Pomalidomide, Dexamethasone, and Filgrastim-sndz in Treating Patients With Relapsed or Refractory Multiple Myeloma

PRIMARY OBJECTIVES: I. To determine the maximum tolerated dose (MTD) of pomalidomide and dexamethasone when given with growth factor support in patients with relapsed and refractory multiple myeloma. (Phase I) II. To evaluate the safety of pomalidomide and dexamethasone at the MTD. (Phase II) SECONDARY OBJECTIVES: I. To obtain preliminary estimates of the anti-myeloma activity of higher doses of pomalidomide given with low dose dexamethasone and growth factor support in patients with relapsed and refractory multiple myeloma. II. Activity will be defined by the overall response rate (ORR); (partial response \[PR\] or better) and clinical benefit response (CBR) rate (minor response \[MR\] or better), as well as by the response durability (duration of response \[DOR\], progression-free survival \[PFS\], and time to progression \[TTP\]). III. To further evaluate the safety of pomalidomide and dexamethasone at the maximum tolerated dose (MTD). EXPLORATORY OBJECTIVES: I. To examine the influence of cereblon expression and activation of the wingless-type (Wnt)/beta-catenin pathway on the activity of high dose pomalidomide with low dose dexamethasone. OUTLINE: This is a phase I, dose-escalation study of pomalidomide followed by a phase II study. INDUCTION: Patients receive pomalidomide orally (PO) daily on days 1-21, dexamethasone PO on days 1, 8, 15, and 22, and filgrastim-sndz subcutaneously (SC) on days 22-28. Treatment repeats every 28 days for 6 courses in the absence of disease progression or unacceptable toxicity. MAINTENANCE: Patients receive lower-dose pomalidomide PO daily on days 1-21 and dexamethasone PO on days 1, 8, 15, and 22. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 3 months for 1 year and then every 6 months thereafter.