GlaxoSmithKline and Genmab A/S announced the submission of a Marketing Authorisation Application (MAA) to the European Medicines Agency (EMEA) for Arzerra (ofatumumab) for the treatment of chronic lymphocytic leukaemia (CLL). If approved, ofatumumab would be indicated for the treatment of patients with CLL who have previously failed, or are inappropriate for, standard therapies.

Ofatumumab targets a distinct binding site on the CD20 molecule of B-cells and it could become the first monoclonal antibody targeted to CD20 available for these patients. GSK and Genmab announced the submission of a Biologics License Application (BLA) to the US Food and Drug Administration (FDA) on Friday 30 January 2009.

CLL is the most common form of leukaemia in the Western world and patients have a high need for new therapy options. Currently fewer than 25 per cent of patients with refractory CLL respond to current treatments resulting in much poorer clinical outcomes.

"Ofatumumab is a new generation of monoclonal antibody that may provide an important new treatment for patients suffering from CLL and we plan additional studies to understand its potential in lymphomas and selected autoimmune diseases," said Carlo Russo, senior vice president BioPharm, GSK. "The filing of ofatumumab for refractory CLL represents the strong ongoing partnership between the GSK BioPharm and Oncology Units to develop therapies based upon novel biopharmaceutical platforms."

"The submissions of ofatumumab to the FDA and EMEA within a seven day period exemplify our commitment to providing new therapeutic options for patients with CLL," said Lisa N. Drakeman, Ph.D., chief executive officer of Genmab. "We are also collaborating with GSK to study ofatumumab in other conditions with the goal of providing important new treatment options to patients suffering from debilitating and life threatening diseases."

Ofatumumab is a novel, investigational, fully-human monoclonal antibody that targets a membrane-proximal (close to the cell surface) small loop epitope (a portion of a molecule to which an antibody binds) on the CD20 molecule of B-cells. This epitope is different from the binding sites targeted by other CD20 antibodies currently available. The CD20 molecule is a key target in CLL therapy because it is highly expressed in most B-cell malignancies.

Ofatumumab is being developed under a co-development and commercialisation agreement between Genmab and GlaxoSmithKline. It is not yet approved in any country. In Europe, ofatumumab has been granted orphan designation for CLL as it affects approximately 3.5 in 10,000 persons in the European Union.