| abstract |
The invention relates to a microparticulate delayed release system. control of active ingredients (AP) whose absorption window in vivo is essentially limited to the upper parts of the gastrointestinal tract, this system being intended for oral administration. The goal of the invention is to provide a system ensuring the release of the fascia PA certain thanks to a double release mechanism "time dependent" and "pH dependent. "To achieve this goal, the invention provides a dosage form multimicrocapsular oral designed so that its effectiveness therapeutic is guaranteed, and in which the release of the AP is governed by a double release triggering mechanism: "triggering time" and "triggering pH" This system is made up of microcapsules (200 to 600 ~ m) comprising a PA core covered with a coating film (maximum 40% in weight) comprising a hydrophilic polymer A (Eudragit® L) and a compound B hydrophobic (vegetable wax melting temperature = 40-90 ~ C), with B / A included between 0.2 and 1.5. These microcapsules have a dissolution behavior in in vitro as at constant pH 1.4, there is a lag phase between 1 and 5 hours followed by release of the AP and such as the change from pH 1.4 to pH 6.8 causes a release of the AP without latency time in vitro. |