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