In an analysis of real-world data, the all-oral triplet regimen of ixazomib, lenalidomide, and dexamethasone (IRD) for the treatment of multiple myeloma (MM) was beneficial and well-tolerated.
A team of researchers from the Czech Republic sought to confirm findings from the TOURMALINE-MM1 clinical trial, which evaluated the efficacy of adding oral ixazomib to the combination of lenalidomide and dexamethasone (RD). To assess this, they performed a head-to-head comparison of the all-oral IRD versus RD regimens in patients with relapsed/refractory (RR) MM in routine clinical practice.
In total, 344 patients with RRMM were enrolled, of whom 127 were treated with IRD and 217 were treated with RD. The primary study endpoint was progression free survival (PFS), and secondary endpoints included overall response rates (ORR) and overall survival (OS).
Overall, the IRD cohort achieved a median PFS of 17.5 months compared with 11.5 months for the RD group (P=0.005). For patients within their first to third relapse, median PFS was 23.1 versus 11.6 months for the IRD and RD cohorts, respectively. The calculated hazard ratio for PFS was 0.67 (95% confidence interval [CI], 0.51-0.89; P=0.006). Patients who received the triplet regimen also achieved improved OS, or a median of 36.6 months versus 26.0 months for the RD cohort (P=0.008). The ORR was 73.0% for patients who received IRD, with 11.1% achieving a complete response (CR). The ORR was 66.2% for those who received RD, with a CR rate of 8.8%. A very-good partial response was achieved in 22.2% and 13.9% of the IRD and RD groups, respectively.
Both regimens were well-tolerated, with similar incidence of adverse events and toxicity. The triplet regimen was found to be most beneficial in patients aged 75 years or younger, with stage I or II disease, and in their first or second relapse.
“The present analysis shows that for patients with RRMM treated in routine clinical practice, IRD is well-tolerated and was associated with better PFS and OS when compared to RD,” the researchers concluded.
This study was published in BMC Cancer.