The overall goal of this proposal is to develop a novel approach for the treatment of bacterial diseases in animals using unique and patented biodegradable injectable gel formulations for controlled release of the antibiotic ceftiofur. These novel biodegradable injectable gel formulations will be able to maintain therapeutic concentrations of ceftiofur for a prolonged period of time (7 days), following a single subcutaneous injection, thereby creating a product that will significantly improve the efficiency, effectiveness and duration of treatment, with the goal of reducing clinical relapse infection, and improving the percentage of treated animals experiencing complete recovery. Therefore, the specific aims of this study are as follows: 1) Evaluate In Vitro drug release rates from Novel Biodegradable Injectable Gels Loaded with Ceftiofur. The first step in this study will be to characterize critical factors affecting in vitro release rates of ceftiofur. 2) Ascertain How Long Therapeutic Plasma Concentrations of Ceftiofur can be Maintained In Vivo after a Single Subcutaneous Injection of the Novel Biodegradable Injectable Gel. The duration of therapeutic plasma concentration of ceftiofur released from optimized drug-loaded gel formulations will be examined in sheep following a single subcutaneous injection of the biodegradable gels. ANTICIPATED RESULTS & POTENTIAL COMMERCIAL APPLICATIONS OF RESEARCH Ceftiofur will be released from the biodegradable formulations in a controlled manner. Therapeutic concentrations of ceftiofur will be maintained in sheep for at least 7 days. Such a product would substantially reduce the stress and labor associated with animal handling for treatment purposes, and would likely result in improved efficacy due to reduction in treatment failures. Regarding commercialization potential, a United States patent application for the system has been granted. Patent applications for this novel biodegradable drug delivery system have also been filed in other countries, and are currently pending.
