Response Assessment to Erythropoietin-Zeta (Epo-Alpha Biosimilar) Therapy in Low-Risk Myelodysplastic Syndromes

Background. This prospective observational study aimed to verify the efficacy of erythropoietin zeta in the treatment of patients with low-risk myelodysplastic syndrome. Methods. Patients with low/int-1 IPSS risk and serum erythropoietin level below 500 U/L were enrolled. Treatment consisted of erythropoietin zeta 40,000 U subcutaneously once a week. The primary endpoint was the erythroid response. According to Simon's two-stage statistical design, 36 patients were recruited. The median age was 75 years (range 56-83 years), male/female ratio was 1.1/1, median baseline serum erythropoietin was 57.9 U/L (range 9.4-475 U/L). 53% of patients had low-risk disease, while the remaining had Int-1 risk. Results. After 8 weeks, a significant response (rise in Hb levels of at least 1.5 g/dL) was achieved in 18 patients (50%) out of 36. However, 17 patients did not improve; 8/17 patients pursued the 40,000 U weekly schedule of erythropoietin zeta, and 4/8 (50%) of them reached the erythroid response after 16 weeks. Nine patients underwent dosage doubling (40,000 U twice per week), and 5/9 (55%) of them achieved the erythroid response. Conclusion. Compared with data from the literature, this prospective study revealed that EPO-zeta is a safe and effective therapeutic option in low-risk MDS patients.