title: Sustained delivery of intact drug to the colon: mesalamine formulation and temporal gastrointestinal transit analysis.
abstract: The goal was to use temporal gastrointestinal transit simulations and formulation to predict and provide sustained input of target-site directed oral drug delivery exclusively into the colon. Using mesalamine as the model drug for formulation coupled with stomach emptying rates (fed and unfed) plus intestinal transit times demonstrates concepts and provides a specific example for treatment in ulcerative colitis. Formulation involved extrusion and spheronization into beads which were then coated with aqueous Eudragit S. Drug is released only at colonic pH and gastrointestinal transit predicts sustained drug input into the colon, especially when food effects are included.
authors.affiliation: Department of Pharmaceutical Sciences, School of Pharmacy, Massachusetts College of Pharmacy and Health Sciences, Boston, Massachusetts 02115, USA. monica.chuong@mcphs.edu
authors.forename: Monica C
authors.initials: MC
authors.lastname: Chuong
authors.forename: J Mark
authors.initials: JM
authors.lastname: Christensen
authors.forename: James W
authors.initials: JW
authors.lastname: Ayres
mesh_terms: D000042:Absorption / Q000187:drug effects; D000284:Administration, Oral; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics*; D001682:Biological Availability; D002626:Chemistry, Pharmaceutical; D003106:Colon / Q000187:drug effects* / Q000378:metabolism; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics*; D004304:Dosage Forms; D005502:Food; D005772:Gastrointestinal Transit / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007408:Intestinal Absorption; D019804:Mesalamine / Q000008:administration & dosage / Q000378:metabolism / Q000493:pharmacokinetics*; D010599:Pharmacokinetics; D010602:Pharmacopoeias as Topic; D011109:Polymethacrylic Acids / Q000737:chemistry; D012995:Solubility; D013678:Technology, Pharmaceutical; D013997:Time Factors
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D004304:Dosage Forms; D011109:Polymethacrylic Acids; C038300:methylmethacrylate-methacrylic acid copolymer; D019804:Mesalamine