Sequential ofatumumab and lenalidomide for the treatment of relapsed and refractory chronic lymphocytic leukemia and small lymphocytic lymphoma

Abstract

Ofatumumab is a fully human anti-CD20 monoclonal antibody with enhanced antibody dependent and complement dependent cytotoxicity. Lenalidomide induces T cell and natural killer (NK) cell activation and in vitro enhances clearance of chronic lymphocytic leukemia (CLL) cells by monoclonal antibodies. We performed a multi-center, phase 2 trial of sequential treatment with ofatumumab and lenalidomide in patients with advanced, relapsed and refractory (R/R) CLL, consisting of ofatumumab 2000 mg intravenously on day 1 and lenalidomide 10 mg on days 8–28, for up to six cycles. Twenty-one subjects were included with median age of 63 years and two prior lines of therapy. The overall response rate was 47.6% and 23.8% had stable disease. Median overall survival was 21.5 months. Neutropenia and thrombocytopenia were the most frequent adverse events. Tumor flare reaction occurred in 43% of subjects. Intracycle sequential ofatumumab plus lenalidomide is active in high-risk R/R CLL and well tolerated except for frequent cytopenias.

Keywords::

• Ofatumumab
• lenalidomide
• chronic lymphocytic leukemia
• small lymphocytic lymphoma
• clinical trial

Acknowledgments

GlaxoSmithKline provided financial support and study drug (ofatumumab). Celgene provided study drug (lenalidomide).

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal.