Biodegradable Bone Graft Extender

描述(由申请人提供)：为了扩大骨替代材料的临床用途，剑桥科学公司建议开发一种可生物降解的骨移植延长器，该延长器能够增加自体移植物的工作量，而不损害其自体移植物的诱导能力。生物可降解延长器在自体移植物更可取的情况下将是有用的，但患者自己的骨储备不足。这项赠款申请的目标是在临床前开发一种基于可降解聚(丙二醇富马酸)(“PPF”)的骨移植延长剂，其中含有骨传导羟基磷灰石填充物，在植入骨缺损之前可以与骨诱导松质自体骨移植混合。在第一阶段SBIR可行性项目中，剑桥科学公司在一个小动物模型中证明，在自体移植骨中添加基于PPF的骨替代材料可以增强自体移植骨的骨整合，这反过来又对骨骼内长有影响。在PPF/自体移植促进新骨形成的这一演示之后，剑桥科学公司将在第二阶段评估这种延长器材料在大型动物(绵羊)缺陷模型中的使用，以解决延长器在重建重大骨骼缺陷中的最终临床应用。新骨的形成应与种植体的降解相结合，在整个修复过程中保持缺损处结构的完整性，骨诱导自体移植材料与具有骨传导能力和机械稳定性的可吸收支架相结合，在诱导和扩大新骨形成方面将具有吸引力。

DESCRIPTION (provided by applicant): In order to expand upon the clinical utility of bone replacement materials, Cambridge Scientific, Inc proposes to develop a biodegradable bone graft extender that has the ability to increase the working volume of autograft without compromising its inductive capacity of autograft Biodegradable extenders would be useful in situations in which autografts are preferable, yet the patient's own bone stocks are deficient. This grant application has as its goal the preclinical development of a degradable poly(propylene glycol-co-fumaric acid) ("PPF")-based bone graft extender containing osteoconductive hydroxylapatite fillers that can be mixed with osteoinductive cancellous autologous bone graft prior to implantation into a bony defect. In the Phase I SBIR feasibility project, Cambridge Scientific, Inc demonstrated in a small animal model that the addition of a PPF-based bone replacement material to autograft bone enhances osteointegratior of autograft which, in turn, has an effect on bony ingrowth. Following this demonstration of PPF/autograft enhancement of new bone formation, Cambridge Scientific, Inc will, in Phase II, evaluate the use of the extender material in a large animal (sheep) defect model to address the eventual clinical use of the extender in the reconstruction of significant skeletal defects. The development of new bone should couple to implant degradation in such a way that the structural integrity of the defect site is maintained throughout the recovery process Osteoinductive autograft material used in conjunction with an osteoconductive and mechanically stable resorbable scaffold would be attractive for both induction and expansion of new bone formation.