Sustained release gel enabling one stage treatment of prosthetic joint infection

Principal Investigator Overstreet Derek J Abstract Sonoran Biosciences Inc SBIR PAR Direct Phase II Prosthetic joint infections PJIs are especially costly requiring two surgeries at a cost of approximately $ per case to treat more than hip and knee replacement infections each year The near term outlook in this area is bleak with the number of infections growing over per year and few promising technologies on the horizon At the same time healthcare reforms are putting increasing economic pressure on hospitals tasked with managing PJIs PJIs are caused by bacteria in biofilms which require extreme sustained concentrations of antimicrobials to eradicate PJIs are treated with a combination of thorough surgical removal of the infected implant and tissues debridement followed by local delivery of high concentrations of antimicrobials to eradicate any residual biofilm contamination Currently local delivery is achieved using bone cement andquot spacersandquot which require removal A degradable local delivery formulation compatible with insertion of a permanent implant would enable effective PJI treatment in a single surgery improving patient outcomes and reducing costs by about half We have developed a new viscous controlled release carrier SB Gel which is capable of providing high and sustained antimicrobial concentrations over the entire surface of a joint prosthesis and throughout a surgical site SB Gel is the only material to combine sustained multi day antibiotic release to eliminate contamination in the surgical site including biofilm compatibility on implant surfaces and safe degradation to allow for normal healing Preliminary studies demonstrate that SB Gel provides appropriate release rates to kill biofilm does not hinder normal bone healing onto gel coated implants is safe at multiples of the human equivalent dose and is reliably effective in a model of one stage treatment of deep implant infection We now propose continuing development in a Phase II project to develop a formulation of SB Gel loaded with the antimicrobials tobramycin and vancomycin for treatment of PJI in a single surgery Tobramycin and vancomycin have collective activity against bacteria responsible for over of orthopaedic infections including PJIs Aim studies will ascertain the advantage of using two antimicrobials rather than one evaluate bone implant healing in a load bearing hip replacement model measure clearance of the SB Gel polymer after degradation and measure in vivo delivery rates Aim will focus on optimizing the gel formulation including evaluation of shelf life and development of a predictive model for critical quality attributes of the gel In Aim a selected formulation will be evaluated in GLP toxicity and pharmacokinetics studies in rats a key component of the definitive testing required to proceed to clinical trials Principal Investigator Overstreet Derek J Project Narrative Sonoran Biosciences Inc SBIR PAR Direct Phase II Infections after hip and knee replacement surgeries cost the U S healthcare system approximately $ per year This project seeks to develop a new gel based product which releases effective amounts of antibiotics at the infected area helping to remove the infection This technology has the potential to reduce the costs of treating these infections by about half