THE EFFECT OF PROCESSING VARIABLES ON THE COMPRESSION PROPERTIES OF CONTROLLED-RELEASE CORE-IN-CUP COMPRESSED TABLETS FROM A NEW ADJUSTABLEPUNCH

A novel adjustable punch that can be adjusted to produce compressed cu p-shape tablets of different depth has been evaluated. The resultant c ups have been compressed together with core tablets to produce compres sion coated tablets that have the ability to release active drug at a zero-order rate. The influence of three independent variables (percent age carnauba wax in the cup tablet, the compressed hardness of the cup tablet, and depth of the cup tablet) on the friability of the cup tab let and splitting of the cup tablet in aqueous dissolution fluid was s tudied using a 3(3) factorial design. The friability of the cup tablet s were influenced by all the factors as well as the second-order inter action effects. The splitting of the cup tablets were only significant ly influenced by the depth of the cup tablet and the hardness of the c up tablets. Core-in-cup tablets containing 5% w/w HPMC K4M in ibuprofe n as the core, 4 mm final cup depth, 15% carnauba wax in ethylcellulos e as the cup, and compressed to a cup hardness of approx. 100 N/m(2) a nd final core-in-cup hardness of approx. 160 N/m(2), released ibuprofe n at zero-order rate of release for up to 18 h.