A Study Being Conducted at Multiple Locations to Compare Safety and Efficacy of Three Different Regimens; (1) High-Dose Lenalidomide; (2) Lenalidomide + Azacitidine; or (3) Azacitidine in Subjects ≥ 65 Years With Newly-Diagnosed Acute Myeloid Leukemia

Inclusion Criteria:

* Newly diagnosed acute myeloid leukemia (AML), AML with antecedent hematologic disorder or therapy-related AML
* Male or female subjects aged ≥ 65
* Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1 or 2
* White blood cell (WBC) count ≤ 10 x 10⁹/L at screening

Exclusion Criteria:

* Previous treatment with azacitidine, decitabine, cytarabine or lenalidomide
* Previous cytotoxic or biologic treatment of any kind for AML or prior use of targeted therapy agents.
* Suspected or proven acute promyelocytic leukemia
* Prior bone marrow or stem cell transplantation
* Candidate for allogeneic bone marrow or stem cell transplantation
* AML antecedent hematologic disorder such as chronic myelogenous leukemia or myeloproliferative neoplasms
* Presence of malignant disease within the previous 12 months with exceptions