Abstract: Background: Thalidomide has marked activity in both untreated and heavily pretreated myeloma. Its activity in part is believed to be due to inhibition of bFGF and VEGF induced angiogenesis. Elevated levels of bFGF in serum and urine have correlated with decreased survival in lymphoma possibly through up-regulation of BCL-2. Methods: 25 patients (pts) with previously treated F-NHL and SLL were registered and treated on this multi-institutional study from July 2001–April 2004 to evaluate the efficacy and safety of oral thalidomide in this patient group. Pts had B-cell SLL (7: 36.8%), F-NHL grade 1 (7: 36.8%), grade 2 (3: 15.8%) and grade 3 (2: 10.1%) NHL. Pts were eligible for entry with up to 3 prior chemotherapy (CT) and 2 immunotherapy (IT) regimens provided performance status was ≥ 1. Pts with new onset of B-symptoms, rising LDH, rapid tumor growth or greater than one year from initial diagnosis were required to undergo repeat lymph node biopsy to exclude recent transformation. Pts with CNS involvement, prior peripheral neuropathy 〉 gr 1, HIV+, and pregnant or nursing women were also excluded. Pts were required to have Cr 〈 2 x ULN, AST/ALT 〈 2.5 x ULN and an ANC 〉 750. Median age at study entry was 60 years (36–87). Prior therapy was evaluated in 20 pts and 17/20 had received multi-agent CT while 12/20 pts received prior IT. Thalidomide was initiated at a dose of 200 mg daily and escalated by 100 mg daily every 1–2 weeks as tolerated with a maximal dose of 800 mg/d. If ≥ gr 2 peripheral neuropathy or ≥ gr 3 somnolence or mood changes occurred, the dose was held for one week and restarted at 50% of the prior daily dosage. Results: The median daily dose was 400 mg (range 50–800 mg). There was 1 complete response (CRu-residual abnormality) in a pt with SLL and one partial response in a pt with F-NHL grade 1 (ORR 8%: 95%CI: 1–26%). 16 pts had progressive disease during therapy and 2 died of disease soon after stopping therapy due to adverse events. One patient continues on therapy without progression of disease to date. The remaining 4 pts were taken off of therapy prior to the first 3 month evaluation. The reason for withdrawal was pt refusal (2) and adverse events (2). The median event free survival was 2.6 months (95% CI:1.4–4.4 mos) with a median overall survival of 23.3 months. Toxicity information on 24/25 pts revealed 4 (17%) with grade 4 neutropenia with 1/4 febrile as well. The most common grade 3 toxicities were anemia (13%), dyspnea (13%), fatigue (8%) and neurologic toxicities consisting of somnolence, dizziness, depression and anxiety (21%). Peripheral sensory neuropathy was reported as gr 2 in 8% and gr 3 in 8%. However, 38% of pts were reported as experiencing gr 2 fatigue. There were no grade 5 toxicities. Conclusion: These phase II trial results in a pretreated pt population demonstrate that, despite an acceptable toxicity profile, thalidomide has only minimal efficacy in F- NHL and SLL.

Abstract: Tumor necrosis factor (TNF) has marked effects on permeability and procoagulant activity on tumor-associated neovasculature when used in isolation perfusion, the latter effect primarily mediated via induction of cell surface expression of tissue factor (TF) on endothelial tissue. However, the cellular events that result in rapid alterations in endothelial cell (EC) permeability after intravascular TNF administration in isolation perfusion are not well characterized. We demonstrate that short exposure intervals to TNF induces TF expression on ECs but has no effect on permeability as assessed by flux of Evans blue–bound albumin across confluent EC monolayers using a 2-compartment model under basal culture conditions. However, a rapid and significant increase in EC permeability occurred with TNF in the presence of factor VIII–deficient plasma. Permeability was induced only with luminal versus abluminal TNF exposure and was blocked by antithrombin III, TF pathway inhibitor, or anti-TF antibody cotreatment. These data indicate that EC surface expression of TF and extrinsic clotting factors are critical in augmenting capillary leak following intravascular TNF administration. Alterations in permeability were associated with intercellular gap formation at sites of down-regulation of vascular endothelial (VE)–cadherin expression, the primary endothelial intercellular adhesion molecule, and intracellular contraction and alignment of F-actin cytoskeletal elements. Rapid induction of TF by TNF may be the primary EC response that results in alterations in permeability and procoagulant activity observed following intravascular TNF administration in isolation perfusion.

Abstract: The prognostic relevance of diagnosis to treatment interval (DTI) in patients with newly diagnosed mantle cell lymphoma (MCL) is unknown. Hence, we sought to evaluate the impact of DTI on outcomes in MCL using 3 large datasets (1) the University of Iowa/Mayo Clinic Specialized Program of Research Excellence Molecular Epidemiology Resource, (2) patients enrolled in the ALL Age Asthma Cohort/CALGB 50403, and (3) a multisitecohort of patients with MCL. Patients were a priori divided into 2 groups, 0 to 14 days (short DTI) and 15 to 60 days (long DTI). The patients in whom observation was deemed appropriate were excluded. One thousand ninety-seven patients newly diagnosed with MCL and available DTI were included in the study. The majority (73%) had long DTI (n=797). Patients with short DTI had worse eastern cooperative oncology group performance status (ECOG PS ≥2), higher lactate dehydrogenase, bone marrow involvement, more frequent B symptoms, higher MCL International Prognostic Index (MIPI ≥6.2), and were less likely to receive intensive induction therapy than long DTI group. The median progression-free survival (2.5 years vs 4.8 years, p & lt;0.0001) and overall survival (7.8 years vs. 11.8 years, p & lt;0.0001) were significantly inferior in the short DTI group than the long DTI cohort and remained significant for progression-free survival and overall survival in multivariable analysis. We show that the DTI is an important prognostic factor in patients newly diagnosed with MCL and is strongly associated with adverse clinical factors and poor outcomes. DTI should be reported in all the patients newly diagnosed with MCL who are enrolling in clinical trials and steps must be taken to ensure selection bias is avoided.

Abstract: Burkitt lymphoma (BL) accounts for most pediatric non-Hodgkin lymphomas, being less common but significantly more lethal when diagnosed in adults. Much of the knowledge of the genetics of BL thus far has originated from the study of pediatric BL (pBL), leaving its relationship to adult BL (aBL) and other adult lymphomas not fully explored. We sought to more thoroughly identify the somatic changes that underlie lymphomagenesis in aBL and any molecular features that associate with clinical disparities within and between pBL and aBL. Through comprehensive whole-genome sequencing of 230 BL and 295 diffuse large B-cell lymphoma (DLBCL) tumors, we identified additional significantly mutated genes, including more genetic features that associate with tumor Epstein-Barr virus status, and unraveled new distinct subgroupings within BL and DLBCL with 3 predominantly comprising BLs: DGG-BL (DDX3X, GNA13, and GNAI2), IC-BL (ID3 and CCND3), and Q53-BL (quiet TP53). Each BL subgroup is characterized by combinations of common driver and noncoding mutations caused by aberrant somatic hypermutation. The largest subgroups of BL cases, IC-BL and DGG-BL, are further characterized by distinct biological and gene expression differences. IC-BL and DGG-BL and their prototypical genetic features (ID3 and TP53) had significant associations with patient outcomes that were different among aBL and pBL cohorts. These findings highlight shared pathogenesis between aBL and pBL, and establish genetic subtypes within BL that serve to delineate tumors with distinct molecular features, providing a new framework for epidemiologic, diagnostic, and therapeutic strategies.

Abstract: Follicular lymphoma (FL) is clinically heterogeneous, with select patients tolerating extended watch-and-wait, whereas others require prompt treatment, suffer progression of disease within 24 months of treatment (POD24), and/or experience aggressive histologic transformation (t-FL). Because our understanding of the relationship between genetic alterations in FL and patient outcomes remains limited, we conducted a clinicogenomic analysis of 370 patients with FL or t-FL (from Cancer and Leukemia Group B/Alliance trials 50402/50701/50803, or real-world cohorts from Washington University School of Medicine, Cleveland Clinic, or University of Miami). FL subsets by grade, stage, watch-and-wait, or POD24 status did not differ by mutation burden, whereas mutation burden was significantly higher in relapsed/refractory (rel/ref) FL and t-FL than in newly diagnosed (dx) FL. Nonetheless, mutation burden in dx FL was not associated with frontline progression-free survival (PFS). CREBBP was the only gene more commonly mutated in FL than in t-FL yet mutated CREBBP was associated with shorter frontline PFS in FL. Mutations in 20 genes were more common in rel/ref FL or t-FL than in dx FL, including 6 significantly mutated genes (SMGs): STAT6, TP53, IGLL5, B2M, SOCS1, and MYD88. We defined a mutations associated with progression (MAP) signature as ≥2 mutations in these 7 genes (6 rel/ref FL or t-FL SMGs plus CREBBP). Patients with dx FL possessing a MAP signature had shorter frontline PFS, revealing a 7-gene set offering insight into FL progression risk potentially more generalizable than the m7–Follicular Lymphoma International Prognostic Index (m7-FLIPI), which had modest prognostic value in our cohort. Future studies are warranted to validate the poor prognosis associated with a MAP signature in dx FL, potentially facilitating novel trials specifically in this high-risk subset of patients.

Abstract: Systemic treatment for cutaneous T-cell lymphoma (CTCL) involves the use of less aggressive, well-tolerated therapies. Pralatrexate is a novel antifolate with high affinity for reduced folate carrier-1. A dose de-escalation strategy identified recommended pralatrexate dosing for patients with CTCL that demonstrated high activity, good rates of disease control, and an acceptable toxicity profile for continuous long-term dosing. Eligibility included mycosis fungoides, Sézary syndrome, or primary cutaneous anaplastic large cell lymphoma, with disease progression after ≥ 1 prior systemic therapy. The starting dose and schedule was 30 mg/m2/wk intravenously for 3 of 4 (3/4) weeks. Subsequent starting doses were 20, 15, and 10 mg/m2/wk for 3/4 or 2 of 3 (2/3) weeks. Response was evaluated by the modified severity-weighted adjustment tool. Fifty-four patients were treated. The recommended regimen was identified as 15 mg/m2/wk for 3/4 weeks and was explored in the expansion cohort. In 29 patients treated overall with the recommended dosing regimen, the median number of prior systemic therapies was 4. Pralatrexate was administered for a median of 4 cycles; response rate was 45%. The most common grade 3 adverse event (AE) was mucositis (17%); the only grade 4 AE was leukopenia (3%). Pralatrexate 15 mg/m2/wk for 3/4 weeks shows high activity with acceptable toxicity in patients with relapsed/refractory CTCL.

Abstract: Relapse following CD19-directed chimeric antigen receptor T-cells (CAR-T) for relapsed/refractory large B-cell lymphoma (r/r LBCL) is commonly ascribed to antigen loss or CAR-T exhaustion. Multi-antigen targeting and PD-1 blockade are rational approaches to prevent relapse. Here, we test CD19/22 dual-targeting CAR-T (AUTO3) plus pembrolizumab in r/r LBCL as inpatient or outpatient therapy (NCT03289455, https://clinicaltrials.gov/ct2/show/NCT03289455). Endpoints include toxicity (primary) and response rates (secondary). AUTO3 was manufactured for 62 patients using autologous leukapheresis, modified with a bicistronic transgene. 52 patients received AUTO3 (7/52,50x106; 45/52,150-450x106) and 48/52 received pembrolizumab. Median age was 59 years (range,27-83) and 46/52 had stage III/IV disease. Median follow-up was 21.6 months (range,15.1-51.3) at last data cut (Feb 28, 2022). AUTO3 was safe: grade 1-2 and grade 3 CRS affected 18/52 (34.6%) and 1/52 (1.9%) patients, neurotoxicity arose in 4 patients (2/4, grade 3-4), HLH affected 2 patients, and no Pembrolizumab-associated autoimmune sequalae were observed. On this basis, outpatient administration was tested in 20 patients, saving a median of 14 hospital days/patient. AUTO3 was effective: overall response rates were 66% (48.9%, CR; 17%, PR). For patients with CR, median DOR was not reached, with 54.4% (CI: 32.8, 71.7) projected to remain progression-free beyond 12 months after onset of remission. DOR for all responding patients was 8.3 months (95% CI: 3.0, NE) with 42.6% projected to remain progression-free beyond 12 months after onset of remission. Overall, AUTO3 +/- pembrolizumab for r/r LBCL was safe, lending itself to outpatient administration, and delivered durable remissions in 54.4% of complete responders, associated with robust CAR-T expansion. Neither dual-targeting CAR-T nor pembrolizumab prevented relapse in a significant proportion of patients, and future developments include next-generation-AUTO3, engineered for superior expansion/persistence in vivo, and selection of CAR binders active at low antigen densities.

Abstract: Introduction Ibrutinib was FDA approved for relapsed or refractory (R/R) marginal zone lymphoma (MZL) based on a phase II clinical trial that showed an overall response rate of 48% (Noy et al, Blood 2017). However, factors associated with response to ibrutinib in R/R MZL and outcomes of patients after progression on ibrutinib are unknown. Given the poor survival in other B-cell lymphomas such as mantle cell lymphoma (MCL) after progression on ibrutinib (Martin P et al, Blood 2016), we sought to evaluate clinicopathologic characteristics predictive of ibrutinib failure in R/R MZL, and describe outcomes of patients who experienced progression on ibrutinib therapy. Methods We performed a multicenter retrospective study of MZL patients treated at 19 US medical centers. Eligible patients were ≥ 18 years diagnosed with MZL from 2010-2019, who received ibrutinib for R/R MZL. Patients achieving a complete response (CR) or partial response (PR) with ibrutinib were considered ibrutinib responders, while those who had stable disease (SD) or progression of disease (PD) were classified as non-responders. The primary endpoint was to evaluate factors predictive of primary progression (PD) on ibrutinib. Secondary endpoints include evaluation of predictors of overall survival (OS) and progression-free survival (PFS) following ibrutinib therapy, assessment of outcomes based on the sequencing of ibrutinib therapy, and evaluation of outcomes following ibrutinib failure. PFS was defined as time from the start of ibrutinib therapy until lymphoma relapse/progression or death from any cause, censoring at last clinical assessment if no progression or death. OS was defined as time from the start of ibrutinib treatment until death or last follow-up. A multivariable Poisson regression analysis was performed to model ibrutinib progression on the clinicopathologic factors (see Table). To identify significant predictors for OS and PFS, we used a multivariable Cox model. Results 101 patients with R/R MZL received ibrutinib, of whom 99 had sufficient data for inclusion in the analysis. Among these patients, 63% (n=62) had CR/PR to ibrutinib (ibrutinib responders, CR=17, PR=45) and 37% (n=37) had no response (ibrutinib non-responders, SD=25, PD=12). The median duration of follow-up was 1.8 years (range=0.1-5.4 years) and 2 years (range=0.2-6.3 years) for ibrutinib responders and non-responders, respectively. Baseline characteristics of the R/R MZL patients stratified by ibrutinib response are shown in the Table. Among all the baseline factors examined for association with ibrutinib progression, only primary refractory disease (refractory to frontline therapy, RR=3.78, 95%CI=1.36-10.45, p=0.01) was predictive of a higher probability of primary progression on ibrutinib on multivariable analysis. The median OS was significantly better for responders (NR [not reached], 95%CI=3.2-NR) compared to non-responders (3.4 years, 95%CI=1.4-NR) (Figure 1A). Achieving CR/PR with ibrutinib (HR=0.22, 95%CI=0.09-0.52) and lack of complex cytogenetics (HR=0.22, 95%CI=0.08-0.59) were predictors of superior PFS. Similarly, ibrutinib response (HR=0.13, 95%CI=0.03-0.53) and lack of complex cytogenetics (HR=0.19, 95%CI=0.04-0.87) were predictors of better OS. There was no difference in PFS or OS based on the timing of ibrutinib administration (second vs third vs fourth line and beyond, Figure 1B and 1C). The median post ibrutinib relapse/progression OS (PROS) for patients who initially responded then progressed on ibrutinib (secondary progression, n=19) was 4 years (Figure 1D). The median PROS for patients who had no response to ibrutinib were stratified according to SD vs PD. The median PROS for those who had SD was NR and those with PD was 0.1 year (Figure 1E). Conclusion This is the largest series of R/R MZL patients treated with ibrutinib. A history of primary refractory disease was predictive of primary progression on ibrutinib, while the presence of complex cytogenetics was associated with inferior PFS and OS. In contrast to MCL, the outcomes of patients who progress on ibrutinib in R/R MZL are not poor except for the primary progression cohort (those with PD as the best response to ibrutinib). Improving therapeutic options for patients who experience PD with ibrutinib treatment represents an urgent unmet need and these patients should be prioritized for evaluation of novel therapeutic approaches. Figure Disclosures Epperla: Verastem Oncology: Speakers Bureau; Pharmacyclics: Honoraria. Reddy:Genentech, BMS: Research Funding; KITE Pharma, Abbvie, BMS, Celgene: Consultancy. Caimi:Genentech: Research Funding; Celgene Corp: Other: Incyte Corporation - Ownership - Pharmacyclics, Inc. - Ownership - Celgene Corp. - Other, Speakers Bureau; ADC Therapeutics: Research Funding. Greenwell:Lymphoma Research Foundation: Research Funding; Acrotech Biopharma LLC, Kyowa Kirin: Consultancy. Janakiram:Takeda, Fate, Nektar: Research Funding. Olszewski:Genentech, Inc.: Research Funding; Spectrum Pharmaceuticals: Research Funding; TG Therapeutics: Research Funding; Adaptive Biotechnologies: Research Funding. Cohen:Genentech, BMS, Novartis, LAM, BioInvent, LRF, ASH, Astra Zeneca, Seattle Genetics: Research Funding; Janssen, Adicet, Astra Zeneca, Genentech, Aptitude Health, Cellectar, Kite/Gilead, Loxo: Consultancy. Palmisiano:AbbVie: Research Funding; Genentech: Research Funding. Awan:Genentech: Consultancy; Janssen: Consultancy; Astrazeneca: Consultancy; Abbvie: Consultancy; Pharmacyclics: Consultancy; Gilead Sciences: Consultancy; Kite Pharma: Consultancy; Dava Oncology: Consultancy; Celgene: Consultancy; Blueprint medicines: Consultancy; Sunesis: Consultancy; Karyopharm: Consultancy; MEI Pharma: Consultancy. Barta:Monsanto: Consultancy; Atara: Honoraria; Seattle Genetics: Honoraria, Research Funding; Janssen: Honoraria; Pfizer: Honoraria. Grover:Genentech: Research Funding; Tessa: Consultancy. Bartlett:Roche/Genentech: Consultancy, Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Affimed Therapeutics: Research Funding; Acerta: Consultancy; BTG: Consultancy; Seattle Genetics: Consultancy, Research Funding; Pharmacyclics: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Millennium: Research Funding; Merck: Research Funding; Forty Seven: Research Funding; Immune Design: Research Funding; Janssen: Research Funding; Kite, a Gilead Company: Research Funding; ADC Therapeutics: Consultancy; Autolus: Research Funding; BMS/Celgene: Research Funding. Christian:Acerta: Research Funding; Celgene: Research Funding; Genentech: Research Funding; Merck: Research Funding; Millenium: Research Funding; MorphoSys: Research Funding; F Hoffman-La Roche: Research Funding; Triphase: Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Verastem: Membership on an entity's Board of Directors or advisory committees; AstraZenica: Membership on an entity's Board of Directors or advisory committees. Herrera:Pharmacyclics: Research Funding; Immune Design: Research Funding; AstraZeneca: Research Funding; Seattle Genetics: Consultancy, Research Funding; Gilead Sciences: Consultancy, Research Funding; Genentech, Inc./F. Hoffmann-La Roche Ltd: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Bristol Myers Squibb: Consultancy, Other: Travel, Accomodations, Expenses, Research Funding; Karyopharm: Consultancy.

Abstract: Background: MCL is an aggressive non-Hodgkin lymphoma (NHL) subtype and pts with progressive disease (PD) after BTKi therapy have a poor prognosis (Martin et al. Blood 2016). Glofitamab is a T-cell-engaging, CD20xCD3 bispecific antibody with a novel 2:1 molecular configuration with bivalency for CD20 on B cells and monovalency for CD3 on T cells. Glofitamab with obinutuzumab pretreatment (Gpt) has shown promising efficacy with frequent, durable complete responses (CR) and manageable tolerability with fixed dosing (NCT03075696; Dickinson et al. EHA 2020) and step-up dosing (SUD; Hutchings et al. J Clin Oncol 2021) in NHL. Glofitamab and obinutuzumab compete for binding to CD20 receptors; as a result, Gpt reduces the receptor occupancy (RO) of glofitamab. Pts with MCL have a 2-fold higher clearance of obinutuzumab vs other NHL histologies (Gibiansky et al. CPT Pharmacometrics Syst Pharmacol 2014), leading to lower obinutuzumab concentrations and higher glofitamab RO at the start of glofitamab treatment (Djebli et al . Blood 2020). A higher dose of Gpt prior to glofitamab SUD may therefore further reduce the risk of cytokine release syndrome (CRS) in MCL. We report preliminary data from the NP30179 Phase I/II trial in pts with R/R MCL who received a 1000mg or 2000mg dose of Gpt prior to glofitamab monotherapy. Methods: All pts received Gpt 7 days prior to the first glofitamab dose. Intravenous glofitamab SUD was given on days 1 and 8 of Cycle (C)1, then at the target dose from C2 day (D)1 (from C3D1 for SUD starting at 0.5mg), every 3 weeks for up to 12 cycles (0.5/2.5/10/30, 2.5/10/16 or 2.5/10/30mg after 1000mg Gpt, or 2.5/10/30mg after 2000mg Gpt). Pts on fixed dosing received glofitamab (0.6, 16 or 25mg) after 1000mg Gpt from C1 for up to 12 cycles. Response rates are based on the Lugano criteria (Cheson et al. J Clin Oncol 2014). Results: As of May 18, 2021, 29 pts had received glofitamab: fixed dosing after 1000mg Gpt (n=3); SUD after 1000mg Gpt (n=7; 1 pt received SUD starting at 0.5mg) or 2000mg Gpt (n=19). Median age was 69 years (range, 41-84; 69% male), 83% of pts had Ann Arbor Stage III-IV disease and 62.1% had MCL international prognostic index score ≥6 at study entry. Median prior lines of therapy was 3 (range, 1-6), 69% (n=20) had prior BTKi therapy and 14% (n=4) had prior lenalidomide therapy. Many pts were refractory to their first line of therapy (52%; n=15) and/or their last prior therapy (69%; n=20). Median time since last therapy was 1.7 months (range, 0.1-107.5). In efficacy-evaluable pts (n=21), the overall response rate was 81.0% (n=17) and complete metabolic response rate was 66.7% (n=14; Table 1). Similar response rates were observed in pts who had received prior BTKi therapy vs pts who had not (Table 2). Median duration of CR follow-up was 2.4 months (range, 0.0-25); 85.7% (12/14) pts with a CR remained in remission at the data cut-off (median duration of response and median duration of CR were not reached). In safety-evaluable pts (n=29), the most common adverse events (AEs) were CRS (58.6%) and infusion-related reactions (24.1%). All CRS events were Grade (Gr) 1-2 (by ASTCT criteria), except for 1 Gr 4 CRS in the 1000mg Gpt + SUD cohort (3.4%; pt died due to cardiopulmonary insufficiency as a result of rapid PD; at time of death CRS was persisting). CRS rates were lower in the 2000mg Gpt + SUD cohort (9/19; 47.4%) vs the 1000mg Gpt + SUD (5/7; 71.4%) and 1000mg Gpt + fixed dosing (3/3; 100%) cohorts. Overall, median time to first CRS event and duration of CRS event were 16.8 hrs and 38.8 hrs, respectively. All CRS events were manageable (tocilizumab used in 4 pts, low-flow oxygen in 2 pts) and most resolved at data cut-off. Neurologic AEs occurred in 6 pts (20.7%, all Gr 1 [n=5] or Gr 2 [n=1] ). Immune effector cell-associated neurotoxicity syndrome (ICANS)-like AEs occurred in 1 pt (3.4%): Gr 1 confusional state and Gr 2 ataxia, both resolving in 1 day. Tumor flare events occurred in 3 pts (10.3%, all Gr 1 [n=2] or Gr 2 [n=1] ). No pts discontinued treatment due to AEs. Three deaths were reported and considered unrelated to study treatment: PD (n=2); cardiac arrest (n=1). Conclusions: Glofitamab SUD as monotherapy after Gpt induced high response rates in pts with MCL, most of whom had failed prior BTKi therapy. CRS rates were manageable and mostly low grade. ICANS-like AEs were infrequent, low grade and resolved within 1 day. No treatment discontinuations due to AEs were observed. Further analyses will be presented. Figure 1 Figure 1. Disclosures Phillips: Genentech: Membership on an entity's Board of Directors or advisory committees, Research Funding; Bayer: Consultancy, Research Funding; ADCT, BeiGene, Bristol Myers Squibb, Cardinal Health, Incyte, Karyopharm, Morphosys, Pharmacyclics, Seattle Genetics: Consultancy; AbbVie: Consultancy, Research Funding; AstraZeneca: Consultancy; BMS: Consultancy, Research Funding; Incyte: Consultancy, Other: received travel expenses from Incyte, Research Funding. Dickinson: Celgene: Research Funding; Amgen: Honoraria; Janssen: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Takeda: Research Funding; MSD: Consultancy, Honoraria, Research Funding, Speakers Bureau; Gilead Sciences: Consultancy, Honoraria, Speakers Bureau; Roche: Consultancy, Honoraria, Other: travel, accommodation, expenses, Research Funding, Speakers Bureau; Novartis: Consultancy, Honoraria, Research Funding, Speakers Bureau. Morschhauser: Epizyme: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; AstraZenenca: Membership on an entity's Board of Directors or advisory committees; F. Hoffmann-La Roche Ltd: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees; Genmab: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees; Roche: Consultancy, Speakers Bureau; Chugai: Honoraria; Genentech, Inc.: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees; Servier: Consultancy. Bachy: Kite, a Gilead Company: Honoraria; Novartis: Honoraria; Daiishi: Research Funding; Roche: Consultancy; Takeda: Consultancy; Incyte: Consultancy. Crump: Kyte/Gilead: Membership on an entity's Board of Directors or advisory committees; Novartis: Membership on an entity's Board of Directors or advisory committees; Roche: Research Funding; Epizyme: Research Funding. Trněný: MorphoSys: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Portola: Honoraria, Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Honoraria; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; 1st Faculty of Medicine, Charles University, General Hospital in Prague: Current Employment; Celgene: Consultancy; Gilead Sciences: Consultancy, Honoraria, Other: Travel, Accommodations, Expenses; Incyte: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Roche: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Bristol-Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses; Amgen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel, Accommodations, Expenses. Bartlett: Washington University School of Medicine: Current Employment; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Affimed: Research Funding; Autolus: Research Funding; Bristol-Myers Squibb: Research Funding; Celgene: Research Funding; Forty Seven: Research Funding; Janssen: Research Funding; Kite Pharma: Research Funding; Merck: Research Funding; Millennium: Research Funding; Pharmacyclics: Research Funding; Genentech, Inc./F. Hoffmann-La Roche Ltd: Membership on an entity's Board of Directors or advisory committees, Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees, Research Funding. Zaucha: Takeda: Honoraria, Research Funding; BMS: Honoraria, Research Funding; Roche: Honoraria; Amgen: Honoraria; AbbVie: Honoraria; Janssen: Honoraria. Humphrey: Roche: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Perez-Callejo: F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company. Lundberg: F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company. Relf: Roche Pharmaceutical Ltd: Current Employment, Current equity holder in publicly-traded company; F-Star Therapeutics: Current equity holder in publicly-traded company, Divested equity in a private or publicly-traded company in the past 24 months; Harpoon Therapeutics: Divested equity in a private or publicly-traded company in the past 24 months. Filézac de L'Étang: F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company. Carlile: AstraZeneca: Current equity holder in publicly-traded company, Ended employment in the past 24 months; F. Hoffmann-La Roche Ltd: Current Employment, Current equity holder in publicly-traded company. Clark: Roche Products Ltd: Current Employment. Carlo-Stella: Sanofi: Consultancy, Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding; AstraZeneca: Honoraria; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm Therapeutics: Membership on an entity's Board of Directors or advisory committees; Incyte: Honoraria; Janssen Oncology: Honoraria; Celgene: Membership on an entity's Board of Directors or advisory committees. OffLabel Disclosure: Glofitamab is a full-length, humanized, immunoglobulin G1 bispecific antibody with a 2:1 molecular format that facilitates bivalent binding to CD20 on B-cells, and monovalent binding to CD3 on T-cells. Glofitamab redirects T cells to engage and eliminate malignant B cells. Glofitamab is an investigational agent.