This article was originally published here
Cancer Med. October 16, 2021. doi: 10.1002 / cam4.4313. Online ahead of print.
BACKGROUND: Maintenance treatment with proteasome inhibitors (PIs) may improve outcomes in patients with multiple myeloma (MM), however, the neurotoxicity and parenteral route of bortezomib limits its long-term use. An efficient, tolerable and practical PI option is needed.
METHODS: In this real-world, single-center study, we retrospectively analyzed the outcome and safety profile of ixazomib maintenance therapy in patients who reached a plateau with stable disease responses or better after bortezomib-based induction therapy in patients with MM not undergoing transplantation.
RESULTS: Of the 71 patients, 37 cases (52.1%) were newly diagnosed MM (NDMM) and 34 cases (47.9%) were relapsed and / or refractory MM (RRMM). The overall response rate (ORR) was 81.7%, including 34 patients (47.9%) with a very good or better response rate (≥VGPR) after a median of nine cycles (6-14) of treatment induction based on bortezomib. Then, the ORR was transformed to 74.6% including 39 patients of ≥VGPR (54.9%) after a median of six courses (2-25) of maintenance treatment with ixazomib. Of these, 18 patients (25.4%) exhibited in-depth responses. With a median follow-up of 26.5 months, the median progression-free survival (PFS) was 28.4 and 16.5 months from the start of bortezomib and 16.2 and 10.0 months from the start of ixazomib in the NDMM and RRMM groups, respectively. Additionally, responses deepened during the maintenance phase (hazard ratio: 0.270, p = 0.007) and ≥VGPR responses during the induction phase (hazard ratio: 0.218, p
CONCLUSION: This real-world analysis demonstrated that oral ixazomib is a favorable long-term administration option for maintenance with efficacy and feasibility and confirmed the association between deepening of responses with ixazomib and prolonged PFS.