Filanesib and Carfilzomib in Treating Patients With Relapsed or Refractory Multiple Myeloma or Plasma Cell Leukemia

PRIMARY OBJECTIVES: I. To determine the safety and the maximum-tolerated dose (MTD) of filanesib (ARRY-520) when combined with carfilzomib. SECONDARY OBJECTIVES: I. To obtain preliminary estimates of the efficacy of ARRY-520 when combined with carfilzomib. II. To explore potential markers for patient selection and obtain a preliminary assessment of the biological activity of ARRY-520 when combined with carfilzomib. OUTLINE: This is a dose-escalation study. Patients receive filanesib intravenously (IV) over 1 hour on days 1, 2, 15, and 16 and carfilzomib IV over 10-30 minutes on days 1, 2, 8, 9, 15, and 16. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity. After 8 courses of therapy, patients may continue with dosing of carfilzomib on days 1, 2, 15, and 16 and filanesib as tolerated. If patient progresses on carfilzomib maintenance with administration on days 1, 2, 15, and 16 they may increase the intensity and add in days 8 and 9 dosing. After completion of study treatment, patients are followed up within 30 days and then periodically thereafter.