Lenalidomide, Thalidomide and Dexamethasone in Treating Participants With Relapsed or Refractory Multiple Myeloma

PRIMARY OBJECTIVES: I. To determine the maximum tolerated dose (MTD) of the combination of lenalidomide and thalidomide and dexamethasone (LTD) in patients with relapsed/refractory multiple myeloma (RRMM). (Phase 1) II. To determine the overall (complete remission \[CR)\]+ very good partial response \[VGPR\]+ partial response \[PR)\] response rate of the combination after 4 cycles of therapy. (Phase 2) SECONDARY OBJECTIVES: I. To determine the overall response rate (ORR). (Phase 1) II. To determine the time to progression (TTP). (Phase 1) III. To determine the progression free survival (PFS). (Phase 1) IV. To determine the time to best response. (Phase 1) V. To determine the CR, VGPR. (Phase 2) VI. To determine the time to progression (TTP). (Phase 2) VII. To determine the progression free survival (PFS). (Phase 2) VIII. To determine the time to best response. (Phase 2) IX. To assess the safety of the combination of LTD in patients with RRMM. (Phase 2) X. Time to next therapy. (Phase 2) XI. Symptom measurement - multiple-symptom assessment tool. (Phase 2) OUTLINE: This is a dose-escalation study of lenalidomide and thalidomide. Participants receive lenalidomide orally (PO) on days 1-21 and thalidomide PO once daily (QD) on days 1-28. Participants also receive dexamethasone PO QD on days 1-4, 9-12, and 17-20 of courses 1-2, and days 1, 8, 15, and 22 of subsequent courses. Treatment repeats every 28 days for up to 8 courses in the absence of disease progression or unacceptable toxicity. MAINTENANCE THERAPY: Participants who have stable or responding disease to treatment receive lenalidomide PO on days 1-21 and thalidomide PO QD on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. Participants may receive dexamethasone at the discretion of the investigator. After completion of study treatment, patients are followed up at 30 days.