INTRODUCTION: Improvement in outcomes in relapsed/refractory multiple myeloma (RRMM) remains an area of unmet need, yet there is a shortage of data describing typical management of these patients in real-world settings. Such data may inform health technology assessments and other regulatory evaluations of RRMM therapies. To help address this information gap, we analyzed data from an RRMM cohort in the United Kingdom (UK).
METHODS: A retrospective medical record review was conducted in 216 patients with RRMM in the UK. All patients were ≥18 years of age at initial MM diagnosis and first diagnosed with RRMM (during or following first-line induction therapy) between 01-Jan-2009 and 31-Dec-2011. Patients were retrospectively assessed on second- and third-line treatment regimens received, treatment duration, and reasons for treatment discontinuation from date of first relapse/progression (i.e., RRMM diagnosis).
RESULTS: Mean (SD) age at first relapse was 65.6 (8.7) years, with approximately half (53%) having advanced age (≥65 years). The sample was 63% male and 69% were still alive at the time of medical record review. Among all patients, 208 (97%) received ≥1 line of chemotherapy after first relapse; 94 (43%) received ≥2 lines after first relapse. The most common second-line regimen was bortezomib + dexamethasone with or without other agents (66% of second-line initiators), followed by lenalidomide + dexamethasone with or without other agents (20%). Median duration of second-line treatment was 6 cycles over a median of 5.4 months. Among the 98% of patients who discontinued second-line treatment, a majority (62%) stopped due to reaching a perceived maximal response with no additional benefit expected; 33 patients (16%) discontinued due to disease progression and 8% discontinued due to toxicities. Lenalidomide + dexamethasone with or without other agents was the predominant third-line regimen (67% of third-line initiators). Among the 94 patients receiving third-line treatment, median duration was 6 cycles over a median of 5.7 months. The leading reason for third-line discontinuation was disease progression (48%); 30% discontinued because they reached a perceived maximal response with no anticipated additional benefit, and 20% discontinued because of loss or lack of response.
CONCLUSIONS: In the RRMM cohort reviewed, bortezomib-containing regimens were the predominant second-line therapy and lenalidomide + dexamethasone was the most common third-line regimen. The most common reason for discontinuation in RRMM treatment was reaching a perceived maximal response with no additional benefit expected; disease progression was also a common discontinuation reason. With growing evidence that treatment to progression may be superior to a fixed therapy duration, the relatively short treatment duration reported here (<6 months) highlights a potential under treatment and unmet need in current RRMM therapy.
