, kidney, and uterine cancer, is increasing in younger populations. Adolescents and young adults (AYA, defined as age 15-39) with cancer face unique challenges. This study aimed to characterize how symptom burden differs between AYA and non-AYA (aged 40+) patients with cancer. Methods: We performed a subgroup analysis of the E2C2 study, a cluster-randomized, pragmatic trial examining the effectiveness of routine symptom assessment and guideline-based management on patient-centered and healthcare utilization metrics during and following cancer treatment. Six symptoms [Sleep disturbance, Pain, Physical function impairment, Anxiety, Depression, and Energy deficit/fatigue (SPPADE)] were evaluated using 11-point numerical rating scales (NRS). Symptom severity was classified as mild (0-3), moderate (4-6), or severe (7-10). We conducted a subgroup analysis of symptom burden among AYA patients (defined as age 18-39 in this study), using their first-reported NRS scores. Results: The E2C2 cohort included 2,598 AYA patients and 38,061 non-AYA patients who completed >1 SPPADE NRS on at least one survey. AYA patients were more likely than non-AYA patients to report severe anxiety ( p<0.0001) and depression ( p<0.0001) (Table). Non-AYA patients were more likely to report severe pain ( p=0.02179), fatigue ( p=0.0022), and physical function limitations ( p<0.0001). Sociodemographic differences were also noted. A higher proportion of AYA patients held a bachelor’s degree or higher (38% vs 28%), were employed (73% vs 37%), and lived in an urban setting (67% vs 56%), compared to non-AYA patients. Non-AYA patients were more likely to have government insurance (63% vs 21%) and to be married (72% vs 59%). Conclusions: AYA patients with cancer were more likely to report severe depression and anxiety compared to their counterparts age 40 and above, underscoring the need for targeted and tailored psycho-oncology care for this population. [Table: see text]

Abstract Background Delirium is a common complication of older people in hospitals, rehabilitation and long-term facilities. Objective To assess the worldwide use of validated delirium assessment tools and the presence of delirium management protocols. Design Secondary analysis of a worldwide one-day point prevalence study on World Delirium Awareness Day, 15 March 2023. Setting Cross-sectional online survey including hospitals, rehabilitation and long-term facilities. Methods Participating clinicians reported data on delirium, the presence of protocols, delirium assessments, delirium-awareness interventions, non-pharmacological and pharmacological interventions, and ward/unit-specific barriers. Results Data from 44 countries, 1664 wards/units and 36 048 patients were analysed. Validated delirium assessments were used in 66.7% (n = 1110) of wards/units, 18.6% (n = 310) used personal judgement or no assessment, and 10% (n = 166) used other assessment methods. A delirium management protocol was reported in 66.8% (n = 1094) of wards/units. The presence of protocols for delirium management varied across continents, ranging from 21.6% (on 21/97 wards/units) in Africa to 90.4% (235/260) in Australia, similar to the use of validated delirium assessments with 29.6% (29/98) in Africa to 93.5% (116/124) in North America. Wards/units with a delirium management protocol [n = 1094/1664, 66.8%] were more likely to use a validated delirium test than those without a protocol [odds ratio 6.97 (95% confidence interval 5.289–9.185)]. The presence of a delirium protocol increased the chances for valid delirium assessment and, likely, evidence-based interventions. Conclusion Wards/units that reported the presence of delirium management protocols had a higher probability of using validated delirium assessments tools to assess for delirium.

7533 Background: Maintenance treatment (rx) with lenalidomide (R) improves overall survival (OS) in multiple myeloma (MM). We report a retrospective cohort of patients (pts) with second primary B-cell acute lymphoblastic leukemia (ALL) diagnosed after R-rx for MM. Methods: We included pts who were exposed to at least 1 yr of R for MM rx prior to ALL dx. After approval by institutional review board, data were collected by chart review at participating centers using Redcap. OS was the primary endpoint. We used BlueSky statistics v10.3.1 for analysis. Results: Analysis included 33 ALL pts diagnosed from 2014-2022 at 7 sites. 52% pts were female. Median follow up was 9.6 yrs (95%CI,7.6-11.8) from MM dx and 3.2 yrs (CI, 2.1-4.7) from ALL dx. Pt characteristics at MM dx are given in Table. Induction rx included: proteasome inhibitor (PI) +immunomodulatory drug (IMiD) (43%), PI+alkylator (24%), IMiD (18%) & others (15%). 50% pts received autologous stem cell transplantation (ASCT). Median OS from MM dx was 11.2 yrs (CI, 8.9-NR). Time from MM dx and initial R rx to ALL dx were 5.0 yrs (range, 2.4-18.5) and 4.4 yrs (2.2-10.6) respectively. Median duration of R exposure before ALL dx was 3.8 yrs (1.6-10.4). Table shows characteristics of pts at B-ALL dx and genetic classification based on karyotyping (n=30), ALL FISH (n=28), chromosomal microarray (n=5) and next-generation sequencing (n=5). 31 pts received ALL-directed rx while 1 pt was initially managed with close observation as the pt attained CR on stopping R ( Lakshman et al; ASH 2019 ). Rx was unknown in 1 pt. Initial rx included: hyper-CVAD+/- rituximab- 49%, pediatric inspired protocols-18%, reduced intensity rx for frail pts- 21% and others- 12%. Response to first line rx were: CR- 56%, CRi- 28%, induction failure- 16%. 32% pts attained measurable residual disease (MRD) negativity. 48% pts underwent SCT for ALL. 14 pts died during follow up. 3-yr OS from ALL-dx was 50% (CI, 33%-76%). 3 pts required rx for MM after ALL diagnosis (2 had allo-SCT for ALL before MM relapse). Conclusions: Most pts had standard risk MM and were exposed to R for several years prior to dx of B-ALL, characterized by high incidence of hypodiploid karyotype; IKZF1 loss and TP53 deletions/mutations were detected in a subset of pts.MRD-adapted timely discontinuation of R in standard risk MM may decrease risk of second primary ALL. [Table: see text]

Abstract Objectives Large granular lymphocytic leukemia (LGLL) represents a rare neoplasm of mature T cells or natural killer (NK) cells, with an indolent clinical course. Diagnosing LGLL can be challenging because of overlapping features with reactive processes and other mimickers. Methods By presenting 2 challenging cases, we elucidate the differentiation of LGLL from its mimics and highlight potential diagnostic pitfalls. A comprehensive review of the clinicopathologic features of LGLL was conducted. Results Large granular lymphocytic leukemia displays a diverse spectrum of clinical presentations, morphologies, flow cytometric immunophenotypes, and molecular profiles. These features are also encountered in reactive conditions, T-cell clones of uncertain significance, and NK cell clones of uncertain significance. Conclusions In light of the intricate diagnostic landscape, LGLL workup must encompass clinical, morphologic, immunophenotypic, clonal, and molecular findings. Meeting major and minor diagnostic criteria is imperative for the accurate diagnosis of LGLL.

Acute pancreatitis (AP) is among the most common hospital gastrointestinal diagnoses; understanding the mechanisms underlying the severity of AP is critical for development of new treatment options for this disease. Here, we evaluate the biological function of phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) in AP pathogenesis in 2 independent genetically engineered mouse models of AP. PFKFB3 was elevated in AP and severe AP (SAP), and KO of Pfkfb3 abrogated the severity of alcoholic SAP (FAEE-SAP). Using a combination of genetic, pharmacological, and molecular studies, we defined the interaction of PFKFB3 with inositol 1,4,5-trisphosphate receptor (IP3R) as a key event mediating this phenomenon. Further analysis demonstrated that the interaction between PFKFB3 and IP3R promotes FAEE-SAP severity by altering intracellular calcium homeostasis in acinar cells. Together, our results support a PFKFB3-driven mechanism controlling AP pathobiology and define this enzyme as a therapeutic target to ameliorate the severity of this condition.

Chimeric antigen receptor (CAR) T cell immunotherapy for the treatment of neurological autoimmune diseases is promising, but CAR T cell kinetics and immune alterations after treatment are poorly understood. Here, we performed single-cell multi-omics sequencing of paired cerebrospinal fluid (CSF) and blood samples from patients with neuromyelitis optica spectrum disorder (NMOSD) treated with anti–B cell maturation antigen (BCMA) CAR T cells. Proliferating cytotoxic-like CD8 + CAR T cell clones were identified as the main effectors in autoimmunity. Anti-BCMA CAR T cells with enhanced features of chemotaxis efficiently crossed the blood-CSF barrier, eliminated plasmablasts and plasma cells in the CSF, and suppressed neuroinflammation. The CD44-expressing early memory phenotype in infusion products was potentially associated with CAR T cell persistence in autoimmunity. Moreover, CAR T cells from patients with NMOSD displayed distinctive features of suppressed cytotoxicity compared with those from hematological malignancies. Thus, we provide mechanistic insights into CAR T cell function in patients with neurological autoimmune disease.

Abstract Deep learning may detect biologically important signals embedded in tumor morphologic features that confer distinct prognoses. Tumor morphologic features were quantified to enhance patient risk stratification within DNA mismatch repair (MMR) groups using deep learning. Using a quantitative segmentation algorithm (QuantCRC) that identifies 15 distinct morphologic features, we analyzed 402 resected stage III colon carcinomas [191 deficient (d)-MMR; 189 proficient (p)-MMR] from participants in a phase III trial of FOLFOX-based adjuvant chemotherapy. Results were validated in an independent cohort (176 d-MMR; 1,094 p-MMR). Association of morphologic features with clinicopathologic variables, MMR, KRAS, BRAFV600E, and time-to-recurrence (TTR) was determined. Multivariable Cox proportional hazards models were developed to predict TTR. Tumor morphologic features differed significantly by MMR status. Cancers with p-MMR had more immature desmoplastic stroma. Tumors with d-MMR had increased inflammatory stroma, epithelial tumor-infiltrating lymphocytes (TIL), high-grade histology, mucin, and signet ring cells. Stromal subtype did not differ by BRAFV600E or KRAS status. In p-MMR tumors, multivariable analysis identified tumor-stroma ratio (TSR) as the strongest feature associated with TTR [HRadj 2.02; 95% confidence interval (CI), 1.14–3.57; P = 0.018; 3-year recurrence: 40.2% vs. 20.4%; Q1 vs. Q2–4]. Among d-MMR tumors, extent of inflammatory stroma (continuous HRadj 0.98; 95% CI, 0.96–0.99; P = 0.028; 3-year recurrence: 13.3% vs. 33.4%, Q4 vs. Q1) and N stage were the most robust prognostically. Association of TSR with TTR was independently validated. In conclusion, QuantCRC can quantify morphologic differences within MMR groups in routine tumor sections to determine their relative contributions to patient prognosis, and may elucidate relevant pathophysiologic mechanisms driving prognosis. Significance: A deep learning algorithm can quantify tumor morphologic features that may reflect underlying mechanisms driving prognosis within MMR groups. TSR was the most robust morphologic feature associated with TTR in p-MMR colon cancers. Extent of inflammatory stroma and N stage were the strongest prognostic features in d-MMR tumors. TIL density was not independently prognostic in either MMR group.

Abstract The American Joint Committee on Cancer (AJCC) staging system for all cancer sites, including gastroenteropancreatic neuroendocrine tumors (GEP‐NETs), is meant to be dynamic, requiring periodic updates to optimize AJCC staging definitions. This entails the collaboration of experts charged with evaluating new evidence that supports changes to each staging system. GEP‐NETs are the second most prevalent neoplasm of gastrointestinal origin after colorectal cancer. Since publication of the AJCC eighth edition, the World Health Organization has updated the classification and separates grade 3 GEP‐NETs from poorly differentiated neuroendocrine carcinoma. In addition, because of major advancements in diagnostic and therapeutic technologies for GEP‐NETs, AJCC version 9 advocates against the use of serum chromogranin A for the diagnosis and monitoring of GEP‐NETs. Furthermore, AJCC version 9 recognizes the increasing role of endoscopy and endoscopic resection in the diagnosis and management of NETs, particularly in the stomach, duodenum, and colorectum. Finally, T1NXM0 has been added to stage I in these disease sites as well as in the appendix.