3.2.5. Ex Vivo Pharmacokinetic Studies

To assess the pharmacokinetics of FTS in local tissue, ex vivo studies were performed using fresh porcine esophageal tissue with pre-loaded and post-loaded fluticasone rings (*n* = 3 per timepoint). The FTS concentration in esophageal tissue was determined using LC-MS/MS. Results demonstrated that sustained levels of FTS were detected in all samples over 14 days (Supplementary Figure S3). These results demonstrate that FTS was effectively diffused from the rings and highly accumulated in the esophageal tissue.
