Citations

Introduction: Cytokine release syndrome (CRS) is an expected and potentially life-threatening toxicity associated with CAR T cell therapy. Idecabtagene vicleucel (ide-cel, bb2121), a BCMA-directed CAR T cell therapy, demonstrated promising efficacy in triple-class exposed and highly refractory patients with multiple myeloma in the pivotal phase 2 KarMMa study, with an overall response rate (ORR), complete response (CR) rate, median duration of response, and median progression-free survival of 73%, 33%, 10.7 months, and 8.8 months, respectively, across the target dose levels of 150−450 × 106 CAR+ T cells, and 82%, 39%, 11.3 months, and 12.1 months at the highest target dose of 450 × 106 CAR+ T cells (Munshi et al. J Clin Oncol. 2020;38[suppl, abstr]:8503). Identifying the patterns of CRS evolution, associations with baseline patient and disease characteristics, and the impact of interventions are key to understanding this adverse event in the context of ide-cel. In addition, a better understanding of lower-grade CRS, including maximum grade 1 events, is important as these are easier to manage and represent a lower burden on the healthcare system. We report results of an examination of CRS events in the KarMMa study. Methods: Patients in the KarMMa trial (NCT03361748) were required to have ≥3 prior regimens (including an immunomodulatory agent, a proteasome inhibitor, and an anti-CD38 antibody) and were refractory to their last regimen per International Myeloma Working Group criteria. Patients received ide-cel target doses of 150, 300, or 450 × 106 CAR+ T cells 2 days after lymphodepletion with cyclophosphamide 300 mg/m2 plus fludarabine 30 mg/m2 daily for 3 days. The primary endpoint was ORR. The key secondary endpoint was CR rate; other secondary endpoints included safety. CRS was graded according to criteria in Lee et al. (Blood. 2014;124:188). Patient characteristics and CRS management were examined by CRS grade to identify variables associated with higher-grade CRS. Management of CRS included tocilizumab 8 mg/kg with the addition of corticosteroids and other agents as needed. Results: Of 128 patients treated with ide-cel, 107 (84%) experienced CRS; 61 patients (48%) had maximum grade 1 and 46 (36%) had maximum grade ≥2 CRS (grade 2, n=39; grade 3, n=5; grade 4, n=1; and grade 5, n=1). Baseline characteristics were generally balanced among patients with maximum grade 1 and grade ≥2 (Table). Thirty patients (65%) with maximum grade ≥2 CRS progressed from initial grade 1 events, whereas 16 (35%) had initial grade ≥2. Median time to onset of CRS was the same (1 day) regardless of initial or maximum grade (Table). Median duration was 5.0 days in patients with maximum grade 1, 5.5 days in patients with maximum grade 2, and 11.0 days in patients with maximum grade ≥3 CRS. Median duration was shorter in patients with maximum grade 1 CRS than in those with initial grade 1 events that progressed to grade ≥2 (5.0 days vs 7.0 days). Most patients (83%) with maximum grade ≥2 CRS received at least 1 dose of tocilizumab and approximately one-third (35%) received corticosteroids, compared with 48% and 5%, respectively, of patients with maximum grade 1 CRS. A higher percentage of patients with initial grade ≥2 vs initial grade 1 CRS received multiple doses of tocilizumab (50% vs 37%) or at least 1 dose of corticosteroids (50% vs 27%). Conclusions: Almost half of the patients treated with ide-cel experienced maximum grade 1 CRS. Baseline disease and patient characteristics were similar among patients experiencing grade 1 and higher-grade CRS events. CRS was effectively managed with tocilizumab and corticosteroids, and more frequent use of these interventions in patients with grade ≥2 CRS was not associated with prolonged CRS events. The time to onset of CRS was predictable and equivalent in patients with maximum grade 1 and higher-grade CRS events. Duration of CRS was similar in patients with maximum grade 1 and 2 but was longer in patients with maximum grade ≥3 CRS. These data demonstrate the feasible management of CRS and thus confirm the tolerability of ide-cel in patients with relapsed and refractory multiple myeloma. Table 1 Disclosures Kansagra: Karyopharm: Honoraria; Pharmacyclics: Honoraria; Alnylam: Honoraria; BMS: Honoraria; GSK: Honoraria; Janssen: Honoraria; Takeda: Honoraria; Sanofi: Honoraria. Lin:Novartis: Consultancy; Sorrento: Consultancy, Membership on an entity's Board of Directors or advisory committees; Gamida Cells: Consultancy; Janssen: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Vineti: Consultancy; Takeda: Research Funding; Celgene: Consultancy, Research Funding; Bluebird Bio: Consultancy, Research Funding; Juno: Consultancy; Legend BioTech: Consultancy; Merck: Research Funding. Berdeja:BMS: Consultancy, Research Funding; Cellularity: Research Funding; Lilly: Research Funding; Amgen: Consultancy, Research Funding; Abbvie: Research Funding; Poseida: Research Funding; Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Bioclinica: Consultancy; Bluebird: Research Funding; Prothena: Consultancy; Legend: Consultancy; Kesios: Research Funding; Kite Pharma: Consultancy; Karyopharm: Consultancy; Constellation: Research Funding; Novartis: Research Funding; Teva: Research Funding; Servier: Consultancy; Takeda: Consultancy, Research Funding; CRISPR Therapeutics: Consultancy, Research Funding; Glenmark: Research Funding; EMD Sorono: Research Funding; Vivolux: Research Funding; Genentech, Inc.: Research Funding; CURIS: Research Funding; Acetylon: Research Funding. Shah:GSK, Amgen, Indapta Therapeutics, Sanofi, BMS, CareDx, Kite, Karyopharm: Consultancy; BMS, Janssen, Bluebird Bio, Sutro Biopharma, Teneobio, Poseida, Nektar: Research Funding. Oriol:Celgene: Consultancy, Speakers Bureau; Amgen: Consultancy, Speakers Bureau; Janssen: Consultancy. Yakoub-Agha:Celgene: Honoraria; Jazz Pharmaceuticals: Honoraria; Novartis: Honoraria; Gilead/Kite: Honoraria, Other: travel support; Janssen: Honoraria. Einsele:Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Speakers Bureau; Sanofi: Consultancy, Honoraria, Research Funding, Speakers Bureau; Celgene: Consultancy, Honoraria, Research Funding, Speakers Bureau; GlaxoSmithKline: Honoraria, Research Funding, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding, Speakers Bureau. Rambaldi:BMS/Celgene: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); University of Milan: Current Employment; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Support of parent study and funding of editorial support. Received travel support., Research Funding; Omeros: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company). Advisory board and speaker fees from Pfizer.; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company). Research grant from Amgen Inc.; Sanofi: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Astellas: Honoraria, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support from Gilead.. Truppel-Hartmann:bluebird bio, Inc: Current Employment, Other: TRAVEL, ACCOMMODATIONS, EXPENSES (paid by any for-profit health care company); F. Hoffmann La Roche: Current equity holder in publicly-traded company, Ended employment in the past 24 months. Rowe:Bristol-Myers Squibb: Current Employment. Wang:Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Agarwal:Bristol-Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Campbell:BMS: Current Employment, Current equity holder in publicly-traded company. Lonial:Takeda: Consultancy, Other: Personal fees, Research Funding; Amgen: Consultancy, Honoraria, Other: Personal fees; Novartis: Consultancy, Honoraria, Other: Personal fees; Millennium: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Other: Personal fees, Research Funding; BMS: Consultancy, Honoraria, Other: Personal fees, Research Funding; Onyx: Honoraria; Genentech: Consultancy; Karyopharm: Consultancy; Sanofi: Consultancy; TG Therapeutics: Membership on an entity's Board of Directors or advisory committees; Merck: Consultancy, Honoraria, Other: Personal fees; JUNO Therapeutics: Consultancy; GSK: Consultancy, Honoraria, Other: Personal fees; Abbvie: Consultancy.

Introduction: Among the most challenging complications of hemophilia A is inhibitor formation. A T-cell dependent B-cell response to exogenous factor VIII (FVIII), inhibitors result in a high burden of disease, with poorly controlled bleeding, twice the hospitalizations, 10-fold the cost, and 3.5-fold the mortality of non-inhibitor patients. Thus, a major goal of hemophilia management is to prevent and eradicate inhibitors. With the availability of novel therapies, including eloctate, a recombinant Fc-fusion protein (rFVIII-Fc) which induces regulatory T cells to promote FVIII tolerance, and emicizumab, a bispecific monoclonal FVIII mimetic, we designed the INHIBIT Clinical Trials Platform (X01HL143024), Fig.1. The platform is composed of two linked randomized phase III trials, the Inhibitor Prevention Trial (NCT04303559), comparing rFVIII-Fc vs emicizumab prophylaxis to prevent inhibitors, and the Inhibitor Eradication Trial (NCT04303572), comparing rFVIII-Fc immune tolerance induction (ITI) plus emicizumab vs rFVIII-Fc ITI alone to eradicate inhibitors. The platform uses adaptive design to incorporate historical data (Bayesian priors) on inhibitor formation to increase power and promote efficient use of rare data. Yet, there is equipoise regarding the optimal approach to inhibitor prevention and eradication, and, as clinical practice is changing, we aimed to test the feasibility of the INHIBIT trial design. Methods: To establish design feasibility, we conducted interviews with 30 hemophilia treatment center (HTC) physicians participating in the INHIBIT trials, to determine prophylaxis and tolerance regimens they prescribe and perceived barriers to the INHIBIT trials design. A 4-question survey was subsequently emailed to these physicians to ascertain the initial prophylaxis regimens they prescribe in previously untreated patients (PUPs) with severe hemophilia A, and the initial immune tolerance induction (ITI) they prescribe in high-responding inhibitor patients with severe hemophilia A; if new inhibitors had been observed during emicizumab prophylaxis, and willingness to participate in post-trial surveillance. Results: In interviews, HTC physicians indicated the issues that influenced choice of prophylaxis/ ITI regimen were patient preference, family history of inhibitors, infusion frequency, IV access, port requirement, and family fatigue. In the absence of clinical trials data in PUPs, there was general agreement that emicizumab prophylaxis, with it simpler subcutaneous (SQ) administration, might delay or potentially prevent inhibitors. Survey findings in Table 1 indicated 75% of physicians prescribe extended half-life (EHL) FVIII in a once-weekly prophylaxis regimen, as planned in the Prevention Trial, despite the persistent 27% inhibitor rate (ALong PUPs Trial, Königs et al, ISTH 2020) and potential risks with port use. There was support for the 1:3 preferential randomization to emicizumab in the Prevention Trial due to the simpler SQ route, despite concern it might delay rather than prevent inhibitor formation, although no inhibitors were reported by physician survey with emicizumab use alone. There was also concern that breakthrough bleeds requiring FVIII during emicizumab prophylaxis, might lead to immune activation and inhibitor formation. There was strong agreement, however, in 29 (97%) of physicians to participate in post-trial surveillance for long-term inhibitor outcomes. FVIII ITI was considered essential to eradicate inhibitors, despite the intensity of the infusion regimen. Notably, 60% prescribe emicizumab with FVIII ITI, as planned in the Eradicate Trial, although the every-other-day infusion was considered a potential barrier to participation. Omitting FVIII ITI was not favored due to the risk of inhibitor anamnesis if FVIII treatment was subsequently required for surgery or acute hemorrhages. Despite these concerns, there was agreement to participate in the trials. Discussion: Physician interviews and surveys confirm there is heterogeneity in current hemophilia clinical practice, specifically in initial prophylaxis regimens and in initial immune tolerance regimens, including agent choice and duration. However, there is physician consensus with the INHIBIT trial aims and with the proposed INHIBIT trial regimens to prevent and eradicate inhibitors. Disclosures Ragni: Bioverativ: Membership on an entity's Board of Directors or advisory committees, Research Funding; Alnylam/Sanofi: Membership on an entity's Board of Directors or advisory committees, Research Funding; BioMarin: Membership on an entity's Board of Directors or advisory committees, Research Funding; ATHN: Research Funding; Sangamo: Research Funding. Seaman:Bayer: Consultancy; Genentech: Consultancy; Spark Therapeutics: Consultancy; Takeda: Consultancy. Acharya:Novonordisk: Membership on an entity's Board of Directors or advisory committees; BPL: Membership on an entity's Board of Directors or advisory committees; Bayer Pharma Inc.: Research Funding. Wheeler:Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; Biomarin: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; UniQure: Membership on an entity's Board of Directors or advisory committees. Tarango:Takeda/Shire: Honoraria, Other; Bayer: Consultancy, Other; Sanofi: Honoraria, Other. Dunn:ATHN: Research Funding; Spire: Honoraria; Medscape: Honoraria; World Federation of Hemophilia USA: Membership on an entity's Board of Directors or advisory committees; Takeda: Research Funding; BioMarin: Research Funding; uniQure: Consultancy; Genentech, Inc.: Consultancy; Nationwide Children's Hospital: Current Employment. Kulkarni:Sanofi/ Bioverativ, Bayer, Biomarin, Shire/Takeda, Novo Nordisk, Freeline: Other: clinical trial research grants ; Bioverativ/Sanofi, BPL, Genentech, Kedrion, Novo Nordisk, Octapharma, Pfizer, Takeda, Catalyst Bioscience Bayer: Membership on an entity's Board of Directors or advisory committees. Ahuja:Genentech: Consultancy, Honoraria; Sanofi Genzyme: Consultancy, Honoraria; XaTek, Inc.: Consultancy, Patents & Royalties, Research Funding. Chitlur:Takeda: Honoraria; Biovertiv: Honoraria; Agios Pharmaceuticals: Research Funding; Pfizer: Honoraria; Novo Nordisk: Consultancy, Honoraria. Pipe:Apcintex, Bayer, BioMarin, Catalyst Biosciences, CSL Behring, HEMA Biologics, Freeline, Novo Nordisk, Pfizer, F. Hoffmann-La Roche Ltd/Genentech, Inc., Sangamo Therapeutics, Sanofi, Takeda, Spark Therapeutics, uniQure: Consultancy; Siemens: Research Funding; Medical and Scientific Advisory Council to the National Hemophilia Foundation; Medical Advisory Board to World Federation of Hemophilia: Membership on an entity's Board of Directors or advisory committees. Malec:Sanofi Genzyme: Consultancy, Research Funding, Speakers Bureau; CSL: Consultancy; Takeda: Consultancy; Bayer: Consultancy; SOBI: Consultancy. Leissinger:Bayer: Consultancy; Kedrion: Consultancy; CSL Behring: Membership on an entity's Board of Directors or advisory committees; Genentech: Consultancy; HEMA Biologics: Consultancy; Takeda: Consultancy; Uniqure: Consultancy; Spark: Consultancy. Carpenter:Hemostasis & Thrombosis Research Society: Membership on an entity's Board of Directors or advisory committees; American Academy of Pediatrics: Other: PREP Heme/Onc editorial board; Kedrion: Honoraria; Novo Nordisk: Honoraria; Genentech, Inc.: Honoraria; American Thrombosis and Hemostasis Network: Membership on an entity's Board of Directors or advisory committees; CSL Behring: Research Funding; Shire: Research Funding. Knoll:NovoNordisk: Membership on an entity's Board of Directors or advisory committees. Wang:Bioverativ Inc: Honoraria; Bayer: Honoraria; CSL Behring: Honoraria; Biomarin: Honoraria; Genentech: Honoraria; Takeda: Honoraria. Young:Genentech/Roche, Grifols, and Takeda: Research Funding; Bayer, CSL Behring, Freeline, UniQure: Consultancy; BioMarin, Freeline, Genentech/Roche, Grifols, Kedrion, Novo Nordisk, Sanofi Genzyme, Spark, Takeda, and UniQure: Honoraria. Thornburg:Genentech: Speakers Bureau; Spark Therapeutics: Consultancy; Bluebird Bio: Consultancy; Ironwood Pharmaceuticals: Consultancy, Other: Data Safety Monitoring Board; American Thrombosis and Hemostasis Network: Research Funding; Sanofi Genzyme: Consultancy, Other: Data Safety Monitoring Board, Research Funding; NovoNordisk: Research Funding; Biomarin: Consultancy, Speakers Bureau; Bayer Pharmaceuticals: Research Funding; National Hemophilia Foundation: Membership on an entity's Board of Directors or advisory committees, Research Funding. Lucas:CRISPR Therapeutics: Membership on an entity's Board of Directors or advisory committees. Hwang:Shire: Honoraria; Takeda: Honoraria.

Background: Plasmablastic lymphoma (PBL) is a rare subtype of Non-Hodgkin Lymphoma with a well-known association with HIV infection. The outcomes of PBL patients are typically described with high relapse rates and poor prognosis. (Loghavi S, J Hematol Oncol. 2015; Morscio J, Am J of Pathol. 2014; Castillo JJ, Clin Lymphoma Myeloma Leuk. 2011; Castillo JJ, Am J Hematol. 2008) There has been a paucity of data suggesting that limited stage disease (Ann Arbor stage I-II) may have a more favorable prognosis. However, due to the rarity of this disease there have been no large-scale reviews to confirm this. Thus, many patients with limited stage disease are subject to the aggressive therapy recommendations based on the poor outcomes of PBL patients as a whole. (Loghavi S, J Hematol Oncol. 2015; NCCN Guidelines, version 2.2020; Al-Malki MM, BBMT. 2014) We attempted to determine the treatment patterns and outcomes of patients with limited stage PBL. Methods: We conducted a multi-center (13 US academic centers) retrospective study of patients with limited stage (Ann Arbor stage I-II) Plasmablastic lymphoma. Determination of limited stage and diagnosis of PBL was determined by the investigators at each individual center. Patients diagnosed between 1/1/1990 and 6/1/2018 were included. Baseline demographic, clinical, laboratory, pathology, and outcomes data were extracted by retrospective chart review. Kaplan Meier was utilized for time to event analysis. Results: Baseline characteristics are included in table 1. A total of 80 patients were identified with limited stage disease. With a median follow up of 34 months the 3-yr Progression free survival (PFS) and overall survival (OS) was 71.9% and 78.7% respectively (Figure 1A and 1B). Patients that received frontline chemotherapy with (n=29) and without RT (n=36) had a 3-yr PFS and OS of 84.6% and 96.2% as compared to 64.5% and 70.8%, respectively (Figure 2A and 2B; Figure 3A and 3B). The Hazard ratio (HR) for PFS and OS for chemo (reference) vs chemo-RT was 0.47 (95% CI 0.18-1.3; P=0.131) and 0.18 (95% CI 0.04-0.84; p=0.029) respectively. The HR for PFS and OS for CHOP (n=14, reference) vs EPOCH (n=33) based regimens was 0.37 (95% CI 0.11-1.2; p=0.106) and 0.36 (95% CI 0.079-1.6; p=0.182) respectively. Patients with stage I/IE disease (n=56) had a 3-yr PFS and OS of 73.1% and 81.2% respectively. Patients with stage II/IIE disease (n=24) had a 3-yr PFS and OS of 69.3% and 73.4% respectively. Patients that received aggressive treatment (n=17) with Hyper-CVAD based regimens and/or Auto-SCT as consolidation had a 3-yr PFS and OS of 63.6% and 72.7% respectively. Patients with concomitant HIV (n=16) had a 3-yr PFS and OS of 80.8% and 77.4% respectively. Seven patients received RT alone and 6 patients had surgical resection alone as frontline therapy; 1 patient received no therapy; 1 patient received HAART therapy only and remains in CR without any other treatment for PBL 29 months after diagnosis. There were 8 deaths (10%) related to PBL, 3 deaths (4%) related to treatment of PBL (2 during frontline chemo and 1 upon relapse with salvage chemo), and 9 deaths (11%) related to other causes. The 3-yr lymphoma free survival (LFS) of the entire cohort, pts receiving chemo alone, and pts receiving chemo-RT (without including treatment related mortality (TRM) as an event) was 89.1%, 85.2%, and 100% respectively. The 3-yr LFS survival of the entire cohort, pts receiving chemo alone, and pts receiving chemo-RT (including TRM as an event) was 85.1%, 80.0%, and 96.2% respectively. Discussion: Here we report the largest review to our knowledge of limited stage PBL. Outcomes appear to be excellent with 3-yr PFS and OS of 71.9% and 78.7% respectively and a 3-yr LFS of 89.1% (85.1% when attributing TRM as an event). There was no obvious benefit to receiving aggressive therapy with H-CVAD based regimens and/or Auto-SCT. Although this is a small, uncontrolled sample size the HR for OS was improved in patients receiving frontline chemo-RT vs chemo alone 0.18 (95% CI 0.04-0.84; p=0.029). However, this did not take into account TRM with or progression while receiving frontline chemotherapy. Patients who were HIV+ had similar PFS and OS outcomes compared to the entire cohort. This retrospective study clearly demonstrates the favorable outcomes in this patient population, especially in those able to receive definitive therapy for their disease. Disclosures Hess: ADC Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees; BMS, AstraZeneca: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Patel:Takeda: Consultancy, Research Funding; Precision Biosciences: Research Funding; Nektar: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Bristol Myers Squibb: Consultancy, Research Funding; Poseida: Research Funding; Cellectis: Research Funding; Oncopeptides: Consultancy; Janssen: Consultancy, Research Funding. Nowakowski:Nanostrings: Research Funding; Seattle Genetics: Consultancy; Curis: Consultancy; Ryvu: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other; Kymera: Consultancy; Denovo: Consultancy; Kite: Consultancy; Celgene/BMS: Consultancy, Research Funding; Roche: Consultancy, Research Funding; MorphoSys: Consultancy, Research Funding. Chavez:Bayer: Consultancy; AbbVie: Consultancy; BeiGene: Speakers Bureau; Morphosys: Consultancy, Speakers Bureau; Merck: Research Funding; AstraZeneca: Speakers Bureau; Celgene: Consultancy; Genentech: Speakers Bureau; Epizyme: Speakers Bureau; Gilead: Consultancy; Novartis: Consultancy; Kite, a Gilead Company: Consultancy, Speakers Bureau; Karyopharm: Consultancy; Verastem: Consultancy; Pfizer: Consultancy. Hill:Beigene: Consultancy, Honoraria, Research Funding; Abbvie: Consultancy, Honoraria, Research Funding; Genentech: Consultancy, Honoraria, Research Funding; Takeda: Research Funding; AstraZenica: Consultancy, Honoraria, Research Funding; Kite, a Gilead Company: Consultancy, Honoraria, Research Funding; Novartis: Consultancy, Honoraria; BMS: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Pharmacyclics: Consultancy, Honoraria, Research Funding; Karyopharm: Consultancy, Honoraria, Research Funding. Maddocks:Pharmacyclics: Consultancy, Honoraria; Morphosys: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Seattle Genetics: Consultancy, Honoraria; Karyopharm: Consultancy; ADC Therapeutics, AstraZeneca: Consultancy; BMS: Consultancy, Research Funding. Wagner-Johnston:ADC Therapeutics, Regeneron, CALIB-R, Verastem: Membership on an entity's Board of Directors or advisory committees. Kahl:AstraZeneca Pharmaceuticals LP: Consultancy, Membership on an entity's Board of Directors or advisory committees; AbbVie: Consultancy; Pharmacyclics LLC: Consultancy; Genentech: Consultancy; Acerta: Consultancy, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Consultancy; ADC Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BeiGene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche Laboratories Inc: Consultancy. Alderuccio:ADC Therapeutics: Membership on an entity's Board of Directors or advisory committees; Forma Therapeutics: Other: Family member; Agios Pharmaceuticals: Other: Family member; Oncinfo: Honoraria; Inovio Pharmaceuticals: Other: Family member; Foundation Medicine: Other: Family member; Puma Biotechnology: Other: Family member; OncLive: Honoraria. Lossos:Janssen Biotech: Honoraria; Verastem: Consultancy, Honoraria; Janssen Scientific: Consultancy, Other; Seattle Genetics: Consultancy, Other; Stanford University: Patents & Royalties; NCI: Research Funding. Portell:Bayer: Consultancy; BeiGene: Consultancy, Research Funding; Kite: Consultancy, Research Funding; Acerta/AstraZeneca: Research Funding; Amgen: Consultancy; Janssen: Consultancy; Pharmacyclics: Consultancy; AbbVie: Research Funding; TG Therapeutics: Research Funding; Infinity: Research Funding; Roche/Genentech: Consultancy, Research Funding; Xencor: Research Funding. Landsburg:Celgene: Membership on an entity's Board of Directors or advisory committees; Triphase: Research Funding; Takeda: Research Funding; Curis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Morphosys: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Speakers Bureau. Castillo:TG Therapeutics: Research Funding; Beigene: Consultancy, Research Funding; Kymera: Consultancy; Janssen: Consultancy, Research Funding; Abbvie: Research Funding; Pharmacyclics: Consultancy, Research Funding.

Introduction: Chimeric antigen receptor (CAR) T cell therapy directed against B-cell maturation antigen (BCMA) has shown promising results for the treatment of relapsed refractory multiple myeloma (RRMM). bb21217 is an anti-BCMA CAR T cell therapy that uses the same CAR molecule as idecabtagene vicleucel (bb2121), but adds the PI3K inhibitor bb007 during ex vivo culture to enrich the drug product (DP) for memory-like T cells, thereby reducing the proportion of highly differentiated or senescent T cells. To investigate whether DP properties correlate with clinical outcomes including duration of response (DOR), we conducted extensive molecular characterization of patient DPs. Methods: CRB-402 (NCT03274219) is an ongoing, multi-center phase 1 dose escalation trial of bb21217 in RRMM patients who received ≥3 prior regimens, including proteasome inhibitor and immunomodulatory agent, or are double-refractory to both classes. In the expansion cohort, patients additionally required prior exposure to an anti-CD38 antibody and were required to be refractory to last line. Planned enrollment is 74 patients, including 50 in the expansion cohort. Patients undergo lymphodepletion with fludarabine (30 mg/m2) and cyclophosphamide (300 mg/m2) daily for 3 days, then receive a single infusion of bb21217 at 150, 300 or 450 x 106 CAR+ T cells. The primary outcome measure is incidence of adverse events (AEs), including dose-limiting toxicities (DLTs). Additional outcome measures include overall response rate and DOR by IMWG Uniform Response Criteria. We profiled DP and apheresis starting material (PBMC) by RNAseq and cyTOF and correlated expression of memory/senescence markers from apheresis to DP with clinical outcomes, including DOR. Results: Asof March 1, 2020, 46 patients (median age 62 [33-74]) received bb21217, 24 in escalation (12 at 150, 6 at 300 and 6 at 450) and 22 in expansion (8 at 300 and 14 at 450); median follow up for all patients is 8.5 (<1-29) months. Patients had a median of 6 (3-17) prior lines of therapy with 26/46 (57%) triple refractory. Cytokine release syndrome (CRS) developed in 31/46 (67%) patients and included one death (14 G1, 15 G2, 1 G3 and 1 G5). Median time to first onset was 3 days (1-20); tocilizumab (18 pts) +/- corticosteroids (6 pts) was used to manage CRS. Ten (22%) patients developed neurotoxicity [5 G1, 2 G2, 2 G3, 1 G4] with median time to first onset of 7 (3-24) days. Response was assessed per investigator for 44 patients with ≥ 2 months of follow up or PD/death within 2 months. Twenty-four (55%) patients had confirmed response per IMWG criteria including 8 (18%) with ≥CR and 13 (30%) with VGPR. Median time to CR was 2.5 (1-24) months. The median DOR was 11.9 (95% CI: 8.1-17.0) months across target dose levels of 150-450 x106 CAR+ T cells. The 450 target dose was selected as the RP2D and dose expansion is ongoing. bb21217 DPs from 44 patients were characterized. Paired analysis of T cells from PBMC and DP showed bb21217 DP is significantly enriched for memory-like T cells (LEF1+, CD27+, CCR7+) and depleted of highly differentiated or senescent CD57+ T cells. Patients with DPs most enriched for early memory markers (LEF1+, CCR7+ and CD27+) and with low expression of effector/exhaustion markers (EOMES+, GZMA+, CD57+) were more likely to have higher peak CAR+ T cell expansion. To evaluate the association of these DP markers with DOR, we split the 24 responders (≥PR) on median marker expression (high vs low) and analyzed DOR in these exploratory subgroups. High CD127 expression, associated with long-lasting memory T cell formation, was positively correlated with DOR, while multiple markers associated with differentiated T cells (e.g. EOMES+, TBET+) were negatively correlated with DOR. Conclusions: The adverse events observed are consistent with known toxicities of CAR T cell therapies. Initial efficacy results with bb21217 are encouraging, with 48% of patients treated across target dose levels of 150-450 obtaining ≥VGPR. The presence of T cell markers associated with memory and the absence of T cells markers associated with differentiation/senescence in DP correlated positively with peak expansion and DOR. These preliminary correlative data support the mechanistic hypothesis that enrichment for memory like T cells in bb21217 DP may result in improved clinical outcomes. Data for approximately 14 additional patients at the 450 target dose will be presented. Disclosures Alsina: Janssen: Honoraria, Speakers Bureau; Celgene: Consultancy, Honoraria; Amgen: Honoraria, Speakers Bureau; BMS: Consultancy, Research Funding. Shah:GSK, Amgen, Indapta Therapeutics, Sanofi, BMS, CareDx, Kite, Karyopharm: Consultancy; BMS, Janssen, Bluebird Bio, Sutro Biopharma, Teneobio, Poseida, Nektar: Research Funding. Raje:Janssen: Consultancy; Celgene: Consultancy; Immuneel: Membership on an entity's Board of Directors or advisory committees; Caribou: Membership on an entity's Board of Directors or advisory committees; Takeda: Consultancy; Astrazeneca: Consultancy; Bluebird, Bio: Consultancy, Research Funding; Karyopharm: Consultancy; BMS: Consultancy; Amgen: Consultancy. Jagannath:Karyopharm: Consultancy, Honoraria; Legend Biotech: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; BMS: Consultancy, Honoraria. Madduri:Janssen: Consultancy; BMS: Consultancy; Takeda: Consultancy; Legend: Consultancy; Sanofi: Consultancy; GSK: Consultancy; Kinevant: Consultancy; Foundation Medicine: Consultancy. Kaufman:Janssen: Consultancy, Honoraria; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Tecnopharma: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; AbbVie: Consultancy; TG Therapeutics: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Bristol-Myers Squibb: Consultancy, Honoraria; Incyte: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi/Genyzme: Consultancy, Honoraria. Siegel:Amgen: Consultancy, Honoraria, Speakers Bureau; Merck: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Speakers Bureau; Takeda: Consultancy, Honoraria, Speakers Bureau; Karyopharma: Consultancy, Honoraria; Celulatiry: Consultancy. Munshi:BMS: Consultancy; OncoPep: Consultancy, Current equity holder in private company, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties; C4: Current equity holder in private company; Janssen: Consultancy; Adaptive: Consultancy; Legend: Consultancy; Amgen: Consultancy; AbbVie: Consultancy; Karyopharm: Consultancy; Takeda: Consultancy. Lin:Novartis: Consultancy; Celgene: Consultancy, Research Funding; Bluebird Bio: Consultancy, Research Funding; Juno: Consultancy; Legend BioTech: Consultancy; Merck: Research Funding; Takeda: Research Funding; Gamida Cells: Consultancy; Sorrento: Consultancy, Membership on an entity's Board of Directors or advisory committees; Vineti: Consultancy; Janssen: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding. Jakubowiak:AbbVie, Amgen, BMS/Celgene, GSK, Janssen, Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive, Juno: Consultancy, Honoraria. Timm:bluebird bio: Current Employment, Current equity holder in publicly-traded company. Turka:bluebird bio: Current Employment. Mao:bluebird bio: Current Employment, Current equity holder in publicly-traded company. Martin:BMS: Current Employment, Current equity holder in publicly-traded company. Campbell:BMS: Current Employment, Current equity holder in publicly-traded company. Hege:Arcus Biosciences: Divested equity in a private or publicly-traded company in the past 24 months; Mersana Therapeutics: Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; BMS: Current Employment, Current equity holder in publicly-traded company, Other: Travel, accommodations, expenses, Patents & Royalties: Numerous, Research Funding. Bitter:Novartis AG, Predicant Biosciences, Biospect, F Hofmann-La Roche: Ended employment in the past 24 months; bluebird bio: Current Employment, Current equity holder in publicly-traded company; Novartis: Ended employment in the past 24 months, Patents & Royalties. Petrocca:bluebird, bio: Current Employment, Current equity holder in publicly-traded company. Berdeja:Celgene: Consultancy, Research Funding; Cellularity: Research Funding; Constellation: Research Funding; CRISPR Therapeutics: Consultancy, Research Funding; CURIS: Research Funding; EMD Sorono: Research Funding; Takeda: Consultancy, Research Funding; Servier: Consultancy; Teva: Research Funding; Prothena: Consultancy; Poseida: Research Funding; Novartis: Research Funding; Lilly: Research Funding; Legend: Consultancy; Kite Pharma: Consultancy; Kesios: Research Funding; Karyopharm: Consultancy; Janssen: Consultancy, Research Funding; Glenmark: Research Funding; Genentech, Inc.: Research Funding; BMS: Consultancy, Research Funding; Bioclinica: Consultancy; Bluebird: Research Funding; Acetylon: Research Funding; Amgen: Consultancy, Research Funding; Abbvie: Research Funding; Vivolux: Research Funding.

AbstractWe studied 2,528 patients with upfront autologous haematopoietic cell transplantation (AHCT) for multiple myeloma (MM) from 2008–2017 to develop a prognostic model to predict outcomes. High‐risk cytogenetics included t(4;14), t(14;16), t(14;20), del13q on karyotype, del17p, +1q or 1pdel. A Cox model identified factors prognostic of progression/relapse in a training subset (n = 1,246). A weighted score using these factors was assigned to a validation cohort (n = 774). Presence of high‐risk cytogenetics [hazard ratio, (HR) 1·68 (1·3–2·17)] and pre‐AHCT bone marrow plasma cells (BMPCs) ≥10% [1·68 (1·33–2·12)] were assigned 4 points each; albumin at diagnosis <3·5 g/dl [1·31 (1·07–1·61)] 2; standard risk cytogenetics 1, and no cytogenetics abnormality, BMPCs <10% at AHCT and albumin ≥3·5 g/dl at diagnosis 0 points each. A three‐category system with low risk (0–3), intermediate risk (4–8) and high risk (9–10) showed 3‐year progression‐free survival in the low vs. intermediate vs. high risk of 58% (95% CI: 52–63) vs. 49% (95% CI: 43–56) vs. 31% (95% CI: 12–51), P < 0.001 respectively, and 3‐year OS in low vs. intermediate vs. high risk of 88% (95% CI: 84–91) vs. 81% (95% CI: 76–86) vs. 64% (95% CI: 39–80); P < 0·001. Our prognostic scoring system can identify MM patients at risk for early relapse after AHCT.

Abstract Background Dysphagia is prevalent with cerebrovascular accidents and contributes to the burden of disease and mortality. Strengthening dysfunctional swallow muscles through respiratory muscle training (RMT) has proven effective in improving swallow effectiveness and safety. However, approaches to strengthen only the expiratory muscle groups (EMST) dominate the clinical study literature, with variable outcomes. This study investigated the effect of simultaneous inspiratory‐expiratory muscle strengthening to improve swallowing function in stroke patients. Methods Recorded data of 20 patients receiving pro bono medical care for dysphagia following stroke were allocated to intervention (IG) or control group (CG) based upon whether they chose combined RMT (cRMT) or not while awaiting swallow therapy services. The intervention group was treated with three 5‐minute sessions of resistive respiratory muscle training for 28 days, while the control group received no RMT or other exercise intervention. Respiratory and swallow outcomes were assessed pre‐ and post‐intervention and included Mann Assessment of Swallowing Ability (MASA), fiberoptic endoscopic evaluation of swallowing (FEES) with penetration‐aspiration scale (PAS), functional oral intake scale (FOIS), patient visual analogue scale (VAS), and peak expiratory flow (PEF). Results After 28 days, the intervention group demonstrated greater improvements ( P value < 0.05) in PEF (IG: 168.03% vs CG: 17.47%), VAS (IG: 103.85% vs CG: 27.54%), MASA (IG: 37.28% vs CG: 6.92%), PAS (IG: 69.84% vs CG: 12.12%), and FOIS (IG: 93.75% vs CG: 21.21%). Conclusion cRMT is a feasible and effective method to improve signs and symptoms of dysphagia while improving airway protection. Level of Evidence 3

BackgroundMultiple myeloma (MM) with the translocation t(11;14) may have inferior outcomes in comparison with other standard‐risk MM, and it has been suggested to portend a worse prognosis in African Americans in comparison with Whites. This study used the Center for International Blood and Marrow Transplant Research (CIBMTR) database to examine the impact of t(11;14) on the clinical outcomes of patients with MM of African American and White descent.MethodsThis study evaluated 3538 patients who underwent autologous hematopoietic cell transplantation (autoHCT) for MM from 2008 to 2016 and were reported to the CIBMTR. Patients were analyzed in 4 groups: African Americans with t(11;14) (n = 117), African Americans without t(11;14) (n = 968), Whites with t(11;14) (n = 266), and Whites without t(11;14) (n = 2187).ResultsAfrican Americans with t(11;14) were younger, had lower Karnofsky scores, and had more advanced stage MM with a higher Hematopoietic Cell Transplantation–Comorbidity Index (HCT‐CI). Fewer African Americans with t(11;14) (21%) had a coexistent high‐risk marker in comparison with Whites with t(11;14) (27%). In a multivariate analysis, race and t(11;14) had no association with progression‐free survival. However, overall survival was superior among African Americans with t(11;14) in comparison with Whites with t(11;14) (hazard ratio, 0.53; 95% confidence interval, 0.30‐0.93; P = .03). Survival was also associated with female sex, stage, time from diagnosis to transplant, a low HCT‐CI, and receipt of maintenance.ConclusionsRace may have a differential impact on the survival of patients with t(11;14) MM who undergo autoHCT and needs to be further studied.