Daratumumab-Based Regimens and Minimal Residual Disease in Patients With Myeloma
Posted: Monday, March 29, 2021
Patients with multiple myeloma who achieve sustained minimal residual disease (MRD)-negative status tend to have durable remissions and improved clinical outcomes. An exploratory analysis of the POLLUX and CASTOR studies, reportedly the largest set of MRD data in patients with relapsed or refractory multiple myeloma, indicated that daratumumab-based treatment combinations might induce higher rates of sustained MRD negativity compared with the standard of care. The report was published in the Journal of Clinical Oncology.
“Achieving durable MRD negativity may predict long-term outcomes, as durable MRD negativity improves progression-free survival and increases the time between treatment relapses for relapsed or refractory multiple myeloma,” Hervé Avet-Loiseau, MD, of the Institut Universitaire du Cancer, Toulouse, France, and colleagues reported.
Patients in the CASTOR study were randomly assigned to receive daratumumab, bortezomib, dexamethasone (n = 251), or bortezomib dexamethasone alone (n = 283). In the POLLUX study, patients were randomly assigned to receive daratumumab, lenalidomide, and dexamethasone (n = 286) or lenalidomide and dexamethasone alone (n = 283). Sustained MRD negativity was evaluated in the intention-to-treat populations and the suspected complete response populations.
Among the intention-to-treat population, patients treated with daratumumab in the POLLUX study achieved higher MRD negativity rates than did those who received lenalidomide and dexamethasone (32.5% vs. 6.7%; P < .0001). Similarly, in the CASTOR study, patients treated with daratumumab achieved higher MRD negativity rates than did those treated with bortezomib and dexamethasone alone (15.1% vs. 1.6%; P < .0001). In both studies' suspected complete response populations, patients treated with daratumumab-containing regimens achieved significantly higher rates of MRD negativity than did those who did not (P < .005). Higher rates of sustained MRD negativity were observed among patients in both studies who received daratumumab than those who did not (P < .0001). These higher sustained MRD negativity rates tended to be associated with prolonged progression-free survival.
Disclosure: For full disclosures of the study authors, visit ascopubs.org.
