Small Ruminant Pharmacology and Drug Evaluation Center: Building Scalable Infrastructure for Minor Species Therapeutic Approval - There are limited approved therapeutics for use in sheep and goats, resulting in widespread extralabel drug use (ELDU) and creating significant challenges for veterinarians and producers. Extralabel antimicrobial use can increase the risk of violative drug residues, prolonged withdrawal intervals, and antimicrobial resistance when species-specific pharmacokinetic, efficacy, and antimicrobial stewardship data are lacking. Despite the importance of the small ruminant industry, economic barriers often limit pharmaceutical investment in therapeutic approval for small ruminants, leaving veterinarians with few approved treatment options and limited evidence-based guidance. To address this unmet need, our long-term goal is to establish the Small Ruminant Pharmacology and Drug Evaluation Center, an integrated framework designed to accelerate therapeutic evaluation and facilitate future drug approvals in small ruminants. The Center consists of four complementary Cores: Administrative and Partnership, Pharmacology and Residue, Antimicrobial Stewardship, and Data Integration. Together, these Cores will generate the pharmacologic, microbiologic, residue depletion, antimicrobial resistance, and clinical outcome datasets required to support assessment of safety, effectiveness, food safety, and antimicrobial stewardship in minor species. To demonstrate the feasibility of this framework, we will conduct a pilot study using florfenicol, one of the most used extralabel antimicrobials in small ruminants. Pharmacokinetic studies in healthy sheep and a naturally occurring respiratory disease field trial will generate target-site and population-based pharmacokinetic data to support evaluation of drug safety and effectiveness. Antimicrobial susceptibility interpretive criteria and breakpoint-supportive datasets will be developed for small ruminant respiratory pathogens, while longitudinal resistome analyses will characterize antimicrobial resistance dynamics and evaluate the potential for resistance gene persistence through withdrawal intervals and at the time of slaughter. Successful completion of this pilot project will establish the feasibility of a scalable and reusable framework for therapeutic evaluation in small ruminants. The proposed Center will provide a foundation for future therapeutic approvals while advancing antimicrobial stewardship, food safety, evidence-based drug use, and producer confidence. Future Center activities will apply this framework to additional medically important antimicrobials, nonsteroidal anti-inflammatory drugs, anthelmintics, and analgesics, creating a sustainable pathway for therapeutic development in minor species.
