Abstract / Summary
Background: Multiple myeloma (MM) is an incurable hematologic malignancy, requiring sustained therapeutic management to mitigate disease recurrence. Ixazomib, a first-generation oral proteasome inhibitor, has exhibited substantial clinical efficacy and is widely employed in clinical practice. According to prescribing guidelines, ixazomib is typically administered at an initial dose of 4 mg weekly for 3 weeks, with dose reduction to 3 mg weekly in the event of adverse effects. Prior exposure-response analyses have confirmed that both 3 and 4 mg doses reside within the clinically effective range. This study aims to assess the comparative efficacy and toxicity profiles of 3 versus 4 mg ixazomib in MM.
Methods: We performed a retrospective analysis of 207 MM patients undergoing ixazomib-based therapy across six medical centers. Patients were stratified into three subgroups: initial treatment, in-class transition, and maintenance/continuation therapy group. Additionally, patients were categorized into two cohorts according to ixazomib dosage: 3 or 4 mg. Demographic characteristics, baseline clinical features, and therapeutic outcomes were compared between the 3 and 4 mg cohorts.
Results: Our results indicate that 3 and 4 mg ixazomib demonstrate equivalent efficacy in induction, class-switch, and maintenance/continuation therapy across most clinical scenarios in Chinese MM patients. Subgroup analysis within the in-class transition cohort revealed that patients with RISS Stage 3 disease exhibited prolonged progression-free survival in the 4 mg group. Furthermore, patients with an ECOG performance status of one to two achieved enhanced overall survival with the 4 mg dose. The overall adverse event rates were comparable between the two dose groups. Notably, during the induction phase, the 4 mg group exhibited a significantly higher incidence of Grades 1-2 vomiting (p = 0.016).
Conclusions: These findings suggest that initiating therapy with 3 mg ixazomib is both clinically viable and effective, potentially alleviating the economic burden for MM patients.