Chidamide Monotherapy for Intermediate-to-High-Risk Myelodysplastic Syndromes

This is a prospective, open-label, single-arm phase II study designed to evaluate the efficacy and safety of chidamide monotherapy in participants with intermediate-to-high-risk myelodysplastic syndromes (MDS) who have limited therapeutic options or are not suitable for intensive chemotherapy or hypomethylating agent therapy. Eligible participants will receive oral chidamide at an initial dose of 20 mg twice weekly. Each dose consists of four 5-mg tablets taken approximately 30 minutes after meals. Treatment may continue for up to 3 months, with a planned follow-up period of 6 months. The primary objective is to evaluate the overall response rate (ORR) after chidamide treatment. Treatment response will be assessed according to hematologic response and bone marrow evaluation as specified in the study protocol. Secondary objectives include assessment of safety, tolerability, dose modification, treatment discontinuation, and changes in blood cell counts. Participants will be followed for treatment response, adverse events, laboratory abnormalities, and overall clinical status for up to 6 months after initiation of study treatment.