Aptose Biosciences Inc., a clinical-stage biotechnology company, discovers and develops personalized therapies addressing unmet medical needs in oncology primarily in the United States. Its clinical programs include APTO-253, which is in Phase 1a/b clinical trial for the treatment of patients with relapsed or refractory blood cancers, including acute myeloid leukemia (AML) and high-risk myelodysplastic syndrome (HR MDS); and HM43239 that is in Phase 1/2 clinical trial to treat patients with relapsed or refractory AML. The company also develops luxeptinib, which is in Phase 1a/b clinical trial for treating patients with relapsed or refractory B-cell malignancies, including chronic lymphocytic leukemia, small lymphocytic lymphoma, and various non-Hodgkin's lymphomas, as well as AML and HR MDS; and APL-581, a dual bromodomain and extra-terminal domain motif protein and kinase inhibitor program. It has agreements with CrystalGenomics, Inc. and OHM Oncology. The company was formerly known as Lorus Therapeutics Inc. and changed its name to Aptose Biosciences Inc. in August 2014. Aptose Biosciences Inc. was incorporated in 1986 and is headquartered in Toronto, Canada.