The addition of elotuzumab to lenalidomide and dexamethasone significantly improved survival outcomes in patients with relapsed/refractory multiple myeloma (MM), according to a study published in Blood Cancer Journal.
The open-label, multicenter, randomized, phase III ELOQUENT-2 study included 646 patients with relapsed/refractory MM who had received one to three prior lines of therapy. Patients were randomized 1:1 to receive lenalidomide and dexamethasone alone (n=325) or in combination with elotuzumab (n=321).
After a minimum follow-up of 70.6 months, the addition of elotuzumab statistically significantly improved overall survival (OS) by 8.7 months (median, 48.3 months with elotuzumab vs. 39.6 months with lenalidomide and dexamethasone alone; hazard ratio, 0.82; 95.4% confidence interval [CI], 0.68-1.00; P=0.0408), representing an 18% reduced risk of death with the addition of elotuzumab. This outcome was consistent across key predefined subgroups, including those with high-risk disease, del(17p) mutations in one or more cells, prior hematopoietic cell transplantation, or International Staging System stage III disease.
Median duration of response was 21.9 months in the elotuzumab cohort (95% CI, 18.4-26.6) and 17.1 months in the lenalidomide and dexamethasone alone cohort (95% CI, 15.2-19.4).
No additional safety concerns were reported with elotuzumab at extended follow-up. Fewer deaths occurred in the elotuzumab cohort (67% vs. 71%). In the elotuzumab combination and lenalidomide and dexamethasone alone cohorts, the most common all-cause any-grade adverse events (AEs) were diarrhea (50% vs. 39%), fatigue (49% vs. 41%), anemia (44% vs. 38%), pyrexia (41% vs. 26%), constipation (36% vs. 28%), and neutropenia (36% vs.43%). All-cause grade 3/4 AEs occurred in 77% and 68% of patients, respectively.
“[Elotuzumab plus lenalidomide and dexamethasone] is the first antibody-based triplet regimen shown to significantly prolong OS in patients with relapsed/refractory MM [who received] one to three prior lines of therapy,” the authors concluded.