An oBservational retrospective Analysis of treatment patternS and Effectiveness of standard of CAre for Multiple Myeloma Patients Exposed to Lenalidomide and a Proteasome Inhibitor: BasecaMMp Study

INTRODUCTION: Most patients with relapsed or refractory multiple myeloma (RRMM) have previously received lenalidomide (LEN) and proteasome inhibitors (PIs). This real-world study describes treatment patterns and clinical outcomes for RRMM patients post-LEN and PI in Germany. METHODS: The BasecaMMp cohort included patients with prior LEN and PI therapy within the first to third line of treatment (LOT) between May 2016 and December 2023. Patient characteristics, treatment regimens and progression-free survival (PFS), overall survival (OS) and time to next treatment (TTNT) were analyzed. RESULTS: Of 1834 patients included (median age: 72.5 years; 59.5% male; median of 2 prior LOTs), around 30.4% were double-refractory, and 47.7% were LEN-refractory. Index therapies (first therapies received after exposure to LEN and a PI in the first to third lines) were highly heterogeneous. Median PFS was 12.7 (95% confidence interval [CI], 12.2-13.14) months overall and 11.3 (95% CI, 10.3-12.1) months in LEN-refractory patients, while median OS was 37.1 (95% CI, 34.2-40.7) months overall and 34.3 (95% CI, 31.1-41.0) months in LEN-refractory patients. CONCLUSION: These findings highlight the lack of a clear standard of care, poor clinical outcomes, and the need for more effective therapies and treatment strategies for this population.