Efficacy and safety of daratumumab, bortezomib, and dexamethasone (D-Vd) in relapsed or refractory multiple myeloma (RRMM) based on cytogenetic risk: Updated subgroup analysis of CASTOR.

8040 Background: MM patients (pts) with high cytogenetic risk have poor outcomes. In CASTOR, D-Vd prolonged progression-free survival (PFS) vs bortezomib and dexamethasone (Vd) alone, and exhibited tolerability in RRMM pts. We conducted a subgroup analysis of D-Vd vs Vd in CASTOR, based on cytogenetic risk. Methods: Pts received ≥1 prior line of therapy. Cytogenetic risk was based on a combined analysis of next-generation sequencing (NGS) and fluorescence in situ hybridization/karyotype testing. High-risk pts had t(4;14), t(14;16), or del17p abnormalities. Standard (std)-risk pts were confirmed negative for all 3 abnormalities. Minimal residual disease (MRD; 10–5) was assessed via NGS usin…