|The following article features coverage from the European Hematology Association 2020 virtual meeting. Click here to read more of Cancer Therapy Advisor‘s conference coverage.|
Maintenance therapy with ixazomib postinduction prolonged progression-free survival (PFS) compared with placebo among patients with newly diagnosed multiple myeloma (MM) who were not eligible for transplant, according to results from the phase 3 TOURMALINE-MM4 trial presented at the Virtual Edition of the 25th European Hematology Association (EHA) Annual Congress.
Maintenance therapy can delay disease progression among newly diagnosed patients with MM not undergoing transplant, but there are no specific agents approved in this space.
“A number of agents have been investigated, but proteosome inhibitor–based maintenance has not been studied in a placebo-controlled trial,” Meletios A. Dimopoulos, MD, of the National and Kapodistrian University of Athens in Greece, and lead author and presenter, said.
The international, multicenter, double-blind phase 3 TOURMALINE-MM4 trial randomly assigned 706 patients with newly diagnosed MM ineligible for or who did not want to undergo transplant 3:2 to receive maintenance postinduction therapy with ixazomib (425 patients) or placebo (281 patients) for up to 2 years. Patients had to achieve at least a partial response (PR) during induction therapy. The primary endpoint was PFS and the key secondary endpoint was overall survival (OS).
At baseline, the median age was 73, ISS stage III disease was present in 35% of patients, and 17% had high risk cytogenetics. The use of an immunomodulatory drug during induction was similar between arms at 33%.
PFS was significantly longer in the ixazomib arm, with a median of 17.4 months compared with 9.4 months with placebo (hazard ratio [HR], 0.66; 95% CI, 0.54-0.80; P <.001) during a median follow-up of 21.1 months. The 24-month PFS was 39.2% with ixazomib compared with 24.1% with placebo.
The PFS benefit was observed across all subgroups, including preinduction ISS stage, age, prior proteosome inhibitor exposure, prior immunomodulator drug (IMiD) exposure, and frailty.
Overall survival data are not yet mature.
A majority of patients experienced grade 1 to grade 2 treatment-emergent adverse events (TEAEs). Discontinuation due to TEAEs occurred in 13% of patients in the ixazomib arm and 8% of patients in the placebo arm. Common TEAEs that occurred more frequently with ixazomib compared with placebo included nausea, vomiting, and diarrhea.
In conclusion, Dr Dimopoulos said that ixazomib “may provide a valuable maintenance option in combination with other agents such as IMiDs and mAbs.”
Read more of Cancer Therapy Advisor‘s coverage of the EHA virtual meeting by visiting the conference page.
Dimopoulos MA, Špička I, Quach H, et al. Ixazomib vs placebo as post-induction maintenance therapy in newly diagnosed multiple myeloma (NDMM) patients (pts) Not undergoing autologous stem cell transplant (ASCT): Phase 3 TOURMALINE-MM4 trial. Paper Presented at: Virtual Edition of the 25th European Hematology Association (EHA) Annual Congress; June 2020. Abstract S200.