Clinical Outcomes in Patients With Refractory Anemia With Excess Blasts (RAEB) Who Receive Hypomethylating Agents (HMAs)

We used the Surveillance, Epidemiology and End Results (SEER) -Medicare database to understand the clinical effectiveness associated with use of hypomethylating agents for patients with refractory anemia with excess blasts in contemporary, representative real -world settings. Median survival for the overall population (n = 973) remained significantly shorter than in the AZA-001 clinical trial, highlighting how patient outcomes vary between clinical and real -world settings. Background: We sought to understand the clinical effectiveness associated with use of hypomethylating agents (HMAs) azacitidine (AZA) and decitabine (DEC) for patients with refractory anemia with excess blasts (RAEB; an established proxy for higher -risk myelodysplastic syndromes/neoplasms) in contemporary and representative real -world settings. Patients and methods: We used the Surveillance, Epidemiology and End Results (SEER) -Medicare database, a linkage of cancer registry and Medicare claims data, to identify patients aged >= 66 years diagnosed with RAEB, between 2009 and 2017 in the United States, and who received AZA or DEC as first -line therapy. Outcomes measured were overall survival (OS), event -free survival (EFS), and incidence of progression -related acute myeloid leukemia (AML). Results: Of 973 eligible patients, 738 (75.8%) received AZA and 235 (24.2%) received DEC; 6.4% received hematopoietic cell transplantation during follow-up. In the overall population, median OS was 13.9 months (95% confidence interval [CI]: 12.9-15.0), median EFS was 5.2 months (95% CI: 4.9-5.7), and 38.0% of patients progressed to AML. Incidences of AML progression and death were 25.6% and 29.9%, respectively, at Year 1, and 34.3% and 44.8%, respectively, at Year 2. There were no significant differences in clinical benefits between AZA and DEC. Conclusion: Median OS with both HMAs remained significantly shorter than in the AZA-001 clinical trial, highlighting how patient outcomes vary between clinical and real -world settings. Further research is required to understand why these disparities exist.