Aim: To compare the effectiveness of in-class transition to all-oral ixazomib-lenalidomide-dexamethasone (IRd) following parenteral bortezomib (V)-based induction versus continued V-based therapy in US oncology clinics. Patients & methods: Non-transplant eligible patients with newly diagnosed multiple myeloma (MM) receiving in-class transition to IRd (N = 100; US MM-6), or V-based therapy (N = 111; INSIGHT MM). Results: Following inverse probability of treatment weighting, overall response rate was 73.2% with IRd versus 57.5% with V-based therapy (p < 0.0001). Median duration of treatment was 10.8 versus 5.3 months (p < 0.0001). Overall, 18/24% of patients discontinued IRd/V-based therapy due to adverse events. Conclusion: IRd after V-based induction was associated with significantly improved overall response rate and duration of treatment than continued V-based combination therapy. Clinical Trial Registration: US MM-6: NCT03173092; INSIGHT MM: NCT02761187 (ClinicalTrials.gov).
Keywords: In-class transition; Ixazomib; oral therapy; proteasome inhibitor.