Clinical trials

The goal of this clinical trial is to learn about the safety and effectiveness of the combination drug Tetrahydrouridine (THU) and decitabine (DEC) to treat patients with relapsed or refractory myelodysplastic syndrome. The main questions it aims to answer are: * Does the combination drug exhibit hematological and nonhematological toxicity? * Does the combination drug improve health status and reduce the number of days of hospitalization? Participants will: * Take tetrahydrouridine and decitabine once a week for 24 weeks * Visit the clinic once every 4 weeks for checkups and tests * Keep a diary of their symptoms