Treatment Sequencing Patterns Associated with Elderly Patients with Relapsed/Refractory Multiple Myeloma (MM) in the US Community Setting

Background:

With more targeted agents in development, the treatment of relapsed/refractory MM has become more complicated and, as a consequence, has resulted in great heterogeneity in treatment patterns. Little is known about treatment sequences in the US community practice setting for elderly patients. The goal of this study was to describe treatment sequencing patterns in elderly MM patients.

Methods:

A retrospective cohort study of patients (≥65 years old) with newly diagnosed MM between 7/1/2011 and 5/31/2014 who had ≥2 oncologist visits within 90 days after diagnosis and ≥90 days of follow-up was conducted. Patients were selected from the Truven MarketScan Oncology Electronic Medical Records (EMR) database and followed until last visit in the EMR database or 8/31/2014, whichever occurred first. First-line (1L) treatment included treatment that a patient received since first anti-MM prescription/administration. For any given line of therapy, the end of treatment was defined as the first day of any gap in treatment >90 days or initiation of a new regimen. Treatment patterns for 1L, second-line (2L), and third-line (3L) treatment were described. Duration of treatment and treatment-free intervals were analyzed using Kaplan-Meier (K-M) methods.

Results:

2,896 MM patients met the selection criteria and initiated anti-MM therapy in the study period. Of these, 1,032 (36%) patients (median age 75 years, 55% male) received 2L treatment and 352 (12%) received 3L treatment. The median patient follow-up for those who received 2L treatment was 19.2 months. Of the 1,032 patients with 2L treatment, 715 (69%) received a proteasome inhibitor (PI=bortezomib, carfilzomib) or an immunomodulatory drug (IMiD=lenalidomide, pomalidomide, thalidomide) and 317 (31%) received conventional chemotherapy (CT) or steroid (S) only (Table 1). 16% received a stem cell transplant at any time. Of the 352 patients with 3L treatment, 227 (64%) received a PI or IMiD, and 125 (36%) received CT or S only (Table 1). The use of carfilzomib and pomalidomide increased slightly from 1L to 3L (Table 2).

Of the 374 patients who received 2L IMiD, over 80% received a PI or IMiD in 1L treatment (PI: 45%, IMiD: 22%, both: 15%); of those who received an IMiD in both 1L and 2L, 86% repeated the IMiD received in 1L and 9% switched to pomalidomide. Of the 307 patients who received 2L PI, >80% received a PI or IMiD in 1L treatment (PI: 57%, IMiD: 22%, both: 5%); of those who received a PI in both 1L and 2L, 72% repeated the PI received in 1L and 26% switched to carfilzomib. Similarly, of the 124 patients who received 3L IMiD, most received a PI or IMiD in 2L (PI: 13%, IMiD: 47%, both: 3%). The same was true of the 92 patients who received 3L PI (PI: 28%, IMiD: 45%, both: 3% in 2L treatment). Of the 352 patients with 1L-3L treatment, 93% received a PI or IMiD in 1L, 2L, or 3L; 32% had a PI or IMiD in all 3 lines.

Median duration of 1L, 2L, and 3L treatment was 196, 148, and 124 days, respectively (Table 3). Median treatment-free interval from end of 1L to initiation of 2L, and from end of 2L to initiation of 3L, was 175 and 137 days, respectively (Table 3).

Conclusions:

The data suggest that elderly MM patients run out of treatment options when they fail 1L/2L treatment; therefore, duration of treatment as well as treatment-free interval decreases as disease progresses. These findings highlight the unmet needs for newer therapies in elderly MM patients who fail prior anti-MM treatment.