BICONCAVE COATED, CENTRALLY PERFORATED TABLETS FOR ORAL CONTROLLED DRUG-DELIVERY

A new approach to achieve sustained and controlled delivery of bioactive agents via the oral route is demonstrated for directly compressible, biconcave tablets that are coated with an impermeable coat except for their central releasing hole. The cores of these tablets dissolve radially, starting from the cylindrical releasing area and release the model drug, metoprolol tartrate, at nearly constant rate. The release kinetics were found to be significantly influenced by excipient levels, drug load, and hole size. Results obtained from in-vitro dissolution testing demonstrated that these biconcave devices could, potentially, be used to deliver drugs, orally, for up to once-a-day dosing at controllable rates.