An interim analysis of the phase 3 CASTOR trial evaluating the efficacy and safety of daratumumab in combination with bortezomib and dexamethasone demonstrated that the regimen had superior progression-free survival compared with bortezomib and dexamethasone alone in patients with relapsed or refractory multiple myeloma.1
“These results suggest daratumumab could potentially be used in combination with standard therapy in patients with relapsed or refractory multiple myeloma,” said Peter F. Lebowitz, MD, PhD, Global Oncology Head, Janssen Research & Development.
Because the study achieved its primary endpoint, it will be stopped early per the Independent Data Monitoring Committee’s recommendation.
For the international, open-label, controlled study, researchers enrolled approximately 490 patients with relapsed or refractory multiple myeloma. Patients were randomly assigned to receive either daratumumab in combination with subcutaneous bortezomib and dexamethasone, or bortezomib and dexamethasone alone. Patients were treated until disease progression or unacceptable toxicity.
Daratumumab was administered at a dose of 16 mg/kg intravenously weekly for the first 3 cycles, on day 1 of cycles 4 to 9, and then every 4 weeks thereafter. Patients in both arms received bortezomib 1.3 mg/m2 subcutaneously on days 1, 4, 8, and 11 of each 21-day cycle for 8 cycles and dexamethasone 20 mg orally on days 1, 2, 4, 5, 8, 9, 11, and 12 for 8 cycles.
The results, which showed that the immunotherapy combination improved progression-free survival compared with bortezomib and dexamethasone alone (P < .0001), will be submitted for presentation at an upcoming medical congress and for publication in a peer-reviewed journal.
RELATED: Novel Dual HDAC/PI3K Inhibitor Assessed in Lymphoma, Myeloma
Daratumumab, a human CD38-directed monoclonal antibody, was initially approved by the U.S. Food and Drug Administration in 2015. It is indicated for the treatment of patients with multiple myeloma who have received at least 3 prior lines of therapy including a proteasome inhibitor and an immunomodulatory agent or who are double-refractory to a proteasome inhibitor and an immunomodulatory agent.
- First phase 3 trial of daratumumab in combination with standard therapy in relapsed/refractory multiple myeloma meets primary endpoint in planned interim analysis [news release]. Raritan, NJ: Janssen; March 30, 2016. http://janssen.com/first-phase-3-trial-daratumumab-combination-standard-therapy-relapsedrefractory-multiple-myeloma. Accessed April 1, 2016.