Application Driven Methodology for Development of Communicating Systems

PCT No. PCT/HU84/00006 Sec. 371 Date Aug. 27, 1984 Sec. 102(e) Date Aug. 27, 1984 PCT Filed Jan. 25, 1984 PCT Pub. No. WO84/02843 PCT Pub. Date Aug. 2, 1984.The invention relates to a process for the preparation of sustained release solid pharmaceutical compositions having an active ingredient content of at least 80% and possessing a structure which loosens in aqueous medium but does not disintegrate to discrete particles within 4 hours which comprises coating the particles of the active ingredient in a liquid medium with a water insoluble polymer-preferably with an ethyl cellulose polymer film-and thereafter admixing the coated crystals with at least one disintegrating agent being capable of swelling in aqueous medium and other auxiliary agents conventionally used in pharmaceutical industry and pressing the mixture into tablets. The advantage of the process of the present invention is that it is readily feasible with a very wide range of active ingredients and provides sustained release tablets having a high active ingredient content.