Ixazomib dexamethasone a new treatment in the arsenal against RRMM

In heavily pretreated, lenalidomide-refractory patients with relapsed-refractory multiple myeloma (RRMM) and prior exposure to proteasome inhibitors (PI), ixazomib dexamethasone (ixa-dex) may be an effective and tolerable treatment approach, leading to comparable health-related quality of life (HRQoL) outcomes as pomalidomide-dexamethasone (pom-dex), a recent study has found.

The present phase II trial randomized 122 RRMM patients 3:2 to receive either ixa-dex (n=73) or pom-dex (n=49) until progression or toxicity. All participants were refractory to lenalidomide, had prior exposure or were intolerant to carfilzomib or bortezomib, and had had ≥2 prior lines of therapy. Outcomes were treatment response, safety, and HRQoL.

There were 46 (63 percent) and 34 (69 percent) progression events in the ixa-dex and pom-dex arms, respectively, with corresponding median progression-free survival (PFS) times of 7.1 and 4.8 months, suggesting no significant difference between arms (hazard ratio [HR], 0.847, 95 percent confidence interval [CI], 0.535–1.341; p=0.477).

Stratifying patients according to the number of prior lines of therapy (2 and ≥3) did not meaningfully alter the principal findings, and median PFS remained comparable between ixa-dex and pom-dex arms. Similarly, HRQoL outcomes in ixa-dex were comparable to those in pom-dex.

In terms of safety, the researchers reported grade ≥3 treatment-emergent adverse events (TEAEs) in 69 percent and 81 percent of ixa-dex and pom-dex patients, respectively. Corresponding rates for serious TEAEs were 51 percent and 53 percent, and 39 percent and 36 percent for TEAEs leading to drug discontinuation. Both arms had a 13-percent death rate.

“RRMM is a heterogeneous disease, and no single treatment benefits all patients. Ixa-dex is an appropriate option for patients who cannot tolerate triplet combinations, or who are not able or prefer not to receive parenteral treatment administration, or who require a non-immunomodulatory drug-based treatment approach,” the researchers said.