A second monoclonal antibody for use in the treatment of multiple myeloma has been approved by the US Food and Drug Administration (FDA). The latest product is elotuzumab (Empliciti, Bristol-Myers Squibb Company). It joins the first monoclonal antibody for multiple myeloma, daratumumab (Darzalex, Janssen Pharmaceuticals, Inc), which was approvedjust 2 weeks ago.
Elotuzumab has been approved for use in combination with lenalidomide (Revlimid, Celgene Corporation) and dexamethasone (multiple brands) in patients with multiple myeloma who have previously received one to three other therapies.
The approval is based on a trial known as ELOQUENT-2, a randomized, open-label clinical study that included 646 participants with multiple myeloma who had experienced relapse or who had not responded to previous treatment. The addition of elotuzumab to the combination of lenalidomide and dexamethasone extended progression- free survival to 19.4 months, as compared with 14.9 months seen in patients treated with lenalidomide and dexamethasone. Additionally, the overall response rate (including complete and partial responses) was 78.5%, compared with 60.1% in patients receiving lenalidomide and dexamethasone.
"It was particularly striking that the difference between the elotuzumab and control groups seems to get bigger over time, which really speaks to the power of this immune-based approach," lead study author Sagar Lonial, MD, chief medical officer of the Winship Cancer Institute of Emory University and professor and executive vice chair of the Department of Hematology and Medical Oncology at Emory University School of Medicine, in Atlanta, commented earlier this year. This separation of the curves and the maintenance of benefit over time has been seen with other immune-based approaches, such as programmed death inhibitors, he added.
Dr Lonial was speaking about the study at a media presscast before the 2015 American Society of Clinical Oncology annual meeting, where the study was presented. ASCO President Julie M. Vose, MD, MBA, commented: "We've made much headway over the past decade in understanding and treating multiple myeloma, the third most common blood cancer. This study is an innovative approach — one that combines the precision of a targeted, immune-based therapy with traditional myeloma therapy. The results are very encouraging, giving renewed hope to patients who have relapsed."
Elotuzumab is a monoclonal antibody that targets the cell-surface protein SLAMF7, which is found on both myeloma cells and NK cells. It offers a two-pronged attack on cancer by targeting myeloma cells directly and by enhancing the NK cells' ability to kill myeloma cells. "It's a bit of a double whammy," commented Dr Lonial.
He also said that adding elotuzumab to the standard therapy did not significantly increase the adverse events that were reported. Overall, the drug was well tolerated and did not cause a deterioration of patients' quality of life or exacerbate symptom burden.
The FDA noted that the most common side effects of elotuzumab are fatigue, diarrhea, pyrexia, constipation, cough, peripheral neuropathy, nasopharyngitis, upper respiratory tract infection, decreased appetite, and pneumonia.
The agency also noted that elotuzumab was awarded breakthrough therapy designation for this application, as well as priority review and orphan drug designation.