|The following article features coverage from the American Society of Clinical Oncology 2019 meeting. Click here to read more of Hematology Advisor’s conference coverage.|
Daratumumab has shown clinical utility when added to the combination of lenalidomide and dexamethasone (Rd) for treatment of relapsed/refractory multiple myeloma (MM), but there is potential for outcomes to differ among patient subgroups.
A research team evaluated the efficacy of daratumumab plus Rd (D-Rd) treatment with regard to cytogenetic risk in patients with relapsed/refractory MM. The study results were presented at the 2019 American Society for Clinical Oncology (ASCO) Annual Meeting in Chicago, Illinois.
Patients in this study were participants in the POLLUX trial (ClinicalTrials.gov Identifier: NCT02076009) and were treated with either Rd (283 patients) or D-Rd (286 patients). All patients had received at least 1 line of prior therapy. Patients were grouped by cytogenetic risk. High-risk cytogenetic aberrations included t(4;14), t(14;16), or del(17p) changes, and they were present among 20.1% of patients receiving Rd and 17.1% of patients given D-Rd.
D-Rd showed improved responses in patients from both cytogenetic risk groups.
At a median follow-up of 44.3 months, high-risk patients on D-Rd showed a median progression-free survival (PFS) of 26.8 months, compared with a median PFS of 8.8 months for those receiving Rd (hazard ratio [HR], 0.54; 95% CI, 0.32-0.91; P =.0175).
Median PFS was not reached for standard-risk patients receiving D-Rd, compared with a median PFS of 19.9 months on Rd (HR, 0.41; 95% CI, 0.31-0.55; P <.0001).
Minimal residual disease (MRD) negativity (at the 10-5 sensitivity level) was also significantly more prevalent for patients receiving D-Rd in both risk groups. In the high-risk group, no patient achieved MRD negativity with Rd alone, but 28.6% of those receiving D-Rd did (P <.0001). In the standard-risk group, 8.2% of patients on Rd achieved MRD negativity, while 32.9% of patients given D-Rd did (P <.0001).
MRD-negative status at 12 or more months also showed more durability with D-Rd compared with Rd.
Overall, D-Rd appeared to substantially improve PFS and MRD negativity in both cytogenetic risk groups.
- Kaufman JL, Dimopoulos MA, Leiba M, et al. Efficacy and safety of daratumumab, lenalidomide, and dexamethasone (D-Rd) in relapsed or refractory multiple myeloma (RRMM): Updated subgroup analysis of POLLUX based on cytogenetic risk. Poster presentation at: 2019 ASCO Annual Meeting; June 3, 2019; Chicago, IL; Abstract 8038.