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Abstract Background: Systemic mastocytosis (SM) comprises a spectrum of subtypes characterized by neoplastic mast cell (MC) infiltration of tissues and release of MC mediators. Non-advanced SM (NonAdvSM), including indolent SM (ISM), smoldering SM (SSM), and bone marrow mastocytosis (BMM) subtypes, is the most prevalent form of SM. NonAdvSM can be associated with debilitating symptomology which can significantly impair quality of life. The gain-of-function somatic KIT c.2447 C>T (p.D816V) mutation is found in up to 95% of patients with SM. Bezuclastinib (CGT9486) is an oral, potent, and selective type 1 tyrosine kinase inhibitor with activity against KIT D816V. Results from Summit (NCT05186753) Part 1 informed the recommended phase 2 dose (100 mg QD bezuclastinib) for Part 2. We report topline results from the 24-week assessment of Summit Part 2. Methods: Summit is a multi-center, randomized, double-blind, placebo (PBO)-controlled Phase 2 trial of bezuclastinib in patients with NonAdvSM who had inadequate symptom control despite best supportive care (BSC) medications. The primary endpoint was 24-week mean change from baseline in Mastocytosis Symptom Severity Daily Diary (MS2D2) total symptom score (TSS) (range 0–110), which is a fit-for-purpose patient-reported outcome measure of NonAdvSM symptom severity. Key secondary endpoints included the proportion of patients with ≥50% reduction in serum tryptase, KIT p.D816V variant allele frequency (VAF), bone marrow (BM) MC burden, and MS2D2 TSS, ≥30% TSS reduction. Patients were randomized 2:1 to receive 100mg QD bezuclastinib + BSC or PBO + BSC. Results: As of May 22, 2025, 179 patients were enrolled in Part 2: 119 were randomized to receive bezuclastinib and 60 to placebo. Patients enrolled were representative of the NonAdvSM population with moderate to severe symptoms. Median age (range) was 51 (23-78) years; 65.9% female; mean (SD) baseline MS2D2 TSS 55.6 (19.8); 82% of patients had ISM, 11% had BMM, and 7% had smoldering SSM. At baseline, median (range) KIT p.D816V VAF in whole blood, BM MC burden, and serum tryptase was 0.25% (0-34%), 10% (1-75%), and 40 (6-692) ng/mL, respectively. Bezuclastinib demonstrated statistically significant superiority to placebo on all primary and key secondary endpoints. At Week 24, bezuclastinib led to significantly greater symptom improvement vs placebo (LS mean [95% CI] MS2D2 TSS change: –24.3 [–27.6 to –21.1] vs –15.4 [–19.6 to –11.2]; placebo-adjusted difference: –8.9 points; P=0.0002). A ≥50% reduction in serum tryptase was achieved in 87.4% of bezuclastinib-treated patients vs 0% on placebo (P<0.0001). Significantly more patients receiving bezuclastinib achieved ≥50% reductions in KIT D816V VAF, serum tryptase, BM MCs (P<0.0001), MS2D2 TSS (P=0.01), and ≥30% reduction in MS2D2 TSS (P=0.0004). Most treatment-emergent adverse events (TEAEs) were low grade (gr; 70% Gr 1) and reversible. The most common TEAEs (≥10%) in any treatment group and occurring in greater frequency in the bezuclastinib arm were hair color changes (69.5% vs 5.0%), altered taste (23.7% vs 0%), nausea (22.0% vs 13.3%), increased ALT/AST (22.0% vs 6.6%), headache (17.8% vs 11.7%), alopecia (11.9% vs 3.3%), and increased ALP (10.2% vs 3.3%). TEAEs (≥10%) that occurred more often in the placebo group were diarrhea (13% vs 18%), dizziness (10% vs 12%), fatigue (7% vs 12%), and arthralgia (6% vs 15%). ALT/AST elevations ≥Gr 3 were experienced by 5.9% of patients. The only hepatic adverse events (AEs) reported were transient lab abnormalities; none required hospitalization. Treatment-related AEs requiring dose reductions occurred in 11% of patients receiving bezuclastinib. All discontinuations (5.9%) due to treatment-related AEs were due to transaminase elevations; all fully resolved. Conclusions: At 24-weeks, bezuclastinib 100 mg QD demonstrated statistically and clinically significant improvements in symptom burden and biomarkers of disease vs placebo in patients with NonAdvSM. The treatment was generally well-tolerated and effective across a population that is representative of the real-world NonAdvSM population, including SSM. These results support the use of bezuclastinib to reduce SM burden and symptoms in pts with NonAdvSM, and a potentially disease-modifying impact.

Abstract Background Chimeric antigen receptor T-cell (CAR-T) and bispecific antibody (BsAb) therapies are both effective for patients with relapsed/refractory (R/R) follicular lymphoma (FL), but differ in treatment schedules and associated “time toxicity,” or contact days spent physically interacting with the healthcare system. While contact days can be estimated from clinical trials, real-world data provides a more nuanced depiction of treatment-related time burden, which may guide treatment decision-making. The comparative time toxicity of CAR-T vs BsAb in R/R FL is not defined. Methods We conducted a multicenter retrospective study of adults with R/R grade 1-3A FL who received standard-of-care CAR-T (axi-cel, tisa-cel, liso-cel) or BsAb (mosunetuzumab, epcoritamab) in the third-line or later setting before Jan 1, 2025. Time toxicity was defined as outpatient or inpatient days with physical health care system contact, counting multiple visits on the same day as only one day. All days after treatment initiation were counted, regardless of disease progression, therapy completion, or relation to FL therapy. Median contact days over 1-year time horizon were compared, stratified by CAR-T vs BsAb, prior lines of therapy (LOT, 2 vs 3+), and time intervals (0-1, 1-3, 3-6, 6-9, and 9-12 months). Progression-free survival (PFS) and overall survival (OS) were calculated from day of CAR-T infusion or day 1, cycle 1 for BsAb. Cox regression and propensity matching (by age, ECOG, refractory to prior LOT, POD24) were used to assess predictors and survival associations with contact days. Results Among 209 patients from 15 U.S. academic centers, median age was 64, 37% were female, 61% received CAR-T (80% axi-cel, 7% liso-cel, 13% tisa-cel) and 39% BsAb (93% mosun, 7% epcor). Most had Grade 1-2 FL (72%), advanced stage (84%), and extranodal disease (51%). Median prior LOT was 3 (range 2-15), 41% were refractory to prior LOT, and 52% had POD24. Median number of BsAb doses was 10 (range 1-36). Patients receiving BsAb were significantly older (p<.01) and had higher CIRS comorbidity scores (p<.02) in both 2 and 3+ prior LOT cohorts, and had higher ECOG scores (p=.01) and were less likely to be refractory to prior LOT (p=.029) in 3+ LOT cohort. There were no differences in POD24 rates between CAR-T and BsAb. Median PFS for the entire cohort was 3.6 yrs; median OS was not reached. In the 2 prior LOT cohort (N=75), 60% received CAR-T and 40% BsAb. With median follow-up of 1.5 years, median PFS was not reached for CAR-T and 1.6 yrs for BsAb (p<.0001). In the 3+ prior LOT cohort (N=134), 62% received CAR-T and 38% BsAb. With median follow-up of 2 yrs, median PFS was 3.6 yrs for CAR-T and 1.6 yrs for BsAb (p=.0044). In propensity matched analysis, PFS was shorter for BsAb in both 2 LOT (HR 9.0, 95% CI 1.14-71.04, p=.037) and 3+ LOT (HR 3.25, 95% CI 1.06-9.97, p=.039) cohorts as compared to CAR-T. There were no significant differences in OS between CAR-T and BsAb. Median contact days were significantly higher for CAR-T vs BsAb in the 0-1 month interval: 19 vs 8 days in 2 LOT (p<.0001) and 18 vs 7 days in 3+ LOT (p<.0001) cohorts. There were no differences in contact days between CAR-T vs BsAb in subsequent time intervals. Over 1 year, CAR-T had significantly more time toxicity than BsAb: median 51 vs 36 contact days in 2 LOT (p<.0001) and 64 vs 38 days in 3L+ LOT (p<.0001) cohorts; these remained significant in the matched analysis. B symptoms (p=.04) and Grade ≥3 cytopenias (p=.007) were associated with higher contact days in 3+ LOT cohort in univariable analysis. Higher contact days were associated with inferior PFS (HR 1.01, 95% CI 1.00-1.02, p=.032) and OS (HR 1.01, 95% CI 1.00-1.02, p=.038) in 3+ LOT cohort regardless of treatment type. Discussion In this large real-world cohort of patients with R/R FL, CAR-T therapy resulted in better PFS but more time toxicity over the first year as compared to BsAb therapy. Excess time toxicity from CAR-T was driven by more contact days in the first month of treatment. This study provides benchmark data for counseling patients about expected time burden of CAR-T (51-64 days) and BsAb (36-38 days) over the first year of these therapies. Further, with superior PFS of CAR-T in this study and minimal impact of time toxicity on survival outcomes, these data can be used to better support shared decision-making in R/R FL by addressing patient preferences regarding both contact days as well as duration of disease control.

Abstract SWOG 1318 evaluated the feasibility of combining the tyrosine kinase inhibitor (TKI) dasatinib with prednisone and blinatumomab in older patients (pts) with Philadelphia chromosome positive (Ph+) B-acute lymphoblastic leukemia (ALL). Here, we present longer follow up (median follow up 5.6 years) with outcomes, predictors of response, and translational medicine studies. Methods: This trial was activated through the NCTN in January 2014 and closed to accrual in April 2021. Pt eligibility included: age > 65 years, Ph+ ALL, no evidence of central nervous system (CNS) disease, and adequate organ function. Treatment has been previously described (Blood Adv 2023; 7(7): 1279-85). Statistics: Categorical and quantitative endpoints comparisons used Fisher's exact and Wilcoxon tests. Survival endpoints used the Kaplan-Meier method and Cox regression models and were landmarked for post-baseline events as needed (i.e., number of cycles). Translational medicine studies: Single cell ATAC seq (10x genomics) was performed on 9 archived cryopreserved diagnostic samples from patients with > 500,000 cells. All samples successfully completed library preparation, sequencing, and demonstrated adequate blast clusters for analysis. Briefly, cryopreserved cells were thawed, and transposases were introduced into nuclei in single cell suspension and used to generate GEM beads. ATAC seq libraries were prepared per manufacture instructions. Libraries were then sequenced on a 25B flow cell on Novaseq X plus (Illumina). The data were analyzed with cloupe (version 9.0.0). Results: Twenty-four eligible patients were enrolled. The median age was 73 years (range 65-87). All pts had newly diagnosed Ph+ ALL. Seventy-nine percent of pts had additional cytogenetic abnormalities. Twenty-two pts (92%) achieved a complete remission (CR) during dasatinib and prednisone induction therapy. Most sites also monitored patient's blood or bone marrow with real-time quantitative PCR to quantify the BCR-ABL1 transcript for molecular response. Of 19 patients analyzed 17 (89%) were in a major or complete molecular remission at some point after treatment, with at least 12 of these patients achieving complete molecular remission. Three patients remain on maintenance. The median follow up for patients who are alive is 5.6 years (range 4.4-8.3). Five- year OS and DFS estimates are 63% (95% CI: 40-78%) and 64% (95% CI: 40-80%). Two patients relapsed in the CNS. One pt proceeded to allogeneic hematopoietic stem cell transplant (HSCT) and 1 to autologous HSCT. Increased age was associated with a decreased chance of achieving CR as best response (median age in responder group 73.2 years [range 65-82.9]; median age in non-responder group 85.5 [range 83.8-87.3]; p=0.02). Patients with extramedullary disease had shorter DFS (HR 0.22, 95% CI 0.04-1.15, p=0.07). Increased number of cycles of blinatumomab received was associated with a trend towards improved OS (HR 0.66, 95% CI 0.41-1.08, p=0.10). Translational medicine studies for chromatin accessibility in the blast clusters demonstrated improved OS in patients with homogeneous blast clusters (HR 0.42, 95% CI 0.06-3.04, p=0.39), high DUX4 differential accessibility (HR 0.26, 95% CI 0.03-2.55, p=0.25), and ATAC seq data corresponding to decreased chromatin accessibility in HOXA2 (HR 0.09, 95% CI 0.01-1.05. p=0.06). Conclusions: Despite an elderly population, this trial demonstrated impressive outcomes with longer follow-up for patients with Ph+ ALL. The number of cycles of blinatumomab and the presence of extramedullary disease may be important factors in outcome. Translational studies suggest additional markers may be predictors of overall survival, and these will need to be studied on larger scale studies. Decreased chromatin accessibility to HOXA2 was associated with a trend towards improved OS. Additional translational medicine will also be presented at the meeting.

Abstract Consumption of a Western diet and high body mass index (BMI) are risk factors for progression from premalignant phenotypes to multiple myeloma, a hematologic cancer. In the NUTRIVENTION trial (NCT04920084), we administered a high-fiber, plant-based diet (HFPBD; meals for 12 weeks, coaching for 24 weeks) to 23 participants with myeloma precursor states and elevated BMI. The intervention was feasible and improved quality of life and modifiable risk factors: metabolic (BMI, insulin resistance), microbiome (diversity, composition), and immune (inflammation, monocyte subsets). Disease progression trajectory improved (n = 2) or was stable. Findings were translated to Vk*MYC mice modeling the myeloma precursor state, in which a high-fiber diet (HFD) delayed disease progression through improved metabolism and microbiome composition, leading to increased short-chain fatty acid production that reinvigorated antitumor immunity and inhibited tumor growth. These effects from fiber consumption were independent of calorie restriction and weight loss. A HFD is a low-risk intervention that may delay progression to myeloma. Significance: A HFPBD in participants with precursor plasma cell disorders and an elevated BMI improved metabolic, microbiome, and immune biomarkers of disease. In a subset, it may delay progression to myeloma. In mouse models, a HFD delayed progression to myeloma independent of calorie restriction. See related commentary by Fairfield and Reagan, p. 623

Abstract Follicular lymphoma (FL) is the most common indolent non-Hodgkin lymphoma. Although patients with FL have high response rates to therapy, most develop increasingly resistant disease. In addition, transformation into an aggressive lymphoma is associated with unfavorable outcomes. Many novel agents are under investigation, and early clinical data are encouraging. Aligning treatment with the underlying tumor biology and sequencing of therapies remain key clinical challenges. At the Lymphoma Research Foundation’s biannual 2024 Follicular Lymphoma Scientific Workshop, experts convened to discuss the role of chemotherapy in the context of new therapies, the impact of early progression on treatment sequencing, novel end points in clinical trials, disease biology and the tumor microenvironment, and new treatments on the horizon. This report focuses on updates in FL biology, first-line treatment, the role of progression of disease in 24 months, clinical trial design, and redefining cure in FL.

Abstract Background Patients with Crohn disease (CD) face an elevated risk of developing small bowel adenocarcinoma (SBA), a malignancy characterized by late-stage diagnosis and poor prognosis. In this study we aimed to characterize surgical management and oncologic outcomes for CD-associated SBA. Methods A retrospective review was conducted across 3 tertiary IBD centers, analyzing 99 patients with CD who underwent surgery for SBA between 1992 and 2025. Data included patient demographics, CD history, surgical details, and oncologic outcomes. Results The median time from CD diagnosis to SBA was 25 years. The SBA diagnosis was incidental in 74.8% of cases, discovered during surgery for other complications. Tumors were predominantly located in the ileum (80.8%) and showed aggressive features: 56.6% were poorly differentiated (grade 3), and 85.9% were pathologically advanced (T3/T4 on TNM staging). Nodal involvement was present in 45.5% of patients, and 18.2% had distant metastases at diagnosis. A complete (R0) resection was achieved in 90.9% of surgeries, with a 30-day morbidity rate of 26.3%. After a median follow-up of 36 months, the distant recurrence rate was 28.3%, and overall mortality was 27.3% (18.2% cancer related). Conclusion In patients with long-standing CD, SBA is typically an incidental diagnosis made at an advanced stage. While high rates of complete surgical resection are possible, the prognosis remains guarded due to aggressive tumor biology and high recurrence rates. These findings highlight a critical need for improved risk stratification to guide surveillance and for the development of evidence-based adjuvant treatment strategies.

PURPOSE Although most patients with follicular lymphoma (FL) can expect an indolent course, progressive lymphoma remains the primary cause of death during the first decade after diagnosis. Progression of disease within 24 months (POD24) of starting first-line (1L) immunochemotherapy defines a high-risk population with poor survival, but better risk stratification at diagnosis is needed. METHODS The FLIPI24 model was developed and internally validated to predict 24-month event rates using individual data from 4,485 patients treated with 1L immunochemotherapy from 10 observational cohorts of FL. Overall and cause-specific survival was further evaluated in FLIPI24 risk groups. External validation in the 1L immunochemotherapy setting was performed using the prospective observational Lymphoma Epidemiology of Outcomes (LEO) cohort (N = 565) and three randomized phase III trials (N = 3,192); extension to all patients with FL (any 1L therapy) was performed in the LEO cohort (N = 1,445) and its Molecular Epidemiology Resource subcohort (N = 1,074). RESULTS The FLIPI24 model uses age and four blood-based variables (hemoglobin, lactate dehydrogenase, beta-2 microglobulin, and WBC count). FLIPI24 showed consistent performance across validation and extension data sets, which was superior to existing prognostic tools. Across the four external immunochemotherapy validation data sets, patients with high-risk FLIPI24 (23%-32% of patients) had significantly higher 24-month event rates (22%-35%) and inferior 5-year overall survival (77%-83%) compared with patients with low-risk FLIPI24 (29%-31% of patients, 24-month event rates: 10%-12%; 5-year OS: 96%-97%). Results were consistent when evaluating lymphoma-related death and when extended to all patients with FL. CONCLUSION The FLIPI24 model robustly stratifies, at diagnosis, patients with FL at increased risk of lymphoma-related death versus patients with very low lymphoma-related mortality during the first decade after diagnosis. FLIPI24 can be used to enrich future clinical trial designs in newly diagnosed FL.

Introduction Software packages for quantification of CT perfusion parameters allow quick visualization of perfusion deficits to support clinical decision making in acute ischemic stroke (AIS). Several packages are now commercially available for automated quantification of ischemic core, penumbra volumes, and mismatch ratios to indicate eligibility for reperfusion therapies. This study explored the agreement between two software packages, Brainomix 360 e‐CTP and Rapid CTP, in prospective, real‐world use. Methods Consecutive patients scanned for suspected stroke at three comprehensive stroke centers over 90 days from May to July 2024 were included in the study. Eligibility for the current analysis was limited to discharge diagnosis of AIS and CTP imaging processed by both Brainomix and Rapid software. Software processing was conducted in real time after image acquisition. The presence of large vessel occlusion (LVO) was determined from review of electronic medical records. CTP core (CBF<30%) and penumbra (Tmax>6s) volumes from Brainomix and Rapid were recorded for each case. Mismatch ratios were calculated (penumbra÷core volume); positive mismatch was defined according to DEFUSE‐3 criteria (core<70ml, penumbra>15ml, mismatch ratio > 1.8). The correlations and linear regressions between Brainomix and Rapid were computed for core, penumbra and mismatch ratios, and their concordance for mismatch positivity was assessed. Results 137 patients were scanned and received a final diagnosis of AIS. Of these, only 38 had imaging processed by both Brainomix and Rapid. Median age was 69 years (interquartile range: 57‐77.5y); 16 (42%) were female; 13 (34%) had LVO. Linear models between Brainomix and Rapid's outputs for CBF and Tmax volumes are shown in Figure 1a and 1b. The correlation between software outputs for CBF volume was r=0.70 (p<.001), and for Tmax volume was r=0.72 (p<.001). Mismatch ratios were calculated for the 13 cases with LVO (Figure 1c). The linear model between mismatch ratios was not significant, with four Rapid outputs showing infinite mismatch ratios (due to having CBF volumes of 0ml). Concordance between software for mismatch positivity was good; 8/13 cases showed mismatch on both softwares; 1 case showed mismatch on Brainomix only; 1 for Rapid only; and 3 cases showed mismatch on neither software. Conclusion This prospective study, despite limited sample size (N=38), showed good correlations between Brainomix 360 e‐CTP and Rapid CTP for calculation of both core and penumbra volumes. Although mismatch ratios showed less agreement, the categorization of mismatch positivity showed good concordance between software platforms. image

Purpose White matter hyperintensity (WMH) is associated with heterogeneous pathologies. In neurodegeneration, the prevailing hypothesis is that WMH primarily reflects vascular pathology, exerting an additive effect in AD. Alternatively, a subset of WMH may arise secondary to AD‐related pathophysiology. APOE4 genotype, the greatest genetic risk factor for late‐onset AD, impacts the blood‐brain barrier and WMH burden. Herein, we investigate the association between regional WMH burden and APOE4 allelic dosage in cognitively normal individuals. Methods We used deep learning to automatically segment WMH from T2‐FLAIR MRI from 154 cognitively intact individuals older than 50. We mapped WMH to 4 specific brain regions (lobar, periventricular, basal ganglia and infratentorial, further parcellated into sub‐regions, Table 1) using atlas‐based registration and FastSurfer. WMH volumes were adjusted for total intracranial volume and normalized using log transformation. The APOE4 groups were compared for WMH burden using linear regression, controlling for age and vascular risk factors (hypertension, diabetes, hypercholesterolemia, cigarette smoking). For brain regions where more than 20% of participants had no WMH, a two‐part hurdle model was applied. Results We included 13 APOE4 homozygotes, 50 heterozygotes (ε4/ ε3) and 91 non‐carriers. Compared to non‐carriers, APOEε4 homozygotes exhibited significantly greater WMH burden in the whole brain, periventricular (posterior) and lobar regions (Figure 1a). Homozygotes exhibited a significantly greater WMH burden in the whole brain and posterior periventricular region, when compared to heterozygotes (Figure 1b). No significant whole‐brain or region‐specific differences were observed between heterozygotes and non‐carriers (Figure 1c). Conclusion In cognitively intact individuals at risk for AD, APOE4 homozygosity is associated with significantly greater WMH burden, particularly in the posterior periventricular space, after controlling for age and vascular risk factors. The relationship between regional‐specific WMH burden and neurodegeneration warrants further investigation. image image