Citations

1633 Background: CAR-T cell therapy has transformed outcomes of hematologic malignancies and is poised to expand into solid malignancies. However, broader use of CAR-T remains constrained by the need for timely cytokine release syndrome (CRS) detection. Current episodic monitoring may miss early physiologic changes. Wearable digital health technologies (DHTs), offering continuous monitoring and real-time alerts, could enable earlier CRS detection, further support outpatient delivery, and expand access to CAR-T and potentially other immunotherapies associated with CRS. Methods: This single-center observational study (NCT05018208) enrolled patients receiving FDA-approved CAR-T products in the outpatient setting at Mayo Clinic, Rochester MN. Management of post-CAR-T complications (e.g. CRS) followed the institution’s standard of care. Patients were monitored from day -5 to day +30 post infusion with intermittent remote patient monitoring (SoC) and an arm-worn wearable device for continuous monitoring (DHT). Patients were included in this analysis if DHT data were available for ≥ 5h of data/day or ≥ 2h of data/night on ≥2 days or nights for baseline and ≥1 day or night within 72h prior to CRS, or at least 2h within 4h of CRS onset, or if DHT was available for ≥7 days/nights post infusion with no CRS event. CRS detection time by DHT was defined as the onset of pyrexia or threshold-based deviation from an individual’s baseline pulse distributions. Results: 32 patients were included in this report (median age 64 years, gender 12 F/20 M, diagnoses 18 MM/14 NHL). 25 patients experienced a CRS event, with maximum CRS grades ranging from 1-3 (16 G1, 8 G2, 1 G3). 24/25 patients with CRS required tocilizumab/steroid. Median CRS onset time was 3.4 days (range 0.4-18.4). 12/32 patients had sufficient DHT data (7 CRS, 5 no CRS) for analysis. 5 patients with CRS had a DHT detection time in advance of the SoC by a median of 13h (range 2.8 - 69.2). The DHT prediction of CRS by baseline HR change was earlier than the first episodic fever by a median of 14.5h (range 13-77.5). The remaining 2/7 patients who did not have CRS detected by the DHT had missing DHT data for more than 45h before a treated CRS event. DHT detected CRS in 2/5 patients without CRS according to SoC. One patient had fever caught with intermittent monitoring. The other was treated for neutropenia fever with suspicion of CRS and/or infection. Conclusions: These results offer evidence that continuous DHT can identify CRS events earlier than intermittent monitoring (SoC). Despite limitations related to compliance with wearable device use and data missingness, and variability in clinical management of CRS, we highlight the usability of DHT and its potential for future studies with optimized strategies to address these limitations. Clinical trial information: NCT05018208 .

1503 Background: CAR T-cell therapy has revolutionized treatment outcomes in hematological malignancies, but has traditionally required inpatient post-infusion monitoring, which is associated with significant cost and time toxicity. Outpatient CAR T infusion and monitoring has been the standard approach at Mayo Clinic site in Rochester, MN, with demonstrated feasibility and safety (Bansal et al., ASCO 2023). We present data comparing healthcare utilization between CAR T recipients who underwent outpatient remote monitoring and those with traditional inpatient monitoring. Methods: Electronic medical records were retrospectively analyzed for 293 patients who received CAR T-cell therapy for a hematological malignancy at any of the 3 Mayo Clinic sites (MN, AZ, FL) between 2020 and 2024 . Healthcare utilization was compared between patients who received outpatient CAR T with remote patient monitoring in Rochester, MN (N = 125) and those who received inpatient CAR T in the Arizona (n = 90) and Florida (n = 78) sites. Per protocol, patients in the inpatient group underwent mandatory inpatient monitoring for 7 days, with extension per provider discretion. Data was analyzed through Chi-Square and Wilcoxon tests. P values < 0.05 were considered statistically significant. Results: There was no significant difference in baseline sex, age, ethnicity, LDH, platelets, or neutrophils among the 293 patients. Diagnoses included lymphoma (n = 175), multiple myeloma (n = 106), and B-ALL (n = 12). The most common CAR T-cell products used were axicabtagene ciloleucel (n = 138) idecabtagene vicleucel (n = 56), and ciltacabtagene autoleucel (n = 50). Median hospital days were lower in the outpatient group vs the inpatient group at 30 days (4.4 vs 13.3, P < 0.001) and 90 days (4.6 vs 13.6, P < 0.001). ICU admission occurred in 1 outpatient patient ( < 1%) vs 18 inpatient patients (11%) in the first 30 days (P < 0.001). In the first 30 days, 22% of patients in the outpatient group did not require hospitalization, while 56%, 15%, and 6% required 1, 2, and 3 hospitalizations, respectively. Similarly, only 11 (8.8%) patients in the outpatient group had ≥1 ED visit in the first 30 days compared with 32 (20%) pts in the inpatient group (P = 0.009). At 30 days, there was no difference in patient portal use, with 58% of patients using the portal at least once and a median of 1 message in both groups. Within the first 30 days, 53% and 2% of patients in the outpatient group required 1 and 2 outpatient visits, respectively, vs 29% and 2% in the inpatient group (P < 0.001). There was no difference in 30-day mortality (1.6% outpatient vs 2.4% in inpatient) between the 2 groups (P = 1.00) Conclusions: Outpatient CAR T-cell therapy monitoring was associated with significantly fewer hospital days without increased ED visits, ICU stays, portal use, or 30-day mortality. This demonstrates lower healthcare utilization for outpatient CAR-T therapy.

Abstract Rationale Non-selective beta-blockers (BB) are the standard of care for variceal prophylaxis in patients with cirrhosis. It is unclear whether BB negatively affect exercise capacity in patients with portopulmonary hypertension (POPH) or hepatopulmonary syndrome (HPS). We hypothesize that BB use is associated with shorter six-minute walk distance (6MWD) in HPS and POPH than in patients without pulmonary vascular complications of liver disease. Methods The Pulmonary Vascular Complications of Liver Disease 2 (PVCLD2) Study enrolled patients evaluated for liver transplantation or pulmonary hypertension at eight U.S. centers (2013-2017). We conducted a retrospective analysis of 333 patients with HPS, POPH, and portal hypertension without lung complications to evaluate whether disease state modified the association of BB on 6MWD. Multivariable linear regression adjusted for a priori covariates including age, sex, body mass index (BMI), MELD-Na, and WHO functional class. An interaction term between disease category and BB use was included. Results We included 85 patients with HPS, 48 with POPH, and 200 patients with liver disease. Compared to liver disease controls, those with HPS were younger, had higher MELD-Na scores, and more often had worse WHO functional class. POPH patients were similar to controls in age and liver disease severity but had higher WHO functional class. Sex, BMI, and left ventricular ejection fraction did not differ significantly between groups. Higher age, BMI, MELD-Na, and WHO functional class were all significantly associated with lower 6MWD while male sex was associated with higher 6MWD. Adjusting for age, sex, BMI, MELD-Na score, and WHO functional class, there was a significant interaction between BB use and disease category (p = 0.024). Patients with HPS had a 53.4 m longer 6MWD with BB use (95% CI 4.21- 102.5, p = 0.03 for interaction) compared to liver disease controls, whereas patients with POPH had a 72.4 m longer 6MWD (95% CI 7.60- 137.2, p = 0.03 for interaction) compared to liver disease controls. Conclusion The association of BB with 6MWD in advanced liver disease appears to be modified by whether a person has a pulmonary vascular complication including HPS or POPH. The mechanisms for these differences and their clinical implications require further study. This abstract is funded by: NIH T32 Grant

OBJECTIVES We aimed to characterize the frequency of major complications of acute COVID-19 and multisystem inflammatory syndrome in children (MIS-C) and adolescents present at 6 months after initial presentation. METHODS The Pediatric Research Immune Network on SARS-CoV-2 and MIS-C (PRISM) study was a prospective cohort at 20 US pediatric academic medical centers. Individuals aged younger than 21 years meeting any of the following were enrolled: SARS-CoV-2 detection within 7 days, Centers for Disease Control and Prevention (CDC) MIS-C criteria, or CDC MIS-C criteria except having involvement of 1 organ system. The study was designed to assess the proportion of children with major complications (cardiovascular, pulmonary, gastrointestinal/hepatic, renal, and/or neurologic) 6 months after presentation. RESULTS Data were analyzed on 229 hospitalized participants: 59 with COVID-19 (mean age 10.4 years; SD, 5.5) and 170 with MIS-C (mean age 10.1 years; SD, 4.8). Overall, 42.8% were female, making up 55.9% and 38.2% of the COVID-19 and MIS-C groups, respectively. Overall, the frequencies of major complications at 6 months after initial presentation were: 16/195 (8.2%) cardiovascular, 11/154 (7.1%) pulmonary, 11/154 (7.1%) gastrointestinal/hepatic, 3/152 (2.0%) renal, and 3/189 (1.6%) neurologic. Organ system complications did not differ significantly between the COVID-19 and MIS-C groups. Six of 14 (42.9%) COVID-19 and 21/26 (80.7%) MIS-C participants with at least 1 six-month complication had no underlying medical condition that may have been associated with their complication(s). CONCLUSIONS Major complications were infrequent but observed in children without underlying medical conditions, underscoring the importance of prospective follow-up to optimize management and elucidate the complications associated with severe SARS-CoV-2 infection in children.

Abstract Transcriptional condensates (TCs) are dynamic, membrane-less assemblies of proteins and nucleic acids that form at specific genomic loci to control gene expression. The primary drivers of TC formation and function are long stretches of polypeptide chains that lack well-defined tertiary structure, known as the intrinsically disordered regions (IDRs) of Transcription Factors (TFs). However, the role of well-structured domains such as the DNA-binding domain (DBD) in condensate formation and downstream regulation remains poorly understood. Here, we investigated whether the DBD of the Progesterone Receptor (PR), a model TF regulated by hormone binding, contributes to the formation of PR TCs. By combining Single Particle Tracking (SPT) with deep-learning-based single-trajectory analysis, we demonstrated that both the IDR and the DBD are required for the formation of PR condensates. Furthermore, transcriptomic analysis showed that mutations of either of the two domains result in the expression of a distinct set of genes, with functional assays corroborating these findings and linking domain-specific transcription to differential effects on cell proliferation and migration. Together, our results show that domains beyond IDRs also play a role in TC formation and function and uncover domain-specific regulation of transcriptional and oncogenic programs.

Abstract Solitary bone plasmacytoma (SBP) and SBP with minimal marrow involvement (SBPmm) are treated similarly with definitive radiation therapy (RT) followed by observation. However, differences in the natural disease course after RT between the two, are not well described. We performed a multicenter study assessing outcomes after RT in 141 patients with SBP and 102 with SBPmm diagnosed between January 2010 and December 2024. About 92% of patients with SBPmm progressed to multiple myeloma (MM) vs 76% of those with SBP (P = .01). Among patients with SBP, 21% progressed with a second solitary bone lesion vs 4% with SBPmm (P&lt; .01). Patients with longer time to progression (TTP) after initial RT could achieve durable responses with RT to a second solitary plasmacytoma in the absence of other myeloma-defining events (MDE). Multifocal lytic bone lesions were the most common MDE, occurring in 89% and 81% of patients with SBPmm and SBP, respectively. Patients with SBPmm had a median TTP of 15 months (95% confidence interval [CI], 14-21) compared to 43 months (95% CI, 34-55) for those with SBP (P&lt; .0001); 67% with SBPmm progressed within 2 years of diagnosis. Del(17p) and 1q+ (gain or amplification) were associated with shorter TTP to MM in SBPmm, with 2-year progression rates of 100% and 82%, respectively. We report significant differences in risk and modes of progression between SBP and SBPmm. Patients with SBPmm are at particularly high risk for early progression to MM, with most developing bone disease as the MDE. These findings support prospective studies incorporating frontline systemic therapy for SBPmm.

Abstract Gastrointestinal (GI) involvement is a clinically relevant but undercharacterized manifestation of systemic light chain amyloidosis (AL). We aimed to define the clinical spectrum, histologic patterns, and outcomes of symptomatic GI involvement in AL. We retrospectively analyzed 4396 patients with AL from 2010 to 2024, of whom 521 (11.9%) had provider-attributed symptomatic GI involvement; 66% had biopsy-proven GI AL. Symptoms most commonly included early satiety (61%), bowel irregularities (58%), nausea (35%), abdominal pain (28%), and dysphagia (23%). Autonomic neuropathy was frequent (43% clinician attributed; 23% via autonomic reflex testing) and contributed to dysmotility-related symptoms, often without GI biopsy positivity. Among 747 GI biopsies, mucosal infiltration predominated (71%) and was associated with bleeding (22% vs 9%), cachexia, and inferior survival, whereas vascular involvement was associated with lower bleeding risk. Combined involvement of mucosa, submucosa, and vessels conferred the worst prognosis (median overall survival [mOS], 2.4 vs 5.1 vs 7.8 years for 3 vs 2 vs 1 layer); mOS was 6.8 years and was primarily driven by cardiac stage and hematologic response (very good partial response [VGPR] or better: hazard ratio, 0.20; 95% CI 0.13-0.32), with more favorable outcomes in patients with isolated GI involvement. Cachexia and persistent diarrhea were the main drivers of morbidity, need for nutritional support, and GI-related mortality (odds ratio, 2.7 for the combined end point). GI bleeding rarely recurred after achieving VGPR or better. Overall, mucosal involvement, cachexia, and dysmotility define clinically meaningful GI AL and support systematic assessment of autonomic dysfunction as well as evaluation of the need for nutritional support as a GI-specific end point for AL trials.

Abstract Systemic light chain amyloidosis (AL) arises from monoclonal immunoglobulin light chains, but determinants of progression from precursor states remain poorly defined. In a cross-sectional cohort comprising 1950 systemic AL patients diagnosed 2010-2024, 258 (13.2%) patients with a previously diagnosed plasma cell disorder (PCD) were compared to patients with no prior PCD diagnosis. Patients with monoclonal gammopathy of undetermined signficance (MGUS) and smoldering multiple myeloma (SMM) in the former group had lower difference between involved and uninvolved FLCs (dFLC), higher M-protein, and lower rates of t(11;14) at AL diagnosis. Patients developing AL from SMM had a shorter time to AL (median 34.2 versus 61.3 months) and higher dFLC (median 28.9 versus 11.0 mg/dl) compared to those from MGUS. Patients developing AL after known multiple myeloma (MM) or lymphoplasmacytic lymphoma (LPL) commonly lacked deep hematologic response before AL (≤ very good partial response in 78% of MM, 100% of LPL patients). We additionally studied longitudinally followed cohorts of 3,966 MGUS and 426 (SMM) patients with longitudinal FLC measurements and matched follow-up, in which 1.8% of MGUS and 7.2% of SMM patients developed AL. Those patients who developed AL showed markedly higher dFLC at MGUS/SMM diagnosis and more frequent λ restriction and rates of t(11;14). Higher dFLC was associated with progressively earlier AL development; a 10% cumulative risk occurred at 20 months for patients with a dFLC >80 mg/dL but was not reached if dFLC <10 mg/dL at an estimated median follow-up of 86 months. In multivariable analysis, dFLC >6.4 mg/dL (HR 11.3) and λ isotype (HR 3.6) independently predicted AL, whereas heavy chain secretion was associated with lower risk (HR 0.2 for IgG). These findings indicate that AL risk is primarily driven by cumulative light chain exposure, refining our knowledge of AL pathophysiology and providing guidance for follow-up of patients with elevated dFLC.

Abstract Background X‐ray Induced Acoustic Computed Tomography (XACT) is an emerging imaging technique that provides 3D volumetric images from a single projection by detecting X‐ray‐induced acoustic (XA) waves with ultrasound (US) transducers. Unlike MRI or CT, XACT enables real‐time 3D imaging without long acquisition times, 2D limitations, or motion artifacts from mechanical rotation. Furthermore, when integrated with conventional pulse‐echo US through time‐sequenced operation, XACT provides complementary soft‐tissue contrast, establishing it as a promising platform for dynamic interventional radiology (IR) guidance. Purpose This study aims to evaluate the feasibility of XACT as a novel imaging tool for IR, specifically for guiding needle placement and monitoring contrast agent dynamics. Methods We developed a 3D XACT imaging system equipped with a 256‐element 2D matrix array and a portable X‐ray tube to visualize needle insertion and contrast agent dynamics. To capture both needle position and soft tissue anatomy, we integrated a dual‐modality system combining XACT with pulse‐echo US using a 128‐element linear US array. Experiments were conducted on both tissue‐mimic phantoms and soft tissue samples. GPU‐accelerated algorithm has been developed for 3D XACT image reconstruction. Results The results demonstrate the 3D capabilities of XACT imaging for interventional procedures, including monitoring of needle placement and tracking of contrast agent dynamics. The imaging speed reached up to 3∼4 s per frame, constrained by the repetition rate of the X‐ray source and signal to noise ratio. The dual‐modality approach provided clear visualization of the needle's position and the surrounding soft tissue structures, achieving imaging resolution around 2 mm. Conclusions This study demonstrates that XACT imaging is feasible to be used for IR. Its 3D imaging capability with faster imaging speed would be an alternative to cone beam CT and its capability to combine US imaging will provide richer information for soft tissue

Abstract Background: Patients with residual invasive disease after neoadjuvant chemotherapy (NAC) for HER2-positive breast cancer remain at high risk for recurrence even with standard adjuvant trastuzumab emtansine (T-DM1). H2NVAC, a multi-epitope HER2 peptide vaccine, has previously demonstrated the ability to elicit robust and durable immune responses. Here, we assessed the safety and early immunogenicity of H2NVAC in combination with T-DM1 in this high-risk population. Methods: Patients with stage II-III HER2-positive breast cancer and residual invasive disease following NAC and HER2-directed therapy received standard adjuvant T-DM1 alongside six priming doses of H2NVAC administered every 3 weeks. The primary endpoint was the occurrence of dose-limiting toxicity (DLT) within 21 days of the first vaccination, with adverse events graded per CTCAE v5.0. Immunogenicity assessments included HER2-specific T-cell responses measured by IFNγ ELISpot and HER-specific serum antibodies measured by ELISA at baseline and 30 days after the sixth priming dose. Results: 20 patients were enrolled. H2NVAC plus T-DM1 was well tolerated with no DLTs observed. All treatment-emergent AEs were grade 1-2, with fatigue (grade 1 60%, grade 2 5%), peripheral sensory neuropathy (grade 1 35%, grade 2 10%), elevated alkaline phosphatase (grade 1 40%), nausea (grade 1 35%, grade 2 5%), arthralgia (grade 1 30%), and injection-site reactions (grade 1 50%) being most common. Robust vaccine-specific T-cell responses by ELISpot were observed in 94% of evaluable patients, who mounted HER2-specific T-cell responses at 30 days after the sixth priming dose, with a mean 197-fold increase over baseline. Further CYTOF analysis showed a significant decrease in exhausted T-cell phenotypes, with reduced LAG3 and TIM3 expression on both CD4+ and CD8+ T cells. For antibody responses by ELISA, 26% of patients developed HER2 protein-specific antibody responses at this time point. There was no significant increase in antibodies to H2NVAC peptides or to unrelated tumor antigens (p53, IGFBP2, TERT, myoglobin) at 30 days after the sixth vaccine. Ongoing correlative analyses will assess the evolution of immune responses at later time points following completion of T-DM1 therapy. Conclusions: Concurrent administration of H2NVAC with T-DM1 was safe and did not increase toxicity beyond single-agent T-DM1. To our knowledge, this is the first study to demonstrate that a cancer vaccine can be delivered concurrently with an antibody-drug conjugate without increasing adverse effects while still eliciting robust T-cell responses. Ongoing analyses will further define the kinetics and durability of vaccine-induced antibody and T-cell responses at later time points, as well as evaluate the efficacy of H2NVAC in reducing recurrence risk in the randomized phase 2 trial. Citation Format: Saranya Chumsri, Sharmila Giri, Andy J. Ness, David W. Hillman, Nadine Norton, Davitte Cogen, Brian M. Necela, Aziza Nassar, Donald W. Northfelt, Pooja Advani, Rohit Rao, Alvaro Mareno-Aspitia, Brenda Ernst, Kathryn J. Ruddy, Matthew P. Goetz, Keith L. Knutson. Safety, tolerability, and early immune responses in the safety run-in of an HER2 multi-epitope vaccine combined with T-DM1 in residual HER2-positive breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 6715.