GlaxoSmithKline (GSK) and Genmab A/S (OMX: GEN) have announced the accelerated approval of ArzerraTM (ofatumumab) from the FDA for use in patients with chronic lymphocytic leukemia (CLL) that is refractory to fludarabine and alemtuzumab. “The approval of Arzerra brings an important new treatment option to patients with refractory CLL.” said Lisa N. Drakeman, Ph.D., Chief Executive Officer of Genmab. “This approval also marks a key milestone for Genmab as it is our first antibody to reach the market. All of us involved in the development of Arzerra are pleased that we have been able to move the product so quickly through research and development and meet our goal of providing this innovative therapy to patients.” The approval is based on results from a pivotal study in which 42% of patients with CLL who were refractory to both fludarabine and alemtuzumab (two therapies used in treating CLL) responded to treatment with Arzerra. These patients had a median duration of response of 6.5 months. The most common adverse reactions (?10%) seen were neutropenia, pneumonia, pyrexia, cough, diarrhea, anemia, fatigue, dyspnea, rash, nausea, bronchitis, and upper respiratory tract infections. The most common serious adverse reactions seen were infections (including pneumonia and sepsis), neutropenia, and pyrexia. “Arzerra is a significant step forward in helping patients and physicians better manage the challenges of refractory CLL. Patients now have a new choice,” said Kathy Rouan, Ph.D., Vice President and Medicines Development Leader at GlaxoSmithKline. “The Arzerra approval demonstrates the commitment of the GSK BioPharm and Oncology Units to developing new biopharmaceutical treatment options for cancer patients.” Arzerra is a monoclonal antibody that causes the body’s immune response to fight against normal and cancerous B-cells. Arzerra attaches to the small and large loop epitopes – on a molecule called CD20, which is found on the surface of B-cells, the type of cell which becomes cancerous in CLL. The approval of Arzerra was supported by a positive recommendation by the FDA’s Oncologic Drugs Advisory Committee (ODAC) at ASCO on May 29, 2009, in which the panel voted, 10-3, that the data for Arzerra were likely to predict clinical benefit for patients with CLL whose disease is refractory to fludarabine and alemtuzumab. Arzerra is anticipated to be available for prescription use in the coming weeks.