Evaluation of Pharmacokinetic-Pharmacodynamic Relationships for BioRelease Meloxicam Formulations in Horses

The present study was designed to evaluate the pharmacokinetic-pharmacodynamic relationships for three controlled release meloxicam formulations in horses so as to select one for continued clinical evaluation. Twelve mature research horses of various light breeds were randomly assigned to one of the three treatment groups (n = 4 horses per group). Each horse received two consecutive intramuscular injections at 0 and 72 hours, containing 1,500 mg in 2 mL of one of three experimental BioRelease meloxicam formulations designed to maintain therapeutic blood concentrations (0.15–0.2 μg/mL) for 48 to 96 hours. Blood samples were collected pre and post-treatment. Injection site (0–3) and general well-being (normal or abnormal – with description) were recorded at the time of each blood collection. The plasma concentration-time curve for each horse was analyzed separately to estimate standard noncompartmental pharmacokinetic variables. Results from the present study suggest that potential therapeutic advantages of meloxicam may be enhanced by applying recent advances in biodegradable controlled release drug delivery, allowing single administration products to replace multiple daily treatment protocols.