Facon, Thierry T.F.

AbstractThe phase 3 FIRST trial demonstrated significant improvement in progression‐free survival (PFS) and overall survival (OS) with an immune‐stimulatory agent, lenalidomide, in combination with low‐dose dexamethasone until disease progression (Rd continuous) vs melphalan +prednisone + thalidomide (MPT) in transplant‐ineligible patients with newly diagnosed multiple myeloma (NDMM). Rd continuous similarly extended PFS vs fixed‐duration Rd for 18 cycles (Rd18). Outcomes in the Canadian/US subgroup (104 patients per arm) are reported in this analysis. Rd continuous demonstrated a significant improvement in PFS vs MPT (median, 29.3 vs 20.2 months; HR, 0.69 [95% CI, 0.49‐0.97]; p = 0.03326) and an improvement vs Rd18 (median, 21.9 months). Median OS was 56.9 vs 46.8 months with Rd continuous vs MPT (p = 0.15346) and 59.5 months with Rd18. The overall response rate was higher with Rd continuous and Rd18 (78.8% and 79.8%) vs MPT (65.4%). In the 49.0%, 52.9%, and 29.8% of patients with at least very good partial response in the Rd continuous, Rd18, and MPT arms, respectively, the median PFS was 56.0, 30.9, and 40.2 months, respectively. The most common grade 3/4 treatment‐emergent adverse events were neutropenia (28.4%, 30.1%, and 52.0%), anemia (23.5%, 21.4%, and 23.5%), and infections (37.3%, 30.1%, and 24.5%) with Rd continuous, Rd18, and MPT, respectively. These results were consistent with those in the intent‐to‐treat population, confirming the benefit of Rd continuous vs MPT in the Canadian/US subgroup and supporting the role of Rd continuous as a standard of care for transplant‐ineligible patients with NDMM.

Abstract Daratumumab in combination with lenalidomide‐dexamethasone (D‐Rd) recently received FDA approval for the treatment of transplant‐ineligible patients with newly diagnosed multiple myeloma (NDMM). The present PEGASUS study compared progression‐free survival (PFS) in patients treated with D‐Rd in the MAIA trial and patients treated with common standard‐of‐care regimens from the Flatiron Health electronic health record‐derived deidentified database, which has data from patients treated primarily at community‐based oncology practices in the United States. Individual‐level patient data from both data sources were used to perform an anchored indirect treatment comparison (ITC) of D‐Rd to bortezomib‐lenalidomide‐dexamethasone (VRd) and bortezomib‐dexamethasone (Vd); lenalidomide‐dexamethasone (Rd) was the common anchor for the ITC. Hazard ratios (HRs) reflecting direct comparisons of PFS within MAIA (D‐Rd vs Rd) and Flatiron Health (VRd vs Rd; Vd vs Rd) were used to make ITCs for D‐Rd vs VRd and Vd, respectively. After application of MAIA inclusion/exclusion criteria and propensity‐score weighting, the Flatiron Health patients resembled the MAIA trial population on measured baseline characteristics. Based on the direct comparison within MAIA, treatment with D‐Rd was associated with a significantly lower risk of progression or death compared to Rd (HR 0.54; 95% CI 0.42, 0.71). Based on the ITCs, D‐Rd was associated with a significantly lower risk of progression or death compared to VRd (HR 0.68; 95% CI 0.48, 0.98) and Vd (HR 0.48; 95% CI 0.33, 0.69). In the absence of head‐to‐head trials comparing D‐Rd to VRd or Vd, the present ITC may help inform treatment selection in transplant‐ineligible patients with NDMM.

e19505 Background: CFZ combined with dexamethasone is approved to treat pts with RRMM, with CFZ given once-weekly at 70 mg/m2 (Kd70 QW) or twice-weekly at 56 mg/m2 (Kd56 BIW). No randomized trials have directly compared Kd70 QW with Kd56 BIW. We performed a post hoc comparison between pts who received Kd56 BIW in the ENDEAVOR trial and pts who received Kd70 QW in the A.R.R.O.W. or CHAMPION-1 trials. Methods: Data were analyzed from 3 trials of CFZ in RRMM: A.R.R.O.W. (240 pts in Kd70 QW arm; 2–3 prior therapies and refractory to most recent therapy), CHAMPION-1 (104 pts received Kd70 QW; 1–3 prior therapies), and ENDEAVOR (464 pts in Kd56 BIW arm; 1–3 prior therapies). Pts who received Kd70 QW in A.R.R.O.W. and CHAMPION-1 were pooled and compared with pts who received Kd56 BIW in ENDEAVOR. As study populations slightly varied among the 3 trials, an analysis of safety and efficacy was performed in a subgroup of pts who received 2–3 prior therapy lines and were not refractory to bortezomib (BTZ). Also, we performed regression analyses (controlling for age, ISS stage, BTZ and lenalidomide refractory status, and number of prior regimens) among all pts in the trials who received Kd70 QW or Kd56 BIW. Results: Among BTZ non-refractory pts with 2–3 lines of prior therapy, median progression-free survival (PFS) was 12.1 months (95% CI 8.4–14.3) for Kd70 QW (n = 146) and 14.5 months (95% CI 10.2–NE) for Kd56 BIW (n = 217), and the overall response rate (ORR) was 69.9% (95% CI 61.7–77.2) for Kd70 QW and 72.4% (95% CI 65.9–78.2) for Kd56 BIW. The rate of grade ≥3 adverse events (Kd70 QW vs Kd56 BIW) was 67.6% and 85.3%; among adverse events of interest, the grade ≥3 rate was 1.4% and 5.1% for cardiac failure, 3.4% and 6.0% for renal failure, and 5.5% and 15.7% for hypertension. Kd70 QW represents a convenient and well-tolerated treatment modality for pts with RRMM. In a Cox proportional hazards model, the hazard ratio for PFS (Kd70 QW vs Kd56 BIW) was 0.91 (95% CI 0.69–1.19), and in a logistic regression model the odds ratio for ORR (Kd70 QW vs Kd56 BIW) was 1.12 (95% CI 0.74–1.69). Conclusions: This post hoc analysis suggests that once-weekly Kd70 has a comparable benefit-risk profile to twice-weekly Kd56. Clinical trial information: NCT02412878, NCT01677858, NCT01568866.

8035 Background: D-Rd significantly reduced the risk of progression/death by 44% in transplant-ineligible NDMM pts vs Rd in the phase 3 MAIA study. To examine the impact of age on efficacy/safety of D-Rd vs Rd in this population, a subgroup analysis was conducted in pts <75 and ≥75 y of age. Methods: Transplant-ineligible NDMM pts were randomized 1:1 to Rd ± DARA; stratification was based on age (<75 vs ≥75 y), ISS (I, II, III), and region (North America vs Other). Pts received 28-day cycles of either R 25 or 10 mg (based on renal function) PO QD on Days 1-21 and either d 40 or 20 mg (based on age or BMI) PO/IV weekly until progression. In the D-Rd arm, pts received daratumumab 16 mg/kg IV QW for Cycles 1-2, Q2W for Cycles 3-6, and Q4W thereafter until progression. PFS is the primary endpoint. Results: Among 737 randomized pts (D-Rd, n=368; Rd, n=369), 321 (44%) were ≥75 y of age. For D-Rd vs Rd, relative median dose intensity for R was 79% vs 93% for <75 y subgroup and 66% vs 89% for ≥75 y subgroup, respectively. After median follow-up of 28 mo, significant PFS benefit of D-Rd vs Rd was maintained in both <75 and ≥75 y subgroups (Table). Deeper responses and MRD-negative rate (10-5 threshold) remained higher with D-Rd vs Rd in both subgroups (Table). Most common (≥10%; D-Rd/Rd) grade 3/4 TEAEs in ≥75 y pts were neutropenia (60%/41%), lymphopenia (19%/12%), anemia (16%/22%), pneumonia (15%/10%), leukopenia (12%/6%), and thrombocytopenia (8%/11%). Fewer pts receiving D-Rd vs Rd discontinued treatment due to TEAEs (<75 y: 5% vs 12%; ≥75 y: 10% vs 21%). Conclusions: D-Rd pts received less R vs Rd group regardless of age. Efficacy of D-Rd in <75 and ≥75 y pts was consistent with the ITT population, and D-Rd demonstrated acceptable tolerability regardless of age. Together with the phase 3 ALCYONE study, these studies confirm clinical benefit of daratumumab plus standard-of-care in transplant-ineligible NDMM pts ≥75 y of age. Clinical trial information: NCT02252172. [Table: see text]

8016 Background: MAIA, an ongoing phase 3 trial of transplant-ineligible patients (pts) with NDMM, demonstrated significant improvement in progression-free survival with D-Rd vs Rd alone. Assessment of pt-reported outcomes alongside efficacy endpoints provides pt perspective on their quality of survival and overall value of HRQoL while on treatments (tx). Methods: The EORTC QLQ-C30 and EQ-5D-5L questionnaires were completed by pts using an electronic device at baseline and every 3 mo during tx; interim results are presented for first 12 mo. Tx effects were assessed using repeated measures, mixed effects models and thresholds for clinically meaningful benefit were based on established criterion from the literature. Results: Compliance rates were high and comparable at baseline ( > 90%) and through month 12 ( > 80%) for both groups (D-Rd [n = 368]; Rd [n = 369]). Improvement in Global Health Status (GHS) occurred in both groups; however, for D-Rd, significantly greater improvement was observed at cycle 3 (LS mean change; D-Rd: 4.5 [95% CI: 2.4, 6.6], Rd: 1.5 [95% CI: -0.7, 3.7]; [p = 0.0454]) and increasing improvement occurred across all time points. Significant improvement and clinically meaningful benefit in HRQoL for D-Rd was also observed in EQ-5D-5L Visual Analog Scale (VAS) scores (LS mean change; D-Rd: 10.1 [95% CI: 8.1, 12.1], Rd: 4.9 [95% CI: 2.8, 7.0]; [p = 0.0002]). The VAS median time to worsening was 10 mo longer for D-Rd. Of note, meaningful differences were observed between the tx groups in two subscale scores, pain symptoms and cognitive functioning. Statistically significant less pain was reported early with D-Rd (LS mean change at cycle 3; D-Rd: -17.9 [95% CI: -20.7, -15.0], Rd: -11.0 [95% CI: -14.0, -8.1]; [p = 0.0007]); clinically meaningful reduction in pain symptoms was sustained with D-Rd. There was a decline in cognitive functioning at cycle 12 in both tx arms, with no statistically significant differences between groups. Conclusions: Faster and sustained improvement in HRQoL was observed in pts treated with D-Rd vs Rd with similar findings reflected across pain subscale. Clinical trial information: NCT02252172.

8589 Background: Denosumab (dmab) is a fully human monoclonal antibody against RANKL and is superior to ZA in preventing skeletal-related events (SREs) as shown in 3 identically designed phase 3 trials (N=5723). Overall survival (OS) was balanced between treatment groups in the overall study populations of these trials. In the trial of patients (pts) with solid tumors (excluding breast and prostate) and multiple myeloma (MM), OS was longer for dmab pts with lung cancer, shorter for pts with MM, and balanced for pts with other solid tumors. This analysis further characterizes the results from the MM subset of this trial. Methods: Pts with solid tumors or MM were randomized (1:1) to receive 120 mg of SC dmab or 4 mg of IV ZA Q4W. Daily calcium and vit D supplements were strongly recommended. The primary endpoint was the time to first on-study SRE; results from the primary endpoint and lung cancer subset were previously reported. Results: Of 1776 randomized pts, 10% had MM (93 ZA, 87 dmab). OS favored ZA (hazard ratio: 2.26; 10 subject difference in deaths). 1-year OS was 83% dmab, 97% ZA. Imbalances in baseline prognostic characteristics were observed. More pts in the dmab arm had low baseline renal function (CrCl < 40 mL/min) (ZA 2 [2%], dmab 9 [10%]) and more ZA pts underwent stem cell transplant (ZA 23 [25%], dmab 15 [17%]). Additionally, more ZA pts had stage I tumors at diagnosis (ZA 13 [14%], dmab 9 [10%]) and better performance status (ECOG = 0; ZA 30 [32%], dmab 21 [24%]). Study discontinuations due to consent withdrawal or lost to follow-up were also higher in the ZA group (ZA 17 [18%], dmab 11 [13%]) and occurred earlier in the ZA arm (ZA 59%, dmab 45% within 9 months of randomization). Conclusions: In this SRE study of dmab vs ZA, pts were stratified by baseline characteristics known to affect SRE outcomes, but not by prognostic factors or concurrent anticancer therapy that may impact survival in MM. OS results in the MM cohort are difficult to interpret due to small sample size and imbalances in baseline disease characteristics, stem cell transplant therapy, and consent withdrawal or loss of follow-up that favored ZA. A phase 3 trial is currently underway, which controls for these factors in pts with MM. Clinical trial information: NCT00330759.

7522 Background: Lenalidomide (len), an analog of thalidomide (thal) is a novel, oral immunomodulatory agent that is effective against multiple myeloma (MM). Two randomized, Phase III trials (MM009 and MM010) have recently demonstrated superior responses and overall survival (OS) for patients (pts) treated with len and dexamethasone (dex) in comparison with dex-placebo. This is a prospective subgroup analysis to assess the impact of prior therapy with thal on the sensitivity of MM to subsequent lenalidomide. Methods: We evaluated 692 pts from both trials (MM009 and MM010). The pts had relapsed/refractory MM, were not refractory to dex and were randomized to receive either len (25 mg daily for 3 weeks (wks) every 4 wks) plus dex (40 mg on days 1–4, 9–12, 17–20 every 4 wks for 4 cycles, then 40 mg on days 1–4 every subsequent cycle) or placebo plus dex. Standard criteria were used to evaluate response and TTP. Results: Pooled data from 692 pts showed superior median TTP (48.1 vs 20.1 wks) and OR (59.2% vs 22.5%) in pts treated with len/dex compared to dex-placebo (p <0.001). Although subgroup analysis of pts with prior thal therapy revealed that pts who received len/dex had significantly improved OR, PR CR and median TTP than pts who received dex-placebo, OR, CR and TTP were highest in len/dex pts not previously treated with thal. Multivariate analysis indicates that after controlling for the treatment factor and baseline disease characteristics, whether or not pt had prior exposure to thal is a marginally significant variable to predict TTP. The risk of deep venous thrombosis and pulmonary embolism in these subgroups will be updated on further analysis. Conclusions: Lenalidomide in combination with dexamethasone is more effective than dexamethasone-placebo regardless of prior thalidomide in relapsed/refractory multiple myeloma. [Table: see text] [Table: see text]

Abstract Combination of carfilzomib with dexamethasone (Kd) is approved for use in relapsed and/or refractory multiple myeloma (RRMM), with carfilzomib administered twice weekly at 56 mg/m 2 (Kd56 BIW) or once weekly at 70 mg/m 2 (Kd70 QW). Post hoc cross‐trial comparisons were performed to compare efficacy and safety profiles of Kd70 QW vs Kd56 BIW dosing schedules using data from three trials of patients with RRMM: A.R.R.O.W., CHAMPION‐1, and ENDEAVOR. To select for comparable patient populations, side‐by‐side efficacy and safety comparisons were performed in subgroups of patients with 2‐3 prior lines of therapy who were not refractory to bortezomib. The overall response rate (ORR) was 69.9% (95% confidence interval [CI], 61.7‐77.2) for Kd70 QW and 72.4% (95% CI, 65.9‐78.2) for Kd56 BIW. Median progression‐free survival (PFS) was 12.1 months (95% CI, 8.4‐14.3) for Kd70 QW and 14.5 months (95% CI, 10.2—not evaluable) for Kd56 BIW. Frequency of grade ≥ 3 adverse events (AEs) was 67.6% for Kd70 QW and 85.3% for Kd56 BIW. Regression analyses (adjusting for prognostic factors) of all patients in the trials who received Kd70 QW vs Kd56 BIW estimated a PFS hazard ratio of 0.91 (95% CI, 0.69‐1.19; P = .47) and an ORR odds ratio of 1.12 (95% CI, 0.74‐1.69; P = .61). These results suggest that Kd70 QW has a comparable efficacy profile compared with Kd56 BIW and represents a convenient and well‐tolerated treatment for patients with RRMM.

Background Venetoclax (Ven) is a selective, small molecule inhibitor of anti-apoptosis protein Bcl-2 that has antitumoral activity against multiple myeloma (MM), notably those with translocation t(11;14). Dexamethasone (d) has shown to enhance the expression of BCL-2 and pro-apoptotic protein Bim, shifting its binding towards Bcl-2 and sensitizing MM cells to Ven. This Phase 1/2 open-label trial is evaluating the safety and efficacy of the combination of Ven+d as a therapeutic approach to improve clinical outcomes in patients with t(11;14) Relapsed/Refractory (R/R) MM. Methods This ongoing study (NCT01794520) has 2 distinct phases. Phase 1 (P1) consisted of separate dose escalation, safety expansion, and Ven+d combination cohorts. The phase 2 (P2) portion is an expansion cohort of Ven+d to further evaluate its efficacy. The safety and efficacy of the Ven+d cohorts from P1 and P2 are reported here. Eligible patients (pts) were adults with t(11;14) R/R MM ≥18 years of age. Key eligibility criteria for the Ven+d cohort in P1 included prior treatment with a proteasome inhibitor (PI) and an immunomodulatory drug (IMID), and an ECOG score ≤1. In P2, eligibility included an ECOG score ≤2, disease progression on or within 60 days from the last dose on previous treatment and having received at least two lines of therapy with a PI, IMID, daratumumab, and glucocorticoids. Additional inclusion criteria for both phases included measurable disease and adequate bone marrow function in all pts, and the presence of t(11;14) determined by fluorescence in-situ hybridization. In both phases, pts received oral Ven 800 mg/day + oral d 40 mg (20 mg for pts ≥75 years of age) on days 1, 8, and 15 of each 21-day cycle. In P1, preliminary efficacy was assessed as the overall response rate (ORR), time to progression (TTP), progression free survival (PFS), and duration of response (DOR) of Ven+d based on the 2011 International Uniform Response Criteria for MM. Efficacy in P2 further evaluated ORR, very good partial response (VGPR) or better, PFS, DOR, TTP, and overall survival (OS) using 2016 IMWG response criteria. Results In P1, as of 15thApril, 2019, 20 pts were enrolled (17 [85%] male; median age, 63 years [range, 46-77]). The median number of prior therapies received was 2.5 (range: 1-7). Nineteen pts (95%) discontinued the study (18 due to progressive disease and 1 underwent transplant). The treatment-emergent adverse events (TEAEs) are summarized in the Table. Most frequent TEAEs were insomnia (45%), hypophosphatemia (40%), hyperglycemia (35%), diarrhea (35%), and thrombocytopenia (30%). Predominant Grade 3 or 4 TEAEs included neutropenia (21%), lymphopenia (29%), and hypophosphatemia (20%). The most common serious TEAE was tumor lysis syndrome (TLS) (10%). No deaths were reported in the treatment-emergent period. ORR was achieved by 13 (65%) and ≥VGPR was achieved by 6 (30%) pts respectively. Partial response (PR) was observed in 7 (35%) pts and stable disease (SD) in 4 (20%) pts. Median time to first response was 1.4 mos (95% CI: 0.7, 2.8). The DOR was 13.1 mos (95% CI: 10.9, 21.9). Median PFS and TTP were both 12.4 mos (95% CI 3.6, 20.9). In P2, as of March 18, 2019, 31 pts were enrolled (18 [58%] male; median age, 65 years [range, 48-80]). The median number of prior therapies received were 5 (range: 1-9). Eight (26%) pts discontinued the study (6 deaths, 1 withdrew consent, 1 due to physician's decision). The most frequent TEAEs reported were diarrhea (32%), nausea (26%) and lymphopenia (32%). The most frequent Grade 3 or 4 TEAEs were lymphopenia (32%), thrombocytopenia (11%), and hypertension (10%). Most common serious TEAE was sepsis (10%). Six (19%) deaths were reported (5 due to progressive disease and 1 due to adverse event). In the intention to treat population, the median TTR was 0.7 mos (range: 0.6-1.5). ORR was achieved by 14 (45%) and &gt;VGPR was observed in 8 (26%) pts. PR was observed in 6 (13%) pts and SD in 8 (26%) pts. Median PFS, DOR, and OS were not reached at the time of data analysis. The 9-mo estimates for PFS, DOR, and OS were 57% (95% CI: 19% 82%), 66% (95% CI: 16%, 91%), and 71% (95% CI: 44%, 87%) respectively. Conclusion In both phases of this study, Ven+d was efficacious and demonstrated tolerable safety in pts with t(11;14) R/R MM. These results support further investigation of Ven combinations in this pt population. This combination is also being investigated in the ongoing Phase 3 trial M13-494 (CANOVA) in t(11;14) positive R/R MM. Disclosures Kaufman: Takeda: Consultancy; Pharmacyclics: Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy; Bristol-Myers Squibb: Consultancy; Incyte: Consultancy; Karyopharm: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria; AbbVie: Consultancy; Winship Cancer Institute of Emory University: Employment; Amgen: Consultancy; TG Therapeutics: Consultancy. Gasparetto:Celgene: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; Janssen: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed ; BMS: Consultancy, Honoraria, Other: Travel, accommodations, or other expenses paid or reimbursed . Schjesvold:Takeda: 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; Novartis: Honoraria; Oncopeptides: Membership on an entity's Board of Directors or advisory committees; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; MSD: Membership on an entity's Board of Directors or advisory committees; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; SkyliteDX: Honoraria. Moreau:Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Facon:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees. Boise:Genentech Inc.: Membership on an entity's Board of Directors or advisory committees; AstraZeneca: Honoraria, Research Funding. Alzate:AbbVie Inc: Employment, Other: Stock/stock options. Macartney:AbbVie Inc: Employment, Other: Stock/stock options. Pesko:AbbVie: Employment, Other: Stock/stock options. Salem:AbbVie: Employment, Other: Stock/stock options. Ross:AbbVie: Employment, Other: Stock/stock options. Hong:Genentech Inc.: Employment, Equity Ownership; Roche: Equity Ownership. Maciag:AbbVie: Employment, Other: Stock/stock options. Pauff:AbbVie Inc: Employment, Other: may own stock or stock options. Kumar:Takeda: Research Funding; Celgene: Consultancy, Research Funding; Janssen: Consultancy, Research Funding. OffLabel Disclosure: Venetoclax is a BCL-2 inhibitor that is FDA-approved in some indications. This presentation will focus on venetoclax for treatment in multiple myeloma, which is not an approved indication.

Introduction: Daratumumab, a CD38-directed monoclonal antibody, in combination with lenalidomide and dexamethasone (D-Rd), recently received FDA approval for the treatment of patients with newly diagnosed multiple myeloma (NDMM) ineligible for autologous stem cell transplantation (ASCT). FDA approval was based on results of the prespecified interim analysis of a pivotal phase III trial (MAIA) in which D-Rd was compared to Rd among patients with NDMM who were ineligible for ASCT. In the MAIA trial, D-Rd significantly reduced the risk of progression or death compared to Rd. However, no trials have compared D-Rd to other standard-of-care (SOC) regimens. The present study compared progression-free survival (PFS) of D-Rd from the MAIA trial database to common SOC regimens from the Flatiron Health EHR Database, a de-identified nationwide US database of records primarily from community-based oncology practices. Methods: Patient-level data were obtained from the MAIA trial and the Flatiron database. Patients in the MAIA trial were enrolled between March 2015 and January 2017. To be included in MAIA, patients had to be deemed ineligible for high-dose chemotherapy with ASCT due to either age (≥65 years) or presence of comorbidities, have Eastern Cooperative Oncology Group performance status (ECOG PS) ≤2, creatinine clearance ≥30mL/min, and adequate bone marrow reserve. In the Flatiron Database, patients had to be diagnosed with MM between January 2011 and April 2019, age ≥65 years at initiation of first line treatment (LOT1), could not have received stem cell transplant as part of LOT1, and met MAIA inclusion/exclusion criteria. Regimens received by fewer than 10% of patients in Flatiron were excluded due to sample size and statistical power considerations. Bortezomib-lenalidomide-dexamethasone (VRd), bortezomib-dexamethasone (Vd), and Rd were the most commonly used regimens in non-transplant NDMM patients, representing 67% of regimens used in this setting. Multiple imputation by chained equations was used to address missing data in Flatiron. Eligible Flatiron patients treated with VRd, Vd, or Rd as LOT1 were reweighted to resemble the MAIA trial population on measured baseline characteristics using propensity-score (PS) weighting. An anchored adjusted indirect treatment comparison (ITC) was performed to compare D-Rd to VRd and D-Rd to Vd, using a stratified Cox proportional hazards regression model with Rd as the common anchor across both data sources. The model calculates hazard ratios (HRs) for direct comparisons within MAIA (D-Rd vs Rd) and within Flatiron (VRd vs. Rd, Vd vs. Rd) to estimate the HRs indirectly for D-Rd vs. VRd and D-Rd vs. Vd. Results: After application of MAIA inclusion criteria and PS-reweighting, the Flatiron VRd, Rd, and Vd patients resembled the MAIA trial population on baseline patient demographics and clinical characteristics (Table 1). D-Rd statistically significantly reduced the risk of progression or death compared to Rd (HR=0.55; 95% CI, 0.41-0.72) based on the direct comparison with D-Rd using the MAIA trial data; D-Rd statistically significantly reduced the risk of progression or death compared to VRd (HR=0.66; 95% CI, 0.46-0.95) and Vd (HR=0.47; 95% CI, 0.33-0.67) based on the anchored ITC (Figure 1). Sensitivity analyses will be performed and updated analysis using longer follow-up data from the MAIA study will be presented at the meeting. Conclusion: This analysis demonstrated that D-Rd reduced the risk of progression or death compared to other SOCs VRd and Vd for patients with NDMM who are transplant-ineligible. In the absence of head-to-head trials, this type of patient-level analysis provides important information that can help optimize treatment for patients with NDMM who are transplant-ineligible. Disclosures Durie: Amgen, Celgene, Johnson & Johnson, and Takeda: Consultancy. Kumar:Takeda: Research Funding; Janssen: Consultancy, Research Funding; Celgene: Consultancy, Research Funding. Usmani:Amgen, Celgene, Janssen, Sanofi, Takeda: Speakers Bureau; Amgen Array Biopharma, Bristol-Myers Squibb, Celgene, Janssen, Merck, Pharmacyclics, Sanofi, Takeda: Other: Research Grant; Amgen, Bristol-Myers Squibb, Celgene, Janssen, Merck, SkylineDX, Takeda: Other: Consultant/Advisor. Ammann:Janssen: Employment, Equity Ownership. Lam:Janssen: Employment, Equity Ownership. Kobos:Janssen: Employment. Maiese:Janssen: Employment, Equity Ownership. Facon:Celgene: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Takeda: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Amgen: Membership on an entity's Board of Directors or advisory committees; Sanofi: Membership on an entity's Board of Directors or advisory committees.