Transfusion Independence Corresponds With Survival in Patients With Lower-Risk Myelodysplastic Syndrome: Real-World Evidence From United States Insurance Claims.

Background: Most patients with lower-risk myelodysplastic syndromes (LR-MDS) develop red blood cell transfusion dependence (RBC-TD). RBC-TD has been associated with decreased quality of life and overall survival (OS).

Methods: This study assessed association between RBC-TD and survival using International Classification of Diseases, Tenth Revision (ICD.10), codes and patterns of MDS medication from a large US health insurance claims database (October 2015-March 2023) in 6531 patients who received ≥1 line of treatment.

Results: Erythropoiesis-stimulating agent and hypomethylating agent monotherapy were treatments most commonly used in first-line (1L) and second-line (2L) settings. At baseline, 8% of patients had high transfusion burden (≥8 RBC U/8 weeks). In 1L and 2L, ≥16-week RBC transfusion independence (TI) was achieved by 41% (n = 935/2301) and 32% (n = 239/745) of patients, respectively. Median real-world progression-free survival (rwPFS; time from start of treatment to next treatment or progression/death, whichever occurred first) and median OS (mOS) were significantly longer in ≥16-week RBC-TI responders than nonresponders. Median (95% confidence interval [CI]) rwPFS in 1L responders versus nonresponders was 18.0 months (17.0-19.3) versus 3.3 months (3.0-3.5; P < .0001), respectively, and was 20.5 months (17.6-23.7) versus 4.1 months (3.7-4.6; P < .0001), respectively, in 2L. mOS (95% CI) in 1L responders versus nonresponders was 28.7 months (26.1-31.6) versus 8.0 months (7.0-9.1; P < .0001), respectively, and 45.2 months (35.9-49.8) versus 9.0 months (7.6-10.6; P < .0001), respectively, in 2L. RBC-TI achievement was associated with improved survival.

Conclusions: Results suggest RBC-TD may be a modifiable factor corresponding to clinical outcomes in LR-MDS, further supporting RBC-TI as a primary endpoint in clinical studies.