Pilot Lenalidomide in Adult Diamond-Blackfan Anemia Patients w/ RBC Transfusion-Dependent Anemia

This pilot study will utilize an intra-patient dose escalation design. Cycles are 28 days in length. Subjects will receive lenalidomide 2.5 mg weekly during days 1 to 21 of cycle 1 (dose level 1). If patients do not experience any grade \> 3 hematologic or non-hematologic toxicity, the dose will be increased to 2.5 mg twice weekly on days 1 to 21 of cycle 2 (dose level 2). If patients do not experience any grade \> 3 hematologic or non-hematologic toxicity, the dose will be increased to 5 mg twice weekly on days 1 to 21 of cycle 3 (dose level 3). If patients do not experience any grade \>3 hematologic or non-hematologic toxicity, the dose will be increased to 5 mg thrice weekly on days 1 to 21 of cycle 4 (dose level 4). Patients who experience grade \>3 hematologic or non-hematologic toxicity at dose level 1 will be discontinued from study. Patients who experience grade \> 3 hematologic or non-hematologic toxicity at dose level 2, 3, or 4 will have the lenalidomide held and dose reduced according to protocol dose interruption/modification algorithms (section 5.5.3). If at least a minor erythroid response is not achieved at the end of 8 cycles of treatment, patients will be discontinued from study. If a minor or major erythroid response is achieved after completion of 8 cycles of treatment, patients can continue study drug on a maintenance phase until loss of erythroid response (return to baseline hemoglobin or transfusion requirement) or unacceptable toxicity.