Response To First-Line Treatment In Stem Cell Transplant (SCT) and Non-SCT Patients With Newly Diagnosed Multiple Myeloma Who Are Enrolled In The Connect MM Registry
Authors: Abonour Rafat , Shah Jatin J. , Durie Brian , Terebelo Howard , Gasparetto Cristina J , Mehta Jayesh , Narang Mohit , Thomas Sachdev P , Toomey Kathleen , Sullivan Kristen A , Srinivasan Shankar , Nagarwala Yasir , Rifkin Robert M 
Published: October 2019

Abstract

Introduction
The advent of new therapies for the treatment of multiple myeloma (MM) has resulted in improved clinical outcomes and patient (pt) survival. However, the best combination of agents from different drug classes and subsequent therapeutic strategies for pts with newly diagnosed MM (NDMM), while investigated, has not yet been established. The goal of the Connect(R) MM registry is to provide insight into the disease and explore the management and outcomes of pts with NDMM who are treated at community and academic sites in the United States. This analysis aims to describe the combinations used in NDMM outside the interventional clinical trial setting and the activity and outcome response to different regimens by class of therapeutic agents in clinical practice.

Methods
Connect MM is an ongoing prospective, longitudinal, observational registry of NDMM pts. This multicenter US pt registry was initiated in 2009. Pts who were newly diagnosed with symptomatic MM within 2 months of enrollment were eligible to participate. Data were collected at baseline and every 3 months. Pts who had response data 12 months after enrollment, met CRAB criteria, and received treatment were eligible for this analysis. Treated pts were stratified according to SCT status. Data on baseline demographic and clinical characteristics, and initial therapies (proteasome inhibitors [PI], IMiD(R) immunomodulating agents, alkylating agents [AA], corticosteroids, and combinations) were collected. The overall response rate (ORR), as assessed by the site investigator, was defined as the best response during the course of initial therapy and is presented as cumulative ORR over 3, 6, and 12 months.

Results
As of the data cutoff (April 15, 2013), 1494 pts were enrolled in the registry; 1312 pts met CRAB criteria and received treatment. Of these, 439 received SCT or were anticipated to receive (had undergone a stem cell harvest) SCT and 873 would not receive SCT (non-SCT). Mean (SD) age for SCT and non-SCT pts was 58.9 years (8.7) and 69.8 years (10.7), respectively. Majority of pts in both groups were male (62.0% vs 56.5%) and Caucasian (85.4% vs 81.4%). Among SCT pts, ISS stages were: I/II (55.1%), III (25.3%), and unknown (19.6%) and ECOG performance status (PS) was 0/1 (63.1.%), 2/3 (7.1%), and unknown (29.8%). Among non-SCT pts, ISS stages were: I/II (42.0.%), III (32.2%), and unknown (25.8%) and ECOG PS was 0/1 (56.6%), 2/3/4 (14.7%), and unknown (28.8%). ORR to initial therapy and 1-year survival for the 5 most commonly used regimens are presented in the Table.
A triplet regimen is 2 times more likely to be selected for SCT pts than for non-SCT pts, suggesting investigator bias in selecting more aggressive therapy for younger pts. For the 5 most commonly used regimens, 1-year survival was 97.9% for SCT pts and 83.3% for non-SCT pts.

Conclusion
Outside an interventional clinical trial setting, the most commonly used initial treatment regimens for NDMM were IMiD + PI + steroid for SCT pts and PI + steroid for non-SCT pts. Response rates were higher among SCT pts regardless of regimen. The investigator-assessed response rates were similar across the various combinations including 2 vs 3 drug combinations in SCT pts.

Disclosures:
Abonour: Celgene: Honoraria, Research Funding; Millennium: Honoraria, Research Funding; Onyx: Honoraria, Research Funding. Off Label Use: This abstract will report on an observational study. There is no pre-specified use of drugs; treating physicians determined what drugs to use and some could be off-label. Shah:Millenium: Consultancy, Research Funding; Novartis: Consultancy, Research Funding; Celgene: Consultancy, Research Funding; Array: Consultancy, Research Funding; Onyx: Consultancy, Research Funding. Durie:Celgene: Consultancy; Millennium: Consultancy; Onyx: Consultancy. Terebelo:Amgen: Honoraria; Millennium: Honoraria. Gasparetto:Celgene ( 2012): Membership on an entity's Board of Directors or advisory committees, Research Funding, Speakers Bureau; Millennium (2012): Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Onyx: Membership on an entity's Board of Directors or advisory committees. Mehta:Celgene: Speakers Bureau; Millennium: Speakers Bureau. Narang:Celgene: Membership on an entity's Board of Directors or advisory committees. Toomey:Celgene: Consultancy. Sullivan:Celgene: Employment. Srinivasan:Celgene: Employment. Nagarwala:Celgene: Employment. Rifkin:Celgene: Consultancy, Honoraria; Millennium: Consultancy, Honoraria; Onyx: Consultancy, Honoraria.