Pacaud, Lida

Abstract Background: Patients with relapsed and refractory multiple myeloma (RRMM) who have triple class exposure to immunomodulatory drugs (IMiDs), proteasome inhibitors (PIs) and anti-CD38 monoclonal antibodies (MoABs) have a poor prognosis and high unmet medical need. Ciltacabtagene autoleucel (cilta-cel) is a chimeric antigen receptor T-cell therapy which may offer long-term disease control for these patients. CARTITUDE-1 is an open-label, single arm phase 1b/2 clinical trial conducted to characterize the safety and efficacy of cilta-cel in adult patients with triple-class exposed RRMM. Since CARTITUDE-1 is a single-arm study, adjusted comparisons to other currently available therapies can provide valuable information on relative efficacy and safety benefits of cilta-cel over current real-world clinical practice (RWCP). LocoMMotion is the first prospective study of RWCP efficacy and safety outcomes in triple-class exposed patients with RRMM. It was designed a priori to serve as an external control cohort for CARTITUDE-1, using aligned inclusion criteria and endpoint definitions, to enable robust, high quality indirect comparisons vs. cilta-cel. Objective: To compare patient outcomes of cilta-cel vs. RWCP, including overall response rate (ORR), complete response or better rate (≥CR rate), progression-free survival (PFS) as assessed by a review committee and overall survival (OS) in patients with triple-class exposed RRMM. Methods: Individual patient level data available from both CARTITUDE-1 (clinical cut-off February 2021) and LocoMMotion (clinical cut-off March 2021) were pooled to conduct the comparative analyses. Imbalances between both cohorts on key prognostic baseline characteristics, including refractory status, ISS stage, time to progression on prior line, number of prior lines, average duration of prior lines, age, creatinine clearance, ECOG PS and MM type were adjusted for using inverse probability weighting. Average treatment effect on the treated (ATT) weights derived from propensity scores estimated using multivariable logistic regression modeling were applied to the LocoMMotion patients to have the weighted RWCP cohort reflecting the CARTITUDE-1 patient population. Balance between the ATT weighted RWCP cohort versus the CARTITUDE-1 population was evaluated based on reduction of standardized mean differences and overlap of propensity score distributions. Weighted logistic and Cox proportional hazards regression were used to estimate the relative treatment effects for cilta-cel vs. RWCP on binary endpoints (Odds ratios (OR), transformed into Response-rate Ratios (RR) and time to event endpoints (Hazard ratios (HR)), respectively. The base case analyses included all enrolled (apheresed) patients from CARTITUDE-1, reflecting an intention to treat approach. Additional analyses were conducted including only patients who received cilta-cel infusion compared to an aligned population of LocoMMotion where patients that progressed or died within 52 days were excluded from the LocoMMotion cohort. Results: 113 patients were enrolled in CARTITUDE-1, of which 97 were infused with cilta-cel. 246 patients were enrolled in LocoMMotion receiving RWCP in Italy (24%), Germany (15%), France (14%), UK (11%), Spain (10%), USA (9%), Belgium (5%), Poland (5%), Netherlands (4%) and Russia (3%). Therapies within the RWCP cohort were diverse and >90 unique treatment regimens were used. The most frequent regimens were Kd (13.8%), PCd (12.6%) and Pd (11.0%). The weighted LocoMMotion population was well balanced with the CARTITUDE-1 cohort. Adjusted comparisons (Table 1) showed statistically significant improvements for cilta-cel vs. RWCP for ORR (RR=4.43), ≥CR (RR=568.92), PFS (HR=0.15) and OS (HR=0.38), all comparisons with p<0.001. All additional analyses were consistent with these findings (Table 1). Conclusions: Outcomes for patients with triple-class exposed RRMM treated with RWPC observed in LocoMMotion are poor, illustrating the high unmet medical need. Adjusted comparisons vs. CARTITUDE-1 demonstrate significantly improved ORR, ≥CR, PFS and OS for cilta-cel compared to a diverse set of RWCP. These findings highlight cilta-cel's potential as a highly effective treatment option for patients with triple-class exposed RRMM. Figure 1 Figure 1. Disclosures Mateos: Regeneron: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Sea-Gen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Honoraria; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: 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; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bluebird bio: Honoraria; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees. Weisel: GSK: 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; Adaptive Biotechnologies: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; 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; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria; Oncopeptides: 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; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy; Novartis: Honoraria; Pfizer: Honoraria. Martin: Sanofi: Research Funding; Oncopeptides: Consultancy; Janssen: Research Funding; GlaxoSmithKline: Consultancy; Amgen: Research Funding. Berdeja: Celularity, CRISPR Therapeutics: Research Funding; Abbvie, Acetylon, Amgen: Research Funding; Bluebird bio, BMS, Celgene, CRISPR Therapeutics, Janssen, Kite Pharma, Legend Biotech, SecuraBio, Takeda: Consultancy; EMD Sorono, Genentech: Research Funding; GSK, Ichnos Sciences, Incyte: Research Funding; Lilly, Novartis: Research Funding; Poseida, Sanofi, Teva: Research Funding. Jakubowiak: Karyopharm: Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees; Abbvie: 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. Stewart: Oncopeptides: Honoraria; Janssen: Honoraria; GSK: Honoraria; BMS: Honoraria; Amgen: Honoraria; Skyline diagnostics: Consultancy; Genomcs England: Membership on an entity's Board of Directors or advisory committees; Tempus Inc.: Current holder of individual stocks in a privately-held company, Membership on an entity's Board of Directors or advisory committees; PikSci Inc.: Current holder of individual stocks in a privately-held company, Patents & Royalties; Sanofi Aventis: Honoraria. Jagannath: Legend Biotech: Consultancy; Bristol Myers Squibb: Consultancy; Karyopharm Therapeutics: Consultancy; Janssen Pharmaceuticals: Consultancy; Takeda: Consultancy; Sanofi: Consultancy. Lin: Novartis: Consultancy; Bluebird Bio: Consultancy, Research Funding; Legend: Consultancy; Sorrento: Consultancy; Juno: Consultancy; Takeda: Research Funding; Celgene: Consultancy, Research Funding; Gamida Cell: Consultancy; Vineti: Consultancy; Merck: Research Funding; Janssen: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, Research Funding. Diels: Janssen: Current Employment. Ghilotti: Janssen-Cilag SpA, Cologno Monzese, Italy: Current Employment. Perualila: Janssen: Current Employment. Cabrieto: Janssen: Current Employment. Haefliger: Janssen-Cilag AG: Ended employment in the past 24 months; Cilag GmbH International: Current Employment. Erler-Yates: Janssen: Current Employment. Hague: Janssen: Current Employment, Current equity holder in publicly-traded company. Jackson: Janssen: Current Employment; Memorial Sloan Kettering Cancer Center: Consultancy. Strulev: Janssen Pharmaceutica NV: Current Employment. Nesheiwat: Legend Biotech USA: Current Employment. Pacaud: Legend Biotech: Current Employment. Moreau: Janssen: Honoraria; Celgene BMS: Honoraria; Amgen: Honoraria; Sanofi: Honoraria; Abbvie: Honoraria; Oncopeptides: Honoraria. Einsele: Janssen, Celgene/BMS, Amgen, GSK, Sanofi: Consultancy, Honoraria, Research Funding.

Abstract Introduction: Ciltacabtagene autoleucel (cilta-cel), a chimeric antigen receptor T (CAR-T) cell therapy with 2 B-cell maturation antigen (BCMA) targeting single-domain antibodies, demonstrated early, deep, and durable responses in the phase 1b/2 CARTITUDE-1 study in patients (pts) with relapsed/refractory multiple myeloma (RRMM) who had been heavily pretreated (Berdeja, Lancet, 2021). After a median follow-up of 12.4 months, the overall response rate (ORR; as assessed by independent review committee) was 97%, with 67% of pts achieving stringent complete response (sCR). The 12-month progression-free survival (PFS) and overall survival (OS) rates were 77% and 89%, respectively. Here, we report updated results from CARTITUDE-1 with longer duration of follow-up (median 18 months). Methods: Eligible pts had MM and received ≥3 prior therapies or were refractory to a proteasome inhibitor (PI) and an immunomodulatory drug (IMiD), and had received a PI, IMiD, and an 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 (d) after lymphodepletion (300 mg/m 2 cyclophosphamide, 30 mg/m 2 fludarabine daily for 3 d). Primary objectives were to characterize cilta-cel safety, confirm the recommended phase 2 dose (phase 1b), and evaluate cilta-cel efficacy (phase 2). Response was assessed per IMWG criteria by an independent review committee and minimal residual disease (MRD) negativity at 10 -5 by next-generation sequencing. In this combined phase 1b and phase 2 analysis, cytokine release syndrome (CRS; per Lee et al Blood 2014 grading criteria) and neurotoxicity (by CTCAE v5.0) were mapped to the ASTCT criteria for CRS and immune effector cell-associated neurotoxicity (ICANS), respectively. Results: As of Feb 11, 2021, 97 pts (58.8% male; median age 61.0 years [range 43-78]) received cilta-cel. Pts had received a median of 6 (range 3-18) prior lines of therapy; 83.5% were penta-drug exposed, 87.6% were triple-class refractory, 42.3% were penta-drug refractory, and 99.0% were refractory to last line of therapy. ORR was 97.9% (95% CI: 92.7-99.7); 80.4% of pts achieved sCR, and 94.8% achieved very good partial response or better (Figure). The median time to first response was 1 month (range 0.9-10.7), median time to best response was 2.6 months (range 0.9-15.2), and median time to complete response or better was 2.6 months (range 0.9-15.2). The median duration of response was 21.8 months (95% CI: 21.8-not estimable). Of 61 pts evaluable for MRD, 91.8% were MRD negative at the 10 -5 threshold; MRD 10 -5 negativity was sustained for ≥6 months in 44.3% (27/61) of pts and ≥12 months in 18% (11/61) of pts. The 18-month PFS and OS rates were 66.0% (95% CI: 54.9-75.0) and 80.9% (95% CI: 71.4-87.6), respectively. 18-month PFS rates in pts who achieved sustained MRD for ≥6 months and ≥12 months were 96.3% (95% CI: 76.5-99.5) and 100%, respectively. The most common grade 3/4 hematologic AEs in ≥25% of pts were neutropenia (94.8%), anemia (68.0%), leukopenia (60.8%), thrombocytopenia (59.8%), and lymphopenia (49.5%). There were no fatalities related to cytopenias, and no new safety signals with longer follow-up. CRS occurred in 94.8% of pts (mostly grade 1/2); median time to onset was 7 d (range 1-12), and CRS resolved within 14 d in 98.9% of pts. There was no new CAR T-cell neurotoxicity since the previous report. Post cilta-cel infusion, 21 deaths occurred during the study: 0 within first 30 d, 2 within 100 d, and 19 more than 100 d post infusion. Ten deaths were due to disease progression, 6 were treatment-related (as assessed by the investigator), and 5 were due to AEs unrelated to treatment. One patient was retreated with cilta-cel (for progressive disease) and had stable disease (per computerized algorithm) post-retreatment with no incidence of CAR T-cell neurotoxicity. Conclusions: At a longer median follow-up of 18 months, a single cilta-cel infusion led to early, deep, and durable responses in heavily pre-treated pts with MM. Follow-up is ongoing and updated data will be presented. Cilta-cel demonstrated a manageable safety profile with no new safety signals observed with longer follow-up. Further investigations of cilta-cel are ongoing in earlier lines of therapy (CARTITUDE-2 [NCT04133636], CARTITUDE-4 [NCT04181827], and CARTITUDE-5 [NCT04923893]) and in outpatient settings. Figure 1 Figure 1. Disclosures Martin: GlaxoSmithKline: Consultancy; Janssen: Research Funding; Sanofi: Research Funding; Amgen: Research Funding. Usmani: Takeda: Consultancy, Research Funding, Speakers Bureau; SkylineDX: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Pharmacyclics: Consultancy, Research Funding; Merck: Consultancy, Research Funding; Janssen Oncology: Consultancy, Research Funding; Bristol-Myers Squibb: Research Funding; EdoPharma: Consultancy; Array BioPharma: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; GSK: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding, Speakers Bureau; Janssen: Consultancy, Research Funding, Speakers Bureau; Amgen: Consultancy, Research Funding, Speakers Bureau; Abbvie: Consultancy. Berdeja: Lilly, Novartis: Research Funding; Poseida, Sanofi, Teva: Research Funding; GSK, Ichnos Sciences, Incyte: Research Funding; Bluebird bio, BMS, Celgene, CRISPR Therapeutics, Janssen, Kite Pharma, Legend Biotech, SecuraBio, Takeda: Consultancy; Celularity, CRISPR Therapeutics: Research Funding; Abbvie, Acetylon, Amgen: Research Funding; EMD Sorono, Genentech: Research Funding. Jakubowiak: Amgen: Membership on an entity's Board of Directors or advisory committees; GSK: Membership on an entity's Board of Directors or advisory committees; Janssen: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Abbvie: 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; Sanofi: Membership on an entity's Board of Directors or advisory committees; Celgene: Membership on an entity's Board of Directors or advisory committees. Cohen: Novartis: Research Funding; BMS/Celgene: Consultancy; Takeda: Consultancy; Genentech/Roche: Consultancy; Oncopeptides: Consultancy; AstraZeneca: Consultancy; Janssen: Consultancy; GlaxoSmithKline: Consultancy, Research Funding. Hari: Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Karyopharm: Consultancy; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, 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; 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; 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; Celgene-BMS: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau. Avigan: Celgene: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pharmacyclics: Research Funding; Kite Pharma: Consultancy, Research Funding; Juno: Membership on an entity's Board of Directors or advisory committees; Partner Tx: Membership on an entity's Board of Directors or advisory committees; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Membership on an entity's Board of Directors or advisory committees; Aviv MedTech Ltd: Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Legend Biotech: Membership on an entity's Board of Directors or advisory committees; Chugai: Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy; Parexcel: Consultancy; Takeda: Consultancy; Sanofi: Consultancy. Deol: Kite, a Gilead Company: Consultancy. Lesokhin: bristol myers squibb: Research Funding; Iteos: Consultancy; pfizer: Consultancy, Research Funding; Behringer Ingelheim: Honoraria; Trillium Therapeutics: Consultancy; Serametrix, Inc: Patents & Royalties; Genetech: Research Funding; Janssen: Honoraria, Research Funding. Munshi: Adaptive Biotechnology: Consultancy; Karyopharm: Consultancy; Oncopep: Consultancy, Current equity holder in publicly-traded company, Other: scientific founder, Patents & Royalties; Legend: Consultancy; Novartis: Consultancy; Abbvie: Consultancy; Celgene: Consultancy; Janssen: Consultancy; Takeda: Consultancy; Amgen: Consultancy; Pfizer: Consultancy; Bristol-Myers Squibb: Consultancy. O'Donnell: Onocopeptide: Consultancy; Karyopharm: Consultancy; Janssen: Consultancy; Bristol Myer Squibb: Consultancy; Adaptive: Consultancy; Takeda: Consultancy. Stewart: Oncopeptides: Honoraria; Janssen: Honoraria; GSK: Honoraria; BMS: Honoraria; Amgen: Honoraria; Skyline diagnostics: Consultancy; Genomcs England: Membership on an entity's Board of Directors or advisory committees; Tempus Inc.: Current holder of individual stocks in a privately-held company, Membership on an entity's Board of Directors or advisory committees; PikSci Inc.: Current holder of individual stocks in a privately-held company, Patents & Royalties; Sanofi Aventis: Honoraria. Schecter: Janssen: Current Employment, Current holder of stock options in a privately-held company. Goldberg: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. Jackson: Janssen: Current Employment; Memorial Sloan Kettering Cancer Center: Consultancy. Yeh: Janssen: Current Employment. Banerjee: Janssen: Current Employment, Current holder of individual stocks in a privately-held company. 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. Olyslager: Janssen: Current Employment. Pacaud: Legend Biotech: Current Employment. Lin: Juno: Consultancy; Bluebird Bio: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Novartis: Consultancy; Takeda: Research Funding; Kite, a Gilead Company: Consultancy, Research Funding; Vineti: Consultancy; Gamida Cell: Consultancy; Sorrento: Consultancy; Legend: Consultancy; Merck: Research Funding; Janssen: Consultancy, Research Funding. Jagannath: Legend Biotech: Consultancy; Karyopharm Therapeutics: Consultancy; Janssen Pharmaceuticals: Consultancy; Bristol Myers Squibb: Consultancy; Sanofi: Consultancy; Takeda: 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 Background: Ciltacabtagene autoleucel (cilta-cel) is a novel chimeric antigen receptor T-cell therapy that is being evaluated in the CARTITUDE-1 trial (NCT03548207) in patients with relapsed or refractory multiple myeloma (RRMM) who are triple-class exposed (to immunomodulatory drugs, proteasome inhibitors, and an anti-CD38 monoclonal antibody). As there is no clear standard of care for this patient population, and due to an absence of direct head-to-head trials evaluating cilta-cel and other relevant treatments, indirect treatment comparisons (ITCs) between cilta-cel and treatments used in current clinical practice, ie, physician's choice of treatment (PCT), have been previously conducted. Meta-analyses were performed to derive single summary effect estimates for overall survival (OS) and progression-free survival (PFS) by pooling ITCs evaluating cilta-cel versus PCT in patients with triple-class exposed RRMM. Methods: ITCs examining the comparative effectiveness of cilta-cel versus PCT on OS and PFS were included. Data on cilta-cel corresponded to the February 2021 data-cut for CARTITUDE-1. Data on PCT was leveraged from the following sources: (i) the Flatiron database, a primarily US community-based multiple myeloma registry, (ii) the long-term follow-up results of three global RRMM daratumumab randomized clinical trials (POLLUX [NCT02076009], CASTOR [NCT02136134], and EQUULEUS [NCT01998971]), (iii) the US-based retrospective MAMMOTH study, and (iv) a representative German patient registry maintained by OncologyInformationService (OIs). In each ITC, the PCT group was comprised of patients who satisfied key eligibility criteria for CARTITUDE-1 and was made comparable to CARTITUDE-1 using inverse probability of treatment weighting. Hence, the ITCs were deemed appropriate to meta-analyze. The meta-analyses used a robust variance estimator to account for the use of CARTITUDE-1 in each pairwise ITC. The main meta-analyses considered all participants treated with cilta-cel in CARTITUDE-1 compared with PCT. Sensitivity analyses considered ITC effect estimates based on all enrolled participants in CARTITUDE-1. Pooled summary effect estimates were presented as hazard ratios (HRs) with the corresponding 95% confidence intervals (CIs). Results: Based on availability of data, the main meta-analyses included four ITCs for OS and three ITCs for PFS. Cilta-cel was associated with a statistically significant improvement in OS (HR: 0.21, 95% CI: 0.13 to 0.34; Figure 1) and PFS (HR: 0.20, 95% CI: 0.07 to 0.63; Figure 2) compared to PCT. Sensitivity analyses including all enrolled participants confirmed the results of the main meta-analyses. Conclusions: In the meta-analyses, cilta-cel demonstrated a significant advantage over PCT in terms of OS and PFS, highlighting its potential as an effective therapy in patients with triple-class exposed RRMM. Figure 1 Figure 1. Disclosures Hari: GSK: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Janssen: 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; Amgen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Other, Research Funding, Speakers Bureau; Karyopharm: Consultancy; Sanofi: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Consultancy, Honoraria, 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; Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding. Berdeja: EMD Sorono, Genentech: Research Funding; Celularity, CRISPR Therapeutics: Research Funding; Bluebird bio, BMS, Celgene, CRISPR Therapeutics, Janssen, Kite Pharma, Legend Biotech, SecuraBio, Takeda: Consultancy; Abbvie, Acetylon, Amgen: Research Funding; GSK, Ichnos Sciences, Incyte: Research Funding; Lilly, Novartis: Research Funding; Poseida, Sanofi, Teva: Research Funding. Gay: Bluebird Bio: Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Membership on an entity's Board of Directors or advisory committees; Roche: Membership on an entity's Board of Directors or advisory committees; GlaxoSmithKline: Honoraria, Membership on an entity's Board of Directors or advisory committees; AbbVie: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bristol-Myers Squibb: Honoraria; Takeda: 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; Celgene: 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; Sanofi: Consultancy, Honoraria. Hooper: Eversana: Current Employment; Janssen: Consultancy. Haltner: Eversana: Current Employment; Janssen: Consultancy. Kumar: Carsgen: Research Funding; Novartis: Research Funding; Merck: Research Funding; Bluebird Bio: Consultancy; Roche-Genentech: Consultancy, Research Funding; Oncopeptides: Consultancy; Astra-Zeneca: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Antengene: Consultancy, Honoraria; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Beigene: Consultancy; KITE: 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; 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; Amgen: Consultancy, Research Funding; Abbvie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; BMS: Consultancy, Research Funding; Sanofi: Research Funding. Martin: Sanofi: Research Funding; Janssen: Research Funding; GlaxoSmithKline: Consultancy; Amgen: Research Funding; Oncopeptides: Consultancy. Mateos: AbbVie: Honoraria; Oncopeptides: Honoraria, Membership on an entity's Board of Directors or advisory committees; Regeneron: 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; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees; Celgene - Bristol Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bluebird bio: Honoraria; Pfizer: Honoraria, Membership on an entity's Board of Directors or advisory committees; Oncopeptides: Honoraria; Adaptive Biotechnologies: Honoraria, Membership on an entity's Board of Directors or advisory committees; Sea-Gen: Honoraria, Membership on an entity's Board of Directors or advisory committees; GSK: Honoraria; Sanofi: 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. Moreau: Sanofi: Honoraria; Janssen: Honoraria; Celgene BMS: Honoraria; Oncopeptides: Honoraria; Amgen: Honoraria; Abbvie: Honoraria. Rosta: EVERSANA: Current Employment; Janssen Inc.: Consultancy. Samjoo: EVERSANA: Current Employment; Janssen Inc.: Consultancy. Usmani: GSK: Consultancy, Research Funding; Abbvie: Consultancy; Array BioPharma: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding, Speakers Bureau; EdoPharma: Consultancy; Seattle Genetics: Consultancy, Research Funding; Janssen Oncology: Consultancy, Research Funding; SkylineDX: Consultancy, Research Funding; Takeda: Consultancy, Research Funding, Speakers Bureau; Janssen: Consultancy, Research Funding, Speakers Bureau; Merck: Consultancy, Research Funding; Sanofi: Consultancy, Research Funding, Speakers Bureau; Pharmacyclics: Consultancy, Research Funding; Bristol-Myers Squibb: Research Funding; Amgen: Consultancy, Research Funding, Speakers Bureau. Weisel: Celgene: 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; GSK: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Karyopharm: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; 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; Roche: Honoraria; Oncopeptides: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Sanofi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Consultancy; Novartis: Honoraria; Pfizer: Honoraria. Jackson: Janssen: Current Employment; Memorial Sloan Kettering Cancer Center: Consultancy. Olyslager: Janssen: Current Employment. Schecter: Janssen: Current Employment, Current holder of stock options in a privately-held company. Vogel: Janssen Global Services, LLC: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company, Divested equity in a private or publicly-traded company in the past 24 months. Garrett: Legend Biotech USA: Current Employment. Lee: Legend Biotech: Current Employment, Current equity holder in publicly-traded company. Nesheiwat: Legend Biotech USA: Current Employment. Pacaud: Legend Biotech: Current Employment. Valluri: Janssen: Current Employment, Current equity holder in publicly-traded company. Costa: Amgen: Consultancy, Honoraria, Research Funding, Speakers Bureau; Sanofi: Consultancy, Honoraria, Speakers Bureau; BMS: Consultancy, Honoraria, Research Funding; Karyopharm: Consultancy, Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Pfizer: Consultancy, Honoraria. Lin: Merck: Research Funding; Bluebird Bio: Consultancy, Research Funding; Juno: Consultancy; Takeda: Research Funding; Legend: Consultancy; Sorrento: Consultancy; Gamida Cell: Consultancy; Vineti: Consultancy; Novartis: Consultancy; Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding; Kite, a Gilead Company: Consultancy, 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.