Ixazomib Citrate, Lenalidomide, Dexamethasone, and Zoledronic Acid or Zoledronic Acid Alone After Radiation Therapy in Treating Patients With Solitary Plasmacytoma of Bone

Study Summary

This randomized phase III trial compares ixazomib citrate, lenalidomide, dexamethasone and zoledronic acid with zoledronic acid alone to see how well they work when given after radiation therapy in treating patients with solitary plasmacytoma of bone. Ixazomib citrate may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. Lenalidomide may help the immune system kill abnormal blood cells or cancer cells. Dexamethasone is a drug used in chemotherapy that may cause tumor cells to die. Zoledronic acid may prevent bone fractures and reduce bone pain, and may also improve survival. Standard treatment for this cancer is radiation therapy alone. It is not yet known whether ixazomib citrate, lenalidomide, dexamethasone and zoledronic acid or zoledronic acid alone is more effective, and whether adding these treatments after radiation therapy is more effective than radiation therapy alone in treating patients with solitary plasmacytoma of bone.

Primary Outcome

Symptomatic myeloma PFS is defined as time from randomization to the first instance of criteria for multiple myeloma (MM). MM is defined as clonal bone marrow plasma cells ≥10% or biopsy-proven bony or extramedullary plasmacytoma and any one or more of the following: * Evidence of end organ damage that can be attributed to the underlying plasma cell proliferative disorder, specifically: Hypercalcaemia: serum calcium \>0.25 mmol/L (\>1 mg/dL) higher than the upper limit of normal or \>2.75 mmol/

Interventions

• DRUG dexamethasone
• DRUG lenalidomide
• DRUG zoledronic acid
• DRUG ixazomib