CASCADE Study: Amedica Responds to FDA

Amedica Corporation has submitted its responses to the Food and Drug Administration (FDA) in relation to the CASCADE clinical trial, a study that compared the 24-month outcomes from single-level cervical fusion between Amedica’s porous silicon nitride versus bone autograft. As indicated in the June 13, 2016 news release, “Data showed that porous silicon nitride achieved clinical and radiographic outcomes that were comparable to bone autograft.”

“Porous silicon nitride is a synthetic platform that can achieve spinal fusion without added bone graft, based on the results of our clinical trial, ” said Amedica Chairman and CEO Sonny Bal, M.D. “These outcomes are consistent with our understanding of the surface chemistry and nano-topography of silicon nitride. We believe the composite porous silicon nitride fusion device used in the CASCADE trial, if approved by the FDA, will improve patient health. We are confident that we have addressed the questions raised by the FDA.”

Asked what issues are involved with the surface chemistry and nano-topography, Dr. Bal told OTW, “Surface chemistry and nano-topography studies show that the surface of silicon nitride is favorable for cell adhesion, hydroxyapatite deposition, and antimicrobial properties. All of these properties have been validated and described extensively in our published works in the peer literature. Furthermore, we are able to modulate the surface properties of silicon nitride, thereby optimizing specific material attributes of interest.

“Examination of the surface of silicon nitride shows bioglass formation, because of an interaction between the constituent elements of the material. As orthopedic surgeons will recognize, silicate-based bioglasses have been used extensively to make hydroxyapatite coatings for implants, as well as a number of commercially available bone fillers and putties that are used during spine fusion surgery, to enhance bone healing. While other materials, such as PEEK, require surface enhancements or treatments with porous metals and hydroxyapatite sprays, silicon nitride is inherently osteogenic, because of the unique surface properties of the material. This is a key advantage and differentiation of the material.”