Pioneering new bone graft material to improve patient outcomes

Every year, up to 1.6 million people undergo spinal fusion surgery requiring a bone graft substitute. Due to the use of traditional bone grafts, more than one fifth of these procedures fail, leaving a significant proportion of sufferers with a reduced quality of life and unable to return to work.

Now a treatment developed at the University of Aberdeen and successfully spun out into a multi-million-pound company has the potential to dramatically improve patient outcomes.

The drawbacks of current spinal surgery solutions

Eight out of ten people experience back pain at some point in their lives, and around eight percent of adults suffer from persistent or chronic back problems that limit them in some way in everyday life. Spinal fusion is a common surgical procedure often employed to correct a deformity, increase a sufferer’s stability or to reduce pain, and involves fusing multiple vertebrae together into a single solid bone, which in turn improves spinal alignment. To enable the bones to fuse together, the surgery requires the deployment of additional bone material which encourages the body’s own bone to grow across the gap between vertebrae. This additional material is known as ‘bone graft’.

There are three common types of bone graft. They are:

1) Autograft - When bone from another part of the patient’s body is taken and used for the procedure

2) Allograft - When donor bone from another person is used for the procedure

3) Synthetic bone graft substitute - When another material other than bone is used for the procedure.

Each of these methods has potential drawbacks. As autograft bone needs to be taken from another part of the patient’s body, an additional procedure to remove it is required, and there is the potential for more post-operative pain.

Allograft bone takes much longer to heal and comes with a risk of infection or disease transmission, while traditional synthetic substitute materials are ceramic-based, can have limited strength and encourage fibrous tissue growth rather than new bone, hence they come with a high failure rate and/or very slow healing rates.

An innovative approach to material development

As such, there has long been demand in the sector for an artificial solution without these drawbacks. Research in this field at the University of Aberdeen was recognised back in 2005 when the EPSRC awarded an Advanced Research Fellowship to Professor Iain Gibson with the goal of developing novel synthetic bone graft substitute using brand new approaches to synthesising these materials.

Together with Professor Jan Skakle and Professor Richard Aspden, Gibson secured a Scottish Enterprise Proof of Concept award in 2007 to develop a bone graft scaffold material at least as effective as autograft, the previous clinically preferred graft type, without the need to harvest additional bone from the patient and deal with the difficulties that this presents. Any proposed solution must have similar chemical and morphological properties to bone mineral in order to facilitate faster bone growth and be capable of cell-mediated resorption, the process whereby this support material breaks down, leaving the fused ‘real’ bone behind.

Dr Jordan Conway and Professor Iain Gibson

The culmination of the team’s research was the development of a brand new silicate-containing calcium phosphate material with properties much closer to the mineral crystals found in real bone than had been previously achieved in any other synthetic bone graft material. By processing the material to have smaller crystal dimensions and notably smaller pores than other synthetic solutions, the material achieves a much higher surface area, with the result that the surface supports bone repair more effectively and is more readily remodelled than traditional ‘ceramic’ substitutes.

In a pre-clinical comparison with a common commercially available synthetic bone graft substitute it was observed that bone formation when using the newly developed material was significantly faster than the one already in use and that the graft material was successfully resorbed and replaced by new bone. In a more recent regulatory pre-clinical study of the final product, tests showed 100% fusion success after 26 weeks, a remarkable result.

Industry recognition and commercial success

Following the successful Proof-of-Concept project, Professor Gibson’s team were shortlisted for major innovation awards and won the prestigious Venture Prize from The Worshipful Company of Armourers and Brasiers. The concept and research warranted the formation of spin-out company SIRAKOSS, with a view to readying the new technology for market.

Investors and Innovate UK were quick to back the new material, quickly pledging upwards of £6 million to develop the product for commercialisation, and in November 2020 the company was acquired by OssDsign in a deal initially worth £8.4 million, with the potential for additional future payments dependent on royalties and milestones. This will enable their new products to be marketed across the USA and Europe, with the aim of capturing part of a bone graft market worth over £2.25 billion per year.

Impacts

Addresses the clinical need for an effective and affordable synthetic bone graft substitute that accelerates bone formation and has a success rate at least as comparable with autograft procedures while removing the need for time-consuming, expensive and potentially risky bone harvesting from patients or donors.
The formation of SIRAKOSS, a multi-million pound spin-out company with the aim of bringing the exciting technology to the market by obtaining regulatory approvals. The company has attracted significant investment and seen notable growth, creating jobs for 7 full-time employees.
Forms the basis of research into new applications of the technology for new products beyond spinal surgery, including use in trauma surgery.
Industry recognition of the technology and its potential, including winning the 2014 Venture Prize from The Worshipful Company of Armourers and Brasiers and being shortlisted twice in the Scottish Enterprise Life Science Awards.