This study is testing a new medicine called emavusertib for adults with certain blood cancers, Acute Myelogenous Leukemia (AML) or Myelodysplastic Syndrome (MDS). AML is a cancer where the bone marrow makes abnormal blood cells, while MDS affects how blood cells develop. The study has two main parts. In the first part, the study checks how much of the medicine is safe to take. The second part looks at how well the medicine works. Patients take emavusertib in pill form twice a day, and each cycle lasts 28 days. They can continue as long as they don't have bad side effects and the medicine helps. To join, patients must be at least 18 years old and have tried other treatments first. They cannot have certain other conditions, be pregnant, or breastfeeding.

• The study tests safety and effectiveness of emavusertib in patients with specific mutations.
• Participants must have tried 1 or 2 prior treatments and be able to swallow pills.
• Patients are monitored for side effects and can leave the study if they wish.