DEVELOPMENT OF A ZERO-ORDER RELEASE ORAL COMPRESSED TABLET WITH POTENTIAL FOR COMMERCIAL TABLETTING PRODUCTION

The release of caffeine and ibuprofen as model drugs from a unique core-in-cup oral drug delivery system has been examined to determine their time exponent (t(n)) vs release profiles. The core-in-cup drug delivery system consisted of cores of various concentrations of two grades of hydroxypropylmethylcellulose (HPMC). HPMC K4M and HPMC K15M were used as the polymers in the core matrix. The flat disc-shaped core Tvas then compressed with a previously compressed cup-shape tablet consisting of inert and impermeable carnauba wax and ethylcellulose. These drug delivery systems released active drug at a zero-order rate for periods of time between 8 and 23 h. The release rate was then compared to core only systems. The t(n) exponents varied from 0.477 for the lowest core system to 0.997 for a 5% w/w HPMC K4M in ibuprofen core-in-cup system. Because the core, the cup, and the core-in-cup are compressed on an automated tabletting press, this drug delivery system can be easily scaled up to commercial production.