This study is testing a new drug called **BMF-219**, which is a *menin inhibitor*. Menin is a protein that can affect cancer growth. This study is for adults with certain types of blood cancers, like acute myeloid leukemia (**AML**) and diffuse large b-cell lymphoma (**DLBCL**). The study is in Phase 1, meaning it's the first time humans are trying this medicine to find the best dose and see if it works. To participate, you must be at least 18 years old, have certain types of cancer, and have tried other treatments that didn't work. You should also be in good health overall. Some people can't join, like those with certain other health problems or those who have tried similar drugs before. **Key Points:** - You must visit the study site several times for check-ups and medication. - You must use birth control during the study and for 90 days after. - The study is a chance to try a new treatment, but there might be risks since it's still being tested. If you meet these requirements, this study could be an option for you.