Ixazomib Based Maintenance Therapy for the Patients with Newly Diagnosed Multiple Myeloma in Real-World Practice

Abstract

BackgroundThe Phase III TOURMALINE-MM4 Trial demonstrated that the oral proteasome inhibitor, Ixazomib maintenance significantly improved progression-free survival (PFS) in patients with newly diagnosed multiple myeloma (NDMM) not undergoing ASCT. However, patient recruitment for clinical trials is highly selective so the extent to which study populations represent real-world patients is unclear. Currently, data validating the use of ixazomib maintenance in clinical practice in Chinese landscape is scarce.Methodswe conducted a retrospective, observational study of NDMM patients meeting International Myeloma Working Group (IMWG) criteria, who received ixazomib-based maintenance therapy. Data was collected from 26 medical centers in southern China. Enrollment was stratified by risk stage, transplant status and maintenance regimens. The characteristics, toxicities and survival outcomes were recorded.ResultsWe included 105 NDMM patients who received ixazomib-based maintenance treatment. Mean age at diagnosis was 59.82 ± 9.80 years, with 62.9% male patients. MM International Staging System (ISS), stage 3 was the most common with 49.04% of patients; 62.86% had an Eastern Cooperative Oncology Group performance score ≥2, and 81.9% with concomitant diseases. By the end of over 70 months follow-up since initial diagnosis, median PFS was 69.45 (95%CI: 31.42-107.48) months, and median OS was not achieved yet. We explored potential influencing factors of progression at the post-maintenance evaluation with a crude model using logistic regression. Difference in PFS was not statistically significant by status at pre-maintenance response, transplantation, maintenance therapy regimens (single/two/three-agent) and dexamethasone in maintenance regimens (p >0.05). Eight patients (7.62%) had grade≥3 treatment-emergent adverse events (TEAEs); 5.7% discontinued treatment because of TEAEs. Common any-grade TEAEs included fatigue (18.1%), diarrhea (16.19%), and peripheral neuropathy (11.43%).ConclusionAlthough there are certain differences in maintenance treatment options for newly diagnosed multiple myeloma patients in real-world practice, the results of our retrospective study support that the ixazomib-based maintenance therapy was effective with acceptable toxicity and single-agent ixazomib maintenance provided enough clinical benefit compared to two or three agents.Keywords: multiple myeloma, ixazomib, maintenance therapy, real-world practice [Display omitted] DisclosuresNo relevant conflicts of interest to declare.