Search

Over the past decade, our understanding of AML pathogenesis and pathophysiology has improved significantly with mutational profiling. This has led to translational advances in therapeutic options, as there have been 10 new US Food and Drug Administration (FDA) approvals for AML therapies since 2017, half of which target specific driver mutations in FLT3, IDH1, or IDH2. These new agents have expanded the therapeutic armamentarium for AML, particularly for patients who are considered ineligible for intensive chemotherapy with anthracycline- and cytarabine-containing regimens. These new treatment options are relevant because the median age at diagnosis is 68 years, and outcomes for patients older than 60 years have historically been dismal. However, the optimal approach to incorporating novel agents into frontline regimens remains a clinical challenge, particularly with regard to sequencing of therapies, considering the role of allogeneic hematopoietic stem cell transplantation and managing toxicities.

KMT2A-rearranged (KMT2A-R) B cell acute lymphoblastic leukemia (ALL) is a high-risk disease in children and adults that is often chemotherapy resistant. To identify non-cytotoxic approaches to therapy, we performed a domain-specific kinome-wide CRISPR screen in KMT2A-R cell lines and patient derived xenograft samples (PDX) and identified dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A) as a potential target. Pharmacologic inhibition of the KMT2A-fusion transcriptional co-regulator Menin released the KMT2A-fusion complex from the DYRK1A promoter thereby lowering DYRK1A expression levels confirming DYRK1A as a direct target of the KMT2A fusion oncogene. Direct pharmacologic inhibition of DYRK1A decreased cell proliferation of KMT2A-R ALL, thereby confirming the requirement of DYRK1A in this ALL subtype. To further understand the biologic function of DYRK1A in KMT2A-R ALL, we leveraged pharmacologic DYRK1A inhibitors in KMT2A-R PDX and cell line models. DYRK1A inhibition consistently led to upregulation of MYC protein levels, and hyperphosphorylation of ERK, which we confirmed via in vivo treatment experiments. Furthermore, DYRK1A inhibition decreased ALL burden in mice. Our results further demonstrate that DYRK1A inhibition induces the proapoptotic factor BIM, but ERK hyperphosphorylation is the driving event that induces cell cycle arrest. In contrast, combined treatment of KMT2A-R ALL cells in vitro and in vivo with DYRK1A inhibitors and the BCL2 inhibitor, venetoclax, synergistically decreases cell survival and reduced the leukemic burden in mice. Taken together these results demonstrate a unique function of DYRK1A specially in KMT2A-R ALL. Synergistic inhibition of DRYK1A and BCL2 may provide a low-toxic approach to treat this high risk ALL subtype.

Most patients receiving CAR T-cell therapy (CAR-T) for aggressive B-cell lymphoma (B-NHL) will not experience a durable remission. There are several novel agents approved for the treatment relapsed, refractory aggressive B-NHL; however, it remains unclear how to sequence these therapies pre- and post-CAR-T (peri-CAR-T). We conducted a multicenter retrospective analysis for the purpose of describing peri-CAR-T practice patterns and survival predictors for patients receiving CD19-directed CAR-T. Patients (n=514) from thirteen centers treated with CAR-T for aggressive B-NHL between 2015-2021 were included. Clinical characteristics, CAR-T outcomes and treatment regimens administered pre- and post-CAR-T were collected. Survival curves were constructed using Kaplan Meier method. Multivariate Cox regression was used to determine the impact of variables on survival outcomes. For all patients receiving CAR-T, a greater number lines of therapy prior to CAR-T apheresis and receipt of bridging therapy were predictive of inferior progression-free survival (PFS) and overall survival (OS). From time of CAR-T infusion, median PFS and OS were 7.6 and 25.6 months (n=514). From time of progression post-CAR-T (n=254), median OS was 5.5 months. The median PFS of treatments given in the first-line post-CAR-T failure (n=167) was just 2.8 months. Patients with refractory disease at day 30 had inferior OS and were less likely to receive subsequent treatment(s) compared to other patients with CAR-T failure. AlloHCT for select patients at any time following CAR-T failure (n=16) led to durable responses in over half at one-year. These data provide a benchmark for future clinical trials in patients with progression post-CAR-T, an unmet clinical need.

Non-Hodgkin lymphomas (NHL) are cancers of mature B-, T-, and NK-cells which display marked biological heterogeneity between different subtypes. Mature T- and NK-cell neoplasms are an often-aggressive subgroup of NHL and make up approximately 15% of all NHL. Long-term follow up studies have demonstrated that patients with relapsed/refractory disease have dismal outcomes; in particular, secondary central nervous system (CNS) involvement is associated with higher mortality, though it remains controversial whether this independently confers worse outcomes or if it simply reflects more aggressive systemic disease. Possible risk factors predictive of CNS involvement, such as an elevated lactate dehydrogenase and more than two sites of extranodal involvement, may suggest the latter, though several studies have suggested that discrete sites of anatomic involvement or tumor histology may be independent risk factors as well. Ultimately, small retrospective case series form the basis of our understanding of this rare but devastating event but have not yet demonstrated a consistent benefit of CNS-directed prophylaxis in preventing this outcome. Nonetheless, ongoing efforts are working to establish the epidemiology of CNS progression/relapse in mature T- and NK-cell lymphomas with the goal of identifying clinicopathologic risk factors, which may potentially help discern which patients may benefit from CNS-directed prophylactic therapy or more aggressive systemic therapy.

Dual-specificity tyrosine phosphorylation-regulated kinase 1 A (DYRK1A) is a serine/threonine kinase that belongs to the DYRK family of proteins, a subgroup of the evolutionarily conserved CMGC protein kinase superfamily. Due to its localization on chromosome 21, the biological significance of DYRK1A was initially characterized in the pathogenesis of Down syndrome (DS) and related neurodegenerative diseases. However, increasing evidence has demonstrated a prominent role in cancer through its ability to regulate biologic processes including cell cycle progression, DNA damage repair, transcription, ubiquitination, tyrosine kinase activity, and cancer stem cell maintenance. DYRK1A has been identified as both an oncogene and tumor suppressor in different models, underscoring the importance of cellular context in its function. Here, we review mechanistic contributions of DYRK1A to cancer biology and its role as a potential therapeutic target.

Introduction The treatment of aggressive B-cell NHL has evolved rapidly over the last 5 years, owing to the FDA approval of 3 CD19 CAR T-cell constructs (CARTs) along with other novel targeted therapies. Real world practice data suggest that CARTs have been successfully administered in populations typically excluded from clinical trials. However, data on how to best utilize novel targeted agents as a pathway to CARTs and feasibility of CARTs in rare histologies remains limited. This retrospective multicenter study describes patient (pt) selection and practice patterns in pts treated with CD19 CARTs and provides insight on feasibility of CARTs in special populations. Methods Adult pts with R/R aggressive B-cell NHL treated with CD19 CARTs between 2015- 2020 across 12 US academic centers were identified. Data on demographic and clinical characteristics, disease and toxicity outcomes were collected. Univariate analyses (UVA) were performed to determine impact of demographic/clinical variables on survival. Survival curves were calculated using Kaplan-Meier method. Subgroup analysis was performed for pts with secondary central nervous system lymphoma (sCNSL). Results Clinical and demographic features were recorded from 400 pts (Table 1). Median age was 59 years (range 18-84). Of 271 pts with immunohistochemistry data, 79 (29%) had double-expressor lymphoma. Of 178 pts with FISH data captured, 62 (35%) had double/triple-hit lymphoma. Most common histological subtypes included 271 (68%) pts with de novo DLBCL, 81 (20%) with transformed FL, 13 (3%) with Richter's syndrome, and 8 (2%) with PMBCL. Rare histologies included 7 (2%) with transformed MZL, 5 (1%) with PTLD and 2 (0.5%) with grey zone lymphoma. 24 (6%) pts had sCNSL at time of CART apheresis. Two (0.5%) pts were HIV-positive. Median number of lines of therapy prior to CART was 2 (range 1-8); 182 (46%) pts received ≥ 3 lines. 114 (28%) pts previously had an autologous stem cell transplant. Targeted therapies used as salvage regimens at any point prior to CART are listed in Table 2: commonly used salvage targeted therapies included lenalidomide based therapy (imids, n=37, 9%), BTK inhibitors (BTKis, n=30, 8%), checkpoint inhibitors (CBIs, n=17, 4%) and polatuzumab-containing regimens (n=10, 3%). 2 (1%) pts received loncastuximab, and no pts received tafasitamab. Six (1.5%) pts proceeded to CART despite complete response to most recent pre-CART therapy. 191 (48%) pts received bridging between apheresis and CART infusion, choice of bridging noted in Table 2: the majority received chemotherapy (n=103, 54%); 28 (15%) received radiation (XRT); 25 (13%), 24 (13%) and 18 (9%) pts received imids, polatuzumab-containing regimens, or BTKis, respectively. With median follow-up of 22.4 months (mo) for the overall group, median (m) PFS was 11 mo (n=363); mOS, was 27 mo (n=397; Fig 1). Pts with sCNSL had a mPFS and mOS of 2 and 4 mo, respectively (Fig 1). On UVA, factors predicting poorer PFS and OS in the overall group included ≥3 pre-CART lines (p For outcomes according to bridging regimens: mPFS after CART for most commonly used systemic bridging therapies was 86 days (d) for platinum-based chemotherapy, 77 d for imids, 90 d for BTKis, 98 d for polatuzumab-bendamustine/rituximab, and 274 d for XRT. Median PFS for XRT bridging (274 d) was statistically better when compared to mPFS for listed systemic therapies combined (p Conclusion Survival outcomes with CARTs in our data set are consistent with those reported in clinical trial settings. CARTs are utilized in real world practice in rare subsets of aggressive R/R B-cell NHL not routinely included in clinical trials. Despite early data suggesting pts with sCNSL benefit from CART, our data suggest outcomes with CART are dismal in this group. Targeted therapies including imids, polatuzumab, BTKis and CBIs are feasible choices for salvage and/or bridging as a pathway to CARTs. Bridging with XRT resulted in improved mPFS post CART as compared to bridging with systemic therapies and suggests differences in pt selection for each with systemic therapies likely favored in those with more widespread disease burden. Minimal use of CD19-targeted agents pre-CART is attributed to later approval of these agents and concern for potential loss of CD19 antigen leading to CART resistance. Figure 1 Figure 1. Disclosures Cohen: Janssen, Adicet, Astra Zeneca, Genentech, Aptitude Health, Cellectar, Kite/Gilead, Loxo, BeiGene, Adaptive: Consultancy; Genentech, BMS/Celgene, LAM, BioINvent, LOXO, Astra Zeneca, Novartis, M2Gen, Takeda: Research Funding. Shouse: Kite Pharma: Speakers Bureau; Beigene: Honoraria. Hess: ADC Therapeutics: Consultancy; BMS: Speakers Bureau. Stephens: Beigene: Membership on an entity's Board of Directors or advisory committees; Novartis: Research Funding; Epizyme: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Adaptive: Membership on an entity's Board of Directors or advisory committees; Arqule: Research Funding; Mingsight: Research Funding; JUNO: Research Funding; Celgene: Consultancy; CSL Behring: Consultancy; AstraZeneca: Consultancy; Abbvie: Consultancy; Innate Pharma: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Research Funding. Ma: Loxo: Research Funding; AstraZeneca: Honoraria, Research Funding, Speakers Bureau; Juno: Research Funding; Beigene: Research Funding, Speakers Bureau; Abbvie: Honoraria, Research Funding; Janssen: Research Funding, Speakers Bureau; TG Therapeutics: Research Funding; Pharmacyclics: Research Funding, Speakers Bureau. Winter: BMS: Other: Husband: Data and Safety Monitoring Board; Actinium Pharma: Consultancy; Janssen: Other: Husband: Consultancy; Gilead: Other: Husband: Consultancy; Agios: Other: Husband: Consultancy; Epizyme: Other: Husband: Data and Safety Monitoring Board; Merck: Consultancy, Honoraria, Research Funding; Novartis: Other: Husband: Consultancy, Data and Safety Monitoring Board; Ariad/Takeda: Other: Husband: Data and Safety Monitoring Board; Karyopharm (Curio Science): Honoraria. Gordon: Zylem Biosciences: Patents & Royalties: Patents, No royalties; Bristol Myers Squibb: Honoraria, Research Funding. Danilov: Astra Zeneca: Consultancy, Honoraria, Research Funding; Genentech: Consultancy, Honoraria, Research Funding; Takeda Oncology: Research Funding; TG Therapeutics: Consultancy, Research Funding; Abbvie: Consultancy, Honoraria; Beigene: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria; Gilead Sciences: Research Funding; Bristol-Meyers-Squibb: Honoraria, Research Funding; Rigel Pharm: Honoraria; Bayer Oncology: Consultancy, Honoraria, Research Funding; SecuraBio: Research Funding. Shah: Umoja: Consultancy; Legend: Consultancy; Kite: Consultancy; Miltenyi Biotec: Consultancy, Honoraria, Research Funding; Lily: Consultancy, Honoraria, Research Funding; Epizyme: Consultancy; Incyte: Consultancy. Barta: Seagen: Honoraria; Daiichi Sankyo: Honoraria; Acrotech: Honoraria; Kyowa Kirin: Honoraria. Epperla: Genzyme: Honoraria; Karyopharm: Other: Ad Board; Beigene: Speakers Bureau; Verastem: Speakers Bureau. Torka: TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Karmali: Epizyme: Consultancy; BeiGene: Consultancy, Speakers Bureau; EUSA: Consultancy; Roche: Consultancy; AstraZeneca: Speakers Bureau; Morphosys: Consultancy, Speakers Bureau; Karyopharm: Consultancy; Takeda: Research Funding; BMS/Celgene/Juno: Consultancy, Research Funding; Janssen/Pharmacyclics: Consultancy; Genentech: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding, Speakers Bureau.

Background: KMT2A-rearranged (R) ALL is a high-risk disease with a frequency of 75% in infants and 10% in children and adults with ALL and is associated with chemoresistance, relapse, and poor survival. Current intensive multiagent chemotherapy regimens induce significant side effects, yet fail to cure many patients, demonstrating continued need for novel therapeutic approaches. We performed a kinome-wide CRISPR screen and identified that DYRK1A is specifically required for the survival of KMT2A-R ALL cell. DYRK1A is a member of the dual-specificity tyrosine phosphorylation-regulated kinase family and has been reported as negatively regulator of cell proliferation. Results: We performed a kinome-wide CRISPR screen in human ALL cell lines and PDX models and identified DYRK1A as a novel target in KMT2A-R ALL. DYRK1A is a serine-threonine kinase with a proposed, but poorly defined role in cell cycle regulation. We performed a meta-analysis of multiple ChIP-Seq experiments and identified that oncogenic KMT2A fusions directly bind to the DYRK1A promoter. Our RT-PCR and Western blot analyses of KMT2A-R ALL cells treated with a menin inhibitor (MI-503) to disrupt the transcriptional activity of the KMT2A-R complex resulted in the downregulation of DYRK1A, indicating that DYRK1A is directly regulated by the KMT2A fusion complex. We further observed that pharmacologic inhibition of DYRK1A with EHT1610 induced potent leukemic cell growth inhibition in vitro and in vivo, demonstrating that DYRK1A could be a new therapeutic target in KMT2A-R ALL cells. To further elucidate the mechanism of DYRK1A function, we treated several KMT2A-R ALL cell lines in vitro with EHT1610, which surprisingly resulted in the upregulation of MYC and hyperphosphorylation of the RAS/MAPK target ERK. Given that ERK hyperactivation stops B cell proliferation during early B cell development to allow them to rearrange their B cell receptor, we hypothesized that cell cycle inhibition upon ERK hyperactivation remains as a conserved mechanism of cell cycle regulation in KMT2A-R ALL. Strikingly, combining DYRK1A inhibition with the MEK inhibitor trametinib antagonistically rescued KMT2A-R ALL cell proliferation, indicating that ERK hyperactivation is the main driver of DYRK1A inhibitor mediated cell cycle arrest. Given that DYRK1A inhibitor does not induce apoptosis and cells restart cell proliferation after EHT1610 withdrawal we concluded that a DYRK1A monotherapy may not be an ideal new treatment option. However, it has been reported that increased MYC activity induces the accumulation of BIM in Burkitt's Lymphoma. Given the increased expression of MYC following DYRK1A inhibition we performed a new Western blot analysis and validated increased expression of BIM in our KMT2A-R ALL cell lines after EHT1610 treatment. To test if targeting the interaction of BIM with BCL2 will induce an apoptotic effect when combined with EHT1610, we treated four KMT2A-R ALL cell lines with increasing concentrations of EHT1610 and the BCL2 inhibitor venetoclax. Strikingly, the combination of DYRK1A inhibition with BCL2 inhibition synergistically killed KMT2A-R ALL cells. Conclusion: Our results validate DYRK1A as an important molecule to regulate cell proliferation via inhibition of MYC and ERK. Targeting DYRK1A results in the accumulation of BIM, which renders the cells sensitive to BCL2 inhibition via venetoclax. While further in vivo studies are needed, we predict that combining DYRK1A inhibition with venetoclax may be a novel precision medicine strategy for the treatment of KMT2A-R ALL. Figure 1 Figure 1. Disclosures Crispino: Forma Therapeutics: Research Funding; Scholar Rock: Research Funding; MPN Research Foundation: Membership on an entity's Board of Directors or advisory committees; Sierra Oncology: Consultancy. Tasian: Aleta Biotherapeutics: Consultancy; Gilead Sciences: Research Funding; Kura Oncology: Consultancy; Incyte Corporation: Research Funding. Carroll: Incyte Pharmaceuticals: Research Funding; Janssen Pharmaceutical: Consultancy.

Introduction Central nervous system (CNS) relapse (CNSr) in patients with aggressive non-Hodgkin lymphoma (NHL) occurs uncommonly (estimated incidence 5%) but carries a high morbidity and mortality. Studies have identified risk factors for CNSr such as high tumor burden and extranodal (EN) disease. However, most focus on B-cell NHL with minimal data in T-cell lymphomas (TCL), which are significantly less common and more heterogenous. The few small series of CNSr in TCL report a median overall survival (OS) less than 3 months (mo) with incidence ranging from 2.6-9%. To better define CNSr in TCL, we performed a multi-institutional retrospective analysis of TCL patients with CNSr and herein describe clinicopathologic characteristics and treatment of CNSr. Methods We performed a retrospective observational study using data from 9 US academic centers with IRB approval at individual sites. We included adult patients diagnosed with a mature T-cell neoplasm as per the 2016 WHO classification between 1/1/2009-1/1/2019, who were found to have CNSr at any time after initial diagnosis, and collected patient, disease, and treatment characteristics at time of initial diagnosis as well as at CNSr. Patients with a diagnosis of a precursor T-cell malignancy or with CNS disease identified at initial TCL diagnosis (TCLd) and/or prior to first-line systemic treatment were excluded. Results In this analysis, we report the outcomes of 75 patients (male n=45, female n=30). At TCLd, the median age was 59 years (range 20-81), and 61% of patients (n=46) had an IPI score of at least 3, 92% (n=69) had EN involvement with 37% (n=28) involving at least 2 EN sites, and 59% (n=44) had BM involvement. The most common pathologic diagnoses were peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS; 24%, n=18), angioimmunoblastic T-cell lymphoma (AITL; 17%, n=13), adult T-cell leukemia/lymphoma (ATLL; 17%, n=13), and mycosis fungoides (MF; 12%, n=9) (Figure 1A). First-line systemic therapy for TCL included anthracyclines for 72% (n=54). Autologous and allogenic transplants were performed prior to CNSr in 12% (n=9) and 8% (n=6) of patients, respectively. Prior to CNSr, 48% (n=36) had non-CNS relapse. Some form of CNS prophylaxis was used during initial systemic lymphoma therapy in 24% of patients (n=18), predominantly intrathecal methotrexate (IT MTX; n=16). Median time from TCLd to CNSr was 8.5mo, though this was significantly longer in MF (46.8mo [range 17.5-187.7]) versus PTCL, NOS (7.6mo [range 1.1-58.4], P=0.0002), AITL (21.2mo [range 2.0-61.6, P=0.008), and ATLL (7.3mo [range 0.7-46.4], P=0.0005) (Figure 1B). CNSr developed within 6mo of TCLd in 31% of patients (n=23) and within 12mo in 57% (n=43). Symptoms related to CNSr occurred in 71% of patients (n=53). CNSr patterns were 61% leptomeningeal (n=46), 21% parenchymal (n=16), and 17% both (n=13) with no significant survival difference between leptomeningeal or parenchymal disease alone (HR 1.45, 95% CI 0.78-2.70, P=0.28). Concomitant systemic relapse was observed in 59% of patients (n=44). The most common CNS-directed therapy for CNSr was IT MTX (56%; n=42), though multiple different IT and/or systemic regimens were used. Patients received a median of 1 line of CNS-directed treatment (range 0-5). The overall response rate to initial CNS directed treatment was 32% (16% CR, 16% PR). Median follow up after CNSr was 40.7mo. At last follow up, 83% had died (n=62). Median OS after CNSr was 4.6mo (range 0.1-68.7) (Figure 1C). Those with ATLL had the shortest median OS after CNSr (2.7mo) versus 6.3mo in MF (HR 3.69, 95% CI 1.44-9.42, P=0.005), 6.5mo in AITL (HR 2.16, 95% CI 0.92-5.06, P=0.054), and 4.8mo in PTCL, NOS (HR 1.49, 95% CI 0.70-3.19, P=0.27) (Figure 1D). The most common cause of death was progressive lymphoma (77%; n=48). Conclusions This is to our knowledge the largest series of CNSr in TCL to date. Most CNSr occurred within 12mo, though CNSr occurred later in patients with MF. Although the prognosis after CNSr was generally poor, we found that median OS in CNSr was longer than previously reported, perhaps reflecting more effective treatments for CNS and systemic relapse, inclusion of MF, or lead time bias. Further analysis of the impact of different treatment strategies and outcomes in CNSr was limited by the small sample size and heterogeneity within our cohort, and future analyses in a larger cohort should focus on factors associated with outcomes. Figure 1 Figure 1. Disclosures Horwitz: ADC Therapeutics, Affimed, Aileron, Celgene, Daiichi Sankyo, Forty Seven, Inc., Kyowa Hakko Kirin, Millennium /Takeda, Seattle Genetics, Trillium Therapeutics, and Verastem/SecuraBio.: Consultancy, Research Funding; Affimed: Research Funding; Aileron: Research Funding; Acrotech Biopharma, Affimed, ADC Therapeutics, Astex, Merck, Portola Pharma, C4 Therapeutics, Celgene, Janssen, Kura Oncology, Kyowa Hakko Kirin, Myeloid Therapeutics, ONO Pharmaceuticals, Seattle Genetics, Shoreline Biosciences, Inc, Takeda, Trillium Th: Consultancy; Celgene: Research Funding; C4 Therapeutics: Consultancy; Crispr Therapeutics: Research Funding; Daiichi Sankyo: Research Funding; Forty Seven, Inc.: Research Funding; Kura Oncology: Consultancy; Kyowa Hakko Kirin: Consultancy, Research Funding; Millennium/Takeda: Research Funding; Myeloid Therapeutics: Consultancy; ONO Pharmaceuticals: Consultancy; Seattle Genetics: Consultancy, Research Funding; Secura Bio: Consultancy; Shoreline Biosciences, Inc.: Consultancy; Takeda: Consultancy; Trillium Therapeutics: Consultancy, Research Funding; Tubulis: Consultancy; Verastem/Securabio: Research Funding. Bennani: Purdue Pharma: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Vividion: Other: Advisory Board; Kymera: Other: Advisory Board; Verastem: Other: Advisory Board. Chavez: AstraZeneca: Research Funding; ADC Therapeutics: Consultancy, Research Funding; Merk: Research Funding; MorphoSys, AstraZeneca, BeiGene, Genentech, Kite, a Gilead Company, and Epizyme: Speakers Bureau; MorphoSys, Bayer, Karyopharm, Kite, a Gilead Company, Novartis, Janssen, AbbVie, TeneoBio, and Pfizer: Consultancy; BMS: Speakers Bureau. Sokol: Dren Bio: Membership on an entity's Board of Directors or advisory committees; Kyowa-Kirin: Membership on an entity's Board of Directors or advisory committees. Saeed: Nektar Therapeutics: Consultancy, Other: research investigator; MEI Pharma Inc: Consultancy, Other: investigator; Celgene Corporation: Consultancy, Other: investigator; MorphoSys AG: Consultancy, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb Company: Consultancy; sano-aventis U.S.: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen Pharmaceutica Products, LP: Consultancy, Other: investigator; Kite Pharma: Consultancy, Other: investigator; Other-TG therapeutics: Consultancy, Other: investigator; Other-Epizyme, Inc.: Consultancy; Other-Secura Bio, Inc.: Consultancy; Seattle Genetics, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees. Mehta-Shah: Kiowa Hakko Kirin: Consultancy; C4 Therapeutics: Consultancy; Verastem: Research Funding; Karyopharm: Consultancy; Ono Pharmaceuticals: Consultancy; Secura Bio: Consultancy, Research Funding; Daiichi Sankyo: Consultancy, Research Funding; AstraZeneca: Research Funding; Bristol Myers Squibb: Research Funding; Celgene: Research Funding; Innate Pharmaceuticals: Research Funding; Roche/Genentech: Research Funding; Corvus Pharmaceuticals: Research Funding. Olszewski: TG Therapeutics: Research Funding; PrecisionBio: Research Funding; Celldex Therapeutics: Research Funding; Acrotech Pharma: Research Funding; Genentech, Inc.: Research Funding; Genmab: Research Funding. Allen: Epizyme: Consultancy; MorphoSys: Consultancy; ADC Therapeutics: Consultancy; Secure Bio: Consultancy; Kyowa Kirin: Consultancy. Gerson: Abbvie: Consultancy; Kite: Consultancy; TG Therapeutics: Consultancy; Pharmacyclics: Consultancy. Landsburg: Triphase: Research Funding; Takeda: Research Funding; Curis: Research Funding; ADCT: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Other: DSMB member; Incyte: Membership on an entity's Board of Directors or advisory committees; Morphosys: Membership on an entity's Board of Directors or advisory committees. Schuster: Adaptive Biotechnologies: Research Funding; Pharmacyclics: Research Funding; Merck: Research Funding; Genentech/Roche: Consultancy, Research Funding; Tessa Theraputics: Consultancy; Juno Theraputics: Consultancy, Research Funding; Loxo Oncology: Consultancy; BeiGene: Consultancy; Alimera Sciences: Consultancy; Acerta Pharma/AstraZeneca: Consultancy; Abbvie: Consultancy, Research Funding; Nordic Nanovector: Consultancy; Novartis: Consultancy, Honoraria, Patents & Royalties, Research Funding; Incyte: Research Funding; TG Theraputics: Research Funding; Celgene: Consultancy, Honoraria, Research Funding. Svoboda: Atara: Consultancy; Adaptive: Consultancy, Research Funding; Astra Zeneca: Consultancy, Research Funding; Imbrium: Consultancy; Pharmacyclics: Consultancy, Research Funding; Genmab: Consultancy; Merck: Research Funding; Incyte: Research Funding; BMS: Consultancy, Research Funding; TG: Research Funding; Seattle Genetics: Consultancy, Research Funding. Barta: Kyowa Kirin: Honoraria; Acrotech: Honoraria; Daiichi Sankyo: Honoraria; Seagen: Honoraria.

Background: Anti-CD19 chimeric antigen receptor T-cell therapy (CART) is a highly active therapy for relapsed/refractory (R/R) aggressive B-cell lymphoma. Nonetheless, most patients (pts) ultimately develop progressive disease (PD). There is little guidance on the optimal treatment approach(es) for these pts. We performed a multicenter retrospective analysis with a primary objective to assess treatment patterns and outcomes in pts with R/R aggressive B-cell lymphoma who develop PD after anti-CD19 CARTs. Methods: Pts with aggressive B-cell lymphoma treated with anti-CD19 CART between 2015 and 2020 across 12 US academic medical centers were included. Demographic and clinical characteristics were collected along with CART toxicities and response. Regimens administered as salvage post CART were assessed. Univariate analyses (UVA) were performed to determine impact of demographic and clinical variables on survival outcomes. All p-values were two-tailed. Survival curves were calculated using the Kaplan-Meier method. Results: A total of 400 pts received anti-CD19 CARTs and were included for analysis. For the entire cohort: median PFS and OS from time of CART infusion were 11 months [mo] and 27 mo respectively. On log-rank testing, pts who received ≥3 lines of pre-CART therapy and those with refractory disease pre-CART had significantly worse PFS (p=0.004 & 0.001) and OS (both p With median follow-up 22.4 mo, 190 pts (48%) had PD after CART; demographic and clinical variables of pts with and without PD are detailed in Table 1. Biopsy to confirm PD and assess CD19 status was done in 69 pts (36%) with CD19 negative relapse seen in 11 (16%). Of pts with PD, median PFS and OS from time of PD was 83 days (in pts who received salvage) and 174 days (for all PD pts) respectively. Pts with PD were more likely to have elevated LDH (p=0.001) and extranodal disease (p=0.003) at apheresis. For pts with PD after CART: 125 (65.5%) received further therapies. Pts were more likely to receive salvage therapies if their best response to CART was CR (p=0.026) or PR (p=0.015). Response rates of select first- and second-line therapies and PFS of first line therapies received after CART failure are detailed in figure 1. ORR and CRs were highest for polatuzumab, bendamustine, & rituximab (pola-BR; 73% & 40%), followed by BTK inhibitors (BTKi; 50% & 38%), and bispecific antibodies (bsAb) (50% & 25%). Five of 7 pts who received a BTKi had non-germinal center (GC) cell of origin (COO; 1 unknown COO). On log-rank testing, pts with elevated LDH (p=0.003) at time of apheresis and those with intermediate/high IPI (p=0.013) had inferior PFS with first salvage regimens. Median PFS was highest for pola-BR (4.5 mo, n=14), followed by bsAb (2.5 mo, n=8), lenalidomide +/- anti-CD20 antibody (1.8 mo, n=13), checkpoint inhibitors (CPI; 1.6 mo, n=10), BTKi (1.2 mo, n=8), radiation alone (1.2 mo; n=17), chemotherapy (1.1 mo, n=12), and tafasitamab + lenalidomide (0.9 mo, n=5). Median PFS for all treated pts was 1.8 mo. OS from start of first salvage regimen was highest for CPI (OS 12.4 mo, n=10), followed by pola-BR (8.9 mo, n=14), BTKi (8.8 mo, n=8), lenalidomide +/- anti-CD20 (8.7 mo, n=13), radiation alone (7.1 mo, n =17), bsAb (5.9 mo, n=8), chemotherapy (5.4 mo, n=12), and tafasitamab + lenalidomide (1.2 mo, n=5). 12 pts (6.3%) later received an allogeneic hematopoietic cell transplant (alloHCT). In alloHCT pts at last follow-up, 10 were evaluable for response: 7 had CR and 5 remain in CR. Clinical characteristics of pts who received alloHCT are detailed in table 2. Notably, median age was 59 years (41-68), 1 (8.3%) had a prior alloHCT, and 6 (50%) had prior autologous HCT. The majority had CR or PR as best response to CART (CR n=6, 50%; PR n=3, 25%), and only 1 pt (8.3%) with PD as best response to CART was salvaged with alloHCT. Conclusions: This is the largest reported analysis to date of pts with aggressive B-cell lymphoma who develop PD post-CART. The highest ORRs were with pola-BR, bsAb, and BTKi as first line of salvage. High response rates with BTKi may be attributed to non-GC COO in the majority of treated pts and perhaps a beneficial immunomodulatory effect on previously administered CARTs. AlloHCT remains a potential curative therapy for select pts with over half with durable remission; however, few ultimately received alloHCT. Despite increased use of novel therapies, survival in pts who progress after CART is still dismal warranting more effective therapies. Figure 1 Figure 1. Disclosures Epperla: Genzyme: Honoraria; Karyopharm: Other: Ad Board; Beigene: Speakers Bureau; Verastem: Speakers Bureau. Torka: TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Hess: ADC Therapeutics: Consultancy; BMS: Speakers Bureau. Cohen: Janssen, Adicet, Astra Zeneca, Genentech, Aptitude Health, Cellectar, Kite/Gilead, Loxo, BeiGene, Adaptive: Consultancy; Genentech, BMS/Celgene, LAM, BioINvent, LOXO, Astra Zeneca, Novartis, M2Gen, Takeda: Research Funding. Ma: Abbvie: Honoraria, Research Funding; Beigene: Research Funding, Speakers Bureau; Loxo: Research Funding; Juno: Research Funding; AstraZeneca: Honoraria, Research Funding, Speakers Bureau; Janssen: Research Funding, Speakers Bureau; TG Therapeutics: Research Funding; Pharmacyclics: Research Funding, Speakers Bureau. Winter: Gilead: Other: Husband: Consultancy; Janssen: Other: Husband: Consultancy; Ariad/Takeda: Other: Husband: Data and Safety Monitoring Board; Epizyme: Other: Husband: Data and Safety Monitoring Board; Agios: Other: Husband: Consultancy; Actinium Pharma: Consultancy; BMS: Other: Husband: Data and Safety Monitoring Board; Merck: Consultancy, Honoraria, Research Funding; Novartis: Other: Husband: Consultancy, Data and Safety Monitoring Board; Karyopharm (Curio Science): Honoraria. Gordon: Zylem Biosciences: Patents & Royalties: Patents, No royalties; Bristol Myers Squibb: Honoraria, Research Funding. Danilov: Bayer Oncology: Consultancy, Honoraria, Research Funding; Genentech: Consultancy, Honoraria, Research Funding; Rigel Pharm: Honoraria; Takeda Oncology: Research Funding; TG Therapeutics: Consultancy, Research Funding; Abbvie: Consultancy, Honoraria; Beigene: Consultancy, Honoraria; Pharmacyclics: Consultancy, Honoraria; SecuraBio: Research Funding; Astra Zeneca: Consultancy, Honoraria, Research Funding; Bristol-Meyers-Squibb: Honoraria, Research Funding; Gilead Sciences: Research Funding. Stephens: Adaptive: Membership on an entity's Board of Directors or advisory committees; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Beigene: Membership on an entity's Board of Directors or advisory committees; Epizyme: Membership on an entity's Board of Directors or advisory committees; JUNO: Research Funding; Mingsight: Research Funding; CSL Behring: Consultancy; Novartis: Research Funding; Abbvie: Consultancy; AstraZeneca: Consultancy; Arqule: Research Funding; Celgene: Consultancy; Innate Pharma: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees, Research Funding. Shah: Miltenyi Biotec: Consultancy, Honoraria, Research Funding; Umoja: Consultancy; Incyte: Consultancy; Kite: Consultancy; Legend: Consultancy; Epizyme: Consultancy; Lily: Consultancy, Honoraria, Research Funding. Shouse: Beigene Pharmaceuticals: Honoraria; Kite Pharmaceuticals: Speakers Bureau. Barta: Acrotech: Honoraria; Daiichi Sankyo: Honoraria; Seagen: Honoraria; Kyowa Kirin: Honoraria. Karmali: Karyopharm: Consultancy; EUSA: Consultancy; Roche: Consultancy; Janssen/Pharmacyclics: Consultancy; Genentech: Consultancy; Morphosys: Consultancy, Speakers Bureau; Epizyme: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding, Speakers Bureau; BMS/Celgene/Juno: Consultancy, Research Funding; AstraZeneca: Speakers Bureau; Takeda: Research Funding; BeiGene: Consultancy, Speakers Bureau.