5-aminosalicylic acid release from a new controlled-release mesalazine formulation during gastrointestinal transit in healthy volunteers.
BACKGROUND
Mesalazine (5-aminosalicylic acid, 5-ASA) containing formulations represent a cornerstone in the treatment of inflammatory bowel diseases. A novel formulation with an Eudragit L/S mixture coating has been developed to provide selective release of 5-ASA to the ileo-caecal region and the colon.


OBJECTIVE
To determine the release of 5-ASA during the gastrointestinal transit.


METHODS
A single oral dose of mesalazine EC 500 mg gastroresistant tablets (Asamax) was administered to eight healthy male volunteers. Gastrointestinal transit and tablet disintegration were monitored by scintigraphy. 5-ASA release was verified by assessing plasma pharmacokinetics.


RESULTS
Initial tablet disintegration was observed 5.65 +/- 0.86 h after dosing, corresponding to the detection of 5-ASA in plasma. This occurred in the ileo-caecal region in three subjects and the ascending colon in the remaining five. The relative percentage of 5-ASA absorption was more pronounced in the ascending colon (41 +/- 27.4%) than the ileo-caecal region (6.6 +/- 9.2%).


CONCLUSIONS
This mesalazine EC gastroresistant tablets release locally active 5-ASA specifically in the ileo-caecal region and the ascending colon.
Brunner
M
M
Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria. martin.brunner@meduniwien.ac.at
Lackner
E
E
Exler
P S
PS
Fluiter
H C
HC
Kletter
K
K
Tschurlovits
M
M
Dudczak
R
R
Eichler
H-G
HG
Müller
M
M
D000284:Administration, Oral; D000328:Adult; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000097:blood / Q000652:urine; D001682:Biological Availability; D003692:Delayed-Action Preparations; D041981:Gastrointestinal Tract / Q000737:chemistry* / Q000000981:diagnostic imaging; D005772:Gastrointestinal Transit / Q000502:physiology; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy; D008297:Male; D019804:Mesalamine / Q000008:administration & dosage* / Q000097:blood / Q000652:urine; D011877:Radionuclide Imaging; D013607:Tablets / Q000008:administration & dosage
D000894:Anti-Inflammatory Agents, Non-Steroidal; D003692:Delayed-Action Preparations; D013607:Tablets; D019804:Mesalamine