On June 16th 2017 the US Food and Drug Administration (US FDA) granted approval of Genmab’s Darzalex® (daratumumab) for the treatment of Multiple Myeloma (MM) in combination with pomalidomide (Pomalyst®) and dexamethasone. Daratumumab is a humanized monoclonal antibody against CD38. This new indication enables treatment of relapsed and refractory (RR) MM patients that have received 2 or more prior therapies, including lenalidomide and a proteasome inhibitor (PI).
Approval was granted following data from a Phase Ib study (MMY1001, EQUULEUS), in which 103 patients were treated with 16 mg/kg of daratumumab in combination with standard doses of the backbone treatments of pomalidomide and dexamethasone. Treatment resulted in an overall response rate (ORR) of 59% (95% CI, 49.1-68.8), very good partial response (vGPR) of 28%, partial response (PR) of 17.5%, complete response (CR) of 5.8% and stringent CR in 7.8% of patients. The median time to response was 1 month (range: 0.9 to 2.8 months) and median duration of response was 13.6 months (range: 0.9+ to 14.6+ months). Serious adverse effects (AEs) were reported in 49% of patients, with infusion reactions (50%), diarrhea (38%), fatigue (50%), and, upper respiratory tract infection (50%) the most commonly reported. In addition, neutropenia occurred in 82% and lymphopenia in 71% of patients. Infusion reactions pose the largest problem, but appear to be treatable.
Daratumumab is currently approved in both the US and EU for use in combination with either lenalidomide and dexamethasone, or bortezomib and dexamethasone, for the treatment of RRMM patients who have received at least one prior therapy, or as a monotherapy for RRMM patients who have received at least three prior lines of therapy.
This will be welcome news for Genmab who have several more clinical trials underway in order to further extend the treatment indications for daratumumab across a variety of drug regimens and to encompass different patient subsets.