This study is looking at IO-202 as a potential new cancer treatment for acute myeloid leukemia (AML) or chronic myelomonocytic leukemia (CMML) when given alone and in combination with azacitidine.

IO-202 is an antibody, which is a protein that is part of the immune system that attaches to specific targets. The IO-202 antibody targets leukemia cells that carry a leukemia-associated protein. IO-202 is not approved by the U.S. Food and Drug Administration (FDA).It is currently being used for research purposes only.

Azacitidine is a chemotherapy drug that works by helping the bone marrow grow normal blood cells. Azacitidine also kills abnormal blood cells that do not work properly. Azacitidine is approved by the FDA for the treatment of several types of blood cancers, including AML and CMML. It is considered investigational to give IO-102 with azacitidine.

This study has two treatment groups. Group 1 will receive IO-202 alone while Group 2 will receive both IO-202 and azacitidine. The IO-202 dose level participants will receive and whether they’ll receive azacitidine will depend on the dosing group that is open at the time of enrollment. The study doctor will inform participants which treatment arm is available.

IO-202 will be administered intravenously (through an IV) and azacitidine will be administered either through an IV or through an injection in the arm.

Participants can stay on the study as long as they are doing well, and their leukemia has not gotten worse. After stopping the study drug, participants will return to the clinic 30 days later to see how well they are doing.