DREAMM-7 update: Subgroup analyses from a phase 3 trial of belantamab mafodotin (belamaf) + bortezomib and dexamethasone (BVd) vs daratumumab, bortezomib, and dexamethasone (DVd) in relapsed/refractory multiple myeloma (RRMM).
Authors: Mateos Maria-Victoria , Robak Pawel , Hus Marek , Fu Chengcheng , Zherebtsova Vera , Ward Christopher , Ho P. Joy , de Almeida Ana Carolina , Hajek Roman , Kim Kihyun , Dimopoulos Meletios Athanasios , Cerchione Claudio , Pirooz Nicholas , McKeown Astrid , Kazeem Gbenga , Baig Hena , Eccersley Lydia , Roy-Ghanta Sumita , Opalinska Joanna , Hungria Vania 
Published: June 2024

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Background: Patients (pts) with RRMM and poor prognostic features, such as high-risk cytogenetics or disease refractory to major drug classes, have an unmet need. In DREAMM-7 (NCT04246047), BVd demonstrated a statistically significant and clinically meaningful progression-free survival (PFS) benefit vs standard-of-care (SOC) DVd in pts with RRMM and ≥1 prior line of treatment (LOT). We present further analyses from DREAMM-7 to better understand efficacy in key subgroups. Methods: Pts with ≥1 prior LOT were randomized (1:1) to BVd, B 2.5 mg/kg IV Q3W + V 1.3 mg/m2 (D1, 4, 8, 11 of 21-day cycles [C]; up to 8 C) and d 20 mg (D1, 2, 4, 5, 8, 9, 11, 12; up to 8 C), or DVd, D 16 mg/kg (21-day C: C1-3, Q1W; C4-8, Q3W; Q4W from C9 on)—V and d schedules were the same. The primary endpoint was independent review committee–assessed PFS. Secondary endpoints include overall survival (OS), duration of response, and overall response rate (ORR). Pts with high-risk cytogenetics had ≥1 of t(4;14), t(14;16), or del(17p13). Results: The intent to treat (ITT) included 494 pts: BVd, n=243; DVd, n=251. Median PFS (mPFS) in the ITT was 36.6 mo with BVd vs 13.4 mo with DVd (HR, 0.41; 95% CI, 0.31-0.53; P<.00001). ORR in the ITT was 82.7% (95% CI, 77.4%-87.3%) with BVd and 71.3% (65.3%-76.8%) with DVd. BVd had a higher complete response rate vs DVd (34.6% vs 17.1%). At baseline, 79 pts (33%) in the BVd arm and 87 pts (35%) in the DVd arm were refractory to lenalidomide (LEN). In the LEN-refractory subgroup, mPFS favored BVd (25.0 mo; 95% CI, 18.1 mo to NR) vs DVd (8.6 mo; 6.4-13.5 mo) (HR, 0.31; 95% CI, 0.19-0.48). A higher ORR was reported with BVd (84%; 95% CI, 73.5%-90.9%) vs DVd (61%; 49.9%-71.2%) in LEN-refractory pts. In the BVd and DVd arms, 67 (28%) and 69 (27%) pts had ≥1 high-risk cytogenetic abnormality. In the high-risk cytogenetic subgroup, the mPFS was 33.2 mo (95% CI, 20.3 mo to NR) with BVd vs 10.5 mo (7.6-13.4 mo) with DVd (HR, 0.31; 95% CI, 0.18-0.52). ORR favored BVd (85%; 95% CI, 74.3%-92.6%) vs DVd (67%; 54.3%-77.6%) in this subgroup. Additional data including other subgroup analyses will be presented. More deaths occurred with DVd (35%) than BVd (22%) in the ITT; neither arm reached median OS (HR, 0.57; 95% CI, 0.40-0.80; nominal P=.00049). In the ITT, all pts in both arms had ≥1 AE, and 95% (exposure-adjusted rate [exp-adj], 69 per 100 person-years [PY]) of BVd pts and 76% (exp-adj, 62 per 100 PY) of DVd pts reported grade 3/4 AEs. Serious AEs were reported in 50% (exp-adj, 36 per 100 PY) of BVd pts vs 37% DVd (exp-adj, 30 per 100 PY) pts. Ocular AEs were more frequent with BVd vs DVd (79% vs 29%). Conclusions: In DREAMM-7 BVd demonstrated PFS benefit over DVd with an mPFS improvement of 23 mo in pts with RRMM and ≥1 prior LOT. These results, demonstrating efficacy benefit in key subgroups with a high unmet need, support BVd as a potential new SOC in this setting. Clinical trial information: NCT04246047 .