Spinal Fusion is an orthopaedic procedure which is usually carried out where a disc between vertebrae has worn out and pressure on the spinal cord or local nerves is giving rise to chronic back pain.  The vertebrae are fused together in order to limit mobility at that point in the spine and reduce the pressure on the nerves.

It is estimated that a half a million spinal fusions procedures are carried out each year in the United States. To encourage bone fusion, frequently bone is removed from another site in the body (often the hip) and inserted at the fusion point to encourage new bone growth.  This then results in two wound sites and some post-operative pain.  Drug treatment is with Bone Morphogenic Protein (rhBMP) applied through a collagen sponge.  When first introduced to the market this was rapidly taken up and used by surgeons.  However it was later determined that the BMP would leach out from where it was placed and would grow ectopic bone away from the intended site.  Between 15 and 20% of patients who are administered BMP experience post operative back and nerve pain due to ectopic bone growth within the spinal nerves.  Despite this, BMP is still used in approximately 25% of all spinal fusion surgeries, indicating that surgeons feel that there is a high need for such a product and they are prepared to take the risk.

The mechanism of action of Mesentech’s C3 is stimulation of maturation of osteoblasts (bone growth cells) and as these are found only within the bone, C3 should not bring about ectopic bone growth and potentially can quickly replace the usage of BMP and expand the market.