Scintigraphic Evaluation of a Novel Colon-Targeted Delivery System (CODES™) in Healthy Volunteers

Abstract

The purposes of this study are to investigate the gastrointestinal transit and release properties of a novel, colon-targeted delivery system (CODES™) administered to healthy volunteers using gamma scintigraphy and to confirm that lactulose functions to promote disintegration in the colon. Two placebo formulations were studied: one was CODES™, which consisted of a lactulose containing core overcoated with both Eudragit E and Eudragit L designed to rapidly disintegrate in the colon, the other was lactulose-free reference formulation (LFRF) that consisted of lactulose-free tablet core overcoated with the same materials. Transit and disintegration of the radiolabeled formulations were followed by gamma scintigraphy. In the fasted state, scintigraphic images indicated that CODES™ started to disintegrate in the ascending colon in the majority of subjects at 7.11 ± 2.01h post-dose. Disintegration was complete within 1h following commencement of in vivo release. In contrast, LFRF presented with prolonged in vivo disintegration properties. In the fed state, the disintegration period of CODES™ was almost comparable to that observed in the fasted state. Gamma scintigraphic studies clearly showed that CODES™ provides for rapid target site release in the colon regardless of the ingestion of food. © 2004 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 93:1287–1299, 2004