P-178: Evolution of the Multiple Myeloma Treatment Landscape in Portugal: a 5-year longitudinal analysis of treatment patterns in nationwide clinical practice

Introduction: The treatment pattern evolution for Multiple Myeloma (MM) in Portugal remains unclear, particularly how therapeutic innovation impacted clinical practice. This study aimed to describe and characterize MM treatment landscape over a 5-year period in Portugal.

Methods: A retrospective longitudinal multicenter study was conducted through secondary data from electronic health records of 11 Portuguese National Health Service hospitals between Sep/2017-Aug/2022. MM patient population was identified based on drug consumption data of MM-specific therapies (e.g., proteasome inhibitors, immunomodulators, anti-CD38 mAbs). Patient drug consumption profile was analyzed, and MM treatment regimens identified through clustering of concomitant antineoplastic drugs. Treatment patterns were characterized based on patient dynamics (naïve, ongoing, switch, drop-out), stem cell transplant (SCT) eligibility (eligible (SCT-E) vs non-eligible (SCT-NE)), and treatment lines (1L to 4L+). Outcomes included population characterization (patient number, age, sex (M:F) ratio), regimen patient share per treatment line and dynamic subgroups. Time-to-event analysis was carried between two consecutive 5-year time series (Sep/2012-Aug/2017 and Sep/2017-Aug/22) to estimate variation in treatment duration (TD) and time to next treatment (TTNT).

Results: The treated MM population increased by 53% during the 5-year period (2017: N=825; 2022: N=1266). Age and sex distribution remained stable, with a median age of 70 years and 1,2:1 sex ratio in 2022. Naïve patients increased by 22%, averaging a 5% yearly growth, with no major shift in SCT eligibility split (1:1 ratio in 2022).
Treatment line analysis showed a positive trend in patients achieving 3L+, with an increase of 12% to 21% from 2017 to 2022. Treatment drop-out decreased in 2L to 3L and 3L to 4L+, with a drop-out rate of 17% and 19% per switch subgroup, respectively, in 2022.
Main 1L regimens in SCT-E (VCd and VTd) and SCT-NE subgroups (VMP and VCd) remained stable, with daratumumab-based regimens increase in 2022 in all subgroups. Patient share in maintenance therapy increased from 5% to 16% in the overall treated population, dominated by lenalidomide in 2022. The 2L and 3L treatment pattern changed considerably, with daratumumab-based regimens dominating patient share in 2022 (2L-43%; 3L-35%). In 4L+ a heterogenous treatment pattern emerged, with no standard of care identified, being carfilzomib- and daratumumab-based regimens the most relevant in 2022.
Overall median TD increased in SCT-E subgroup from 5 to 19 months between time series, driven by maintenance therapy, and remained stable for SCT-NE patients (10 months). Regarding TTNT, median time increased between 3L to 4L+ in SCT-E patients from 5.5 to 9 months.

Conclusions: MM treatment landscape changed during a 5-year period, characterized by an increase in treated patients, patients achieving advanced treatment lines, and improved access to therapeutic innovation in earlier treatment stages of the disease.