The U.S. Food and Drug Administration (FDA) has approved a supplemental Biologics License Application for the use of ofatumumab (Arzerra) in combination with fludarabine and cyclophosphamide for the treatment of patients with relapsed chronic lymphocytic leukemia (CLL). The application, which received Priority Review in May 2016, was submitted to the FDA by Novartis under the ofatumumab collaboration between Novartis and Genmab.
Approval for this indication by the FDA is based on results from the phase III COMPLEMENT 2 study, which evaluated ofatumumab in combination with fludarabine and cyclophosphamide vs fludarabine and cyclophosphamide alone in patients with relapsed CLL. Top-line results from COMPLEMENT 2 were reported in April 2015.
About COMPLEMENT 2
COMPLEMENT 2 is an open-label, two-arm, randomized, phase III study, which included 365 patients with relapsed CLL from 18 countries. Patients in the study were randomized 1:1 to treatment with up to six cycles of ofatumumab in combination with fludarabine and cyclophosphamide or up to six cycles with fludarabine and cyclophosphamide alone.
The primary endpoint of the study was progression-free survival, which was assessed by an independent review committee according to the International Workshop for Chronic Lymphocytic Leukaemia updated 2008 National Cancer Institute–sponsored Working Group guidelines. The study met the primary endpoint, with a median progression-free survival in patients receiving ofatumumab in combination with fludarabine and cyclophosphamide of 28.9 months, compared with 18.8 months in patients receiving fludarabine and cyclophosphamide alone (hazard ratio = 0.67, P = .0032).
Secondary endpoints included overall response rate, overall survival, patient-reported outcomes, time to response, duration of response, time to disease progression, time to next therapy, safety assessments, and quality of life. The safety profile in this study was consistent with that of other trials of ofatumumab, and no new safety signals were observed.
Ofatumumab is a human monoclonal antibody that is designed to target the CD20 molecule found on the surface of CLL cells and normal B lymphocytes. In the United States, ofatumumab is approved for use in combination with chlorambucil for the treatment of previously untreated patients with CLL for whom fludarabine-based therapy is considered inappropriate and for extended treatment of patients who are in complete or partial response after at least two lines of therapy for recurrent or progressive CLL. ■