Front-Line (FL) Treatment Patterns Associated with Elderly Newly Diagnosed Multiple Myeloma (MM) Patients Treated in the US Community Setting

Background:

Treatment of MM has undergone dramatic changes in the past decade. However, few studies have focused on treatment patterns among elderly patients. The present study sought to describe contemporary FL treatment patterns among elderly MM patients in a community practice setting.

Methods:

A retrospective cohort study of patients (≥65 years old) with newly diagnosed MM between 7/1/2011 and 5/31/2014 who had ≥1 oncologist visit 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. Baseline demographics and clinical characteristics were compared between treated patients and patients who did not receive anti-MM treatment in the EMR network (untreated). FL treatment included all anti-MM agents received from first anti-MM prescription/administration after initial diagnosis until the initiation of second-line treatment, which was defined as the first day of any gap in treatment >90 days or initiation of a new regimen. FL treatment patterns were characterized based on descriptive analyses of the EMR data. Time from diagnosis to FL therapy initiation and duration of FL treatment were analyzed using Kaplan-Meier (K-M) methods.

Results:

A total of 3,768 patients met eligibility criteria: 2,896 (77%) initiated systemic FL therapy (median age 75 years, 56% male) and 872 (23%) were untreated (median age 76 years, 49% male; Table 1). The K-M estimate of treatment rate at 12 months from MM diagnosis was 76% (Table 2). With a median follow-up of 13.2 months, 55% of patients had discontinued FL, while 34% remained on FL. Treated patients were younger (mean age 75.4 years versus 76.4 years, P<0.001) and had fewer baseline comorbidities (P=0.001) than untreated patients. The proportion of males was higher in the treated group (P=0.002).

Of the 2,896 treated patients, 13% received a stem cell transplant at any time. Median time from diagnosis to FL therapy initiation was 28 days (95% CI 25-31; Table 2). The most common FL therapy was bortezomib +/- steroids (44%), followed by steroids only (14%), lenalidomide +/- steroids (13%), bortezomib + lenalidomide +/- steroids (10%), bortezomib + cyclophosphamide +/- steroids (8%), carfilzomib- or pomalidomide-containing regimens (4%), and conventional chemotherapy (4%). During FL therapy, 14% switched therapies. 17% of those who were treated with bortezomib + lenalidomide +/- steroids and 10% of those treated with bortezomib + cyclophosphamide +/- steroids received maintenance therapy. Median duration of FL treatment was 196 days (95% CI 180-208; Table 2).

Conclusions:

Results suggest that almost one-quarter of elderly patients newly diagnosed with MM remain untreated. In addition, about 20% of those treated in FL received suboptimal therapy (i.e., chemotherapy or steroids). Despite the advances in the treatment of MM with the availability of proteasome inhibitors/immunomodulatory agents, there still seems to be an unmet need in this patient population for novel therapies in the FL setting, especially for elderly patients who are at higher risk of comorbidities and clinical complications.