Long-term Outcomes in Patients With Multiple Myeloma: A Retrospective Analysis of the Dutch Population-based HAematological Registry for Observational Studies (PHAROS).

Registry data are important for monitoring the impact of new therapies on treatment algorithms and outcomes, and for guiding clinical decision making in multiple myeloma (MM). This observational study analyzed real-world data from patients in the Population-based HAematological Registry for Observational Studies who were treated for symptomatic MM from 2008 to 2013 in the Netherlands. The primary endpoint was overall survival (OS) from initiation of first-line treatment. Secondary endpoints included OS and progression-free survival per treatment line, treatment patterns, and treatment response. Between 2008 and 2013, 917, 583, 283, and 139 patients had initiated first, second, third, and fourth treatment lines, respectively. Thalidomide-based regimens were the most frequently used first-line treatment (66%); bortezomib- and lenalidomide-based regimens were most often used in the second line (41% and 27%, respectively). The median OS (95% confidence interval) ranged from 37.5 months (34.8-41.8 months) in the first line to 9.2 months (6.2-12.3 months) in the fourth line. Univariate analyses showed that survival benefits were most apparent in younger patients (≤65 vs >65 years). These analyses provide important real-world information on treatment patterns and outcomes in patients with MM.