ABSTRACT
Objective:To explore the efficacy and safety of in-class transition from proteasome inhibitor bortezomib to ixazomib in the treatment of newly-treated patients with multiple myeloma (MM).Methods:The clinical data of 63 newly-treated MM patients in Shenzhen Second People's Hospital from January 2018 to December 2020 were retrospectively analyzed. They were divided into transition group (23 cases) and bortezomib group (40 cases). Both groups were treated with bortezomib-containing regimen as the first-line treatment regimen. In case of intolerable adverse reactions, patients in the transition group were treated with ixazomib instead of bortezomib, while the patients in the bortezomib group did not undergo drug transition. The curative effect and progression-free survival (PFS) were compared between the two groups.Results:In the transition group, the overall response rate (ORR) before in-class transition was 95.7% (22/23), the rate of ≥ very good partial remission (VGPR) was 52.2% (12/23); the ORR after transition was 95.7% (22/23), and the rate of ≥ VGPR was 82.6% (19/23). In the bortezomib group, ORR was 90.0% (36/40), and the rate of ≥ VGPR was 72.5% (29/40). There was no significant difference in ORR and the rate of ≥VGPR between the two groups ( χ2 = 0.64, P=0.424; χ2 = 0.82, P = 0.364). The median number of cycles of PI therapy in the transition group was 9, and the median PFS time was not reached. The median number of cycles of PI therapy in the bortezomib group was 7.5, and the median PFS time was 30.0 months (95% CI 19.1-40.9 months), there was no significant difference in PFS between the two groups ( P = 0.275). In the bortezomib group, 12 patients discontinued bortezomib due to adverse reactions, the median PFS time was 20.0 months (95% CI 12.6-27.4 months), and the PFS of patients who discontinued PI in the transition group and the bortezomib group was compared, the difference was statistically significant ( P = 0.043). In the transition group, 21 patients (21/23, 91.3%) developed peripheral neuropathy, and the incidence of ≥grade 3 adverse reactions was 13.0% (3/23); in the bortezomib group, 22 patients (22/40, 55.0%) developed peripheral neuropathy, and the incidence of ≥grade 3 adverse reactions was 12.5% (5/40). Conclusions:For newly-treated MM patients, the transition from bortezomib to ixazomib can improve the depth of remission and reduce the recurrence caused by the discontinuation of PI.