Luspatercept in transfusion-dependent myelodysplastic syndromes: real world data

Introduction Luspatercept reduced the severity of anemia in transfusion-dependent lower risk MDS with ring sideroblasts (RS) in the MEDALIST trial. Here we present real-world data in a prospective multicenter registry study of MDS patients treated with luspatercept (ChiCTR2300071857). Patients who were not enrolled in the MEDALIST trial were also evaluated, including those of higher IPSS-R risk, without ring sideroblasts, or failed to prior hypomethylating agent (HMA) therapy. Methods Eligible patients were ≥ 18 years old and were RBC transfusion-dependent (defined as ≥2 units of RBC transfusion per 8 weeks). Primary endpoint was RBC transfusion independence (RBC-TI) for ≥8 weeks. Secondary endpoints are hematological improvement-erythroid (HI-E, defined as >50% reduction in RBC transfusion), neutrophil (HI-N) and platelet (HI-P) per the IWG 2006 criteria. Results From June 2022 to August 2023, 25 patients were treated with luspatercept for a median of 7 cycles (Table 1). The median follow-up time was 19.4 weeks. The rate of RBC-TI was 36%. The median duration of RBC-TI was 227 [IQR: 129-324] days. The rates of HI-E, HI-N, HI-P were 52% (13/25), 21% (3/14) and 33% (5/15), respectively. Multi-variant analysis revealed that lower transfusion burden (<6 u/8w) favored higher RBC-TI rate (OR: 0.041, 95% CI: 0.003∼0.666, p=0.025), while other characteristics such as IPSS-R risk, presence of RS or SF3B1 and prior therapy had no impact on the outcome (Table 1). Conclusions Our real-world data confirms the clinical benefit of luspatercept observed in the MEDALIST trial. Luspatercept retains efficacy in patients without RS, or failed to prior HMA therapy.