Real-world treatment patterns and outcomes of triple-exposed multiple myeloma patients treated in community oncology practices in the United States.
Authors: Smith Robert , Xue Mei , Dorrow Natalie , Varughese Prateesh , Hogea Cosima , Buckingham Trudy , Sansbury Leah , Ferrante Shannon , Maiese Eric M. 
Published: June 2021

e18727 Background: Treatment for multiple myeloma (MM) over the past decade has significantly improved survival. In particular, 3 drug classes have altered the treatment paradigm for MM patients: proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), and CD38 monoclonal antibodies (anti-CD38s). Despite these advances, the majority of patients with MM will become refractory to PIs, IMiDs, and anti-CD38s, and limited evidence indicates these patients have poor outcomes. A retrospective study in the US showed that 275 patients treated at 14 academic institutions with prior exposure to a PI, IMiD, and anti-CD38 had median overall survival of 9.2 months. The aim of this study was to evaluate real-world treatment patterns and outcomes (duration of therapy and overall survival) of patients who had been treated with a PI, IMiD, and anti-CD38 in community practices in the US. Methods: This retrospective observational study was conducted using the Integra Connect (IC) database. The IC database includes electronic health data from structured and unstructured fields from 12 community practices on the East and West Coast of the US. Adult patients with ≥2 ICD-9/ICD-10 codes for MM on at least 2 separate dates, who received MM treatment between Jan 1, 2016, and Dec 31, 2019, with treatment history that included at least one PI, one IMiD, and one anti-CD38 (triple exposed), and initiated a subsequent line of therapy (s-LOT) after becoming triple exposed, were included. Duration of length of s-LOT was defined as number of days from start of s-LOT to last-day supply of s-LOT. Overall survival was defined as the length of time from start of s-LOT through death or the date of the last office visit. Results: A total of 501 patients were included in this analysis. The median age of patients was 64.9 years; 50% were male; 50% had commercial insurance. 82.8% of patients had ECOG 0 or 1 at diagnosis and had received a median of 3 prior lines of therapy (LOTs) before initiating s-LOT. Prior to initiating s-LOT, 91% had been exposed to bortezomib, 81% to carfilzomib, 94% to lenalidomide, 82% to pomalidomide, and 100% to daratumumab. In s-LOT, 95% received treatment that included same drug or same drug class (30% received bortezomib, 48% carfilzomib, 31% lenalidomide, 47% pomalidomide, and 31% daratumumab). The median duration of s-LOT was 78 days and median survival was 10.3 months (308 days) from initiation of s-LOT. Conclusions: For triple-class exposed patients, there is a lack of consensus on the most efficacious approach to subsequent treatment. The present study shows a significant amount of retreatment with previously used agents or classes among these patients with short duration of therapy and poor survival. As has been previously noted, new strategies and agents targeting novel aspects of MM are needed to improve outcomes for these patients. Disclosures: This study (213286) was sponsored by GlaxoSmithKline.