Phase 1/2 trial of ixazomib, cyclophosphamide, and dexamethasone for newly diagnosed multiple myeloma (NDMM).

8002Background: Ixazomib (Ixa) is an oral proteasome inhibitor, approved for treatment of relapsed myeloma (MM) in combination with lenalidomide and dexamethasone (Dex). The combination of bortezomib with cyclophosphamide (Ctx) and Dex is an effective regimen for initial therapy of MM. The combination of Ixa, Ctx and Dex could provide an effective, all oral regimen for initial therapy of MM. Methods: NDMM patients (pts) with measurable disease, adequate organ function, and an ECOG PS >=2 were enrolled. The primary objective of the phase 1 was to determine the MTD of Ctx that can be combined with Ixa and Dex. Pts received Ixa 4 mg on days 1, 8, 15, dex 40 mg days 1, 8, 15, 22 and cyclophosphamide 300 or 400 mg/m2 days 1, 8, 15, 22; cycles were 28 days. Patients could continue on ixa alone after 12 cycles. The phase 2 portion was designed to determine the complete plus very good partial response rate (>=VGPR) of ixazomib to be used in combination with cyclophosphamide and dexamethasone in ND MM. Results: Fi...