Brentuximab vedotin in combination with lenalidomide and rituximab in patients with relapsed/refractory diffuse large B-cell lymphoma: Results from the phase 3 ECHELON-3 study.
Authors: Jeong A Kim, Uwe Hahn, Won-Seog Kim, Isabelle Fleury, Kamel Laribi, Juan Miguel Bergua Burgues, Krimo Bouabdallah, Nick Forward, Fontanet Bijou, David MacDonald, Craig Anthony Portell, Hervé Ghesquieres, Grzegorz S. Nowakowski, Christopher A. Yasenchak, Evelyn Rustia, Michelle Fanale, Fei Jie, Nancy L. Bartlett
Journal: Journal of Clinical Oncology (2024)

LBA7005 Background: Despite recent advances, there remains a need for novel therapies for pts with R/R DLBCL. BV, an anti-CD30 antibody-drug conjugate, has shown efficacy and safety when combined with lenalidomide (len) and with rituximab (R) in heavily pretreated populations (Bartlett 2022; Ward 2022). The double-blind, global phase 3 ECHELON-3 study (NCT04404283) compared BV with R+len (R2) vs R2 in pts with R/R DLBCL who are ineligible for HSCT or CAR T-cell therapy. Here, we present results from the interim analysis (IA) for overall survival (OS). Methods: Pts with R/R DLBCL received BV+R2 or placebo+R2 (randomized 1:1). Pts received BV (1.2 mg/kg) or placebo q3w, R (375 mg/m 2 ) q3w, and len (20 mg) qd. The primary endpoint was OS in the intent-to-treat population. Secondary endpoints were investigator-assessed progression-free survival (PFS), objective response rate (ORR), and complete response (CR) rate. The preplanned IA was performed at 134 OS events with a prespecified efficacy boundary of 2-sided P=0.0232. Results: 230 pts were randomized: 112 to BV+R2 and 118 to R2; all but 2 pts (both in R2 arm) received ≥1 dose of study drug. Median age was 71 yrs (range, 21-89), 56.5% were male, and 10.9% had an ECOG of 2. Median prior lines of therapy was 3 (range, 2-8); 29% had prior CAR T-cell therapy and 68% were CD30- (&lt;1% CD30 tumor expression). At median follow-up of 16.4 months (mos) (range, 0.1-31.5) (cut-off: January 22, 2024), median OS was 13.8 mos (95% CI: 10.3-18.8) with BV+R2 vs 8.5 mos (95% CI: 5.4-11.7) with R2 (HR 0.629; 95% CI: 0.445-0.891; P=0.0085); OS benefit was consistent across key subgroups. Median PFS was 4.2 mos (95% CI: 2.9-7.1) with BV+R2 vs 2.6 mos (95% CI: 1.4-3.1) with R2 (HR 0.527; 95% CI: 0.380-0.729; P&lt;0.0001). ORR was 64.3% (95% CI: 54.7-73.1) with BV+R2 vs 41.5% with R2 (95% CI: 32.5-51.0; P=0.0006); CR rate was 40.2% vs 18.6%, respectively. In CD30+ vs CD30- subgroups, ORR/CR was 72.2%/38.9% vs 60.5%/40.8% with BV+R2, respectively, and 50.0%/26.3% vs 37.5%/15.0% with R2, respectively. Efficacy analysis including cell of origin will be presented. The safety profile of BV+R2 was tolerable vs R2: Grade (Gr) ≥3 treatment-emergent adverse events (TEAEs) were 88% vs 77%, serious TEAEs were 60% vs 50%, and Gr 5 TEAEs were 12% vs 8%, respectively. Most common TEAEs were neutropenia (46% vs 32%), anemia (29% vs 27%), and diarrhea (31% vs 23%). Rates of peripheral neuropathy for BV+R2 vs R2 were 31% vs 24% (all Gr) and 6% vs 2% (Gr 3). Median treatment duration was 3.6 mos with BV+R2 vs 2.0 mos with R2. Conclusions: Treatment with BV+R2 triplet, compared to R2, demonstrated statistically significant and clinically meaningful improvements in all key efficacy outcomes including OS in high-risk subgroups, with manageable safety. This triplet regimen represents a novel treatment option for pts with heavily pretreated R/R DLBCL. Clinical trial information: NCT04404283 .