Aptose Biosciences Inc. is a clinical-stage biotechnology company. The company is advancing therapeutics to treat life-threatening cancers, such as acute myeloid leukemia, high-risk myelodysplastic syndromes and other hematologic malignancies. Its lead program APTO-253 has completed a Phase 1 study in patients with solid tumors. Aptose Biosciences Inc., formerly known as Lorus Therapeutics Inc., is headquartered in Toronto, Canada.