MUCOADHESIVE MICROSPHERES CONTAINING AMOXICILLIN FOR CLEARANCE OF HELICOBACTER-PYLORI

In an effort to augment the anti-Helicobacter pylori effect of amoxici llin, mucoadhesive microspheres, which have the ability to reside in t he gastrointestinal tract for an extended period, were prepared. The m icrospheres contained the antimicrobial agent and an adhesive polymer (carboxyvinyl polymer) powder dispersed in waxy hydrogenated castor ai l, The percentage of amoxicillin remaining in the stomach both 2 and 4 h after oral administration of the mucoadhesive microspheres to h Mon golian gerbils under fed conditions was about three times higher than that after administration in the form of a 0.5% methylcellulose suspen sion. The in vivo clearance of EI, pylori following oral administratio n of the mucoadhesive microspheres and the 0.5% methylcellulose suspen sion to infected Mongolian gerbils was examined under fed conditions. The mucoadhesive microspheres and the 0.5% methylcellulose suspension both showed anti-H, pylori effects in this experimental model of infec tion, but the required dose of amoxicillin was effectively reduced by a factor of 10 when the mucoadhesive microspheres were used, In conclu sion, the mucoadhesive microspheres more effectively cleared ii. pylor i from the gastrointestinal tract than the 0.5% methylcellulose suspen sion due to the prolonged gastrointestinal residence time resulting fr om mucoadhesion, A dosage form consisting of mucoadhesive microspheres containing an appropriate antimicrobial agent should be useful for th e eradication of fi, pylori.