Citations

Abstract Epcoritamab and glofitamab are CD20-directed bispecific antibodies (BsAbs) approved in the United States for relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL). Limited data exist for patients treated outside of trials. Patients with R/R DLBCL receiving commercial epcoritamab or glofitamab between 1 January 2023 and 15 October 2024 were collected from 21 United States institutions. Among 245 patients, 156 received epcoritamab and 89 received glofitamab, 113 were refractory to front-line therapy, 40 had MYC and BCL2 and/or BCL6 rearrangements, 147 received prior chimeric antigen receptor T-cell therapy, and 174 patients would have been ineligible for registrational trials. The overall response rate (ORR) for epcoritamab and glofitamab was 51% (23% complete response, [CR]) and 53% (30% CR), respectively. Median progression-free survival (PFS) was 2.6 months (95% confidence interval [CI], 2.0-3.8 months), and median overall survival (OS) was 7.8 months (95% CI, 6.2-11.0 months). The 6-month PFS was 36% (95% CI, 30-44) and the 6-month OS was 60% (95% CI, 54-67). Both trial ineligibility and undetectable CD20 pre-BsAbs portended shorter PFS and OS. Of 17 individuals with paired biopsies, 15 (88.2%) lost CD20 expression after BsAbs with a median time to progression of 3.7 months. This analysis including patients with R/R DLBCL shows the ORR to CD3/CD20 BsAbs was comparable to pivotal trials, although PFS and OS were lower. Baseline undetectable levels of CD20 were associated with poor outcomes. These results demonstrate the activity of BsAbs in R/R DLBCL, and underscore the importance of target antigen expression.

1652 Background: Tarlatamab is a bispecific T-cell engager targeting DLL3 that has shown promise as a therapy in small cell lung cancer. Administering tarlatamab requires careful consideration of immune-related adverse events (AE), including cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Prescribing information recommends patients to be monitored for 22-24 hours in an appropriate healthcare setting for cycle 1 (C1), days 1 and 8. At Mayo Clinic in Rochester MN (MCR), tarlatamab is initially administered in a hospital-based outpatient (HBO) setting utilizing an innovative remote patient monitoring system (RPM). In this study, we describe our RPM process and patient outcomes thus far. Methods: We retrospectively reviewed records of patients treated with tarlatamab from August through December 2024. All patients received tarlatamab in the HBO setting and were enrolled into RPM for C1, days 1–10. Patients attended daily HBO visits on days 1–3 and 8–10 of C1 and were required to stay within 30 minutes of the hospital with a 24-hour caregiver for 48 hours following infusion days in C1-2. Data on patient characteristics, frequency of RPM alerts, escalations, rate of CRS & ICANS, and need for hospitalizations were reported using descriptive metrics. Results: As part of RPM, patients are provided with a kit containing preconnected Bluetooth-enabled devices to measure vital signs (VS), including blood pressure (BP), heart rate (HR), temperature (T), and pulse oximetry (SpO2). The kit also includes a cellular-enabled tablet for electronic ICANS questionnaires, which upload directly into our electronic medical record system. Patients are required to log VS four times daily, monitored in real-time by a centralized virtual RPM nursing (RN) team. Embedded decision trees trigger alerts, prompting the RN team to contact patients and follow care pathways for escalations as needed. Among the 16 patients treated, the median age was 68 years, and the median ECOG PS was 1. During the 10-day RPM period, a total of 2,233 VS entries were recorded. Of these, 88% (14/16) of patients had alerts triggered, with a median of 2 alerts per patient. Alerts were mostly for out-of-range systolic BP (56%), HR (56%), and T (25%), with none for SpO2. The RN team escalated alerts in 50% (8/16) of the patients. Overall, 38% (6/16) of patients were managed entirely in the HBO setting. Among the 63% hospitalized, 56% had CRS limited to grade (G) 2, and 31% had ICANS limited to G3. Two patients were hospitalized for other indications. The mean length of stay was 2.6 days, with no ICU admissions. Conclusions: Our experience shows that frequent monitoring required with tarlatamab can be safely and effectively executed in an outpatient setting with the utilization of an RPM system. It can potentially minimize the burden of hospitalizations for patients and the healthcare system.

7075 Background: Hepatosplenic T-cell lymphoma (HSTCL) is a rare, aggressive peripheral T-cell lymphoma arising primarily from γδ T-cells. It carries a poor prognosis and resists conventional chemotherapy. Most reports on HSTCL are case-based. This study comprehensively analyzes a large cohort, evaluating treatment strategies and survival outcomes. Methods: This retrospective study included patients (pts) with pathologically confirmed HSTCL diagnosed between 2000-2024, consecutively seen at Mayo Clinic MN. Clinical, pathological, genomic, and treatment-related data were extracted when available. Descriptive statistics were used to summarize baseline characteristics. Time-to-event analyses, including Kaplan-Meier estimates, median overall survival (OS), and survival time estimates were conducted from the date of diagnosis. Results: A total of 20 patients with newly diagnosed HSTCL were included, with a median age of 57 years (range: 35-71). The cohort was predominantly male (70%) and non-Hispanic (93%). Molecular data was available for five patients, revealing abnormalities in STAT5B, MLL3 deletion, TP53, EZH2, TERT, and NF1 E291D . The median follow-up was 27.6 months (m) with a median OS of 17.6 m (95% CI: 11.2 - NA). First-line treatment was anthracycline-based in 68% of pts and non-anthracycline-based in 32%, with higher response rates in the latter group (50% vs.83%). Although non-anthracycline regimens showed a trend toward improved 3-year OS (100% vs. 29%) the difference was not statistically significant (p = 0.16). Achieving a complete response to first-line therapy was also associated with a trend towards a better 3-year OS compared to refractory disease (80% vs. 50%, p = 0.17). Most pts (79%) underwent hematopoietic stem cell transplant (HSCT), primarily allogeneic, with only one receiving autologous HSCT. First-line therapy before HSCT was evenly distributed between anthracycline (55%) and non-anthracycline (45%) regimens. HSCT recipients had significantly higher 3-year OS than non-recipients (83% vs. 33%, p = 0.017). Notably, the patient with a TP53 mutation has remained in remission for over a year post-allogeneic HSCT. Conclusions: HSTCL predominantly affects younger pts, with nearly half dying within a year. Allogeneic HSCT, rarely used in other NHL subtypes, improved survival. Non-anthracycline regimens and achieving CR trended toward better outcomes. Our study, leveraging a sizable cohort, highlights the need for targeted research and novel therapies to improve HSTCL management. Summary of survival outcomes in HSTCL. Characteristics Median OS (y) 3-Year OS (95% CI) 1.48 [0.93- NA] 46% [0.26 - 0.81] Transplant Transplant NA [NA - NA] 83% [0.58 - 1.00] No Transplant 1.02 [0.93 - NA] 33% [0.07 - 1.00] Treatment Anthracycline Based 1.02 [0.36 - NA] 29% [0.11 - 0.73] Non-Anthracycline Based 4.61 [NA- NA] 100% [1.00 - 1.00]

e19008 Background: Cytokine release syndrome (CRS) is typically reversible in CAR-T therapy, while hyperinflammatory syndromes like macrophage activation-like syndrome (MAS-L) and high-grade immune effector cell-associated hemophagocytic syndrome (IEC-HS) are associated with significant morbidity and mortality. Early interventions are critical for improving outcomes. We aim to analyze clinical cytokine assays and cellular phenotypes early in hyperinflammatory syndromes to identify profiles for severe cases to inform management decisions. Methods: This study included 113 CAR-T patients (pt) (September 2019-March 2024) with cytokine profiles (CP) performed at the second tocilizumab dose or with suspected hyperinflammatory states (CP1), followed by assessments at 24 hours (CP24) and 48 hours (CP48). 52 pts consented to blood (PB) and bone marrow (BM) cell immune phenotyping at pre-treatment (pre-LD) and day 1 for PB. Results: Among the 113 pts, CRS pts (N=74), when compared to MAS-L(N=19) & IEC-HS (N=20) at CP1, had lower levels of TNF (median in pg/mL; 31, 62.9, 47.7) , IL-18 (794, 1353, 2011), and MCP-1 (689, 2722, 2485.5). While MAS-L and IEC-HS had similar CP1 profiles, CP24 and CP48 differed between them: TNF & MCP-1 levels decreased in MAS-L but remained elevated or increased in IEC-HS. IL-18 was stable in MAS-L but increased steadily daily in IEC-HS. Infections were more frequent in IEC-HS (CRS: 43%; MAS-L: 58%; IEC-HS: 85%; p=0.002). Notably, patients who died with persistent E. faecium bacteremia had higher IL-18 in CP48. In the 52 pts with cell phenotypes available by flow, 33 had CRS, 18 MAS-L and 8 IEC-HS. The correlation between cell phenotypes and cytokine levels showed that elevated TNF at CP1 correlated with increased non-classical monocytes in pre-LD BM and higher NK and NK-T cells in pre-LD PB. Similarly, elevated IL-18 CP48 levels correlated with increased CD8 T-cells, NK-T cells, and intermediate monocytes in pre-LD PB, as well as increased NK cells at both pre-LD and day 1 (Table). Conclusions: We report distinct cytokine profiles in IEC-HS early in the inflammatory course post-CAR-T therapy. These elevated cytokines correlate with specific immune cell subsets, including BM-resident monocytes, intermediate monocytes with heightened cytokine trafficking and inflammatory capacity. This study demonstrates the feasibility for identifying potential biomarkers for early risk stratification and targeted interventions. Cytokine Sample source Immune cells R P value TNF CP1 BM pre-LD Non-classical monocytes (CD14loCD16+) 0.38 0.025 PB pre-LD Monocytes (All) 0.47 0.022 NK cells (CD56+CD16+) 0.34 0.024 NK-T cells (CD3+CD56+CD16-) 0.29 0.04 IL-18 CP48 PB pre-LD CD8+ T-cells 0.59 0.0093 NK-T cells (CD3+CD56+CD16-) 0.53 0.023 Intermediate monocytes (CD14+CD16+) 0.58 0.012 PB pre-LD NK cells (CD56+CD16+) 0.56 0.49 0.015 0.024

PURPOSE Cytokine release syndrome (CRS) of any grade occurs in 56%-80% of bispecific antibodies (BsAbs) used in multiple myeloma (MM). Risk mitigation strategies are required to expedite escalation of care if toxicities develop. The rarity of grade 3 or 4 CRS compels protocolized outpatient management of BsAbs as outpatient practice may avoid hospital admissions and costly resource utilization without compromising safety. MATERIALS AND METHODS Patients with MM who received BsAb step-up dosing (SUD) from August 23, 2023, to March 29, 2024, were enrolled. Baseline demographics, patient outcomes, and CRS management were reviewed to assess the safety of outpatient practice. Resource utilization was also analyzed. RESULTS In this study, 34 patients received outpatient SUD of BsAbs (teclistamab n = 17, talequetamab n = 17) with 16 remaining outpatient throughout the entire SUD period. CRS occurred in seven patients who did not require hospitalization, demonstrating the safety of outpatient management of BsAb toxicity, regardless of low-grade CRS. CRS was observed in 24 patients (maximum grade 2) and immune effector cell–associated neurotoxicity syndrome in four patients (maximum grade 3). All patients with CRS received steroids, including 12 patients at home when instructed. Tocilizumab was given to 13 patients, accounting for 18 doses. If all doses of BsAbs and tocilizumab were given outpatient, the medication margin would be $115,004 in US dollars (USD). CONCLUSION An outpatient-based practice for BsAb administration demonstrated safety and cost savings. The description of our practice and results of this study provide valuable insights into the safety, feasibility, and resource stewardship of outpatient management of BsAbs. Future research should attempt to predict and stratify CRS risk to deliver a tailored supportive strategy and continued increase of outpatient management.

Abstract Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma involving the brain, cerebrospinal fluid, or retina/vitreous without systemic involvement. Induction with high-dose methotrexate (HD-MTX) followed by consolidation with autologous stem cell transplant (auto-SCT) has become the standard treatment paradigm for most patients. However, limited data are available regarding the efficacy of a maintenance approach with HD-MTX. Herein, we retrospectively reviewed the characteristics and outcomes of 148 patients diagnosed with PCNSL between October 2010 and June 2022, who underwent HD-MTX–based induction therapy followed by either auto-SCT consolidation (n = 70) or HD-MTX maintenance therapy (n = 37). At a median follow-up time of 4.5 years, the progression-free survival (PFS) was 8.3 years and the overall survival (OS) was not reached. Compared to patients who underwent auto-SCT, patients who received maintenance HD-MTX had a higher median age at diagnosis of 72 vs 62 years and a trend toward higher proportion of patients being Eastern Cooperative Oncology Group 2 or higher (41% vs 29%). At 5-years postinduction treatment initiation, the PFS rates in the auto-SCT cohort and HD-MTX maintenance cohort were 74.6% and 72.6%, respectively, and the OS rates were 76.0% and 82.4%, respectively. Overall, there was no significant difference in PFS or OS based on postinduction management strategy. Our data suggest that maintenance HD-MTX may be a reasonable, time-limited treatment strategy for patients with PCNSL responding to initial induction therapy.

Cytokine release syndrome (CRS) commonly occurs during initiation of bispecific T-cell engaging therapy (BsAbs) for multiple myeloma (MM) (NEJM 2022;387:495, NEJM 2022;387:2232, Nat Med 2023;29:2259). Pre-medications, step-up dosing (SUD), and monitoring minimize high-grade toxicity risk, while protocolized outpatient (OP) management of BsAbs and toxicities could reduce resource utilization and improve patient satisfaction. At Mayo Clinic, SUD, clinical assessment and grade 1 CRS management occurs primarily as an OP for patients with MM receiving BsAbs. This study aims to assess the current OP management practices of BsAbs and related toxicities including patient outcomes, admission rates, and resource utilization. Patients with MM who received SUD from August 23, 2023, to March 29, 2024, were included. Baseline demographics, patient outcomes, and CRS management details are summarized. Resource utilization outcomes included level of care, length of hospital stay (LOS), and high-cost drug administration. 38 patients received MM BsAbs during the study timeframe. 34 patients initiated OP SUD (teclistamab n=17 and talquetamab n= 17). The median age was 71 years, 59% were male, 82% were white, and 88% had Medicare coverage. Median number of prior lines of therapy was 6. There were 317 OP encounters with a median of 10 encounters per patient. Of these, 72% were planned in-person assessments, 5% were unplanned clinic visits for potential toxicity-related symptom assessment, and 20% were phone visits that obviated in-person assessment. 66 of 68 doses of talquetamab (total of 1,628 mg) and 48 of 50 doses of teclistamab (total of 2,048 mg) were administered and billed in the OP setting. 24 patients (71%) that initiated OP SUD developed CRS (grade 1 n=16, grade 2 n=7). Management of the initial CRS event included steroids and acetaminophen, with or without tocilizumab. 2,600 mg of tocilizumab administered in the OP setting. Recurrent CRS was seen in 5 patients and also treated entirely OP. 4 patients developed ICANS (grade 1 n=3, grade 3 n=1). Hospitalization following OP SUD initiation occurred in 18 (53%) patients at some point during treatment. Indications included grade 2 CRS (n=6), ICANS (grade 1 n=3), refractory CRS (n=7), infection (n=1), GI bleed (n=1), planned observation for comorbidities or prior CRS (n=2), loss of caregiver (n=1), atrial fibrillation (n=1), heart failure (n=1), and pain crisis (n=1). Median LOS was 2 days. Recurrent admission occurred in 41% and median LOS was also 2 days for subsequent admissions. Two patients were admitted to the intensive care unit for hypotension or arrhythmia. 1 patient required dialysis. In total for SUD during the study time frame, 51 mg of teclistamab, 176 mg of talquetamab, and 8,240 mg of tocilizumab were billed under an IP encounter, which likely was due to inpatient administration or hospital admission within 72 hours of receiving the OP SUD. This descriptive study of our OP BsAb management practice demonstrated that 47% of patients remained OP, even with a CRS event. The CRS rate did not surpass those in landmark clinical trials and aligns with real-world data previously reported (Blood Cancer J 2024;14:35.). Availability and use of patient monitoring capabilities along with lack of sentinel outcomes emphasizes the safety of an OP BsAb practice. Drivers of financial burdens and savings include location and reimbursement of high-cost drugs and admission rates. Median LOS was less than half of what's anticipated with inpatient SUD. Inpatient administration of high-cost drugs can be more costly compared to OP due to associated medical costs and insufficient reimbursement in a population primarily insured by Medicare which reimburses inpatient mediations based on the Diagnostic Related Group (DRG) unless the medication has New Technology Add on Payment (NTAP). Using expected Medicare reimbursement rates and wholesale acquisition costs while excluding variable DRG reimbursement and NTAP impacts for teclistamab, the total net revenue improvement for shifting use of all teclistamab, talquetamab, and tocilizumab OP is $115,004 for the period analyzed (CMS.gov 2024). In conclusion, OP management of patients undergoing SUD for MM BsAbs is safe and has substantial reductions in resource utilization and costs.

Introduction: Outcomes from multidisciplinary lymphoma tumor boards in the molecular era are limited, and the effects of transitioning to virtual formats during the COVID-19 pandemic are not well-documented. This study evaluates how the transition of the Mayo Clinic Lymphoma Tumor Board to a virtual format has impacted its effectiveness and operations. The board, part of the International Mayo Clinic Care Network (MCCN), involves case presentations, subspecialist reviews, and collaborative recommendations. Methods: The Mayo Clinic Lymphoma Tumor Board, an integral part of the Mayo Clinic Care Network (MCCN), conducted a comprehensive review of lymphoma cases from 2014 to 2024. The board's review process involves a structured approach including the presentation of clinical case details, radiology and hematopathology findings, proposed treatment options, relevant literature review, and discussions. From 2014 to 2024, the Mayo Clinic Lymphoma Tumor Board reviewed a total of 722 patients. The review process involves a multidisciplinary team, including physicians, pharmacists, clinical research associates, and trainees. Recommendations and changes related to radiology interpretation, pathologic diagnosis, and treatment approaches were documented and tracked prospectively. In March 2020, the board transitioned to a virtual format due to the COVID-19 pandemic. This shift allowed for remote participation and continued collaborative review while maintaining the board's structured approach and documentation practices. Results: In a total of 722 patients, changes in care were identified in 423 patients, including 287 with newly diagnosed lymphoma and 136 with relapse or refractory disease. Among those who experienced changes, 94 had diffuse large B-cell lymphoma, 49 had follicular lymphoma, 39 had marginal zone lymphoma, 36 had classical Hodgkin lymphoma, and 29 had mantle cell lymphoma. Prior to the COVID-19 pandemic, 431 patients were analyzed, with 217 (50.3%) experiencing changes. A total of 268 changes were documented among these patients. Changes in radiologic interpretation occurred in 9 patients (2.1% of 431 total patients). Pathologic diagnosis changes were noted in 42 patients (9.7%). Additional testing was recommended for 73 patients (16.9%), and clinical management was altered for 144 patients (33.4%). After transitioning to a virtual format, 291 patients were reviewed post-COVID, with 206 (70.8%) having recommended changes. The total number of change recommendations was 322, reflecting increases across all components compared to previous data, with adjustments for varying numbers of patients reviewed. Specifically, radiologic interpretation changes occurred in 21 patients (7.2%), pathologic diagnosis changes in 57 patients (19.6%), additional testing recommendations for 85 patients (29.2%), and clinical management alterations in 159 patients (54.7%). Conclusion: Transitioning to a virtual format in the Mayo Clinic Lymphoma Tumor Board's continued to demonstrate the effectiveness, with increased changes in diagnostic interpretations and clinical management. These results illustrate the potential of virtual tumor boards to improve collaborative decision-making and adapt to evolving clinical needs.