Design and evaluation of a new central core matrix tablet

In this paper, a study of the influence that two formulation variables exert on the drug release process from a new controlled drug delivery system has been realized in order to obtain a constant release rate during a prolonged period of time, and a programmed drug release. The drug release profiles obtained for the different batches have shown an interesting relationship between the particle size of the channeling agent used and the length of the zero-order periods. Furthermore, it is possible to modify the lag-times by using different granulometric fractions of the channeling agent. Similar results have been obtained by changing the weight of the assayed tablets. (C) 1997 Elsevier Science B.V.