- PFS improved 39% in patients with multiple myeloma (MM) taking ixazomib vs placebo after autologous stem cell transplantation (ASCT).
Why this matters
- 29% of patients discontinue lenalidomide, the only approved maintenance therapy for MM after ASCT, for treatment-related adverse events (AEs).
- Phase 3, double-blind, placebo-controlled TOURMALINE-MM3 trial randomly assigned 656 patients with MM to receive 3-4 mg oral proteasome inhibitor (PI) ixazomib (n=395) or placebo (n=261) after ASCT on days 1, 8, and 15 of 28-day cycles.
- Therapy for 2 years or until progressive disease/intolerable toxicity.
- Funding: Takeda.
- At median 31 months follow-up, median PFS was significantly longer with ixazomib vs placebo (26.5 vs 21.3 months; HR, 0.72; 95% CI, 0.58-0.89; P=.002).
- 54% of patients showed disease progression.
- PFS significantly improved by 39% with ixazomib.
- Observed across stage III, high-risk cytogenetics, PI-exposed, and PI-naive subgroups.
- Deepened response rates with ixazomib vs placebo (relative risk, 1.41; 95% CI, 1.10-1.80; P=.004).
- 12% ixazomib vs 7% placebo patients converted from minimal residual disease positivity to negativity.
- AE discontinuation in 7% ixazomib vs 5% placebo.
- Grade ≥3 AEs in 42% ixazomib vs 26% placebo, primarily infections, gastrointestinal. disorders, neutropenia, and thrombocytopenia.
- Serious AEs in 27% ixazomib vs 20% placebo.
- New primary malignancy 3% in both groups.