Pomalidomide in Combination With High Dose Dexamethasone and Oral Cyclophosphamide

Pomalidomide at 4 mg by mouth (PO) as outlined in the treatment arms.

Dexamethasone at 40 mg (20 mg) PO as outlined in the treatment arms.

"The dose escalation uses a standard 3x3 design: Ex: If none of the first 3 participants have a DLT, enter 3 participants at the next higher dose level. Once the maximum tolerated dose (MTD) of oral weekly cyclophosphamide in combination with pomalidomide and dexamethasone was determined, investigators proceeded with the second phase of the trial, a randomized phase II study comparing pomalidomide and dexamethasone with pomalidomide, dexamethasone and oral weekly cyclophosphamide delivered at the MTD determined in the phase I study."