WT1 x PRAME x cyclin A1

This phase I trial tests the safety, side effects and best dose of NEXI-001 when given with decitabine and lymphodepleting chemotherapy in treating patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) that has come back after a period of improvement (relapsed) or that has not responded to previous treatment (refractory) following an allogeneic hematopoietic cell transplantation from a matched donor. NEXI-001 is a type of chimeric antigen receptor T cell therapy in which a patient's T cells (a type of immune system cell) are changed in the laboratory so they will attack cancer cells. T cells are taken from a patient's blood. Then the gene for a special receptor that binds to a certain protein on the patient's cancer cells is added to the T cells in the laboratory. The special receptor is called a chimeric antigen receptor (CAR). Large numbers of the CAR T cells are grown in the laboratory and given to the patient by infusion for treatment of certain cancers. Decitabine is in a class of medications called hypomethylation agents. It works by helping the bone marrow produce normal blood cells and by killing abnormal cells in the bone marrow. Lymphodepleting chemotherapy, with fludarabine and cyclophosphamide, helps kill cancer cells in the body and helps prepare the body for the new CAR-T cells. Giving NEXI-001 with decitabine and lymphodepleting chemotherapy may be safe and tolerable in treating patients with relapsed or refractory AML or MDS following an allogeneic hematopoietic cell transplantation from a matched donor.