Improved Treatment of Vertebral Compression Fractures for Elderly Patients Using an Image-Guided, Percutaneous Delivery of a Novel Bone Adhesive

Project Abstract Approximately 700,000 vertebral compression fractures (“VCF”) occur each year in the United States, costing an estimated $250 million in Medicare-related expenses. Compression fractures are most common among elderly individuals with osteoporosis, occurring in 20% of U.S. population over the age of 70. Eighty-four percent of patients with radiographic evidence of compression fractures report severe associated back pain. Historically, VCFs have been primarily treated using vertebroplasty and kyphoplasty, which are techniques involving the injection of polymethylmethacrylate (PMMA) into the vertebral body through a transpedicular approach under fluoroscopy. Significant pain relief is achieved in 70% to 90% of patients treated using these procedures. However, more recent clinical evidence has shown that these procedures are extremely risky with significant complications amplified by an underlying condition of osteoporosis, including graft dislodgement and subsistence, loss of implant fixation, and junctional kyphosis. PMMA cement causes thermal necrosis of adjacent bone tissue due to its high polymerization temperature. Its lack of biodegradability coupled with its higher modulus of elasticity (i.e., stiffness) compared to cancellous bone has also led to fractures in adjacent vertebrae. Most concerning is the risk of extravasation, or cement leakage, which has occurred in up to 75% of all reported cases resulting in pulmonary embolisms occurring in up to 23% of patients tracked in published literature. It is therefore not surprising that the prevalence of these procedures decreased by more than 70% from their peak since this information has come to light. Unfortunately, however, this has left many patients in chronic pain without a viable treatment option. To address this issue RevBio, Inc., has developed Tetranite® (TN), a novel bone adhesive biomaterial that can bond bone fragments together and fill bone voids. Over time this proprietary material acts as a scaffold, allowing bone to grow through it and ultimately replace it with new, vital bone. Research indicates that the material is also osteopromotive and accelerates bone healing and remodeling in osteoporotic patients. TN’s proven injectability, low exothermal temperature, biodegradability, intrinsic mechanical strength, lack of toxicity, and cohesive properties allowing it to infiltrate cancellous bone, make it a good candidate for replacing PMMA to enable the treatment of patients with VCFs who suffer from chronic pain. As a result, this proposed research seeks to achieve the following Aims: Aim 1: Optimization of the Percutaneous Delivery of TN for VCF Procedures and Aim 2: Demonstration of the Safe and Effective Use of TN in a Large Animal Pilot Study. The results from this pilot animal study (Aim 2), complemented with surgeon validated simulated use cadaver testing (Aim 1A), will be used as the basis for developing a pivotal animal study to initiate regulatory discussions with the FDA. Long term, RevBio’s mission is to provide surgeons with a novel product that will enhance fixation and reduce complications associated with treating vertebral compression fractures in the elderly.