These are 2 parts to this study. The purpose of the first part is to test the safety of IRX5183 at different dose levels. The investigators want to find out what effects, good and/or bad, it has on AML or MDS. Once the investigators figure out the best and safest dose of IRX5183, the investigators will enter the second part of the study using this dose. The purpose of the second part is to see if IRX5183 is effective as a treatment for AML or MDS. To date, IRX5183 has been used in about 25 people.