The FDA has approved a supplemental Biologics License Application for the use of ofatumumab (Arzerra) in combination with fludarabine and cyclophosphamide (FC) for the treatment of patients with relapsed chronic lymphocytic leukemia (CLL).
Approval for this indication by the FDA is based on results from the phase III COMPLEMENT 2 study that evaluated ofatumumab in combination with FC versus FC alone in patients with relapsed CLL. Top-line results from COMPLEMENT 2 were reported in April 2015.
COMPLEMENT 2 is an open-label, two-arm, randomized, phase III study, which included 365 patients in 18 countries with relapsed CLL. 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 study met the primary endpoint with a median progression free survival in patients receiving ofatumumab in combination with FC of 28.9 months, compared to 18.8 months in patients receiving FC alone (HR =0.67, p=0.0032). Secondary endpoints included overall response rate, overall survival, patient reported outcomes, time to response, duration of response, time to progression, time to next therapy, safety assessments, and quality of life. The safety profile observed in this study was consistent with 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 U.S., 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 in complete or partial response after at least two lines of therapy for recurrent or progressive CLL.