Bayer Pharmaceuticals Corporation has initiated the phase III clinical trial to evaluate the safety and efficacy of Trasylol (aprotinin injection) in reducing blood loss and the need for transfusion in adult patients undergoing elective spinal fusion surgery.

Spinal fusion surgery involves fusing together one or more of the small bones of the spine with bone grafts and devices. This fusion limits the motion between the vertebrae allowing surgeons to treat injuries to the spine, repair broken vertebra, correct deformities, adjust abnormal curvatures, stabilize weakness and remedy slipped or herniated disks. Approximately 300,000 spinal fusion surgeries take place each year in the United States, a figure that has doubled in the last decade.

Patients undergoing spinal fusion surgery are subject to a blood transfusion rate that may be six times greater than that of patients undergoing spinal surgery without fusion. Spine fusion surgery is also associated with more complications (such as infection, chronic pain and neural injuries) as it requires more extensive dissection and longer operative time.

"Blood loss can be a significant complication of spine surgery. Combined with the potential health risks associated with transfusions and the rising cost of blood products, there is a great need to reduce bleeding in this surgical setting. Trasylol has been proven safe and effective in reducing blood loss and transfusion requirements in coronary artery bypass surgery, and we are studying the drug to determine if it may play a similar role in spinal fusion surgery," said Michael Neuwirth, lead investigator of the study and director of the Spine Institute at Beth Israel Medical Centre.

According to a company release, the multi-centre, randomised, double-blind, placebo-controlled trial will assess the ability of Trasylol to reduce bleeding and the need for blood transfusions in elective spinal fusion surgery involving three to seven vertebral levels. Over 450 adult patients will be randomly assigned to receive 200 ml of intravenous Trasylol or placebo at the start of the operation, followed by 50 ml/hour of either agent until the surgery is complete. Close to 40 investigational centres in North America will participate in the study.

Trasylol is currently approved for use in more than 60 countries. In the United States, Trasylol is indicated for prophylactic use to reduce perioperative blood loss and the need for blood transfusion in patients undergoing cardiopulmonary bypass (CPB) in the course of coronary artery bypass graft (CABG) surgery.

"Studies have continued to provide evidence supporting the haemostatic effects of Trasylol in orthopaedic surgery. We are hopeful that this clinical trial will validate those findings and establish the safety and efficacy of Trasylol therapy in the setting of spinal fusion surgery," said Dr. Paul MacCarthy, vice president of medical affairs at Bayer.

In April 2005, Bayer had announced the initiation of a phase III study to evaluate the safety and efficacy of Trasylol in reducing blood loss and the need for transfusion in patients undergoing elective primary total hip replacement surgery.

Trasylol, a broad-spectrum proteinase inhibitor, modulates the systemic inflammatory response associated with cardiopulmonary bypass (CPB) in the course of CABG surgery. Approved by the FDA in 1993, Trasylol is the only product indicated for prophylactic use to reduce perioperative blood loss and the need for blood transfusion in patients undergoing CPB in the course of CABG surgery.