Related Experiment Video
Updated: Dec 11, 2025
Interphase Fluorescence in situ Hybridization of Bone Marrow Smears of Multiple Myeloma
Published on: April 15, 2022
Daratumumab, bortezomib, and dexamethasone in relapsed or refractory multiple myeloma: subgroup analysis of CASTOR
Katja Weisel1, Andrew Spencer2, Suzanne Lentzsch3
1Department of Oncology, Hematology and Bone Marrow Transplantation with Section of Pneumology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. k.weisel@uke.de.
Background:
Multiple myeloma (MM) patients with high cytogenetic risk have poor outcomes. In CASTOR, daratumumab plus bortezomib/dexamethasone (D-Vd) prolonged progression-free survival (PFS) versus bortezomib/dexamethasone (Vd) alone and exhibited tolerability in patients with relapsed or refractory MM (RRMM).
Methods:
This subgroup analysis evaluated D-Vd versus Vd in CASTOR based on cytogenetic risk, determined using fluorescence in situ hybridization and/or karyotype testing performed locally. High-risk patients had t(4;14), t(14;16), and/or del17p abnormalities. Minimal residual disease (MRD; 10-5 sensitivity threshold) was assessed via the clonoSEQ® assay V2.0. Of the 498 patients randomized, 40 (16%) in the D-Vd group and 35 (14%) in the Vd group were categorized as high risk.
Results:
After a median follow-up of 40.0 months, D-Vd prolonged median PFS versus Vd in patients with standard (16.6 vs 6.6 months; HR, 0.26; 95% CI, 0.19-0.37; P < 0.0001) and high (12.6 vs 6.2 months; HR, 0.41; 95% CI, 0.21-0.83; P = 0.0106) cytogenetic risk. D-Vd achieved deep responses, including higher rates of MRD negativity and sustained MRD negativity versus Vd, regardless of cytogenetic risk. The safety profile was consistent with the overall population of CASTOR.
Conclusion:
These updated data reinforce the effectiveness and tolerability of daratumumab-based regimens for RRMM, regardless of cytogenetic risk status.
Trial Registration:
ClinicalTrials.gov, NCT02136134 . Registered 12 May 2014.
