Azacitidine and Lenalidomide for Acute Myeloid Leukemia

Primary: Phase 1: To determine the toxicity and feasibility of combining lenalidomide and azacitidine in patients with relapsed/ refractory AML ≥ 18 years or untreated AML ≥60 years. Phase 2: To assess the complete remission (CRm plus CRi) rate after lenalidomide + azacitidine therapy in untreated AML ≥60 years. Secondary: 1. To assess the response rate (RR), morphologic leukemia-free state, morphologic complete remission rate (CRm), cytogenetic CR (CRc) rate, CR with incomplete blood counts 14 rate, and partial remission 15 rate (PR). 2. To assess overall survival (OS) and event free survival (EFS). 3. To assess time to progression (TTP) in untreated AML ≥60 years. 4. To assess relapse free survival (RFS) and duration of CR for complete responders. 5. To determine the incidence and severity of other toxicities of lenalidomide in combination with azacitidine. 6. Assay the expression levels of cytokines/chemokines in the bone marrow plasma, expression of chemokine receptors/ligands on leukemic blasts important for the AML microenvironment and study the direct cytotoxic effects of lenalidomide, azacitidine and combination of both drugs on cryopreserved AML blast cells.