Phase III Castor study of Darzalex + Velcade (daratumumab + bortezomib and dexamethasone) in patients with relapsed or refractory multiple myeloma meets primary endpoint- Genmab

Genmab A/S announced that the Phase III Castor study (MMY3004) of Darzalex + Velcade (daratumumab + bortezomib and dexamethasone) versus bortezomib and dexamethasone in patients with relapsed or refractory multiple myeloma met the primary endpoint of improving progression free survival (PFS) in an interim analysis. The planned interim analysis was conducted by an Independent Data Monitoring Committee (IDMC). Daratumumab showed a tolerable safety profile in the interim analysis. Based on the IDMC’s recommendation, the study will be stopped early.

Patients originally assigned to the bortezomib plus dexamethasone treatment group will be offered the option of receiving daratumumab following confirmed disease progression. Patients will continue to be monitored for safety and overall survival. Further analysis of the safety and efficacy data is underway. Based on the interim data, Janssen Biotech, Inc., who licensed daratumumab from Genmab in 2012, will engage in a dialogue with health authorities about the potential for these data to serve as the basis for a regulatory submission for daratumumab in this indication. The Phase III study includes approximately 490 patients who had relapsed or refractory multiple myeloma. Patients were randomized to receive either daratumumab combined with subcutaneous bortezomib (a type of chemotherapy, called a proteasome inhibitor) and dexamethasone (a corticosteroid), or bortezomib and dexamethasone alone. The primary endpoint of the study is progression free survival.

Comment: Darzalex is the first monoclonal antibody (mAb) to receive FDA approval to treat multiple myeloma.