Addition of Isatuximab to Pomalidomide/Dexamethasone in Multiple Myeloma
Posted: Wednesday, July 3, 2019
The addition of isatuximab, an anti-CD38 monoclonal antibody, to pomalidomide and low-dose dexamethasone improved both progression-free survival and overall response in patients with relapsed or refractory multiple myeloma. Paul G. Richardson, MD, of the Dana Farber Cancer Institute in Boston, and colleagues, who presented the results of their phase III trial at the 2019 American Society for Clinical Oncology (ASCO) Annual Meeting in Chicago (Abstract 8004), consider this triplet therapy an “important new treatment option” in this patient population.
A total of 307 patients with relapsed or refractory multiple myeloma who had received more than 2 prior lines of therapy were included in the study. Patients were randomly assigned to receive either isatuximab plus pomalidomide/dexamethasone or pomalidomide/dexamethasone alone.
At a median follow-up of 11.6 months, the median progression-free survival was 11.5 months with isatuximab and 6.5 months without it (hazard ratio = 0.596). This progression-free survival benefit was seen among all subgroups of patients. The overall response rate was increased from 35.3% with pomalidomide/dexamethasone alone to 60.4% with the addition of isatuximab. At the date of analysis, the overall survival could not be calculated, but there appeared to be a trend toward improvement for patients receiving the triplet therapy.
The median treatment time was 41 weeks for the isatuximab group and 24 weeks for the control group. Grade 3 or higher adverse events were seen in 86.8% of patients treated with isatuximab, compared with 70.5% of patients who were not treated with the drug. Grade 3 infections were seen in both the triplet-therapy group and the doublet-therapy group, 42.8% and 30.2% respectively. In addition, grade 3 or higher neutropenia was seen in 84.9% of patients treated with isatuximab and 70.1% of patients not treated with isatuximab.
Disclosure: The study authors’ disclosure information may be found at coi.asco.org.
