Citations

Abstract Introduction CAR T cell treatment is the standard of care for patients (pts) with primary refractory and relapsed large B-cell lymphoma (LBCL) within the first 12 months of chemoimmunotherapy, or for those unfit for autologous stem cell transplant (ASCT) regardless of timing of relapse. Consequently, the role of ASCT is limited to pts with late relapse (>12 months) who achieve a complete or partial response (CR or PR) to salvage therapy and are deemed eligible for ASCT based on comorbidities and performance status. In this report, we evaluated post-ASCT outcomes in this population of pts. Methods We conducted a retrospective cohort study using publicly available data from the Center for International Blood and Marrow Transplant Research (CIBMTR). Adult pts (age ≥18 years) with DLBCL, NOS, and high-grade large B-cell lymphomas (HGBL) who relapsed after having responded to initial treatment and who remained on response for at least 12 months since diagnosis were selected. We considered for this analysis only pts who achieved a CR or PR after salvage treatment at the time of relapse, documented on pre-ASCT CT or PET scan (per the 2014 Lugano definition). CIBMTR databases used for this study included pts who received ASCT from 2013 to 2021. We compared baseline characteristics between ASCT in CR vs PR using the Wilcoxon rank sum test for continuous variables and the Pearson's χ2 test for categorical variables after ignoring missing data. Primary endpoints included Progression-free survival (PFS) and overall survival (OS). Non-relapse mortality (NRM) and relapse rate were among the secondary endpoints. Results 182 were included in the analysis: 100 were in CR and 82 in PR before ASCT. The median age at ASCT was 60 years (range, 26-79). Race distribution was similar across CR and PR pts. Advanced-stage disease at diagnosis (stage III–IV) was seen in 61% of CR pts and 55% of PR pts. High-grade B-cell lymphoma (HGBL) with MYC and BCL2 and/or BCL6 rearrangements was similar in the CR and PR groups (7% vs 4%). The median number of lines of treatment before ASCT were identical in CR and PR pts (N=2). BEAM was the most frequently used transplant conditioning regimen in both groups (80%). Median follow-up after ASCT was 34 months (range, 1–95): it was 37 months (range 1-95) in the CR group and 26 months (range 1-79) in the PR group For the entire cohort, OS at 3 years was 67.6% and PFS was 50.6%. NRM was 1.7% at 100 days and 3.4% at 1 year. Cumulative incidence of relapse at 3 years was 43.9%. The NRM analysis showed no statistically significant difference between pts in CR and PR. The 3-year OS for CR pts was 73.9%% compared to 59.4% for PR pts (95% CI, 0.334-0.99; p=.044). The 3-year PFS for CR pts was 59.8%, compared to 38.6% for PR pts (95% CI, 0.321-0.784; p=.001). The median PFS for CR pts was 52.01 months, compared to 14.05 months for PR pts. The cumulative incidence of relapse at 3 years in CR and PR pts was 35.2% vs 55.7%, respectively (95% CI, 0.311-0.811; p=.003.). Higher age (HR 1.03; p=.026) and number of previous lines of treatment (HR 1.43; p=.002) were associated with inferior OS. For PFS, no variables showed any significant impact in univariable analysis. The stepwise multivariable analysis showed that only the number of previous treatments had a significant impact on the OS (p=.009), while undergoing ASCT on a PR was the only factor significantly associated with shorter PFS (HR 1.41; 95% CI, 1.09-1.82; p=.029). Conclusion This dataset supports that ASCT provides high efficacy in pts experiencing late relapses (after 12 months) achieving CR following pre-transplant savage and validates the value of achieving CR. Outcomes for PR are inferior, and this analysis provides a benchmark for future investigations. At this time, until convincing on other non-transplant treatment show superior outcomes in this setting, ASCT remains a standard of care for fit pts with chemo-sensitive late relapsed DLBCL. In this group of patients, who have a better prognosis compared to patients who relapse within a year the major hurdle is achieving a remission pre-ASCT.

Abstract Introduction: IRAKLIA is an international, open-label, non-inferiority (NI) trial (NCT05405166) investigating isatuximab (Isa) subcutaneous (SC) vs intravenous (IV) administration, plus pomalidomide-dexamethasone (Pd) and the first Phase 3 multiple myeloma (MM) trial using an on-body injector (OBI). IRAKLIA demonstrated NI in its co-primary endpoints: overall response rate (ORR) and steady state trough concentration (Ctrough; Cycle(C) 6 Day(D) 1 predose). IsaOBI offers hands-free administration of flat-dose Isa, a small, hidden, retractable needle to prevent sharps injury and low-pressure delivery. Here, we examine the effect of body weight (BW) on pharmacokinetics (PK) as well as efficacy and safety outcomes with flat-dose IsaOBI vs IV + Pd in IRAKLIA. Methods: Patients (pts) with relapsed/refractory MM ≥18 years (yr) with ≥1 prior line of therapy (LOT) were randomized 1:1 to IsaOBI (1400mg; n=263) or IV (10mg/kg; n=264 weekly in C1, then every 2 weeks + P (4mg/day, D1–21) + d (40mg [20mg if ≥75yr] weekly) in 4-week cycles. This analysis is run by BW (≤65kg, >65–≤85kg, >85kg) which was a stratification factor, and extreme BW (≤50kg, >50–≤100kg, >100kg). Results: Number of pts per BW group were: ≤50kg [OBI n=16, IV n=14], ≤65kg [OBI n=84, IV n=85], >65–≤85kg [OBI n=117, IV n=118], >85kg [OBI n=62, IV n=65], and >100kg [OBI n=22, IV n=22]. Baseline (BL) demographic and disease characteristics were generally balanced across BW groups for IsaOBI vs IV, including age (median 66yr) and prior LOT (median 2). However, in the >100kg group, more IsaOBI vs IV pts exhibited poor prognostic characteristics including plasmacytoma, International Staging System Stage II/III disease, beta 2-microglobulin level ≥5.5mg/L, estimated glomerular filtration rate <60mL/min/1.73m2 and a lower very good partial response (VGPR) rate as best overall response at last regimen. Flat-dose IsaOBI showed adequate exposure (C2D1 Ctrough) for all BW groups, with geometric mean ratios (90% CI) vs IV >1: ≤65kg (1.628 [1.294–2.048]), >65–≤85kg (1.303 [1.089–1.560]) and >85kg (1.006 [0.817–1.239]). IsaOBI ORRs were comparable to IV across BW: ≤65kg, 66% vs 71% (relative risk [RR]: 0.928), >65–≤85kg, 70% vs 70% (RR: 1.009), and >85kg, 81% vs 72% (RR: 1.115). For extreme BW groups, ORRs (95% CI) were similar between IsaOBI and IV for ≤50kg group [56% vs 60%] and for >50–≤100kg [72(66–78)% vs 70(63–76)%] but lower [68% vs 86%] in >100kg group. An exposure-response (E-R) analysis showed the impact of BW on response: IsaOBI pts ≤50kg tended to respond less vs IsaOBI pts >50kg despite correct exposure because they were confounded by BL disease characteristicsincluding a higher proportion of high-risk cytogenetics and plasma cells in the bone marrow vs other BW group pts. For IsaOBI and IV, Grade (Gr)≥3 treatment-emergent adverse events (TEAEs) and Gr≥3 treatment-related TEAEs decreased with increasing BW. They were similar between arms in ≤65kg group (OBI vs IV, Gr≥3 TEAEs: 87% vs 88%; Gr≥3 treatment-related TEAEs: 73% vs 77%). A similar trend was observed in extreme BW groups along with similar incidences between arms in ≤50kg group. While TE serious AEs (TESAEs) and treatment-related TESAEs decreased with increasing BW for IsaIV, incidence was stable in the IsaOBI arm. OBI arm OBI Gr5 TEAEs were similar between groups and arms, except for higher incidence in ≤65kg group (12% vs 5%) with OBI vs IV that was not reflected in ≤50 or >50–≤100kg groups. Treatment discontinuation rates for all drugs with IsaOBI vs IV were 14% vs 6% (≤65kg), 8% vs 10% (>65–≤85kg), and 2% vs 10% (>85kg). Similar incidence of Gr≥3 laboratory (lab) neutropenia was observed across BW in IsaOBI: 86.9% (≤65kg), 83.5% (>65–≤85kg) and 83.9% (>85kg). Higher rates of Gr≥3 lab neutropenia were observed in ≤50kg group (93.8%, IsaOBI vs 71.4%, IsaIV), which did not translate into higher rates of neutropenic complications (18.8% vs 14.3%). The E-R analysis revealed no relationship between Isa PK exposure and safety for OBI and IV arms. Conclusions: No notable impact from IsaOBI flat dosing was observed across BW groups. Flat-dose Isa OBI showed consistent safety and efficacy across different BW groups, with differences likely linked to BL disease characteristics according to the E-R analysis. The IsaOBI C2D1 Ctrough, a time-independent predictor of efficacy, was similar to, or higher vs IsaIV in each BW group, supportive of a flat dose providing adequate exposure without need for adjustment.

Abstract Background: Clonotypic peptide detection by mass spectrometry (MS) leverages monoclonal protein (M-protein) de novo sequencing and peptide quantification to enable ultra-sensitive blood-based monitoring of multiple myeloma (MM) patient M-protein kinetics. Etentamig is a 2nd generation BCMA x CD3 bispecific antibody that has shown promising efficacy and a favorable safety profile in heavily pre-treated patients with relapsed or refractory (RR) MM (Journal of Clinical Oncology, 43;16:suppl.7527). In the current study, we explored the depth and kinetics of MS M-protein response to etentamig monotherapy in serum samples from Phase 1 M22-466 (NCT03933735) study patients. The correlation between blood-based MS M-protein levels and bone marrow minimal residual disease (MRD) negativity as determined by next generation sequencing (NGS) was also evaluated. Method: Clonotypic peptide MS using M-Insight (Sebia/Corgenix) was performed on serum samples from a subset of MRD evaluable patients enrolled into the Phase 1 (NCT03933735) clinical trial of etentamig monotherapy in patients with RRMM. Bone marrow MRD negativity (<10-5 and 10-6) analysis was determined by NGS (clonoSEQ, Adaptive Biotechnologies). Patient pre-treatment (Cycle [C] 1 Day [D] 1) serum samples were digested with proteolytic enzymes to permit sequencing of the M-protein heavy and light chain. Clonotypic peptides specific to the patient's complementarity-determining regions were selected for quantification by MS. Clonotypic peptide quantification by MS was performed on available tracking peripheral blood samples at C2D1, C3D1, C4D1, and C5D1 time points post etentamig monotherapy treatment. Results: Twenty patients who were MRD evaluable and treated with 40 mg and 60 mg doses of etentamig with available serum samples collected from C1D1–C5D1 time points were selected for M-Insight evaluation. Of the 20 patients, 16 (80%) had at least one clonotypic peptide identified prior to etentamig treatment that was utilized for tracking at subsequent time points. Rapid decline in MS M-protein levels was observed in patients treated with etentamig, which strongly correlated with the patients' best International Myeloma Working Group (IMWG) response. At C3D1 post etentamig treatment, patients with complete response (CR)/stringent CR (n=9) demonstrated a significant decline from MS M-protein levels (median: 1.8±0.9 g/dL at C1D1 to 0.03±0.2 g/dL at C3D1) (P<0.001). All evaluable subjects (n=16) had detectable MS M-protein at all time points (n=80). The lowest detectable M-protein level observed in the current dataset was 44 mg/dL (lower limit of quantitation of assay: 10 mg/dL). Subsequent analysis of differences in kinetics between MRD-negative (<10-5) (n=8) and MRD-positive (n=8) patients revealed a deeper reduction in M-protein levels for MRD-negative patients (median 0.02±0.2 g/dL at C3D1 compared with 0.4±0.3 g/dL at C3D1 for MRD-positive patients). Among the 8 patients who achieved MRD negativity at 10-5 threshold, 5 patients also achieved <10-6 threshold, and serum MS M-protein levels remained detectable in these patients (0.07±0.2 g/dL). Conclusions: Using MS-based clonotypic peptide detection, rapid and deep decline in serum M-protein levels was observed in RRMM patients treated with etentamig. Strong concordance was observed between MS M-protein levels and IMWG response, including in patients achieving MRD-negative CR at <10-5 and 10-6thresholds. Non-invasive and ultra-sensitive M-protein detection is feasible in MM and may serve as a key biomarker for enhancing the detection of residual disease in the future.

Abstract Background Paroxysmal nocturnal hemoglobinuria (PNH) is a rare blood disorder characterized by uncontrolled terminal complement activation leading to intravascular hemolysis (IVH), thrombosis, and premature mortality. The complement C5 inhibitor (C5i) ravulizumab provides immediate, complete, and sustained inhibition of terminal complement activity through an 8-weekly weight-based dosing interval, resulting in control of IVH, reduced morbidity (thrombosis rate) and mortality (improved survival). Pivotal trials of ravulizumab have shown durable efficacy and safety (Kulasekararaj et al. Ann Hematol 2025). While real-world evidence supporting its use is accumulating, further data are needed to more comprehensively characterize its effectiveness and safety in routine clinical practice.Aims To evaluate the real-world effectiveness and safety of ravulizumab among US patients with PNH over 1 year, based on physician chart review data. Methods Medical chart data from 127 US patients with PNH who started ravulizumab between June 1, 2021 and May 31, 2023 were randomly selected and abstracted by 50 hematologists/oncologists from academic (n=25) or community (n=25) settings. Included patients were aged ≥18 years on the date of ravulizumab initiation (index), had ≥12 months of medical data pre- and post-index, and continued ravulizumab for ≥12 months, unless the patient died. Complement inhibitor (Ci)-experienced patients had previous eculizumab or pegcetacoplan use pre-index; Ci-naive patients had no previous use of any Ci pre-index. Outcomes included changes in lactate dehydrogenase (LDH), hemoglobin (Hb), and absolute reticulocyte count (ARC) up to 12 months post-index. Breakthrough IVH (BT-IVH) events (defined as LDH ≥2 × upper limit of normal [ULN; 246 U/L] and ≥1 of the following: anemia, dyspnea, hemoglobinuria, or fatigue) were assessed from index to earliest of death, loss to follow-up, ravulizumab discontinuation, or chart abstraction. Event rate was calculated per 10 person-years (PY).Results The sample included 69 Ci-naive (mean [standard deviation; SD] age: 51.4 [14.1] years; 59.4% male) and 58 Ci-experienced patients (mean [SD] age: 45.0 [14.7] years; 51.7% male; previous eculizumab: n=52; previous pegcetacoplan: n=6). In both respective cohorts, ravulizumab was associated with significant reductions in mean (SD) LDH level at month 12 (−348 [424] U/L and −20 [75] U/L; p<0.001 and p<0.05), with improvements observed from 1-month post-index. Similarly, mean (SD) Hb levels significantly increased over 12 months (2.2 [1.8] g/dL and 1.3 [1.5] g/dL, respectively; p<0.001 for both), with improvements seen as early as 1-month post-index. Significant reductions in mean (SD) ARC were observed 1-month post-index and were maintained for up to 12 months in Ci-naive patients (−45 [52] × 103/μL; p<0.001). This effect was not observed in Ci-experienced patients (−7 [85] × 103/μL; p=0.536). Over a median follow-up of 1.8 years (Ci-naive) and 1.6 years (Ci-experienced), 4 BT-IVH events occurred in 4 Ci-naive patients (5.8%; event rate: 0.30 per 10 PY), and 7 events occurred in 5 Ci-experienced patients (8.6%; event rate: 0.69 per 10 PY). All events were resolved without transfusion, dose modification, or discontinuation of ravulizumab, and no events resulted in thrombosis. Summary/Conclusion These real-world data from US adults with PNH showed that ravulizumab was associated with early and sustained significant and clinically meaningful improvements in hematological markers for PNH, in both Ci-naive patients and those with prior eculizumab or pegcetacoplan use. Ravulizumab treatment was associated with a low incidence of BT-IVH events, and all events were resolved without the need for transfusion, dose adjustment, or treatment discontinuation. Importantly, no thrombotic events occurred during these events. Despite the known differences in data collection between clinical trial and real-world populations, these findings align with an analysis of long-term clinical trial data from Kulasekararaj et al. (2025), which reported BT-IVH in 14.8% of C5i-naive (event rate: 1.0 per 10 PY) and 7.8% of eculizumab-experienced patients (event rate: 0.33 per 10 PY) with PNH over a follow-up period of up to 6 years (median: 3.9 and 2.7 years, respectively). Overall, this analysis supports the use of ravulizumab, with only 6–7 infusions per year, as an effective treatment for patients with PNH in the real-world setting.

Abstract Introduction: CAR T-cell therapy is an important treatment option for patients with relapsed or refractory (R/R) DLBCL. Three CAR T-cell products have received approval: axicabtagene ciloleucel (Yescarta), lisocabtagene maraleucel (Breyanzi), and tisagenlecleucel (Kymriah). Although direct head-to-head studies comparing the three therapies do not exist, clinical trials have revealed notable differences in response rates and remission rates among them. All three products induce CRS and ICANS; however, variations in the incidence and severity of these adverse effects have been observed. We utilized data from the National Inpatient Sample (NIS) to gain further insights into the incidence of various adverse events associated with different CAR-T products in DLBCL. Method: In this retrospective study, the 2022 NIS database was used to identify hospitalizations with DLBCL and those who received Yescarta, Breyanzi, or Kymriah using appropriate ICD-10-CM diagnostic and ICD-10-PCS procedure codes. Data on CRS, ICANS, infections, and adverse cardiac events were extracted using relevant ICD-10-CM codes. These outcomes were compared across different CAR-T products using Pearson's chi-square analysis. Multivariate logistic regression was also performed, adjusting for demographics, hospital-specific characteristics, and comorbidities. Results: We identified 1440 patients with DLBCL. Among these, 1100 patients (64.6% male; 70.7% Caucasian, 8.8% African American, 20.5% other ethnicities) received Yescarta, 90 patients (66.7% male; 82.4% Caucasian, 0% African American, 17.7% other ethnicities) received Kymriah and 250 patients (64% male; 82.6% Caucasian, 10.9% African American, 6.5% other ethnicities) received Breyanzi. The incidence of CRS was 52% for Breyanzi, 44.4% for Kymriah and 68.6% for Yescarta, and the difference was statistically significant by chi-square analysis (p = 0.03). This difference remained statistically significant for Kymriah after multivariate analysis [Adjusted Odds ratio (OR) = 0.3, CI 0.1 to 0.9, p=0.032], but not for Breyanzi (Adjusted OR = 0.3, CI 0.1 to 0.9, p=0.032) in comparison to Yescarta. The incidence of ICANS was 16% for Breyanzi, 22.2% for Kymriah, and 33.2% for Yescarta, with a statistically significant difference observed by chi-square analysis (p = 0.05). This difference remained statistically significant for Breyanzi after multivariate analysis [Adjusted OR = 0.3, CI 0.1 to 0.6, p=0.002], but not for Kymriah (Adjusted OR = 0.6, CI 0.1 to 2.9, p=0.551) in comparison to Yescarta. Among cardiovascular events, there was no significant difference in the incidence of acute myocardial infarction (Yescarta vs Kymriah vs Breyanzi, 0.5% vs 0% vs 0.2%, p = 0.487), stroke (0.5% vs 5.6% vs 2%, p = 0.07), cardiogenic shock (0.5% vs 0% vs 0%, p = 0.880), and arrhythmias (20.9% vs 27.8% vs 32%, p = 0.258) among these CAR T-cell therapies. Furthermore, there were no significant differences in the incidence of infectious complications, including pneumonia (5.9% vs 5.6% vs 2%, p = 0.510), sepsis (5% vs 5.6% vs 6%, p = 0.962), or septic shock (2.3% vs 0% vs 0%, p = 0.535) among these CAR T-cell therapies. There was no difference in all-cause in-hospital mortality across these therapies (2.3% vs 5.6% vs 2%, p = 0.692). Conclusion: Kymriah showed lower CRS rates and Breyanzi showed lower ICANS rates in comparison to Yescarta in our study. All CAR T-cell therapies have the potential to cause infections and cardiac events, which require monitoring, early identification and prompt treatment. When selecting among various CAR T-cell products, several factors must be considered, including the patient's lymphoma type, prior treatment history, manufacturing turnaround time, cost, availability, and potential short-term and long-term side effects. The limitations of our study include its retrospective nature, reliance on ICD-10 codes to identify patients with adverse events, and the absence of longitudinal data on long-term adverse events. Nevertheless, this study provides essential insights for hematologists regarding the incidence of specific adverse events associated with different CAR T-cell products within the real-world population.

Abstract Background: Chronic Lymphocytic Leukemia (CLL) is the most prevalent leukemia among adults in Western populations, disproportionately affecting the elderly, with a median age at diagnosis of approximately 70 years. Over the past two decades, significant advancements in therapeutic options, including Bruton tyrosine kinase (BTK) inhibitors, BCL-2 antagonists, and monoclonal antibodies, have improved clinical outcomes. However, despite these advances, limited data exist on long-term mortality trends and disparities in CLL outcomes among older adults in the United States. Understanding such patterns is critical to guiding geriatric oncology care, identifying gaps in healthcare delivery, and informing public health strategies. Methods: We conducted a population-based analysis using the Centers for Disease Control and Prevention Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) Underlying Cause-of-Death database. We identified all deaths among individuals aged ≥65 years from 1999 to 2020 in which CLL (ICD-10 code C91.1) was listed as the underlying cause. Mortality data were stratified by sex, age group (65–74, 75–84, ≥85), U.S. Census region, urban-rural classification, state, and place of death. We calculated crude mortality rates (CMRs) and age-adjusted mortality rates (AAMRs) per 100,000 persons, standardized to the U.S. 2000 population. Joinpoint regression analysis was used to assess temporal trends in AAMRs and compute annual percent changes (APCs) and average annual percent changes (AAPCs), with statistical significance set at p<0.05. Results: Between 1999 and 2020, a total of 85,371 CLL-related deaths occurred among U.S. adults aged ≥65 years. The overall AAMR declined from 11.18 per 100,000 in 1999 to 7.75 in 2020, reflecting a significant downward trend (AAPC: -1.86%; 95% CI: -2.18 to -1.54; p<0.0001). Men consistently exhibited higher mortality rates (AAMR: 13.48) than women (AAMR: 6.45), though the mortality decline was more pronounced among women (AAPC: -2.10% vs. -1.65%, respectively; both p<0.0001). Regional disparities were evident, with the Midwest reporting the highest AAMR (10.63), and the West the lowest (8.71). Urbanization analysis revealed higher mortality in non-metropolitan areas (AAMR: 10.33) than metropolitan ones (AAMR: 9.08), though both experienced significant declines over time. Age-stratified analysis showed the steepest declines in the 65–74 age group (AAPC: -3.91%; p<0.0001), followed by those aged 75–84 years (AAPC: -1.96%) and ≥85 years (AAPC: -0.25%). States with the highest mortality included Minnesota, Iowa, and South Dakota, while Hawaii, Nevada, and New Mexico had the lowest. Most deaths occurred in medical facilities (43.8%), followed by home (26.7%), nursing homes/long-term care (19.5%), and hospice (5.6%). Conclusion: CLL-related mortality among the U.S. geriatric population declined significantly between 1999 and 2020, likely reflecting the impact of therapeutic innovations and improved disease management. However, substantial disparities persist across sex, age, region, urbanization, and state-level subgroups. These findings underscore the importance of equitable access to modern CLL treatments and the need for targeted interventions to reduce mortality in high-risk, underserved older populations. Efforts to close these gaps will be essential in optimizing outcomes in the era of personalized cancer care for aging Americans.

Abstract Introduction A 2017 survey by the American Society of Hematology found a widespread perceived shortage of classical hematologists in the US, which was compounded by a low trainee interest in the field (<5%) (Masselink LE, Blood Adv 2019). Recently, we reported that among hematologist/oncologists at the 64 National Cancer Institute (NCI)-designated cancer centers with clinical programs, only ~5% identify as classical hematologists, despite 15% of them including classic hematology (CH) patients in their practice (Go LT, Blood Adv, in press). However, there remains limited data on CH consult volumes at NCI-designated cancer centers (West CV, JCO Oncol Pract 2023). This study aimed to evaluate the volume and nature of CH outpatient consults at the Mayo Clinic Comprehensive Cancer Center (MCCC). Methods We reviewed electronic medical records to identify all completed outpatient consults in CH, malignant hematology (MH), and solid tumor oncology at MCCC in Rochester, Minnesota from January 1 to December 31, 2024. Consults were defined as either external or internal referrals for new patients seen in CH outpatient clinic. CH consults were further categorized by referral reasons and the type of physician (CH, MH, or fellow) performing the consultations. CH physicians were defined as those whose clinical practice primarily focuses on non-malignant hematologic conditions; one advanced practice provider (APP) was included in this group. Inpatient consults, electronic consults, and return visits were excluded. Results In 2024, a total of 17,153 outpatient consults were completed. Of these, 13.4% were CH, 30.5% were MH and 56.1% were solid tumor oncology. Among CH consults, the most common referral reasons were abnormal blood counts (68.3%), bleeding disorders (10.6%), thrombosis (11.8%), and other hematologic diagnoses (9.3%). Within abnormal blood counts, the leading indications were anemia (50.7%), thrombocytopenia (15.3%), leukopenia (11.0%), leukocytosis (9.1%), and pancytopenia (7.0%). Among bleeding disorders, the top reasons included suspected bleeding diathesis (49.4%), von Willebrand disease (24.5%), Hemophilia A (4.1%), Factor VII deficiency (3.7%), and platelet qualitative defect (3.4%). Thrombosis-related consults were most often for pulmonary embolism or deep vein thrombosis (43.2%), antiphospholipid syndrome (17.7%), thrombophilia (16.2%), portal vein thrombosis (4.1%), and splenic infarct (2.6%). The top ten referrals for a specific hematologic diagnosis were iron deficiency anemia (29.2%), pulmonary embolism or DVT (13.5%), immune thrombocytopenic purpura (10.3%), von Willebrand disease (6.9%), hemoglobinopathy (5.5%), antiphospholipid syndrome (5.5%), thrombophilia (5.1%), anemia of chronic kidney disease (2.4%), aplastic anemia (1.5%), and hereditary spherocytosis (1.4%). Of the 114 physicians at MCCC during the study period, 55 (48.2%) were medical oncologists, 54 (47.4%) primarily practiced MH, and only 5 (4.4%) were dedicated CH physicians. Despite comprising only 4.4% of the hematology/oncology workforce, CH physicians or fellows completed the majority (86.1%) of CH consults; MH physicians completed 13.8%. Conclusion CH consults represent a substantial portion of outpatient hematology referrals at MCCC, primarily for diagnostic evaluation of cytopenias or thrombotic/bleeding symptoms. However, a striking mismatch exists between CH physician representation (4.4%) and CH consult volume (13.4%). This imbalance has implications for quality, timeliness, and continuity of care for patients with non-malignant hematologic conditions. Our findings underscore the urgent need to expand recruitment and career development pathways in CH to address a huge clinical demand.

Abstract Background: Mosunetuzumab, a CD20xCD3 bispecific antibody, can be administered in the outpatient setting for a fixed duration. Mosunetuzumab by intravenous (IV) administration is FDA- and EMA-approved in relapsed/refractory (R/R) FL after ≥2 prior lines of therapy. Interim results from the Phase II MorningSun study (NCT05207670) demonstrated promising efficacy and manageable safety of mosunetuzumab SC in pts with previously untreated HTB FL (Flinn et al. ASCO 2025). We report 12-month follow-up efficacy and safety data of mosunetuzumab SC in pts with previously untreated HTB FL in the MorningSun study, including pts who received optional maintenance therapy. Methods: Pts with previously untreated HTB FL, per Groupe D'Etude des Lymphomes Folliculaires criteria, and Eastern Cooperative Oncology Group performance status of 0–2 were enrolled, primarily from United States (US) community sites. Mosunetuzumab SC was administered as step-up dosing in Cycle (C)1 (Day [D]1, 5mg; D8, 45mg; D15, 45mg) followed by 45mg on D1 of each 21-day cycle, for up to 17 cycles (1 year). Pts with a partial or complete metabolic response (CMR) after C17 could receive optional mosunetuzumab maintenance treatment (45mg every 8 weeks for up to 1 year). The primary endpoint was progression-free survival (PFS) rate at 1 year. Key secondary endpoints included objective response rate (ORR), duration of response (DOR), duration of complete response (DOCR) and safety. Exploratory analysis of ctDNA levels was performed using the AOA-NHL assay. Results: As of February 10, 2025, 103 pts were enrolled (n=82 pts from community sites, n=21 pts from academic sites). Overall, the median age was 65 years (range: 24–86), 51.5% of pts were female and most pts had Ann Arbor stage III/IV disease (91.3%) and a FLIPI score ≥2 (78.6%). In total, 69 pts completed initial treatment (17 cycles), 33 discontinued (primarily due to progressive disease [PD; n=18] and adverse events [AEs; n=5]), and 1 pt was continuing treatment. After 17 cycles, 68 pts were eligible for maintenance treatment, of whom 46 received maintenance, and 15 were continuing maintenance treatment at the time of data cut-off. Median duration of follow-up was 22.3 months (95% confidence interval [CI]: 20.9–24.1). The 12-month PFS rate was 85.5% (95% CI: 76.2–91.3). The ORR was 87.4% (95% CI: 79.4–93.1); 64.1% of pts had a CMR. The 12-month OS rate was 91.9% (95% CI: 84.5–95.9); the 12-month DOR and DOCR rates were 89.6% (95% CI: 80.2–94.7) and 91.1% (95% CI: 79.4–96.2), respectively. Of the 46 pts who received maintenance, no pts experienced PD, and 1 pt died (reason unknown). Of the 22 pts who were eligible but did not receive maintenance, 1 pt had PD. The most common AEs (≥30%) were injection-site reaction (67.0%), fatigue (44.7%), cytokine release syndrome ([CRS] 34.0%), headache (32.0%), and nausea (32.0%). Grade (Gr) ≥3 AEs and serious AEs were reported in 47.6% and 35.9% of pts, respectively. Five pts experienced Gr 5 AEs: COVID-19 pneumonia (n=2) and cardiogenic shock, unexplained death, pneumonia (n=1 each). Infections occurred in 77.7% of pts and were predominantly Gr 1/2 (Gr 1: 10.7%; Gr 2: 47.6%; Gr 3: 12.6%; Gr 4: 3.9%), with the most common infection being COVID-19 (24.3%). Of 3 (2.9%) Gr 5 infections reported, 1 occurred during initial treatment (COVID-19), 1 during maintenance (pneumonia), and 1 occurred 2.8 months after completion of treatment (COVID-19). AEs were reported in 80.4% of pts in the maintenance phase, mostly Gr 1/2 events. No CRS events occurred during maintenance treatment. Infections were reported in 45.7% of pts during maintenance, with the majority being Gr 1/2 events (37.0%), and were similar types of infection as during initial therapy. ctDNA levels were assessed in a subset of pts who achieved a CMR; 86.4% (19/22) of pts were minimal residual disease (MRD) negative (p-value cut-off 0.005).Conclusions: Longer follow-up of mosunetuzumab SC with optional maintenance treatment continues to demonstrate promising PFS and OS rates, and a manageable safety profile in pts with previously untreated HTB FL. Exploratory analysis of ctDNA in a subset of CMR pts showed MRD negativity in 86.4%, thus supporting fixed treatment duration of mosunetuzumab SC. Overall, these data support the outpatient administration of mosunetuzumab SC in US community practices and further evaluation of mosunetuzumab-based treatment in first-line HTB FL.

Abstract Introduction: ASXL1-mutant (mt) Chronic Myelomonocytic Leukemia (CMML) is an aggressive myeloid neoplasm characterized by increased proliferation, resistance to epigenetic therapies, and poor survival. Epigenetic remodeling and up-regulation of leukemogenic driver genes are hallmarks of ASXL1mt CMML. Truncating mutations in ASXL1 activate enhancers that drive the expression of key leukemogenic driver genes such as HOXA9 and its co-factor MEIS1. Here, we investigate the chromatin accessibility of these leukemogenic enhancers by ASXL1 genotype at single-cell resolution (GoT-ChA-seq). Methods: After IRB approval, we performed bulk RNA-seq and ChIP-seq (H3K4me1, H3K4me3, H3K27ac, H3K27me3, H2AK119ub, H2BK20ac) on bone marrow (BM) mononuclear cells from 40 patients with CMML (19 ASXL1mt, 21 -wildtype/wt). After quality control, differential analyses of gene expression and histone modification occupancy between ASXL1mt and wt patients were conducted. A consensus peak calling framework was used to define genomic regions with ASXL1mt-specific histone modifications. Canonical enhancers were defined as genomic regions with a co-occupancy of H3K4me1 and H3K27ac. We then added regions marked by H2BK20ac to capture regulatory regions associated with p300 (Narita et al. Nat Genet 2023). We used an in silico prediction strategy to associate regulatory regions marked by strong histone modification occupancy with highly up-regulated leukemogenic driver genes (HOXA6-10, MEIS1). The ReMap database (Hammal et al. Nucleic Acids Res 2022) was queried for transcription factor binding in the genomic regions of interest. We then performed GoT-ChA-seq (Izzo et al. Nature 2024) to investigate chromatin accessibility for ASXL1mt (n=3) and wildtype BM single cells from CMML patients. In vitro colony forming assays were conducted on primary CMML BM cells (11- ASXL1mt and 9 wt CMML), assessing the efficacy of EP31670, a novel, oral, dual inhibitor of p300/BRD4. Results: This study included 40 patients with CMML, 19 ASXL1mt and 21 wt. The variant allele frequencies for ASXL1 were compatible with heterozygosity (median 0.41) and TET2 mutations were balanced between the two groups. We identified 149 candidate regulatory regions correlating with the expression of up-regulated target genes of interest (HOXA6-10, MEIS1) by bulk ChIP- and RNA-seq. Publicly available ChIP-seq data from myeloid cell lines demonstrated enrichment of p300 (in THP-1 cells, enrichment effect size +2.58, p=0.002) and BRD4 (in K-562 cells, enrichment effect size +1.58, p=0.045) in these candidate regulatory regions. Next, we interrogated the chromatin accessibility of ASXL1mt (n=13620) and ASXL1wt (n=24269) single cells from 3 CMML patients using GoT-ChA-seq. Differential accessibility analysis revealed 144 genomic regions, all of which were preferentially accessible in ASXL1mt cells compared to ASXL1wt cells (p<0.05 for all regions). Four of these preferentially accessible genomic regions (p<0.001 for all regions) overlapped with the previously identified candidate regulatory regions for MEIS1. The H3K27ac and H2BK20ac occupancy levels in these regions was strongly associated with the expression of MEIS1 (median Pearson r=0.73, p=1.16x10-7). These candidate regulatory regions were annotated in ENCODE as distal and proximal enhancers. Targeting this biology with the dual p300/BRD4 inhibitor EP31670 in progenitor colony forming assays led to a preferential therapeutic effect in ASXL1mt BM samples (median IC50 = 25nM) compared to in ASXL1wt samples (median IC50 = 74nM, p=0.03). Treatment with EP31670 was also associated with increased differentiation (increased blast forming units-erythroid; BFU-E) and organization of colonies in ASXL1mt vs wt CMML. Conclusions: ASXL1mt CMML is characterized by the up-regulation of several leukemogenic driver genes including HOXA9 and its co-factor MEIS1, secondary to the activation of genotype-specific enhancers. The preferential accessibility of these enhancers can be defined between ASXL1mt and ASXL1wt cells within patients. The enhancers of interest interact with p300 and BRD4 in myeloid cell lines and targeting them with the novel dual p300/BRD4 inhibitor, EP31670, induces therapeutic responses at low nanomolar drug concentrations in vitro, preferentially in ASXL1-mutant cells. These data solidify the biological rationale for targeting p300/BRD4 in ASXL1mt chronic myeloid neoplasms for therapeutic benefit (NCT05488548).

Abstract Background: Hypomethylating agent (HMA) with venetoclax (VEN) is used in clinical practice for frontline management of patients with myelodysplastic syndrome (MDS) based on encouraging data from phase 1 clinical trial (Garcia JS et al. Blood 2025). While the randomized clinical trial (VERONA-NCT04401748) did not show a survival benefit of azacitidine-VEN, the study had important differences such as exclusion of therapy related MDS and being conducted in several non-academic US centers. To better understand the impact of this regimen and its effects in subgroups, we conducted a real-world analysis of frontline MDS patients treated mainly at academic medical centers with HMA-VEN and compared to HMA monotherapy. Methods: This is a multicenter retrospective study of 19 US academic medical centers. We included contemporary cohorts of adults (age≥18 years) with MDS (intermediate, high or very high risk by IPSS-R) who were treated outside of clinical trials with either upfront combination of HMA-VEN or HMA monotherapy. Data on patient-related, disease-related and treatment-related variables were collected through chart review. Descriptive statistics were used for baseline characteristics. Overall survival (OS) and event free survival (EFS: progression, leukemic transformation, death as events) analysis was conducted using Kaplan-Meier method. Determinants of outcomes were analyzed using multivariable regression models. All analyses were conducted at a significance level of p<0.05. Results: Among 1198 patients with intermediate, high or very-high risk MDS, 313 patients received upfront VEN in combination with HMA [HMA-VEN] and 885 patients received HMA monotherapy. Median age was 70 (63-76) years and majority of patients had MDS with excess blasts-1 (34% overall, HMA-VEN=26%, HMA=37%) or MDS with excess-blasts-2 (41% overall, HMA-VEN=60%, HMA=34%). Disease risk by IPSS-R was intermediate (29% overall, HMA-VEN=18%, HMA=33%), high (30% overall, HMA-VEN=31%, HMA=30%) or very-high risk (41% overall, HMA-VEN=51%, HMA=37%, p<0.001). Therapy related MDS (t-MDS) was seen in 27% of patients (HMA-VEN=33%, HMA=25%, p=0.004), 34% had TP53 mutation (HMA-VEN=40%, HMA=32%, p=0.005) and 33% underwent allogeneic hematopoietic stem cell transplantation (AHSCT) (HMA-VEN=42%, HMA=30%, p<0.001). The most common mutations detected at baseline included TP53 (34%), ASXL1 (22%), DNMT3A (16%), RUNX1 (16%), TET2 (14%), SRSF2 (13%), and U2AF1 (11%). The response rate by IWG 2006 criteria was significantly higher with HMA-VEN than HMA monotherapy (overall 81% vs 39%, CR: 17% vs 9.6%; marrow CR: 56% vs 14%, p<0.001). In multivariable analysis accounting for upfront treatment, AHSCT, genomic mutations, baseline bone marrow blasts and t-MDS, patients treated with HMA-VEN in the upfront setting had significantly improved EFS (median EFS 10.7 vs. 7.8 mon, HR 0.83, 95%CI 0.72-0.96, p=0.01) and OS (median OS 22.4 vs. 18.1 mon, HR 0.79, 95%CI 0.64-0.97, p=0.02). In addition, TP53 mutation status (OS: HR 1.88, 95% CI 1.57-2.26, p<0.001, EFS: HR 1.43, 95% CI 1.23-1.65, p<0.001), subsequent AHSCT (OS: HR 0.34, 95% CI 0.27-0.41, p<0.001; EFS: HR 0.47, 95% CI 0.40-0.54, p<0.001), and therapy related MDS (OS: HR 1.20, 95% CI 1.00-1.44, p=0.04, EFS: HR 1.10, 95% CI 0.96-1.27, p=0.2) were significant predictors on multivariable analysis. When separately investigated in subgroups, an OS benefit of HMA-VEN over HMA was seen in patients undergoing subsequent AHSCT (median OS 40.6 vs. 30 mon, p=0.05), bone marrow blast 10-19% (median OS 25.1 vs. 17.4 mon, P=0.01), de novo MDS (median OS 30 vs. 20.1 mon, P=0.003) and absence of TP53 mutation (median OS 34.9 mon vs. 23.1 mon, p=0.004). The benefit of HMA-VEN over HMA was also seen across molecular mutations including presence of ASXL1 mutation (median OS 35.2 vs 20.9 mon, p=0.03). Conclusions: In this large multicenter retrospective analysis from US academic medical centers, we found that HMA-VEN therapy significantly improved OS in certain subsets of high risk MDS including patients with 10-19% blasts, denovo MDS, subsequent AHSCT and those without TP53 mutation. While our analysis is limited by its retrospective design, prospectively exploring subgroups of MDS patients who could benefit from HMA-VEN therapy is needed.