Large bone defect sites such as critically sized bone defects can occur in up to 20% depending on the initial injury. These defects are commonly filled with bone grafts to guide and assist the body’s regeneration response amounting to more than 4 million surgeries per year. However, bone grafts are avascular structures that suffer from only limited supply of nutrients and oxygen, leading to a loss of their essential functionality for tissue healing and regeneration. This causes a failure rate of the healing process as high as 50%, necessitating expensive re-operation procedures and even then, the chance of failure and the resulting amputation for complex lower limb fractures is >10%. Additionally, the burden of these defects on the patients are substantial and typically include pain, loss of function and psychological distress as well as a significant financial burden due to loss of potential earnings and overall medical expense of up to €92.000 per case. Although various bone grafting strategies have been developed, e.g. allografts (bone from human donors) or bone substitute materials, they do not address the loss of implant viability and at best remain comparable to the gold standard in autografting (patient bone) but suffer from the same limitations. Although new strategies are being developed, they mostly showcase potential in vitro only due to their inability to prevent implant starvation in large implants. Thus, a strategy to metabolically support implants and thus enable efficient bone healing, which will drastically improve surgical outcomes, is required to treat large bone defect sites. Despite this urgent need, no such strategy is currently available.
NutriBone's value proposition is to revolutionize bone grafting by providing self-feeding properties to already existing methods/ technologies to maintain essential graft viability to enhance vascularization and bone regeneration. Our solution aims to be readily compatible with current clinical practice, while offering high scalability towards large and otherwise untreatable bone defects as well as a high level of safety. By keeping living implants viable, we can improve surgery outcomes, reduce expensive re-operation and ensure a higher quality of live and faster reintegration into society of the patients. Specifically, we have discovered natural nutrient deposits that cells enzymatically degrade to release the nutrients upon need. Endowing implants with these nutrient deposits preserves their viability under oxygen deprived conditions similar to the post-implantation environment. This translated to accelerated vascular ingrowth and implant remodeling, showcasing the high potential of our approach to the current limitations of large bone grafts and cellular implants in general.