OBJECTIVES:  MDS encompasses multiple, rare hematological stem cell disorders resulting in cytopenias and disease-related complications/deaths. Overall of the two HMAs approved, only azacitidine has been shown to impact survival; no approved therapies exist post 1LT progression. We examined treatment patterns after ending 1LT in HR-MDS patients in routine care. METHODS: Adult HR-MDS patients initiating 1LT (1/1/2008 - 7/31/2015) were identified from a large US EMR database. As complete cytogenetics were unavailable, HR-MDS was based on: International Classification of Diseases (ICD) coding of HR-MDS (with ³1 HR-MDS code [ICD-9 code: 238.73; ICD-10 codes: D46.20, D46.21, D46.22]) or HR-MDS algorithm based on Revised International Prognostic Scoring System. 1LT was defined as MDS-specific treatment (MDS-Tx) initiated after the first HR-MDS claim; the addition/substitution of an MDS-Tx >28 days post 1LT triggered second-line therapy (2LT). MDS-directed supportive care (MDS-SC) included erythrocyte or platelet transfusions, erythropoietic-, and granulocyte-stimulating agents. Patients were followed until death, progression to acute myeloid leukemia (AML), loss to follow-up, or end of study. RESULTS: CONCLUSIONS: A majority of HR-MDS patients in routine care do not receive 2LT with an MDS-Tx. Of those who receive MDS-Tx, HMAs remain the predominate choice. MDS-SC post 1LT progression is still utilized in most patients. Outcomes in patients not initiating 2LT are poor, highlighting the need for additional treatment options.