Extrusion: An Enabling Technology for Controlled-Release Hydrophilic Matrix Systems

Abstract

AbstractThis chapter discusses the application of twin-screw hot-melt extrusion as an enabling technology to overcome well-known, physical limitations of hydrophilic controlled-release matrix tablets manufactured by conventional means, such as direct compression and wet and dry granulation. Polymers that are particularly useful in hydrophilic matrix systems that are produced by extrusion include hydroxypropylcellulose, hypromellose, polyethylene oxide, and copovidone. Case studies are presented that show enhanced tablet compactibility, smaller tablets, and greater drug retardation for hydrophilic matrix tablets comprising up to 75 % highly soluble drug (metformin) made by melt extrusion as opposed to conventional methods. In the case of poorly soluble drugs, hot-melt extrusion enables the combination of amorphous drug polymer dispersions and hydrophilic matrix technology in a single manufacturing step, to simultaneously deliver drug over an extended period, enhance equilibrium drug solubility, and prevent the dissolved drug from precipitating out of saturated solution in the simulated GIT fluids for periods as long as 8 h. Twin-screw extrusion is a versatile enabling technology that is increasingly relevant in commercial solid oral dosage form manufacturing.KeywordsDrug ReleaseSolid DispersionPolyvinyl AcetateSoluble DrugMatrix TabletThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.