Acute myeloid leukemia (AML) is a cancer derived from myeloid progenitor or stem cells that typically mature into red blood cells, white blood cells or platelets. AML initiates in the bone marrow when stem or progenitor cells lose cell cycle control, anti-apoptotic factor or other means to limit rampant proliferations. Leukemic cells have the ability to rapidly spread from the marrow to the bloodstream. Further, these rapidly proliferating cells quickly crowd out normal cells as they infiltrate other organs and tissue systems.
The Leukemia & Lymphoma Society estimates prevalence for AML of 35,726 as of January 1, 2010, and the American Cancer Society projects new AML diagnoses of 18,860 patients and deaths of 10,460 in 2014. Elderly patients are disproportionately impacted by AML, at rates four times more prevalent in patients over 60 years of age, with an incidence rate of 1 / 1020, whereas individuals under age 60 years have an incidence rate of approximately 1 / 4500.
The current standard of care in patients with AML is chemotherapy with cytarabine, infused over seven days continuously, and daunorubicin, infused over three days, hence known as the “7+3” regimen. The therapy is known to have significant side effects and, as a result, many patients are deemed to be ineligible. A recent survey of key opinion leaders by Datamonitor reported that of patients over the age of 60, only 28 percent are placed on an induction chemotherapy regimen, while 51 percent are enrolled in a clinical trial and 21 percent are provided best supportive care only. The lack of a tolerable regimen for a significant proportion of patients with AML constitutes the immense need for new therapies.