Belantamab mafodotin, pomalidomide, and dexamethasone in Japanese patients with RRMM in the phase 3 DREAMM-8 trial

The phase 3 DREAMM-8 (NCT04484623) trial assessed belantamab mafodotin + pomalidomide + dexamethasone (BPd) vs bortezomib + Pd (PVd) in lenalidomide-exposed patients with relapsed/refractory multiple myeloma (RRMM) and ≥ 1 prior therapy. Here, we present findings from Japanese patients (data cutoff: 27-May-24). The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall response rate (ORR), duration of response (DoR), and safety. Overall, 21 patients were randomized 1:1 to BPd (N = 10) and PVd (N = 11). Median follow-up was 13.8 months (range 0.23-26.71). For BPd vs PVd, median PFS was not reached (NR; 95% CI 0.2-NR) vs 14.8 months (95% CI 1.9-NR; HR 0.53; 95% CI 0.1-2.8); ORR was 90% (9/10) vs 73% (8/11), including very good partial response or better in 70% (7/10) vs 36% (4/11); median DoR was NR vs 17.5 months. The safety profile was consistent with the global cohort. Ocular adverse events were more common with BPd vs PVd (90% [9/10] vs 9% [1/11]) and a majority were transient and reversible. While the sample size of this study is small, findings were aligned with the global cohort. BPd showed favorable efficacy compared with PVd, with a manageable safety profile in lenalidomide-exposed Japanese patients with RRMM.