Controlled Release of Ceftiofur from Biodegradable Injectable Delivery Systems

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.