Elan Corporation, plc (NYSE: ELN) and Biogen Idec (NASDAQ: BIIB) announced the initiation of the first clinical trial of TYSABRI® (natalizumab) in oncology. The first dose of TYSABRI was administered yesterday in the trial. The objectives of this Phase I/II study are to evaluate the safety and potential anti-tumor activity of TYSABRI in patients with relapsed or refractory multiple myeloma. TYSABRI is a recombinant, humanized monoclonal antibody that targets the adhesion molecule VLA4 (also known as alpha-4 integrin) that is expressed on the surface of many types of immune cells. VLA4 is also found on the surface of multiple myeloma cells and may be involved in their survival.

"We are excited to initiate the oncology clinical trial program for TYSABRI," said Wayne Saville, MD, Director, Oncology Medical Research at Biogen Idec. "TYSABRI has potential in multiple myeloma and a number of other cancers through its action as a blocker of VLA4. It is a meaningful addition to Biogen Idec's robust oncology pipeline."

"This clinical trial in oncology represents an opportunity for TYSABRI to continue to address unmet medical needs, potentially bringing new therapeutic options to patients and their oncologists," said Gordon Francis, MD, Senior Vice President, Global Clinical Development at Elan Pharmaceuticals, Inc.

About the Trial

This Phase I/II, open-label, two-arm study is designed to evaluate the safety and anti-tumor activity of TYSABRI in patients with relapsed or refractory multiple myeloma. In the Phase I portion of the trial, a standard dose-escalation design will be used to assess the safety and tolerability of TYSABRI in up to 12 patients. In the Phase II portion of the study, up to 30 patients will be randomized to the tolerated doses identified in Phase I of the study.

Treatment cycles will consist of intravenous infusions of TYSABRI once every 28 days for 6 months. After 6 months, if the patient has achieved a partial or a complete response, he or she may continue to receive TYSABRI once every 28 days until progression of disease occurs.

Patients eligible for the study must be at least 18 years of age with relapsed or refractory multiple myeloma who have failed or cannot tolerate therapy with bortezomib and thalidomide or lenalidomide.

About Multiple Myeloma

Multiple myeloma is a cancer of the plasma cell, an important part of the immune system that produces antibodies to help fight infection and disease. Certain immune cells, called B cells, change into plasma cells when they respond to an antigen, producing antibodies to attack bacteria and viruses. However, when plasma cells multiply in an uncontrolled way, they can produce tumors, which generally develop in the bone marrow. These plasma cells produce excessive amounts of antibodies and can interfere with normal blood-forming functions of the bone marrow, crowding out healthy cells and leaving patients susceptible to anemia, hemorrhage, infection and severe osteoporosis.

Multiple myeloma is the second most common blood cancer in the United States (US). More than 50,000 people in the US are living with multiple myeloma, and about 20,000 new cases are expected to be diagnosed this year. Nearly 11,000 Americans are expected to die from the disease this year. Men are 50 percent more likely to develop the disease than women. Other risk factors include race, radiation exposure, family history, occupational exposure to petroleum, obesity and other plasma cell disorders.

About TYSABRI

TYSABRI is a treatment approved for relapsing forms of MS in the United States and relapsing-remitting MS in the European Union. According to data that have been published in the New England Journal of Medicine, after two years, TYSABRI treatment led to a 68% relative reduction (p