Single‐agent lenalidomide maintenance after upfront autologous stem cell transplant for newly diagnosed multiple myeloma: The MD Anderson experience

Abstract

AbstractThe optimal duration of lenalidomide (Len) maintenance for patients with multiple myeloma (MM) after autologous stem cell transplantation (autoHCT) is unknown. We conducted a retrospective single‐center analysis of adult MM patients that received upfront autoHCT between 2005 and 2021, followed by single‐agent Len maintenance. A total of 1167 patients were included with a median age of 61.4 (range 25.4–82.3) years, and high‐risk chromosomal abnormalities in 19%. Median duration of maintenance was 22.3 (range 0.03–139.6) months. After a median follow‐up of 47.9 (range 2.9–171.7) months, median PFS and OS for the entire cohort were 56.6 (95% CI 48.2–61.4) months and 111.3 (95% CI 101.7–121.5) months, respectively. In MVA, high‐risk cytogenetics was associated with a worse PFS (HR 1.91) and OS (HR 1.73) (p < .001 for both). Use of KRD induction and achievement of MRD‐negative ≥ VGPR before autoHCT were associated with an improved PFS (HR 0.53 and HR 0.57, respectively; p < .001 for both). Longer maintenance duration, even with a 5‐year cutoff, was associated with superior PFS and OS (HR 0.17 and 0.12, respectively; p < .001 for both). A total of 106 patients (9%) developed a second primary malignancy (SPM), mostly solid tumors (39%) and myeloid malignancies (30%). Longer maintenance duration was associated with a higher risk of SPM, reaching statistical significance after >2 years (odds ratio 2.25; p < .001). In conclusion, outcomes with Len maintenance were comparable to those reported in large clinical trials. Longer duration of maintenance, even beyond 5 years, was associated with improved survival.