A drug used with other drugs to treat acute myeloid leukemia that is newly diagnosed. It is used in adults who are 75 years and older or in adults who cannot be treated with other anticancer drugs. Venetoclax is also used to treat chronic lymphocytic leukemia and small lymphocytic lymphoma in adults. It is also being studied in the treatment of other types of cancer. Venetoclax binds to a protein called BCL2, which is found on some types of cancer cells. Blocking this protein may help kill cancer cells and may make them more sensitive to anticancer drugs. Venetoclax is a type of BCL2 inhibitor. Also called Venclexta.