- Ixazomib maintenance therapy extends PFS by 39% in patients with multiple myeloma (MM) after autologous stem cell transplantation (ASCT).
Why this matters
- Lenalidomide is commonly used post-ASCT as maintenance therapy, but nearly one-third of patients discontinue it because of toxicity.
- Phase 3 multicenter TOURMALINE-MM3 trial of 656 adults with newly diagnosed MM with at least a partial response (PR) to induction therapy (proteasome inhibitor or immunomodulatory agent) before ASCT.
- Randomly assigned 3:1 to weekly ixazomib or matched placebo.
- 3 mg ixazomib was administered on days 1, 8, and 15 of 28-day cycles for 2 years or until disease progression/unacceptable toxicity, up to 26 cycles.
- For patients tolerating ixazomib 3 mg during the first 4 cycles, dose was increased to 4 mg.
- Median patient age, 58 years (>65 years, 15%).
- Median follow-up, 31 months.
- Funding: Takeda.
- Median PFS was longer with ixazomib (26.5 vs 21.3 months; HR, 0.72; P=.002), representing a 39% improvement.
- Ixazomib yielded a higher rate of conversion from minimum residual disease (MRD)-positive to MRD-negative status (12% vs 7%).
- Grade ≥3 adverse events were higher with ixazomib (42% vs 26%).
- Median OS not reached in either group.
- Low rate of second primary malignancies (3%) in both groups.
- OS data not mature.