Citations

Abstract Clinical significance of somatic gene variants needs to be comprehensively characterized for their diagnostic, prognostic and/or therapeutic actionability in patient management. However, challenges remain due to discrepancies in interpretation and reporting of these somatic variants among different testing labs. Therefore, standardized curation, clinical interpretation and reporting of somatic variants in hematologic cancers is critical. To address this issue, the Hematologic Cancer Taskforce (HCT), composed of 52 multi-disciplinary experts including oncologists, molecular pathologists, lab directors, genomic scientists and biocurators, was formed in January 2020 within the ClinGen Somatic Cancer Clinical Domain Working Group (CDWG) with a goal to undertake systematic curation and evidence-based clinical interpretation of genes/somatic variants associated with hematologic malignancies. In collaboration with the Clinical Interpretation of Variants in Cancer (CIViC) (civicdb.org) knowledgebase, HCT members curate, edit, and verify Evidence Items for each variant extracted from peer-reviewed publications. Monthly discussions based on these Evidence Items lead to the preparation of variant Assertions, which summarize the state of the field consensus variant interpretation and include tiering based on the AMP/ASCO/CAP guidelines (PMID: 27993330). FMS-like tyrosine kinase 3 (FLT3) encodes a class III receptor tyrosine kinase expressed in hematopoietic cells. FLT3 mutations, including both internal tandem duplication (ITD) and mutations in the tyrosine kinase domain (TKD), are the most common mutations in acute myeloid leukemia (AML), occurring in approximately 30% of all AML cases. Implementing FLT3 tyrosine kinase inhibitors (TKIs) in different treatment regimens for FLT3 mutated AML patients has led to significantly improved overall survival. Type I FLT3 inhibitors, including midostaurin, gilteritinib, sunitinib, lestaurtinib, and crenolanib, bind to the ATP-binding site when the receptor is in active conformation. Type II FLT3 inhibitors, including sorafenib, ponatinib, and quizartinib, interact with a hydrophobic region directly adjacent to the ATP-binding domain that is only accessible when the receptor is inactive, which prevents receptor activation. Generally in AML cells, type I FLT3 inhibitors prevent activity for both ITD and TKD mutations, while Type II inhibitors target ITD but lack efficiency against TKD mutations. The development of TKD mutations in AML cells with ITD have proved to be a mechanism of acquired, or secondary resistance to Type II FLT3 inhibitors. The HCT is piloting curation assessments of FLT3 alterations, including ITD, TKD and non-TKD variants, in AML. So far, the HCT has curated 75 evidence items for FLT3 somatic variants. FLT3-ITD, as well as D835 and I836 were asserted as tier 1 level A variants based on the prediction of response to gilteritinib in relapsed/refractory AML (PMIDs: 27993330, 31665578, 28645776, 28516360, 27908881). Recent curation activities are focused on FLT3 D839G and N676K, as clinical trials using large AML patient cohorts are lacking in their ability to validate drug response/resistance associations of these two TKD variants due to their low frequency. Functional studies showed both variants result in increased proliferation and protection from apoptosis, supporting the oncogenic potential of these two variants (PMIDs: 26891877, 2468088). FLT3 D839G combined with ITD confers resistance to pexidartinib and ponatinib, both Type II FLT3 inhibitors (PMIDs: 25847190, 23430109). FLT3 N676K predicts response to the Type I FLT3 inhibitor, gilteritinib, when N676K is present alone or in combination with ITD. Interestingly, FLT3 N676K in the absence of ITD predicts response to sorafenib, a Type II FLT3 inhibitor (PMIDs: 32040554, 32984009). However, these results are mostly derived from in vitro studies. Two separate Tier II, Level D Assertions have been submitted for FLT3-ITD&D839G for its response to pexidartinib and ponatinib, and more evidence is being collected to form an Assertion for FLT3 N676K. The complexity of the prediction of response/resistance associated with FLT3 D839G and N676K supports the importance of evidence-based curation and collection for these variants in the context of the overall mutation profile, disease context and specific FLT3 TKIs to clearly define their clinical impact. Disclosures Pullarkat: Stemline Therapeutics: Honoraria.

Abstract Background: Diffuse large B-cell lymphoma (DLBCL) is frequently curable after frontline therapy, however, relapses can occur after achievement of a PET-negative complete remission (CR). Early detection of relapse may be associated with improved outcomes, particularly given the development of more active therapies for relapsed, refractory DLBCL. Controversy exists regarding the utility of post-therapy surveillance imaging which is associated with patient (pt) anxiety, radiation exposure, false-positive results, and cost, without clear overall survival benefit in retrospective studies (Thompson JCO 2014). A retrospective study found that serial minimal residual disease (MRD) monitoring during DLBCL surveillance could identify pts at risk of relapse before clinical evidence of disease (Roschewski Lancet Oncol 2015). In this multicenter prospective study, we assessed whether a next-generation immunosequencing (IS) MRD assay could be used for early detection of molecular relapse in DLBCL. Methods: Eligible pts with DLBCL or high-grade B-cell lymphoma (HGBCL) who received anthracycline-containing chemotherapy were enrolled across five cancer centers. In pts who achieved a PET-negative CR, serial peripheral blood samples were obtained every 3 months (mos) and CT scans every 6 mos for 2 years (yrs) post-treatment. The IS MRD assay (Adaptive Biotechnologies, Seattle, WA) that leverages multiplex PCR followed by NGS to identify and track rearrangements of IgH, V-J, D-J and IgK/L loci and translocations in Bcl1/2-IgH was used. MRD positive was defined as any detectable rearrangement and MRD undetectable as no evidence of rearrangement. Results: 500 pts were enrolled and 400 were evaluable (pre-treatment tumor pathology available, completed frontline treatment, and achieved PET-negative CR at end-of-treatment). Baseline characteristics were median age of 62 yrs (range 19-95), male sex 58%, advanced stage 61%, and poor-risk by R-IPI 42%. Histologies included DLBCL, NOS (88%), primary mediastinal B-cell lymphoma (6%), HGBCL (5%), T-cell rich B-cell lymphoma (3%), and other (1%). Pts received regimens including RCHOP x 6 cycles (37%), REPOCH x 6 cycles (20%), clinical trial (15%), combined modality therapy (RCHOP+RT) (9%), and other RCHOP variations (19%). Among the 400 evaluable pts, 44 relapses have occurred as of July 1, 2021. In 45% of pts (20/44), clinical relapse was detected using surveillance imaging alone (typically CT CAP with IV contrast) in an otherwise asymptomatic pt with a normal physical exam and laboratory evaluation . In 10% of pts (4/44), relapse was detected by patient-reported clinical symptoms alone. In 45% of pts (20/44), relapse was detected by imaging, clinical symptoms, and/or evaluation by an oncologist. With a median follow-up of 34 months, the 2-year PFS was 88.9% (85.8, 92.1). Advanced age, advanced stage, and poor-risk R-IPI were associated with inferior PFS. Of the 44 relapses, tumor-specific clonotypes were identified in 39 pts (4 failed quality control (QC), 1 failed calibration) and 38 pts had ≥1 sample available within 90 days of relapse. Of 356 patients in ongoing CR, tumor-specific clonotypes were identified in 279 patients (29 failed QC, 33 failed calibration, and 15 are pending sequencing). The patient-level prospective MRD results are shown in Figure 1. The overall sensitivity, specificity, positive predictive value, and negative predictive value of the IS MRD assay was 63% (24/38), 78% (218/279), 28% (24/85), and 94% (218/232), respectively. Plasma MRD detection had improved sensitivity and specificity compared with circulating cells. Among the 24 relapsed patients with a positive MRD result at or before relapse, the median anticipation of the test was 3 months (range 0 to 24 months). Conclusion: Overall outcomes are excellent for DLBCL and HGBCL pts who achieve PET-negative CR. In this multicenter prospective analysis with standardized follow up, a substantial proportion (45%) of clinical relapses are detected radiographically in asymptomatic pts, supporting the value of CT surveillance imaging in DLBCL, particularly for pts with advanced stage or high-risk disease. MRD assessment using the IS MRD assay had suboptimal sensitivity and specificity in the post-treatment surveillance setting in DLBCL. Further study of the clinical context and its correlation with test performance is ongoing. Figure 1 Figure 1. Disclosures Kumar: Kite Pharmaceuticals: Other: advisory board , Research Funding; Abbvie Pharmaceuticals: Research Funding; Celgene: Honoraria, Other: advisory board, Research Funding; Adaptive Biotechnologies, Celgene, Abbvie Pharmaceticals, Pharmacyclics, Seattle Genetics: Research Funding; Pharmacyclics: Research Funding; Astra Zeneca: Honoraria, Other: Advisory Board, Research Funding; Seattle Genetics: Research Funding. Westin: Novartis: Consultancy, Research Funding; Genentech: Consultancy, Research Funding; Curis: Research Funding; Morphosys: Research Funding; ADC Therapeutics: Consultancy, Research Funding; Iksuda Therapeutics: Consultancy; Umoja: Consultancy; MorphoSys: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; AstraZeneca: Consultancy, Research Funding; Bristol Myers Squibb: Consultancy, Research Funding; 47 Inc: Research Funding. Schuster: TG Theraputics: Research Funding; Incyte: Research Funding; Adaptive Biotechnologies: Research Funding; Pharmacyclics: Research Funding; Merck: Research Funding; Genentech/Roche: Consultancy, Research Funding; Tessa Theraputics: Consultancy; Loxo Oncology: Consultancy; Juno Theraputics: Consultancy, Research Funding; BeiGene: Consultancy; Alimera Sciences: Consultancy; Acerta Pharma/AstraZeneca: Consultancy; Novartis: Consultancy, Honoraria, Patents & Royalties, Research Funding; Abbvie: Consultancy, Research Funding; Nordic Nanovector: Consultancy; Celgene: Consultancy, Honoraria, Research Funding. Nowakowski: Celgene, NanoString Technologies, MorphoSys: Research Funding; Celgene, MorphoSys, Genentech, Selvita, Debiopharm Group, Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees. Lossos: Lymphoma Research Foundation: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Consultancy; Janssen: Consultancy, Honoraria; NCI: Research Funding; University of Miami: Current Employment; NIH grants: Research Funding; Stanford University: Patents & Royalties; Verastem: Consultancy, Honoraria. Jacob: Adaptive Biotechnologies: Current Employment. Mullins: Adaptive Biotechnologies: Current Employment. Zelenetz: AstraZeneca: Honoraria; Amgen: Honoraria; Beigene: Honoraria, Other, Research Funding; Gilead: Honoraria, Research Funding; SecuraBio: Honoraria; Genentech/Roche: Honoraria, Research Funding; BMS/Celgene/JUNO: Honoraria, Other; Janssen: Honoraria; LFR: Other; MEI Pharma: Honoraria, Research Funding; Abbvie: Honoraria, Research Funding; Verastem: Honoraria; MethylGene: Research Funding; NCCN: Other; Pharmacyclics: Honoraria; Novartis: Honoraria; Gilead: Honoraria; MorphoSys: Honoraria.

Abstract Purpose: Axicabtagene ciloleucel (axi-cel) is an anti-CD19 chimeric antigen receptor T-cell (CAR-T) therapy utilized for patients with non-Hodgkin lymphoma (NHL) refractory to at least 2 lines of therapy. F-18 fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) is used to evaluate disease extent prior to CAR-T infusion at two time points: pre-leukapheresis (pre-leuk) approximately 6 weeks prior to CAR-T infusion, and pre-lymphodepletion chemotherapy (pre-LD) approximately 1 week prior to CAR-T infusion. We hypothesized that PET/CT characteristics beyond Lugano criteria, such as metabolic tumor volume (MTV), total lesion glycolysis (TLG), SUV maximum (SUVMax), and changes in these parameters from pre-leuk to pre-LD, may predict for progressive disease (PD), death, and treatment toxicity after CAR-T infusion. Methods: Patients with NHL who received axi-cel on a prospective registry at Mayo Clinic Rochester were included. Lesions on pre-leuk and pre-LD PET/CT scans were segmented with a fixed absolute SUVMax threshold of 2.5 using a semi-automated workflow (LesionID, MIM Software Inc.) with manual modification to exclude physiologic uptake as needed. MTV, TLG, SUVMax, number of lesions, and other lesion characteristics were assessed for each PET/CT, and changes from pre-leuk to pre-LD were calculated. Lesions were categorized as either nodal, spleen, bone, parenchymal (i.e. liver, lung), or soft tissue (i.e. subcutaneous, muscle), and MTV was calculated for each category. Univariate Cox modeling was used to associate relative and directional change in metabolic and volumetric PET/CT characteristics with PD and death, after adjusting for bridging therapy. LASSO method was used for multivariable model selection. Pre-LD PET/CT characteristics were also assessed for association with presence and duration of cytokine release syndrome (CRS), grade 3+ immune effector cell-associated neurotoxicity syndrome (ICANS), tocilizumab (toci) use, and corticosteroid use. Results: From 2018-2020, axi-cel was delivered to 69 patients. Histology included diffuse large B-cell lymphoma (57%), transformed follicular lymphoma (23%), or high-grade lymphoma (19%). Pre-leuk and pre-LD PET/CT scans were performed a median of 46 days and 7 days prior to CAR-T infusion, respectively. Forty patients (58%) received bridging therapy between scans, including 9 (13%) receiving radiotherapy. At a median follow-up of 13 months, 39 (57%) had died and 46 (67%) had PD. Sixty patients (87%) developed CRS following CAR-T infusion for a median duration of 5 days. Presence of pre-LD parenchymal disease was associated with longer duration CRS (p=0.032). Thirty-seven patients (54%) developed ICANS for a median duration of 4.5 days, including 12 (32%) with grade 3+ ICANS. Greater pre-LD total MTV was associated with higher risk of grade 3+ ICANS (p=0.042). Greater pre-LD SUVMax was associated with longer duration ICANS (p=0.032). Nineteen (28%) patients required toci. Greater pre-LD total MTV, SUVMax, TLG, and volume of the largest lesion were associated with increased use of toci (p<0.05 for all). Greater pre-LD total MTV and TLG of the largest lesion were associated with increased use of corticosteroid (p<0.05 for each). While no individual pre-leuk or pre-LD PET/CT characteristics were associated with risk of PD or death, increases from pre-leuk to pre-LD in total MTV, total TLG, parenchymal MTV, and nodal MTV were associated with increased risk of PD (Figure 1). Similarly, increases from pre-leuk to pre-LD in parenchymal MTV, nodal MTV, TLG of the largest lesion, and total number of lesions were associated with increased risk of death (p<0.05 for all). LASSO analysis identified increasing extranodal MTV (≥25% increase) and increasing TLG of the largest lesion (≥10% increase) as strong predictors of death (AUC 0.74, Table 1). Kaplan-Meier plots were generated for overall and progression-free survival using these risk factors (Figure 2). Additional patients and follow-up will be presented. Conclusions: Patients with greater pre-LD MTV had higher risk of grade 3+ ICANS and use of toci or corticosteroids. Increasing metabolic disease burden during CAR-T manufacturing is associated with increased risk of PD and death. A two variable risk score using increasing extranodal disease and increasing TLG of the largest lesion may stratify prognosis prior to CAR-T and inform treatment paradigms. Figure 1 Figure 1. Disclosures Bennani: Verastem: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Kyowa Kirin: Other: Advisory Board; Vividion: Other: Advisory Board; Kymera: Other: Advisory Board. Paludo: Karyopharm: Research Funding. Wang: Genentech: Research Funding; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; InnoCare: Research Funding; Novartis: Research Funding; MorphoSys: Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Lin: Gamida Cell: Consultancy; Janssen: Consultancy, Research Funding; Legend: Consultancy; Novartis: Consultancy; Celgene: Consultancy, Research Funding; Sorrento: Consultancy; Bluebird Bio: Consultancy, Research Funding; Takeda: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Merck: Research Funding; Vineti: Consultancy; Juno: Consultancy.

Abstract Introduction: Up to 40% of newly diagnosed diffuse large B cell lymphoma (DLBCL) will relapse after frontline rituximab, doxorubicin, cyclophosphamide, vincristine, and prednisone (RCHOP), with subsequent poor prognosis. Identification of patients (pts) at high risk of relapse early in the treatment can allow for development of risk adapted therapies to improve outcomes. Positron Emission Tomography scan after 2 cycles of therapy (PET2) has been evaluated as a predictor of relapse but study treatments were heterogenous and results were conflicting. A substudy of CALGB 50303 trial did not find association of PET2 response by Deauville Score (DS) with survival in RCHOP and DA-EPOCH-R treated pts. In the UK National Cancer Research Institute Prospective Study, DS of 5 on PET2 predicted worse progression free survival but not overall survival (OS) in RCHOP-21 and RCHOP-14 treated pts. Here we report impact of PET2 response on outcomes in two large independent, prospective cohorts of newly diagnosed DLBCL treated homogenously with two RCHOP-based regimens of similar efficacy. Methods: Discovery was done in adult pts with DLBCL enrolled into a single arm phase 2 trial of lenalidomide plus standard RCHOP (R2CHOP) (MC078E, NCT00670358). The validation cohort comprised of adult pts with newly diagnosed DLBCL treated with standard RCHOP prospectively enrolled into the Mayo component of the University of Iowa/Mayo Clinic Molecular Epidemiology Resource (MER). Both MC078E and MER cohorts included patients who received at least 3-6 cycles of therapy and had a PET2. Pts who progressed on PET2 were excluded. End of treatment (EOT) PET was done 3-12 weeks after last cycle of therapy. The revised response criteria for malignant lymphoma (Cheson, et al 2007) was used to assess PET in MC078E. In MER, revised response criteria for malignant lymphoma (Cheson et al 2007) or Lugano classification was used, depending on era of diagnosis. Positive PET was defined as FDG uptake above background (Cheson 2007) or DS 4 or 5 (Lugano 2014). Study endpoints were event-free survival (EFS) and OS by PET2 status. Results: Out of 118 pts treated on MC078E, 102 had PET2 (MC078E). The median age at diagnosis was 64 years (range 19-87), 61 (60%) were male, 89 (87%) had advanced stage disease, 46 (45%) had international prognostic index (IPI) of 3-5. 58 (57%) were PET2 Negative (PET2-ve) and 44 (43%) were PET2 Positive (PET2+ve). At EOT PET, 83 (81%) had -ve PET and 15 (15%) had +ve PET. Out of 44 PET2+ve pts, 15 remained +ve at EOT PET. Out of 58 PET2-ve pts, 56 had EOT PET available and all were -ve. Out of 866 DLBCL pts enrolled into MER between August 2005 and June 2015, 621 were treated with RCHOP for 3-6 cycles and 272 had available PET2 (MER). The median age was 65 years (range 55-73), 152 (56%) were male, 174 (64%) had advanced stage, 103 (38%) had IPI 3-5. 186 (68%) were PET2-ve and 86 (32%) were PET2+ve. Out of 235 with EOT PET available, 182 (77%) had -ve EOT PET and 25 (11%) had +ve EOT PET. PET2+ve pts had higher odds of +ve EOT PET (OR: 17.4 (CI 95 8.3-40.0), p<0.001) and progression on EOT PET (OR: 4.3 (CI 95 1.9-10.2), p<0.001) in MER cohort. This analysis was not possible on MC078E as all PET2-ve had -ve EOT PET. In MC078E, 2-year EFS and OS were 69.5% (CI 95 61.1-79.1) and 88.1% (CI 95 82-94.7). In MER, 2-year EFS and OS were 71.6% (CI 95 67.7-76.8) and 82.3% (CI 95 79.3-85.3). Compared to PET2-ve, PET2+ve pts had significantly inferior EFS in both MC078E (HR 4.0, CI 95 2.1-7.88, p<0.0001, figure 1a) and MER (HR 2.9, CI 95 1.9-4.1, p<0.0001, figure 1c). Compared to PET2-ve , PET2+ve pts had a trend towards lower OS in MC078E (HR 2.0, CI 95 0.9-4.9, p=0.1, figure 1b) and a significantly lower OS in MER (HR 2.3, CI 95: 1.5-3.4, p<0.0001, figure 1d). In subgroup analysis of MC078E, PET2+ve pts had lower EFS and a trend towards lower OS in all subgroups except IPI 0-2 (Table 1). In MER, PET2+ve pts had lower EFS and OS in all the subgroups except stage I-II and IPI 0-2 (Table 1). Conclusions: Positive PET2 was associated with increased risk of disease progression and death in newly diagnosed DLBCL. Results of our study provide robust evidence of importance of PET2 as an early predictor DLBCL pts at high risk of progression in two independent prospective cohorts. PET2-guided risk-adapted strategies using chimeric antigen receptor T-cell therapy and bispecific antibodies may potentially improve outcomes, should be explored in clinical trials and results of our study serve as a benchmark for such studies. Figure 1 Figure 1. Disclosures Maurer: Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Genentech: Research Funding; Morphosys: Membership on an entity's Board of Directors or advisory committees, Research Funding; Nanostring: Research Funding; Celgene: Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees. Wang: Genentech: Research Funding; Eli Lilly: Membership on an entity's Board of Directors or advisory committees; Novartis: Research Funding; MorphoSys: Research Funding; InnoCare: Research Funding; Incyte: Membership on an entity's Board of Directors or advisory committees, Research Funding; LOXO Oncology: Membership on an entity's Board of Directors or advisory committees, Research Funding; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees. Cerhan: Celgene/BMS: Other: Connect Lymphoma Scientific Steering Committee, Research Funding; Regeneron Genetics Center: Other: Research Collaboration; NanoString: Research Funding; Genentech: Research Funding. Ansell: Bristol Myers Squibb, ADC Therapeutics, Seattle Genetics, Regeneron, Affimed, AI Therapeutics, Pfizer, Trillium and Takeda: Research Funding. Habermann: Seagen: Other: Data Monitoring Committee; Incyte: Other: Scientific Advisory Board; Tess Therapeutics: Other: Data Monitoring Committee; Morphosys: Other: Scientific Advisory Board; Loxo Oncology: Other: Scientific Advisory Board; Eli Lilly & Co.,: Other: Scientific Advisor. Witzig: Celgene/BMS, Acerta Pharma, Kura Oncology, Acrotech Biopharma, Karyopharm Therapeutics: Research Funding; Karyopharm Therapeutics, Celgene/BMS, Incyte, Epizyme: Consultancy, Membership on an entity's Board of Directors or advisory committees. Nowakowski: Celgene, NanoString Technologies, MorphoSys: Research Funding; Celgene, MorphoSys, Genentech, Selvita, Debiopharm Group, Kite/Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees.

Abstract Introduction: Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 Chimeric Antigen Receptor (CAR) T-cell therapy that induces durable responses in patients with relapsed or refractory large B-cell lymphoma. At a median of 27.1 months follow-up on the ZUMA-1 trial, median overall survival (OS) was 25.8 months with 39% progression free survival (PFS) at 2 years post-infusion (Locke, Lancet Onc 2019). We previously reported outcomes of axi-cel patients treated with standard of care therapy at a median follow up of 12.9 months, including 42% who did not meet eligibility criteria for ZUMA-1 based on co-morbidities (Nastoupil, JCO 2020). Here we report results from this cohort at a median follow up of 32.4 months, as well as late outcomes of interest including cytopenias, infections and secondary malignancies. Methods and Results: The US Lymphoma CAR-T Consortium comprised of 17 US academic centers who contributed data independent of the manufacturer. Two hundred and ninety-eight patients underwent leukapheresis with intent to manufacture standard of care axi-cel as of September 30, 2018. In infused patients (n=275), OS and PFS were calculated from date of infusion. After median follow-up of 32.4 months (95% CI 31.1 - 34.3), median OS was not reached (95% CI 25.6 - not evaluable) (Figure 1A) with 1-, 2- and 3-year OS of 68.5% (95% CI 62.6-73.7), 56.4% (95% CI 50.1-62.2) and 52.2% (95% CI 45.7-58.2%), respectively. Median PFS was 9 months (95% CI 5.9-19.6) (Figure 1B); 1-, 2- and 3-year PFS was 47.4% (95% CI 41.4-53.2), 41.6% (95% CI 35.6-47.5) and 37.3% (95% CI 31.3-43.2), respectively. Twenty-seven PFS events occurred at or after 1 year post infusion;19 events were progressive lymphoma, with the latest relapse observed 28 months after axi-cel infusion. Eight patients died while in remission from their lymphoma: 4 from secondary malignancy, 3 from infection, and 1 from unknown causes. Results of multivariable modeling were similar to our prior analysis: factors associated with both a shorter PFS and shorter OS included male sex, elevated pre-lymphodepletion LDH, and poor ECOG status. Complete blood count and B- and T-cell recovery data were collected at 1 and 2-years post-infusion, excluding patients who had relapsed or been treated for secondary malignancy at time of collection (Table 1). Rates of neutropenia (absolute neutrophil count ≤1000) at 1- and 2- years were 9.2% (10/109) and 11.2% (9/80) and rates of CD4 count ≤200/ul were 62% (23/37) and 27% (7/26). Recovery of B cells was seen in 54% (15/28) and 57% (13/23) at 1-and 2-years post infusion. Infections were reported in 31.2% (34/109) patients between 6- and 12-months post infusion, and 17% (18/109) were severe, requiring either hospitalization and/or IV antibiotics. Twenty-one patients (24%, 21/89) had an infection between 1- and 2- years, 11% of which were severe. Twenty percent (10/49) of patients between 2- and 3-years had an infection and 4 (8%) were severe. Neutropenia, low CD4 counts, and IgG levels were not associated with infection, though patients with infection between 6-12 months were more likely to have received IVIG (p<0.001). No patient in this cohort died of COVID-19. Twenty-two of 275 (8%) patients were diagnosed with subsequent malignancy after axi-cel treatment: 14/275 (5%) patients were diagnosed with myeloid malignancies (MDS (n=12), AML (n=1), CMML (n=1)); other malignancies included squamous cell carcinoma of skin (n=3); sarcoma (n=1); endometrial (n=1); lung (n=1); mesothelioma (n=1) and AITL (n=1). Patients with myeloid malignancy had a median age of 62 at axi-cel apheresis (IQR 56-67), 64% were male and median lines of prior therapy was 4 (IQR 3-6), including 36% with a prior autologous stem cell transplant. Eleven patients were in remission from lymphoma at myeloid malignancy diagnosis, while 3 were diagnosed after progression and interval therapy. Conclusion: This multi-center retrospective study showed similar long-term results to the ZUMA-1 trial, despite including patients who did not meet ZUMA-1 eligibility criteria based on comorbidities. Sixteen percent of PFS events were seen after 1 year, largely due to disease progression. Late infection was common but was not explained by persistent neutropenia or low CD4 counts. Subsequent malignancy, including MDS, occurred in 8% of patients and require further study to better identify patients at risk. J.Y.S and M.D.J contributed equally; S.D and M.L contributed equally. Figure 1 Figure 1. Disclosures Jain: BMS, Kite/Gilead, Novartis, Precision Biosciences, Takeda: Consultancy. Nastoupil: Pfizer: Honoraria, Research Funding; MorphoSys: Honoraria; Takeda: Honoraria, Other: DSMC, Research Funding; ADC Therapeutics: Honoraria; IGM Biosciences: Research Funding; Genentech: Honoraria, Research Funding; Epizyme: Honoraria, Research Funding; Caribou Biosciences: Research Funding; Gilead/Kite: Honoraria, Research Funding; TG Therapeutics: Honoraria, Research Funding; Denovo Pharma: Other: DSMC; Bayer: Honoraria; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; Bristol Myers Squibb/Celgene: Honoraria, Research Funding. Ghobadi: Atara: Consultancy; Amgen: Consultancy, Research Funding; Wugen: Consultancy; Celgene: Consultancy; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding. Lin: Gamida Cell: Consultancy; Juno: Consultancy; Merck: Research Funding; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding; Sorrento: Consultancy; Legend: Consultancy; Takeda: Research Funding; Vineti: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding. Reagan: Seagen: Research Funding; Kite, a Gilead Company: Consultancy; Genentech: Research Funding; Curis: Consultancy. Oluwole: Curio Science: Consultancy; Janssen: Consultancy; Pfizer: Consultancy; Kite, a Gilead Company: Consultancy, Research Funding. McGuirk: EcoR1 Capital: Consultancy; Gamida Cell: Research Funding; Bellicum Pharmaceuticals: Research Funding; Novartis: Research Funding; Kite/ Gilead: Consultancy, Honoraria, Other: travel accommodations, expense, Kite a Gilead company, Research Funding, Speakers Bureau; Novartis: Research Funding; Juno Therapeutics: Consultancy, Honoraria, Research Funding; Astelllas Pharma: Research Funding; Pluristem Therapeutics: Research Funding; Fresenius Biotech: Research Funding; Allovir: Consultancy, Honoraria, Research Funding; Magenta Therapeutics: Consultancy, Honoraria, Research Funding. Deol: Kite, a Gilead Company: Consultancy. Sehgal: Juno/Celgene: Research Funding; Kite/Gilead: Research Funding. Goy: AstraZeneca: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; LLC(Targeted Oncology): Consultancy; Xcenda: Consultancy, Honoraria; Xcenda: Consultancy; Acerta: Consultancy, Research Funding; AbbVie/Pharmacyclics: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: 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, Research Funding; Vincerx: Honoraria, Membership on an entity's Board of Directors or advisory committees; Elsevier's Practice Update Oncology, Intellisphere, LLC(Targeted Oncology): Consultancy; Hoffman la Roche: Consultancy; Gilead: Membership on an entity's Board of Directors or advisory committees; AbbVie/Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Janssen: Research Funding; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Phamacyclics: Research Funding; Bristol Meyers Squibb: Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Michael J Hennessey Associates INC: Consultancy; Genentech/Hoffman la Roche: Research Funding; MorphoSys: Honoraria, Other; Karyopharm: Research Funding; Vincerx pharma: Membership on an entity's Board of Directors or advisory committees; Physicians' Education Resource: Consultancy, Other: Meeting/travel support; Incyte: Honoraria; Medscape: Consultancy; Novartis: Consultancy, Honoraria; Genomic Testing Cooperative: Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Other: Leadership role; Infinity/Verastem: Research Funding; Rosewell Park: Consultancy; Bristol Meyers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Kite, a Gilead Company: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; OncLive Peer Exchange: Honoraria; Elsevier PracticeUpdate: Oncology: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding; Constellation: Research Funding; COTA (Cancer Outcome Tracking Analysis): Current holder of stock options in a privately-held company, Membership on an entity's Board of Directors or advisory committees, Other: Leadership role; Hackensack Meridian Health, Regional Cancer Care Associates/OMI: Current Employment. Hill: Pfizer: Consultancy, Honoraria; Beigene: Consultancy, Honoraria, Research Funding; Gentenech: Consultancy, Honoraria, Research Funding; Kite, a Gilead Company: Consultancy, Honoraria, Other: Travel Support, Research Funding; Karyopharm: Consultancy, Honoraria, Research Funding; AstraZenica: Consultancy, Honoraria; Epizyme: Consultancy, Honoraria; Incyte/Morphysis: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria, Research Funding; Celgene (BMS): Consultancy, Honoraria, Research Funding; AbbVie: Consultancy, Honoraria, Research Funding. Andreadis: CRISPR Therapeutics: Research Funding; GenMAB: Research Funding; Novartis: Research Funding; Roche: Current equity holder in publicly-traded company, Ended employment in the past 24 months; Epizyme: Honoraria; Incyte: Honoraria; TG Therapeutics: Honoraria; Kite: Honoraria; Karyopharm: Honoraria; Atara: Consultancy, Honoraria; BMS: Research Funding; Merck: Research Funding. Muñoz: Seagen: Consultancy, Honoraria, Speakers Bureau; Pharmacyclics: Consultancy, Speakers Bureau; Bayer: Consultancy, Speakers Bureau; Kite, a Gilead Company: Consultancy, Speakers Bureau; Pfizer: Consultancy; Janssen: Consultancy, Speakers Bureau; Juno/Celgene: Consultancy; Bristol Myers Squibb: Consultancy; Alexion: Consultancy; BeiGene: Consultancy, Speakers Bureau; Fosunkite: Consultancy; Innovent: Consultancy; Debiopharma: Consultancy; Karyopharm: Consultancy; Genmab: Consultancy; ADC Therapeutics: Consultancy; Epizyme: Consultancy; Servier: Consultancy; Acrotech: Speakers Bureau; Verastem: Speakers Bureau; AstraZeneca: Speakers Bureau; Celgene/Bristol Myers Squibb: Speakers Bureau; Genentech: Speakers Bureau; Aurobindo: Speakers Bureau; Physicians' Education Resource: Honoraria; Kyowa Kirin: Consultancy, Honoraria, Speakers Bureau; OncView: Honoraria; Targeted Oncology: Honoraria. Westin: AstraZeneca: Consultancy, Research Funding; 47 Inc: Research Funding; Bristol Myers Squibb: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Morphosys: Research Funding; ADC Therapeutics: Consultancy, Research Funding; Umoja: Consultancy; Iksuda Therapeutics: Consultancy; MorphoSys: Consultancy, Research Funding; Curis: Research Funding; Genentech: Consultancy, Research Funding. Chavez: Bristol Myers Squibb: Speakers Bureau; Karyopharm Therapeutics: Consultancy; ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Kite/Gilead: Consultancy; Abbvie: Consultancy; MorphoSys: Speakers Bureau; BeiGene: Speakers Bureau; Novartis: Consultancy; Adaptive: Research Funding; Epizyme: Speakers Bureau; AstraZeneca: Research Funding. Bennani: Kyowa Kirin: Other: Advisory Board; Daichii Sankyo Inc: Other: Advisory Board; Purdue Pharma: Other: Advisory Board; Verastem: Other: Advisory Board; Vividion: Consultancy, Other: Advisory Board. Vose: Kite, a Gilead Company: Honoraria, Research Funding. Miklos: Pharmacyclics: Patents & Royalties; Adaptive Biotechnologies, Novartis, Juno/Celgene-BMS, Kite, a Gilead Company, Pharmacyclics-AbbVie, Janssen, Pharmacyclics, AlloGene, Precision Bioscience, Miltenyi Biotech, Adicet, Takeda: Membership on an entity's Board of Directors or advisory committees; Kite, a Gilead Company, Amgen, Atara, Wugen, Celgene, Novartis, Juno-Celgene-Bristol Myers Squibb, Allogene, Precision Bioscience, Adicet, Pharmacyclics, Janssen, Takeda, Adaptive Biotechnologies and Miltenyi Biotechnologies: Consultancy; Pharmacyclics, Amgen, Kite, a Gilead Company, Novartis, Roche, Genentech, Becton Dickinson, Isoplexis, Miltenyi, Juno-Celgene-Bristol Myers Squibb, Allogene, Precision Biosciences, Adicet, Adaptive Biotechnologies: Research Funding. Neelapu: Takeda Pharmaceuticals and related to cell therapy: Patents & Royalties; Kite, a Gilead Company, Merck, Bristol Myers Squibb, Novartis, Celgene, Pfizer, Allogene Therapeutics, Cell Medica/Kuur, Incyte, Precision Biosciences, Legend Biotech, Adicet Bio, Calibr, Unum Therapeutics and Bluebird Bio: Honoraria; Kite, a Gilead Company, Bristol Myers Squibb, Merck, Poseida, Cellectis, Celgene, Karus Therapeutics, Unum Therapeutics (Cogent Biosciences), Allogene, Precision BioSciences, Acerta and Adicet Bio: Research Funding; Kite, a Gilead Company, Merck, Bristol Myers Squibb, Novartis, Celgene, Pfizer, Allogene, Kuur, Incyte, Precision BioSciences, Legend, Adicet Bio, Calibr, and Unum Therapeutics: Other: personal fees. Locke: GammaDelta Therapeutics: Consultancy, Other: Scientific Advisory Role; BMS/Celgene: Consultancy, Other: Scientific Advisory Role; Bluebird Bio: Consultancy, Other: Scientific Advisory Role; Calibr: Consultancy, Other: Scientific Advisory Role; Amgen: Consultancy, Other: Scientific Advisory Role; Allogene Therapeutics: Consultancy, Other: Scientific Advisory Role, Research Funding; Cellular Biomedicine Group: Consultancy, Other: Scientific Advisory Role; Wugen: Consultancy, Other; Takeda: Consultancy, Other; Novartis: Consultancy, Other, Research Funding; Umoja: Consultancy, Other; Cowen: Consultancy; EcoR1: Consultancy; Emerging Therapy Solutions: Consultancy; Gerson Lehrman Group: Consultancy; Moffitt Cancer Center: Patents & Royalties: field of cellular immunotherapy; Legend Biotech: Consultancy, Other; Janssen: Consultancy, Other: Scientific Advisory Role; Kite, a Gilead Company: Consultancy, Other: Scientific Advisory Role, Research Funding; Iovance Biotherapeutics: Consultancy, Other: Scientific Advisory Role. Dahiya: Kite, a Gilead Company: Consultancy; Atara Biotherapeutics: Consultancy; Miltenyi Biotech: Research Funding; Jazz Pharmaceuticals: Research Funding; BMS: Consultancy. Lunning: Spectrum: Consultancy; AstraZeneca: Consultancy; Acrotech: Consultancy; Legend: Consultancy; Novartis: Consultancy; Kyowa Kirin: Consultancy; Karyopharm: Consultancy; Morphosys: Consultancy; TG Therapeutics: Consultancy; Janssen: Consultancy; AbbVie: Consultancy; Verastem: Consultancy; Myeloid Therapeutics: Consultancy; Celgene, a Bristol Myers Squibb Co.: Consultancy; Daiichi-Sankyo: Consultancy; Beigene: Consultancy; ADC Therapeutics: Consultancy; Kite, a Gilead Company: Consultancy.

AbstractIntroductionData on cigarette smoking prevalence among Alaska Native and American Indian (ANAI) people are limited to cross-sectional studies or specific subpopulations. Using data from the Alaska Education and Research toward Health (EARTH) Study 10-year follow-up, this study assessed patterns of smoking from baseline and factors associated with current use.Aims and MethodsEARTH Study urban south central ANAI participants (N = 376; 73% women) provided questionnaire data on smoking at baseline and 10-year follow-up. Multivariable-adjusted logistic regression assessed whether gender, cultural factors (Tribal identity, language spoken in the home), depressive symptoms (PHQ-9), baseline smoking status, and baseline cigarettes per day (CPD) were associated with current smoking at follow-up.ResultsCurrent smoking was 27% and 23% at baseline and follow-up, respectively. Of baseline smokers, 60% reported smoking at follow-up (77% men, 52% women). From multivariable-adjusted analyses, the odds of current smoking at follow-up were lower among women than men, those who never or formerly smoked versus currently smoked at baseline, and smoking <10 CPD compared with ≥10 CPD at baseline. PHQ-9 score or cultural variables were not associated with smoking at follow-up. Smoking fewer baseline CPD was associated with former smoking status (ie, quitting) at follow-up among women, but not men.ConclusionsOur project is among the first to longitudinally explore smoking within an ANAI cohort. While we observed persistent smoking during a 10-year period, there were important differences by gender and CPD in quitting. These differences may be important to enhance the reach and efficacy of cessation interventions for ANAI people.ImplicationsThis study contributes novel longitudinal information on cigarette smoking prevalence during a 10-year period among Alaska Native and American Indian (ANAI) people. Prior data on smoking prevalence among ANAI people are limited to cross-sectional studies or specific subpopulations. Our project is among the first to longitudinally explore smoking prevalence within an ANAI cohort. We observed persistent smoking during a 10-year period. The study also contributes information on differences by gender and cigarettes smoked per day in quitting. These findings have implications for enhancing the reach and efficacy of cessation interventions for ANAI people.

SummaryErdheim–Chester disease (ECD) is a rare histiocytic neoplasm with frequent multiorgan involvement. An accurate diagnosis of ECD requires the correlation of clinical features, histopathologic and radiologic findings. We describe a case series of patients with a referral diagnosis of ECD, whereby the diagnosis was changed to non‐histiocytic diseases after comprehensive review at a tertiary care center. This accurate revision of the referral diagnosis of ECD enabled initiation of proper disease‐directed therapy in a timely manner for these patients and avoided unnecessary exposure to systemic cytotoxic chemotherapy or targeted agents. Our study highlights the value of a multidisciplinary team of histiocytosis experts in confirming the diagnosis of ECD and also brings attention to other conditions to consider that can mimic ECD, including osteopoikilosis, tenosynovial giant cell tumour, IgG4‐related disease, fibrous dysplasia and chronic recurrent multifocal osteomyelitis.

Background: Individuals with brachial plexus injuries (BPIs) can be prescribed assistive devices, including myoelectric elbow orthoses (MEOs), for rehabilitation or functional use after failed treatment for elbow flexion restoration. Although recent case studies indicate potential for clinical improvements after using an MEO after BPI, the patients' perspectives on such use are still unknown. Objective: To explore patient perspectives on the use of an MEO after surgical treatment for a traumatic BPI. Study design: Qualitative using both a focus group and semistructured interviews. Methods: Patients with BPI that used an MEO were recruited. Five patients participated in an in-person focus group, whereas three patients participated in individual phone interviews. Themes that emerged from the focus group were compared against those that emerged from the personal interviews. Results: Feedback was grouped into three themes: device usage, hardware performance, and device design. Within each theme, positive elements, areas for improvement, and additional considerations emerged. Patients indicated a positive attitude toward using an MEO as a rehabilitation tool. They desired a streamlined, stronger device to support them and assist during activities of daily living. Conclusions: For patients with BPI, a well-designed MEO that meets their needs could assist with rehabilitation and increase independence in daily activities. Continued patient engagement in the evaluation and development of both medical devices and treatment plans offers the best opportunity for improved outcomes that are important to the patient.

AbstractObjectiveDrug‐resistant epilepsy (DRE) occurs at higher rates in children <3 years old. Epilepsy surgery is effective, but rarely utilized in young children despite developmental benefits of early seizure freedom. The present study aims to identify unique patient characteristics and evaluation strategies in children <3 years old who undergo epilepsy surgery evaluation as a means to assess contributors and potential solutions to health care disparities in this group.MethodsThe Pediatric Epilepsy Research Consortium Epilepsy Surgery Database, a multicentered, cross‐sectional collaboration of 21 US pediatric epilepsy centers, collects prospective data on children <18 years of age referred for epilepsy surgery evaluation. We compared patient characteristics, diagnostic utilization, and surgical treatment between children <3 years old and those older undergoing initial presurgical evaluation. We evaluated patient characteristics leading to delayed referral (>1 year) after DRE diagnosis in the very young.ResultsThe cohort included 437 children, of whom 71 (16%) were <3 years of age at referral. Children evaluated before the age of 3 years more commonly had abnormal neurological examinations (p = .002) and daily seizures (p = .001). At least one ancillary test was used in 44% of evaluations. Fifty‐nine percent were seizure‐free following surgery (n = 34), with 35% undergoing limited focal resections. Children with delayed referrals more often had focal aware (p < .001) seizures and recommendation for palliative surgeries (p < .001).SignificanceThere are relatively few studies of epilepsy surgery in the very young. Surgery is effective, but may be disproportionally offered to those with severe presentations. Relatively low utilization of ancillary testing may contribute to reduced surgical therapy for those without evident lesions on magnetic resonance imaging. Despite this, a sizeable portion of patients have favorable outcome after focal epilepsy surgery resections.