Biogen Idec and Elan Corp have launched the first clinical trial of their multiple sclerosis drug Tysabri for patients with relapsed or refractory multiple myeloma, the companies.

The first dose was administered on 4th September 2008. Multiple myeloma is a cancer of the plasma cell. Elan Corporation, plc and Biogen Idec 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.

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. 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.