The purpose of the study is to evaluate the potential interaction between ASTX727 and venetoclax, the study drugs, evaluate the safety when the study drugs are taken together, and any potential benefits of taking the study drugs together.

The study is expected to last about 20 months. The amount of time you will be on study treatment or be followed up for health information as part of the study depends on how you respond to and tolerate the study treatment. Study assessments/procedures will occur during screening, a period in which your eligibility to enter the study is determined, while on treatment, at treatment discontinuation, when you decide to or are taken off the study treatment, and during the safety follow-up period. While in the study you must follow the directions given to you by the study staff. If you do not follow the directions given to you, you may not be able to continue taking part in the study. You must come to the study center for all visits, including the follow-up visit after your last dose of study treatment, unless you are told a telephone call is an acceptable option.