Ixazomib Plus Lenalidomide-Dexamethasone (IRd) in Relapsed/Refractory Multiple Myeloma (MM) Patients (Pts) - Effectiveness in Routine Clinical Practice Is Similar to the Efficacy in the Phase 3 Tourmaline-MM1 Trial: A Pooled Analysis from the Insight MM Observational Study and the Czech Registry of Monoclonal Gammopathies (RMG) (2018)

Abstract Background Ixazomib (ixa), the first oral proteasome inhibitor, is approved in combination with lenalidomide (len)-dexamethasone in &gt;50 countries globally, including the US and EU, for the treatment of relapsed/refractory MM (RRMM) pts who have received ≥1 prior therapy. Outcomes and tolerability in routine clinical practice often differ from data reported in clinical trials for novel-agent-based MM therapies; however, data directly comparing efficacy in clinical trials with effectiveness in routine clinical practice of new MM agents and regimens are currently limited. To evaluate the effectiveness of IRd in RRMM pts in routine clinical practice, we performed a pooled analysis of individual pt-level data for IRd-treated RRMM pts from the ongoing INSIGHT MM (NCT02761187) study and from the Czech RMG. INSIGHT MM is the largest global, prospective, observational MM study conducted to date, which is currently enrolling ~4200 adult pts with newly diagnosed MM or RRMM from Europe (EUR), the US, Asia, and Latin America. The Czech RMG was established by the Czech Myeloma Group in 2007 and comprises clinical data for &gt;6000 MM pts enrolled at 19 Czech and 4 Slovak centers. Methods RRMM pts with 1-3 (INSIGHT MM) or ≥1 (RMG) prior therapies who had been treated with IRd were identified. INSIGHT MM pts required prospectively collected data on IRd therapy; pts who received another regimen or additional treatment within the same line of therapy as IRd were excluded. RMG pts from Czech centers who received IRd were included using the same eligibility criteria as the INSIGHT MM study. Individual pt-level data on demographics, disease characteristics, treatment history, effectiveness, and safety for IRd-treated RRMM pts from INSIGHT MM and the Czech RMG were integrated and analyzed. Best response and PFS were determined as per the assessment of the treating physician or local investigator, utilizing IMWG criteria. Descriptive analyses were performed on the integrated data as well as on data from INSIGHT MM and from the Czech RMG. PFS, TTNT, DOT, and OS were estimated using Kaplan Meier methodology. Results Overall, 163 IRd-treated RRMM pts from 9 countries were included in the analysis (50 INSIGHT MM, 113 Czech RMG); of these, 146 (90%) were from EUR, 16 (10%) from the US, and 1 (1%) from Taiwan. Median age was 67 (range 39-84) yrs, with 23 (14%) pts aged &gt;75 yrs; 86 (53%) pts were male. At initial diagnosis, 38%/36%/26% of pts had ISS Stage I/II/III disease; median time from diagnosis to initiation of IRd treatment was 42.6 mos; 71% of pts had ECOG PS ≥1. Most pts (65%) had IgG MM, and 14% had extramedullary disease. Overall, 50%/30%/20% of pts received IRd as 2nd/3rd/≥4th-line therapy. The most common reasons for starting IRd therapy were relapse/progression (90%), including bone lesions (53%), and anemia (14%). Overall, 61% of pts had received prior stem cell transplant; prior therapies included bortezomib (bor) in 89% of pts, thalidomide (thal) in 42%, len in 21%, carfilzomib (car) in 11%, daratumumab (dara) in 3%, and pomalidomide (pom) in 2%. Median DOT was 14.0 mos; 101 (62%) pts were on treatment at data cut-off. Data on best response to therapy were available for 105 pts; among these, ORR (partial response or better) was 74%, with 31% ≥VGPR (Table); ORR with IRd as 2nd/3rd/≥4th-line therapy was 91%/57%/47%, including 41%/25%/11% ≥VGPR. Median time to first response was 1.1 mos for Czech RMG pts; median time to best response was 3.7 mos for INSIGHT MM pts. Overall, median PFS was 20.9 (95% CI: 13.0-28.7) mos, with a 12-mo rate of 65% (Table). Median PFS with 2nd/3rd/4th/&gt;4th-line therapy was NR/23.2/14.2/5.1 mos. Median TTNT was 26.2 (95% CI: 9.6-42.8) mos, with a 12-mo rate of 73% (Table). Overall, 37 (23%) pts received subsequent therapies including bor (24%), pom (24%), thal (16%), dara (16%), car (14%), or len (8%). Median OS was not reached, with 81% of pts alive at 12 mos (Table). Ixa and len dose reductions were required in 15% and 30% of pts, respectively, with 11% and 21% of pts, respectively, requiring dose reductions due to AEs (Table). Conclusions These findings show that the effectiveness of IRd in routine clinical practice, including an ORR of 74% and a median PFS of 20.9 mos, is comparable to the efficacy of IRd reported in the TOURMALINE-MM1 trial (ORR 78%, median PFS 20.6 mos). IRd is well tolerated in RRMM pts treated in routine clinical practice, with low rates of dose reductions due to AEs for ixa (11%) and len (21%). Table. Table. Disclosures Hajek: Bristol-Myers Squibb: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding; Amgen: Consultancy, Honoraria, Research Funding. Terpos:Novartis: Honoraria; Celgene: 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, Other: Travel Grant, Patents &amp; Royalties; Genesis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Patents &amp; Royalties; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Research Funding. Lee:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Adaptive Biotechnologies Corporation: Consultancy; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; Chugai Biopharmaceuticals: Consultancy; Takeda Oncology: Consultancy, Membership on an entity's Board of Directors or advisory committees; Kite Pharma: Consultancy, Membership on an entity's Board of Directors or advisory committees. Chari:Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Adaptive Biotechnology: Membership on an entity's Board of Directors or advisory committees; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: 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; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Bristol Myers Squibb: Consultancy; Pharmacyclics: Research Funding; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees; The Binding Site: Consultancy; Array Biopharma: Research Funding. Costello:Poseida Therapeutics, Inc.: Research Funding; Takeda: Consultancy; Celgene: Consultancy. Puig:Takeda: Consultancy, Honoraria; Celgene: Honoraria, Research Funding; Janssen: Consultancy, Honoraria, Research Funding. Leleu:Celgene: Honoraria, Other: steering committee membership ; Janssen: Honoraria, Other; BMS: Honoraria, Other: steering committee membership ; Merk: Honoraria, Other: steering committee membership ; Takeda: Honoraria, Other: steering committee membership ; Amgen: Honoraria, Other: steering committee membership ; Sanofi: Honoraria, Other: steering committee membership steering committee membership ; Novartis: Honoraria, Other: steering committee membership ; Roche: Honoraria; Gilead: Honoraria; Incyte: Honoraria, Other: steering committee membership ; Karyopharm: Honoraria. Berdeja:Celgene: Research Funding; Sanofi: Research Funding; Glenmark: Research Funding; Bristol-Myers Squibb: Research Funding; Amgen: Research Funding; Takeda: Research Funding; Janssen: Research Funding; Novartis: Research Funding; Genentech: Research Funding; Bluebird: Research Funding; Teva: Research Funding; Poseida Therapeutics, Inc.: Research Funding. Davies:Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees; Janssen: Consultancy, Honoraria; Abbvie: Consultancy; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; MMRF: Honoraria; ASH: Honoraria; TRM Oncology: Honoraria; Celgene: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Weisel:Amgen, BMS, Celgene, Janssen, and Takeda: Honoraria; Amgen, Celgene, Janssen, and Sanofi: Research Funding; Amgen, BMS, Celgene, Janssen, Juno, Sanofi, and Takeda: Consultancy, Membership on an entity's Board of Directors or advisory committees. Usmani:Abbvie, Amgen, Celgene, Genmab, Merck, MundiPharma, Janssen, Seattle Genetics: Consultancy; Amgen, BMS, Celgene, Janssen, Merck, Pharmacyclics,Sanofi, Seattle Genetics, Takeda: Research Funding. Hungria:Janssen: Honoraria; Amgen: Honoraria; Takeda: Honoraria; Celgene: Honoraria. Boccadoro:Amgen: Honoraria, Research Funding; Sanofi: Honoraria, Research Funding; Janssen: Honoraria, Research Funding; Novartis: Honoraria, Research Funding; AbbVie: Honoraria; Bristol-Myers Squibb: Honoraria, Research Funding; Mundipharma: Research Funding; Celgene: Honoraria, Research Funding. Rifkin:McKesson: Equity Ownership; Boehringer Ingelheim: Consultancy; EMD Serono: Consultancy; Celgene: Consultancy; Takeda: Consultancy; Sandoz: Consultancy; Amgen: Consultancy. Zonder:Takeda: Honoraria; Pharmacyclics: Other: DSMC; Alnylam: Honoraria; Coelum: Honoraria; BMS: Research Funding; Janssen: Honoraria; Celgene: Consultancy, Honoraria. Cook:Amgen, Bristol-Myers Squibb