Usmani, Saad Z.

Abstract Introduction: In oncology clinical trials, overall survival (OS) is considered the gold standard efficacy endpoint. However, in multiple myeloma, the prolonged survival times and availability of multiple salvage therapies render it difficult to rely on OS as a primary endpoint. Instead, progression-free survival (PFS) or clinical response can be a relevant biomarker. At the same time, some health technology assessment bodies will only consider evidence based on patient-relevant endpoints, such as morbidity, mortality, and health-related quality of life (HRQoL), within their benefit assessments. Patient-reported outcomes (PROs) provide insights into how a treatment affects HRQoL, including symptoms and functioning. In the phase 3 MAIA trial, daratumumab, lenalidomide, and dexamethasone (D-Rd) demonstrated a significantly prolonged PFS and rapid and sustained improvements in PROs compared with lenalidomide and dexamethasone (Rd) alone at a median follow-up of 28 months. Updated results with longer follow-up confirmed a continued PFS benefit, deepening best clinical responses, and a significant OS benefit with D-Rd. Here, we report the results of analyses exploring the relationship between clinical efficacy endpoints and PROs in the MAIA trial. Methods: In MAIA (NCT02252172), TIE patients with NDMM were randomized to D-Rd or Rd until disease progression (PD) or unacceptable side effects. Clinical response and PD were defined per the International Myeloma Working Group uniform response criteria. PROs were assessed at baseline, on day 1 of cycles 3, 6, 9, and 12 for year 1, every 6 months thereafter until PD, or at end of treatment and at 8 and 16 weeks post-progression using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item (EORTC QLQ-C30). The current analyses were conducted on patients with a baseline PRO assessment and ≥1 post-baseline PRO assessment using a clinical cutoff date of February 19, 2021. Patients from both treatment groups were pooled and stratified by best clinical response. For PROs, the threshold for clinically meaningful change from baseline was defined a priori as ≥10 points based on published literature. Analyses were conducted for the global health status (GHS), fatigue, and pain scales of the EORTC QLQ-C30. The proportions of patients with clinically meaningful improvement in these PROs from baseline at any time while on treatment were calculated for and compared across best clinical response subgroups. For this analysis, patients were censored at the time of PD or discontinuation of therapy. Results were summarized with odds ratios and 95% confidence intervals. Additionally, the proportions of patients with clinically meaningful worsening in PROs from baseline at the time of and post-progression were also calculated for those who had PD. No adjustments were made for multiplicity. Nominal P-values are presented. Results: Best clinical response at a median follow-up of 56.2 months for the 710 patients included in this analysis is shown in the Table. For GHS, fatigue, and pain, the proportion of patients who reported clinically meaningful improvement from baseline increased with increasing depth of best clinical response. Odds ratios comparing best clinical response vs stable disease reflect this relationship and are shown in the Figure. Of the 264 patients who experienced PD and had PRO data at the time of or post-progression, 38.6%, 54.9%, and 39.4% reported meaningful worsening of GHS, pain, and fatigue, respectively, at the time of or post-progression. Conclusions: Patients with deeper best clinical response were more likely to report meaningful improvements in PROs. Patients who experienced PD reported worsening of GHS and symptoms at the time of or following progression. These analyses provide evidence of the association between key clinical efficacy endpoints and PROs and demonstrate the patient relevance of these clinical endpoints. Figure 1 Figure 1. Disclosures Perrot: Abbvie: Honoraria; BMS Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Honoraria, Research Funding; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Kumar: Amgen: Consultancy, Research Funding; BMS: Consultancy, Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche-Genentech: Consultancy, Research Funding; Bluebird Bio: Consultancy; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Carsgen: Research Funding; Antengene: Consultancy, Honoraria; Oncopeptides: Consultancy; Beigene: Consultancy; Tenebio: Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding. Plesner: Takeda: Research Funding; Genentech: Other: Advisor, Research Funding; Oncopeptides: Other: Advisor, Research Funding; AbbVie: Other: Advisor, Research Funding; CSL Behring: Other: Advisor; Janssen: Other: Advisor, Research Funding; Celgene: Other: Advisor, Research Funding; Genmab: Research Funding. Orlowski: Asylia Therapeutics, Inc., BioTheryX, Inc., and Heidelberg Pharma, AG.: Other: Laboratory research funding; CARsgen Therapeutics, Celgene, Exelixis, Janssen Biotech, Sanofi-Aventis, Takeda Pharmaceuticals North America, Inc.: Other: Clinical research funding; Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, EcoR1 Capital LLC, Genzyme, GSK Biologicals, Janssen Biotech, Karyopharm Therapeutics, Inc., Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, Inc., Sanofi-Aventis, and Takeda P: Consultancy, Honoraria; Asylia Therapeutics, Inc.: Current holder of individual stocks in a privately-held company, Patents & Royalties; Amgen, Inc., BioTheryX, Inc., Bristol-Myers Squibb, Celgene, Forma Therapeutics, Genzyme, GSK Biologicals, Janssen Biotech, Juno Therapeutics, Karyopharm Therapeutics, Inc., Kite Pharma, Neoleukin Corporation, Oncopeptides AB, Regeneron Pharmaceuticals, I: Membership on an entity's Board of Directors or advisory committees. Moreau: Abbvie: Honoraria; Oncopeptides: Honoraria; Celgene BMS: Honoraria; Sanofi: Honoraria; Amgen: Honoraria; Janssen: Honoraria. Bahlis: Amgen: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; BMS/Celgene: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Genentech: Consultancy; GlaxoSmithKline: Consultancy, Honoraria. Nahi: XNK Therapeutics AB: Consultancy. Hulin: abbvie: Honoraria; Celgene/BMS: Honoraria; Sanofi: Honoraria; Takeda: Honoraria; Janssen: Honoraria. Quach: Bristol Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; CSL: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen/Cilag: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Antengene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Goldschmidt: GSK: Honoraria; Incyte: Research Funding; Janssen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Amgen: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; BMS: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Adaptive Biotechnology: Consultancy; Celgene: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Chugai: Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Novartis: Honoraria, Research Funding; Dietmar-Hopp-Foundation: Other: Grant; Sanofi: Consultancy, Honoraria, Other: Grants and/or Provision of Investigational Medicinal Product, Research Funding; Takeda: Consultancy, Research Funding; Johns Hopkins University: Other: Grant; Mundipharma: Research Funding; MSD: Research Funding; Molecular Partners: Research Funding. O'Dwyer: Bristol Myers Squibb: Research Funding; ONK Therapeutics: Current Employment, Current equity holder in publicly-traded company, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy. Venner: Amgen: Research Funding; Celgene: Research Funding; Takeda: Honoraria; Amgen: Honoraria; Janssen: Honoraria; BMS: Honoraria; Sanofi: Honoraria; Pfizer: Honoraria. Weisel: Adaptive Biotechnologies: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol Myers Squibb: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche: Honoraria; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Oncopeptides: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Abbvie: Consultancy; Novartis: Honoraria; Pfizer: Honoraria. Raje: Celgene, Amgen, Bluebird Bio, Janssen, Caribou, and BMS: Other. Macro: Takeda: Honoraria, Other: Travel accomodation, Research Funding; Janssen: Honoraria, Other: Travel accomodation, Research Funding; GSK: Honoraria; Celgen/BMS: Honoraria; Sanofi: Honoraria. Leleu: Sanofi: Honoraria; Roche: Honoraria; Pierre Fabre: Honoraria; Oncopeptides: Honoraria; Novartis: Honoraria; Mundipharma: Honoraria; Merck: Honoraria; Karyopharm Therapeutics: Honoraria; Amgen: Honoraria; Bristol-Myers Squibb: Honoraria; Carsgen Therapeutics Ltd: Honoraria; Celgene: Honoraria; Gilead Sciences: Honoraria; Janssen-Cilag: Honoraria; AbbVie: Honoraria; Takeda: Honoraria, Other: Non-financial support. Liu: Janssen: Current Employment, Current equity holder in publicly-traded company. Fastenau: Janssen: Current Employment, Current equity holder in publicly-traded company. Gries: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Ho: DRG Abacus: Consultancy; Emalex Biosciences: Consultancy; Janssen: Consultancy. Mistry: Janssen: Current Employment, Current equity holder in publicly-traded company. Tromp: Janssen: Current Employment, Current equity holder in publicly-traded company. Delioukina: Janssen: Current Employment. Vermeulen: Janssen: Current Employment, Current equity holder in publicly-traded company. Usmani: Amgen: Consultancy, Research Funding, Speakers Bureau; Abbvie: Consultancy; Array BioPharma: Consultancy, Research Funding; GSK: Consultancy, Research Funding; EdoPharma: Consultancy; SkylineDX: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; Takeda: Consultancy, Research Funding, Speakers Bureau; Seattle Genetics: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Janssen: Consultancy, Research Funding, Speakers Bureau; Sanofi: Consultancy, Research Funding, Speakers Bureau; Janssen Oncology: Consultancy, Research Funding; Bristol-Myers Squibb: Research Funding.

Abstract Background: MM that is refractory to a proteasome inhibitor (PI), an immunomodulatory agent (IMiD) and an anti-CD38 monoclonal antibody (CD38MoAb) is labeled triple-class refractory (TCR) and recognized as a modern therapeutic challenge. In recent years, new agents have shown activity in this setting in single arm trials and many more are in development. The assessment of the impact of new agents in the TCR setting is impaired by limited information on the therapeutic outcomes of these patients when treated with non-investigational therapies. Methods: We utilized an independent RWD dataset of patients with MM refractory to CD38MoAb built from academic collaboration (MAMMOTH study) to identify patients with TCR MM who received subsequent therapy. Patients with MM that was CD38MoAb refractory but not TCR were followed longitudinally and only included if, after subsequent lines of therapy, MM became TCR. Patients were excluded if they had plasma cell leukemia, poor renal function (serum creatinine > 2 mg/dl) or if next therapy after TCR status included experimental agents. Refractoriness to a MM agent was defined as lack of objective response and/or progression while receiving therapy or within 60 days of last dose as per International Myeloma Working Group (IMWG) criteria. Time zero for analysis was initiation of next therapy after MM became TCR. Response to therapy and progression were adjudicated utilizing IMWG criteria. MM that was TCR but also exposed to 2 PIs, 2 IMiDs and a CD38MoAb was considered penta-exposed, and when refractory to 2 PIs, 2 IMiDs and a CD38MoAb, it was considered penta-refractory. Results: Data collection occurred between 2016 and 2018 (prior to commercial availability of selinexor, belantamab mafodotin, melflufen or ide-cel). Of 275 patients in the MAMMOTH study, 177 were included. Median age was 65 years (range 27-90), 53% were male, 76% white, 28 % had International Staging System stage 3, and 29% high risk cytogenetics [t(4;14), t(14;16) or del(17p)]. Median number of prior lines of therapy was 5 (range 3-17), median time from diagnosis to TCR was 4.8 years (range 0.9-19.4), 73% had received prior autologous hematopoietic cell transplantation, 84% were refractory to bortezomib or ixazomib, 58% were refractory to carfilzomib, 87% to lenalidomide and 74% to pomalidomide. Penta-exposed patients were 58% and penta-refractory 30%. The first regimen after MM became TCR included cytotoxic chemotherapy in 45%, CD38MoAb in 25%, SLAMF7 MoAb in 7%, carfilzomib in 24%, and pomalidomide in 34% of cases. Overall response rate (ORR) was 30% (20.9% PR, 7.3% VGPR and 1.7% CR). Median progression-free survival (PFS) was 2.8 mo. (95% C.I. 2.3-3.2) and overall survival (OS) 8.6 mo. (95% C.I. 6.8-10.3),(Figure). For Patients with MM that was penta-exposed (N=102), ORR was 30%, median PFS was 2.7 mo (95% C.I 2.1-3.2), and median OS 7.7 mo (95% C.I. 6.0-9.4). For patients with penta-refractory MM (N=53), ORR was 32%, median PFS was 2.5 mo. (95% C.I. 1.7-3.3), and median OS 6.9 mo. (95% C.I. 4.9-8.9). PFS or OS was similar among patients who were TCR but not penta-exposed, TCR plus penta-exposed but not penta- refractory or TCR plus penta-refractory (Figure). Outcomes according to next regimen after MM became TCR are outlined in the Table. In multivariable analysis, no factor was predictor of PFS while refractoriness to carfilzomib (HR 2.2, 95% C.I. 1.5-3.3), presence of high-risk chromosome abnormalities (HR 1.5, 95% C.I. 1.0-2.2) and short interval from diagnosis to TCR (HR 0.92, 95% C.I. 0.85-0.99) were predictors of shorter OS. Conclusions: Patients with TCR MM have a uniformly low chance of response to subsequent conventional therapy with short PFS and OS even when not penta-exposed or penta-refractory. This dataset provides efficacy benchmark for new therapies being developed in this setting. Figure 1 Figure 1. Disclosures Costa: BMS: Consultancy, Honoraria, Research Funding; Karyopharm: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria, Speakers Bureau; Janssen: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau. Cornell: Abvvie: Current Employment. Chhabra: GSK: Honoraria. Liedtke: Janssen Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Caelum: Membership on an entity's Board of Directors or advisory committees, Other: Clinical Trial Funding; Bristol Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Kite: Membership on an entity's Board of Directors or advisory committees; Kura Oncology: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Pfizer: Honoraria; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Alnylam: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees. Kansagra: GSK: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Pfizer: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Cota Health: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Alynylam: Membership on an entity's Board of Directors or advisory committees. Giri: PackHealth: Research Funding; CareVive: Honoraria, Research Funding. Malek: Amgen: Honoraria; Janssen: Other: Advisory board ; Cumberland Inc.: Research Funding; Bluespark Inc.: Research Funding; BMS: Honoraria, Research Funding; Sanofi: Other: Advisory Board; Medpacto Inc.: Research Funding; Takeda: Honoraria. Vij: BMS: Research Funding; Takeda: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; BMS: Honoraria; GSK: Honoraria; Oncopeptides: Honoraria; Karyopharm: Honoraria; CareDx: Honoraria; Legend: Honoraria; Biegene: Honoraria; Adaptive: Honoraria; Harpoon: Honoraria. Usmani: Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; Array BioPharma: Consultancy, Research Funding; Amgen: Consultancy, Research Funding, Speakers Bureau; Abbvie: Consultancy; EdoPharma: Consultancy; GSK: Consultancy, Research Funding; Janssen: Consultancy, Research Funding, Speakers Bureau; Sanofi: Consultancy, Research Funding, Speakers Bureau; Merck: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; SkylineDX: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Takeda: Consultancy, Research Funding, Speakers Bureau; Janssen Oncology: Consultancy, Research Funding; Bristol-Myers Squibb: Research Funding. Hari: Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Adaptive Biotech: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Karyopharm: Consultancy; Celgene-BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau. Kumar: Adaptive: Membership on an entity's Board of Directors or advisory committees, Research Funding; Merck: Research Funding; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Carsgen: Research Funding; Novartis: Research Funding; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Roche-Genentech: Consultancy, Research Funding; Bluebird Bio: Consultancy; Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Tenebio: Research Funding; Antengene: Consultancy, Honoraria; Beigene: Consultancy; Oncopeptides: Consultancy; Sanofi: Research Funding.

Abstract Introduction: Ciltacabtagene autoleucel (cilta-cel), a chimeric antigen receptor T-cell (CAR-T) therapy with 2 B-cell maturation antigen (BCMA)-targeting single-domain antibodies, is being evaluated in patients (pts) with relapsed/refractory multiple myeloma (RRMM). In the phase 1b/2 CARTITUDE-1 (NCT03548207) study, a single dose of cilta-cel led to early, deep, and durable responses in heavily pretreated pts with MM, with a manageable safety profile (Berdeja, Lancet, 2021). At median 18 months of follow-up, the overall response rate (ORR) was 98%, with 80% of pts achieving stringent complete response. Median duration of response (DOR) was 21.8 months (95% CI, 21.8-not estimable); 18-month progression-free survival (PFS) and overall survival (OS) rates were 66% and 81%, respectively. Here, we report the efficacy and safety of cilta-cel in various subgroups of pts in CARTITUDE-1. Methods: Eligible pts had MM and received ≥3 prior lines of therapy (LOT) or were double refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD), and had received a PI, IMiD, and anti-CD38 antibody. After apheresis, bridging therapy was permitted. Pts received a single cilta-cel infusion (target dose: 0.75×10 6 CAR+ viable T cells/kg; range 0.5-1.0×10 6) 5-7 days after lymphodepletion (300 mg/m 2 cyclophosphamide, 30 mg/m 2 fludarabine daily for 3 days). Primary objectives were to characterize cilta-cel safety, confirm the recommended phase 2 dose (phase 1b), and evaluate efficacy (phase 2). In this combined phase 1b and phase 2 analysis, cytokine release syndrome (CRS) graded by Lee et al (Blood 2014) criteria and neurotoxicity by CTCAE v5.0 were mapped to the ASTCT criteria for CRS and immune effector cell-associated neurotoxicity (ICANS), respectively. Efficacy and safety were evaluated in the following subgroups: ≥65 years of age, Black/African American, 3 prior LOT, ≥4 prior LOT, triple-class refractory, penta-drug refractory, standard- and high-risk cytogenetics, International Staging System stage III, bone marrow plasma cells at baseline (≤30%, >30 to <60%, and ≥60%), BCMA tumor expression at baseline (<80%, ≥80%), and presence of soft tissue plasmacytomas (bone-based and extramedullary). Results: As of February 11, 2021, 97 pts in the overall population received cilta-cel; 58.8% were male, median age was 61 years (range 43-78), and median time from diagnosis to enrollment was 5.9 years (range 1.6-18.2). ORR across all evaluated subgroups was comparable to the overall population, and was consistently high (range 95.1-100%) including in those with high-risk cytogenetics, ISS stage III MM, baseline bone marrow cells ≥60%, and baseline plasmacytomas (Table). Median DOR for most subgroups, including high-risk cytogenetics, was consistent with the overall population or not reached but was shorter in pts with ISS Stage III MM and baseline plasmacytomas (Table). Across all subgroups, 80%-100% of MRD-evaluable pts achieved MRD negativity (10 -5 threshold). 18-month PFS and OS rates were consistent with the overall population in most subgroups, including high-risk cytogenetics, and lower in ISS stage III and baseline plasmacytomas (Table). Incidence of CRS, ICANS, and other CAR T-cell neurotoxicities (events not reported as ICANS [ie, onset after a period of recovery from CRS and ICANS]) in various subgroups was consistent with the overall population, with no new safety signals. Conclusions: At median follow-up of 18 months, a single infusion of cilta-cel yielded deep, durable responses in all evaluated subgroups in CARTITUDE-1. An ORR of 95%-100% was observed in pts across all subgroups, including those with high-risk cytogenetics, ISS stage III MM, baseline bone marrow cells ≥60%, and baseline plasmacytomas. In patients with ISS stage III and with baseline plasmacytomas, median DOR appeared shorter and 18-mo PFS and OS rates lower. Cilta-cel safety profile across the subgroups was consistent with the overall population, with no new safety signals. Ongoing evaluation of cilta-cel in the multicohort CARTITUDE-2 (NCT04133636) study in pts with unmet need in varying stages of treatment for MM will further explore the treatment benefit of cilta-cel, including in those with high-risk disease. Figure 1 Figure 1. Disclosures Jakubowiak: GSK: Membership on an entity's Board of Directors or advisory committees; Abbvie: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; BMS: Membership on an entity's Board of Directors or advisory committees; Gracell: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Usmani: Janssen Oncology: Consultancy, Research Funding; Takeda: Consultancy, Research Funding, Speakers Bureau; SkylineDX: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding, Speakers Bureau; Amgen: Consultancy, Research Funding, Speakers Bureau; Merck: Consultancy, Research Funding; Janssen: Consultancy, Research Funding, Speakers Bureau; Array BioPharma: Consultancy, Research Funding; GSK: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; EdoPharma: Consultancy; Abbvie: Consultancy; Bristol-Myers Squibb: Research Funding. Berdeja: Bluebird bio, BMS, Celgene, CRISPR Therapeutics, Janssen, Kite Pharma, Legend Biotech, SecuraBio, Takeda: Consultancy; GSK, Ichnos Sciences, Incyte: Research Funding; EMD Sorono, Genentech: Research Funding; Celularity, CRISPR Therapeutics: Research Funding; Lilly, Novartis: Research Funding; Abbvie, Acetylon, Amgen: Research Funding; Poseida, Sanofi, Teva: Research Funding. Cohen: Oncopeptides: Consultancy; Genentech/Roche: Consultancy; Janssen: Consultancy; BMS/Celgene: Consultancy; Takeda: Consultancy; GlaxoSmithKline: Consultancy, Research Funding; AstraZeneca: Consultancy; Novartis: Research Funding. Hari: Karyopharm: Consultancy; Adaptive Biotech: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Takeda: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Celgene-BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau. Schecter: Janssen: Current Employment, Current holder of stock options in a privately-held company. Yeh: Janssen: Current Employment. Olyslager: Janssen: Current Employment. Banerjee: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Jackson: Janssen: Current Employment; Memorial Sloan Kettering Cancer Center: Consultancy. Allred: Janssen: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Zudaire: Janssen: Current Employment. Deraedt: Janssen: Current Employment. Geng: Legend Biotech USA: Current Employment. Pacaud: Legend Biotech: Current Employment. Lin: Janssen: Consultancy, Research Funding; Vineti: Consultancy; Legend: Consultancy; Bluebird Bio: Consultancy, Research Funding; Novartis: Consultancy; Juno: Consultancy; Celgene: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Takeda: Research Funding; Sorrento: Consultancy; Merck: Research Funding; Gamida Cell: Consultancy. Martin: Janssen: Research Funding; GlaxoSmithKline: Consultancy; Oncopeptides: Consultancy; Amgen: Research Funding; Sanofi: Research Funding. Jagannath: Bristol Myers Squibb: Consultancy; Janssen Pharmaceuticals: Consultancy; Legend Biotech: Consultancy; Karyopharm Therapeutics: Consultancy; Takeda: Consultancy; Sanofi: Consultancy. OffLabel Disclosure: At the time of abstract submission, cilta-cel is being investigated for the treatment of multiple myeloma but is not yet approved.

Abstract We explored minimal residual disease (MRD) in relapsed/refractory multiple myeloma (RRMM) and transplant-ineligible (TIE) newly diagnosed multiple myeloma (NDMM) using data from 4 phase 3 studies (POLLUX, CASTOR, ALCYONE, and MAIA). Each study previously demonstrated that daratumumab-based therapies improved MRD negativity rates and reduced the risk of disease progression or death by approximately half vs standards of care. We conducted a large-scale pooled analysis for associations between patients achieving complete response or better (≥CR) with MRD-negative status and progression-free survival (PFS). MRD was assessed via next-generation sequencing (10−5 sensitivity threshold). Patient-level data were pooled from all 4 studies and for patients with TIE NDMM and patients with RRMM who received ≤2 prior lines of therapy (≤2 PL). PFS was evaluated by response and MRD status. Median follow-up (months) was 54.8 for POLLUX, 50.2 for CASTOR, 40.1 for ALCYONE, and 36.4 for MAIA. Patients who achieved ≥CR and MRD negativity had improved PFS vs those who failed to reach CR or were MRD positive (TIE NDMM and RRMM hazard ratio [HR] 0.20, P < .0001; TIE NDMM and RRMM ≤2 PL HR 0.20, P < .0001). This benefit occurred irrespective of therapy or disease setting. A time-varying Cox proportional hazard model confirmed that ≥CR with MRD negativity was associated with improved PFS. Daratumumab-based treatment was associated with more patients reaching ≥CR and MRD negativity. These findings represent the first large-scale analysis with robust methodology to support ≥CR with MRD negativity as a prognostic factor for PFS in RRMM and TIE NDMM. These trials were registered at www.clinicaltrials.gov as #NCT02076009, #NCT02136134, #NCT02195479, and #NCT02252172.

Abstract In patients with transplant-ineligible newly diagnosed multiple myeloma (NDMM), daratumumab reduced the risk of disease progression or death by 44% in MAIA (daratumumab/lenalidomide/dexamethasone [D-Rd]) and 58% in ALCYONE (daratumumab/bortezomib/melphalan/prednisone [D-VMP]). Minimal residual disease (MRD) is a sensitive measure of disease and response to therapy. MRD-negativity status and durability were assessed in MAIA and ALCYONE. MRD assessments using next-generation sequencing (10−5) occurred for patients achieving complete response (CR) or better and after at least CR at 12, 18, 24, and 30 months from the first dose. Progression-free survival (PFS) by MRD status and sustained MRD negativity lasting ≥6 and ≥12 months were analyzed in the intent-to-treat population and among patients achieving at least CR. In MAIA (D-Rd, n = 368; lenalidomide and dexamethasone [Rd], n = 369) and ALCYONE (D-VMP, n = 350; bortezomib/melphalan/prednisone [VMP], n = 356), the median duration of follow-up was 36.4 and 40.1 months, respectively. MRD-negative status and sustained MRD negativity lasting ≥6 and ≥12 months were associated with improved PFS, regardless of treatment group. However, daratumumab-based therapy improved rates of MRD negativity lasting ≥6 months (D-Rd, 14.9% vs Rd, 4.3%; D-VMP, 15.7% vs VMP, 4.5%) and ≥12 months (D-Rd, 10.9% vs Rd, 2.4%; D-VMP, 14.0% vs VMP, 2.8%), both of which translated to improved PFS vs control groups. In a pooled analysis, patients who were MRD negative had improved PFS vs patients who were MRD positive. Patients with NDMM who achieved MRD-negative status or sustained MRD negativity had deep remission and improved clinical outcomes. These trials were registered at www.clinicaltrials.gov as #NCT02252172 (MAIA) and #NCT02195479 (ALCYONE).

8030 Background: CARTITUDE-1 is a single arm study of Ciltacabtagene autoleucel (cilta-cel; JNJ-68284528) anti-BCMA CAR-T cell therapy in US patients (pts) with relapsed multiple myeloma (RRMM) refractory to both IMiD and proteasome inhibitor (PI) or with at least 3 prior lines of therapy and previously exposed to anti-CD38 monoclonal antibody (MoAb). While recently reported efficacy results of cilta-cel were encouraging, it is unknown how they compare with similar pts receiving conventional (non CAR-T) treatment. Methods: We utilized a contemporary US-based dataset of pts with MM refractory to anti-CD38 MoAb (MAMMOTH) to identify pts who would meet eligibility for CARTITUDE-1 and who received conventional therapy. We analyzed the intent-to-treat population (ITT) in CARTITUDE-1, defined as pts who underwent apheresis (N=113) and a modified ITT population (mITT) defined as subset of pts who received cilta-cel at the RP2D (N=97). From the MAMMOTH dataset, we identified a population corresponding to CARTITUDE-1 ITT (N=190) and a mITT population, pts without death or progression within 47 days (median time between apheresis and cilta-cel infusion) from onset of therapy (N=122). We calculated propensity scores (PS) with demographics, N of prior therapies, cytogenetics and refractoriness to MM agents as covariates. An analyst blinded to outcomes performed nearest neighbor 1:1 PS matching. We analyzed overall response rate (ORR), progression-free (PFS) and overall survival (OS) for ITT and mITT in CARTITUDE-1 vs matching MAMMOTH cohorts. Results: Ninety-five ITT (75 received bridging therapy, 82 received cilta-cel) and 69 mITT (54 received bridging) CARTITUDE-1 pts matched MAMMOTH pts (Table). Among the pts in the MAMMOTH ITT cohort 34% received pomalidomide, 24% anti-CD38 MoAb, 19% carfilzomib and 35% cytotoxic chemotherapy in next therapy. ORR in the ITT cohorts was higher in CARTITUDE-1 (84% vs. 28%). Compared to their MAMMOTH counterparts, pts in CARTITUDE-1 ITT cohort had improved PFS (12 mo. 73% vs. 12%) and OS (12 mo. 83% vs 39%). Between the mITT cohorts, CARTITUDE-1 pts had superior ORR (96% vs. 30%), PFS (12 mo 79% vs. 15%) and OS (12 mo. 88% vs. 41%). Conclusions: In pts with RRMM beyond therapy with IMID, PI, and anti-CD38 MoAb, treatment with cilta-cel is associated with higher response rate and superior PFS and OS when compared to conventional treatment.[Table: see text]

8005 Background: CARTITUDE-1 (NCT03548207) is a phase 1b/2 study evaluating ciltacabtagene autoleucel (cilta-cel; JNJ-68284528), a CAR T-cell therapy with two BCMA–targeting single-domain antibodies, in patients (pts) with R/R MM. Here, we report updated results in pts with a longer duration (median 12.4 months) of follow-up. Methods: Eligible pts had MM and received ≥3 prior regimens or were double refractory to a proteasome inhibitor (PI) and immunomodulatory drug (IMiD), and had received a PI, IMiD, and anti-CD38 antibody. After apheresis, bridging therapy was permitted. Pts received a single cilta-cel infusion (target dose: 0.75×106 CAR+ viable T cells/kg; range 0.5-1.0×106) 5–7 days (d) after lymphodepletion (300 mg/m2 cyclophosphamide, 30 mg/m2 fludarabine daily for 3 d). The primary objectives were to characterize cilta-cel safety, confirm the recommended phase 2 dose (RP2D; phase 1b), and evaluate efficacy (phase 2). Cytokine release syndrome (CRS) was graded by Lee et al (Blood 2014) and neurotoxicity by CTCAE, v5.0 (in phase 1b). CRS and ICANS were graded by ASTCT criteria (in phase 2). Here, Lee et al and CTCAE v5.0 were mapped to ASTCT for CRS and ICANS, respectively. Results: As of Sept 1, 2020, 97 pts with a median of 6 prior lines received cilta-cel. Overall response rate per independent review committee (primary endpoint) was 97% (95% CI, 91–99), with 67% achieving stringent complete response (sCR). Median time to first response was 1 month (range, 1–9), and median time to CR or better was 2 months (range, 1–15). Responses deepened over time, and median duration of response was not reached. Of 57 pts evaluable for minimal residual disease (MRD) assessment, 93% were MRD-negative at 10-5. The 12-month progression-free survival (PFS) and overall survival rates (95% CI) were 77% (66–84) and 89% (80–94), respectively; median PFS was not reached. Grade 3/4 hematologic AEs ≥20% included neutropenia (95%), anemia (68%), leukopenia (61%), thrombocytopenia (60%), and lymphopenia (50%). CRS occurred in 95% of pts (4% grade 3/4), with median time to onset of 7 d (range, 1–12), and median duration of 4 d (range, 1–14, excluding 1 pt with 97-d duration). CRS resolved in all but one with grade 5 CRS/haemophagocytic lymphohistiocytosis. CAR T-cell neurotoxicity occurred in 21% of pts (grade ≥3, 10%). Fourteen deaths occurred during the study after cilta-cel infusion: none within the first 30 days, 2 within 100 days; and 12 more than 100 days post infusion, of which 5 were due to disease progression, and 4 due to treatment-related AEs. Conclusions: A single infusion of cilta-cel yielded early, deep, and durable responses in heavily pretreated pts with MM, with a manageable safety profile at the RP2D. Cilta-cel is under further investigation in other MM populations in earlier lines of therapy and in outpatient settings. Clinical trial information: NCT03548207.

Background: The phase 1b/2 CARTITUDE-1 study (NCT03548207) is evaluating ciltacabtagene autoleucel (cilta-cel; JNJ-68284528; LCAR-B38M CAR-T cells), a chimeric antigen receptor T (CAR-T) cell therapy with 2 B-cell maturation antigen-targeting single-domain antibodies, in patients with relapsed/refractory (R/R) multiple myeloma (MM). Cytokine release syndrome (CRS), a known side effect of CAR-T therapy, can be mild to life-threatening and requires careful monitoring and management. Here, we analyzed CRS and cytokine profiles in CARTITUDE-1. Methods: Eligible patients (aged ≥18 years) had a diagnosis of MM per International Myeloma Working Group criteria, measurable disease, Eastern Cooperative Oncology Group performance status ≤1, received ≥3 prior regimens or were double-refractory to a proteasome inhibitor and immunomodulatory drug, and received an anti-CD38 antibody. Bridging therapy was permitted after apheresis. At 5-7 days prior to cilta-cel infusion, lymphodepletion was performed with cyclophosphamide 300 mg/m2 and fludarabine 30 mg/m2 daily for 3 days. Cilta-cel was administered as a single infusion at a target dose of 0.75×106 (range: 0.5-1.0×106) CAR+ viable T cells/kg. CRS was graded using Lee et al (Blood 2014) in the phase 1b portion and American Society for Transplantation and Cellular Therapy (ASTCT) in the phase 2 portion. In this combined analysis, Lee et al criteria were mapped to ASTCT criteria for patients in the phase 1b portion. Serum samples for cytokine profiling were collected prior to lymphodepletion, prior to cilta-cel infusion and 2 hours post-infusion on Day 1, at regular time points until Day 100, and if CRS was suspected or reported. Results: A total of 97 patients with R/R MM were treated with cilta-cel; median follow-up for this analysis was 8.8 months (range: 1.5-20.4). CRS was reported in 92 (94.8%) patients. A total of 48 (49.5%) patients had grade 1 CRS, 38 (39.2%) had grade 2, 4 (4.1%) had grade 3, and 1 had grade 5 (1.0%); maximum toxicity grade according to the ASTCT consensus grading system could not be derived for 1 patient with CRS in the phase 1b portion. Median time to CRS onset from cilta-cel infusion was 7.0 days (range: 1-12). Median duration of CRS was 4.0 days (range: 1-27, excluding n=1 with 97 days). Supportive measures to treat CRS or CRS symptoms were administered to 87 (89.7%) patients, most commonly tocilizumab (69.1%), acetaminophen (68.0%), corticosteroids (20.6%), and anakinra (18.6%). CRS resolved in 91 (98.9%) patients; the patient with grade 5 CRS/hemophagocytic lymphohistiocytosis died on Day 99 subsequent to sequelae of grade 4 CRS. Across all patients, levels of interleukin (IL)-6, IL-10, and interferon-γ peaked at Days 7-14 post-cilta-cel infusion. Conclusions: CRS after cilta-cel treatment was low grade and manageable in most patients with R/R MM. The low rate of grade ≥3 CRS, median time to CRS onset of 7.0 days, and median duration of 4.0 days suggests outpatient dosing of cilta-cel may be feasible; this approach is being explored in the phase 2 CARTITUDE-2 study (NCT04133636). Disclosures Lin: Gamida Cells: Consultancy; Sorrento: Consultancy, Membership on an entity's Board of Directors or advisory committees; Kite, a Gilead Company: Consultancy, Research Funding; Vineti: Consultancy; Takeda: Research Funding; Merck: Research Funding; Legend BioTech: Consultancy; Juno: Consultancy; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Janssen: Consultancy, Research Funding. Martin:Janssen: Research Funding; AMGEN: Research Funding; Sanofi: Research Funding; Seattle Genetics: Research Funding; GSK: Consultancy. Cohen:Novartis: Other: Patents/Intellectual property licensed, Research Funding; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Takeda,: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Membership on an entity's Board of Directors or advisory committees; Genentech/Roche: Membership on an entity's Board of Directors or advisory committees. 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. Usmani:Celgene: Other; Takeda: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; SkylineDX: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Pharmacyclics: Research Funding; GSK: Consultancy, Research Funding; Janssen: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Array Biopharma: Research Funding; Merck: Consultancy, Research Funding; Abbvie: Consultancy; BMS, Celgene: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Amgen: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Incyte: Research Funding. Madduri:AbbVie: Consultancy, Honoraria; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Speaking Engagement, Speakers Bureau; Foundation Medicine: Consultancy, Honoraria; Legend: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Speaking Engagement, Speakers Bureau; Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Kinevant: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Speaking Engagement, Speakers Bureau. Stewart:Janssen, BMS, Sanofi-Aventis, GSK: Honoraria; Tempus, Inc., Genomics England LLC: Membership on an entity's Board of Directors or advisory committees. Singh:Janssen: Current Employment. Zudaire:Janssen: Current Employment. Yeh:Janssen: Current Employment. Allred:Janssen: Current Employment. Olyslager:Janssen: Current Employment. Banerjee:Janssen: Current Employment. Goldberg:Johnson & Johnson: Current Employment, Current equity holder in publicly-traded company. Schecter:Janssen: Current Employment. Jackson:Memorial Sloan Kettering Cancer Center: Consultancy; Janssen: Current Employment. Deraedt:Janssen: Current Employment, Current equity holder in publicly-traded company. Geng:Legend Biotech USA Inc.: Current Employment. Wu:Legend Biotech USA Inc.: Current Employment. Carrasco:Legend Biotech USA Inc.: Current Employment. Akram:Legend Biotech USA Inc.: Current Employment. Hossain:Legend Biotech USA Inc.: Current Employment. Wang:Legend Biotech USA Inc.: Current Employment. Berdeja:CRISPR Therapeutics: Consultancy, Research Funding; EMD Sorono: Research Funding; Teva: Research Funding; Servier: Consultancy; Vivolux: Research Funding; Abbvie: Research Funding; Novartis: Research Funding; Janssen: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Karyopharm: Consultancy; Kesios: Research Funding; Kite Pharma: Consultancy; Legend: Consultancy; Genentech, Inc.: Research Funding; BMS: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Cellularity: Research Funding; Constellation: Research Funding; Glenmark: Research Funding; CURIS: Research Funding; Bioclinica: Consultancy; Amgen: Consultancy, Research Funding; Bluebird: Research Funding; Poseida: Research Funding; Acetylon: Research Funding; Prothena: Consultancy; Lilly: Research Funding. Jagannath:BMS, Janssen, Karyopharm, Legend Biotech, Sanofi, Takeda: Consultancy.

Background: Isatuximab (SAR650984) is an IgG1k monoclonal antibody that binds with high affinity to CD38 expressed on plasma cells in AL amyloidosis. It has been shown to be efficacious and well tolerated in relapsed and refractory multiple myeloma as a single agent and in combination. Here we report on the preliminary results of a prospective multi-center, phase II study of isatuximab in previously treated patients with AL amyloidosis (NCT03499808). Methods: Eligibility included age ≥ 18 years, relapsed or refractory systemic AL amyloidosis, ≥ 1 prior line of therapy, measurable disease (defined as a positive monoclonal serum immunofixation electrophoresis (IFE) or urine IFE, a serum free light chain ratio outside of the normal range (0.25-1.65), and a difference in the involved versus the uninvolved serum free light chain of ≥ 4.5 mg/dL), at least one organ involved, not refractory to daratumumab, ECOG performance status 0-2, creatinine clearance ≥25 mL/min as measured by 24-hour urine collection or as estimated by Cockcroft and Gault formula, and NT-proBNP ≤8500 pg/mL. Patients received isatuximab intravenously 20 mg/kg weekly during the first 28 day cycle and every other week during cycles 2 through 24 for a maximum of 24 cycles. The primary objective was hematologic response with secondary objectives of organ response, safety, progression free survival, and overall survival. Results: At data cut-off (July 24, 2020), 43 patients were registered from March 2018 to September 2019 at 14 institutions. Thirty six patients were eligible with 35 patients receiving at least one dose of isatuximab. Of the eligible patients, the median age was 70 (range 40-81). Prior therapies included proteasome inhibitors in 32 patients (89%), high dose therapy followed by autologous stem cell transplant in 17 patients (47%), immunomodulatory therapy in 9 patients (25%), and anti-CD38 monoclonal antibody therapy in 2 patients (6%). Single organ system involvement was seen in 19 patients (53%), ≥ 2 organ systems in 17 patients (47%), 16 patients (44%) had renal involvement, and 24 (67%) had cardiac involvement. For those with cardiac involvement, 7 patients (29%) had cardiac biomarker stage II and 9 patients (38%) had stage III disease using the Revised Mayo Staging (Kumar S et al., J Clin Oncol, 2012). A total of 17 patients remain on therapy. The median duration on treatment for eligible patients is currently 11.8 months (current range, 0.3-22.1). Of the 19 patients who discontinued treatment, the most common reasons included adverse events in 5 patients (26%), disease progression in 4 patients (21%), sub-optimal response in 2 patients (11%), and concerns related to COVID-19 in 2 patients (11%). The current median follow up is 16.3 months. The most common drug-related AEs were infusion related reactions in 18 patients (50%) with the majority (16/18) being grade I or II, anemia in 9 patients (25%) with the majority (8/9) being grade I, and lymphopenia in 8 patients (22%). Patient characteristics and preliminary safety data were previously presented at the International Symposium on Amyloidosis. The overall hematologic response rate was 77%. Hematological complete response (CR) was observed in 1 of 35 evaluable (completing at least 1 dose) patients (3%), very-good-partial response (VGPR) in 19 patients (54%), and partial response (PR) in 7 patients (20%). Conclusions: Isatuximab demonstrates encouraging efficacy in previously treated patients with AL amyloidosis. The administration of isatuximab in these patients is associated with a good safety profile similar to other monoclonal antibodies against CD38. The data will be updated at the meeting. Disclosures Sanchorawala: Prothena: Research Funding; Caelum: Research Funding; Oncopeptide: Research Funding; Janssen: Research Funding; Regeneron: Other: advisory board; Caleum: Other: advisory board; Proclara: Other: advisory board; Abbvie: Other: advisory board; UpToDate: Patents & Royalties; Takeda: Research Funding; Celgene: Research Funding. Kapoor:Sanofi: Consultancy, Research Funding; Celgene: Honoraria; Cellectar: Consultancy; Janssen: Research Funding; Amgen: Research Funding; GlaxoSmithKline: Research Funding; Takeda: Honoraria, Research Funding. Neparidze:GlaxoSmithKline: Research Funding; Janssen: Research Funding; Sanofi: Membership on an entity's Board of Directors or advisory committees, Other: Advisory board; Eidos Therapeutics: Membership on an entity's Board of Directors or advisory committees, Other: Diagnostic committee member . Sarosiek:Spectrum: Research Funding. Durie:Amgen, Celgene, Johnson & Johnson, and Takeda: Consultancy. Usmani:Incyte: Research Funding; Takeda: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; SkylineDX: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Array Biopharma: Research Funding; Pharmacyclics: Research Funding; Celgene: Other; Seattle Genetics: Consultancy, Research Funding; GSK: Consultancy, Research Funding; BMS, Celgene: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Amgen: Consultancy, Honoraria, Other: Speaking Fees, Research Funding; Abbvie: Consultancy. Orlowski:Laboratory research funding from BioTheryX, and clinical research funding from CARsgen Therapeutics, Celgene, Exelixis, Janssen Biotech, Sanofi-Aventis, Takeda Pharmaceuticals North America, Inc.: Research Funding; STATinMED Research: Consultancy; Founder of Asylia Therapeutics, Inc., with associated patents and an equity interest, though this technology does not bear on the current submission.: Current equity holder in private company, Patents & Royalties; Sanofi-Aventis, Servier, Takeda Pharmaceuticals North America, Inc.: Honoraria, Membership on an entity's Board of Directors or advisory committees; Amgen, Inc., AstraZeneca, BMS, Celgene, EcoR1 Capital LLC, Forma Therapeutics, Genzyme, GSK Biologicals, Ionis Pharmaceuticals, Inc., Janssen Biotech, Juno Therapeutics, Kite Pharma, Legend Biotech USA, Molecular Partners, Regeneron Pharmaceuticals, Inc.,: Honoraria, Membership on an entity's Board of Directors or advisory committees. OffLabel Disclosure: Isatuximab is FDA approved for relapsed refractory myeloma in combination with pomalidomide and dexamethasone. Isatuximab is not FDA approved for AL amyloidosis.

PURPOSE To evaluate the effects of daratumumab, lenalidomide, and dexamethasone (D-Rd) versus lenalidomide and dexamethasone (Rd) on patient-reported outcomes (PROs) in the phase III MAIA study. PATIENTS AND METHODS PROs were assessed on the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item and the EuroQol 5-dimensional descriptive system at baseline and every 3 months during treatment. By mixed-effects model, changes from baseline are presented as least squares means with 95% CIs. RESULTS A total of 737 transplant-ineligible (TIE) patients with newly diagnosed multiple myeloma were randomly assigned to D-Rd (n = 368) or Rd (n = 369). Compliance with PRO assessments was high at baseline (> 90%) through month 12 (> 78%) for both groups. European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item global health status scores improved from baseline in both groups and were consistently greater with D-Rd at all time points. A global health status benefit was achieved with D-Rd, regardless of age (< 75 and ≥ 75 years), baseline Eastern Cooperative Oncology Group (ECOG) performance status score, or depth of response. D-Rd treatment resulted in significantly greater reduction in pain scores as early as cycle 3 ( P = .0007 v Rd); the magnitude of change was sustained through cycle 12. Reductions in pain with D-Rd were clinically meaningful in patients regardless of age, ECOG status, or depth of response. Similarly, PRO improvements were observed with D-Rd and Rd on the EuroQol 5-dimensional descriptive system visual analog scale score. CONCLUSION D-Rd compared with Rd was associated with faster and sustained clinically meaningful improvements in PROs, including pain, in transplant-ineligible patients with newly diagnosed multiple myeloma regardless of age, baseline ECOG status, or depth of treatment response.