For patients with relapsed/refractory multiple myeloma, carfilzomib is superior to bortezomib for progression-free survival, regardless of previous treatments or prior exposure to either bortezomib or lenalidomide, a subgroup analysis of the ENDEAVOR trial published in Leukemia has shown.1

For this multicenter, open-label, pivotal, phase 3 trial, researchers randomly assigned 929 patients with relapsed/refractory multiple myeloma to receive carfilzomib plus low-dose dexamethasone, or bortezomib plus low-dose dexamethasone. Participants received treatment until disease progression. After a median follow-up of 11.9 months in the carfilzomib group and 11.1 months in the bortezomib group, median progression-free survival was 18.7 months and 9.4 months, respectively (hazard ratio, 0.53; 95% CI, 0.44-0.65; P < .0001).

Investigators conducted a subgroup analysis of data from patients, categorized either by the number of previous therapies or by prior treatment. For patients with 1 prior therapy, median progression-free survival was 22.2 months with carfilzomib, versus 10.1 months with bortezomib. For patients who received 2 or more prior lines, median progression-free survival was 14.9 months and 8.4 months, respectively.

Among patients previously treated with bortezomib, median progression-free survival was 15.6 months for carfilzomib, in contrast with 8.1 months with bortezomib; for those previously treated with lenalidomide, median progression-free survival was 12.9 months versus 7.3 months, respectively.

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Overall response rates were 81.9% versus 65.5% after 1 prior line, 72.0% versus 59.7% after 2 or more prior lines, 71.2% versus 60.3% with prior bortezomib, and 70.1% versus 59.3% with prior lenalidomide for carfilzomib and bortezomib, respectively.

Toxicity profiles associated with carfilzomib-dexamethasone and bortezomib-dexamethasone in each subgroup were similar to those of the overall study population.

Reference

1. Moreau P, Joshua D, Chng W-J, et al. Impact of prior treatment on patients with relapsed multiple myeloma treated with carfilzomib and dexamethasone vs bortezomib and dexamethasone in the phase 3 ENDEAVOR study. Leukemia. In press.