Entwicklung eines biorelevanten Freisetzungstestgerätes zur Simulation mechanischer Stressfaktoren bei der Magen Darm Passage von Arzneiformen Kontrollierte Wirkstofffreisetzung Wirkstofffreisetzung Gastrointestinaltrakt Dissolution Six Solutions biorelevanter Freisetzungstest prädiktive Freisetzungstests dose dumping biorelevanter mechanischer Stress The prediction of the in vivo drug release characteristics of modified release (MR) oral dosage forms by in vitro dissolution tests is a prerequisite for successful product development. In order to improve the predictive power of dissolution testing we developed a novel dissolution test apparatus that simulates physical conditions of the gastrointestinal passage of MR dosage forms. The simulation includes pressure force exerted by gastrointestinal (GI) motility shear stress force generated during phases of GI transport and intermittent contact with intestinal fluids while the dosage form is located in an intestinal air pocket. The novel apparatus was evaluated using extended release (ER) tablets of nifedipine and diclofenac. The dissolution characteristics of some of the tested products were strongly dependent on the test conditions and could be distinctly influenced by the mechanical stress events of biorelevant intensity. The results obtained so far indicate that the mechanical robustness of the formulation may be an essential factor determining the drug delivery characteristics of MR formulations ...