title: Preformulation considerations for controlled release dosage forms. Part I. Selecting candidates.
abstract: The physical-chemical properties of interest for controlled release (CR) dosage form development presented are based on the author's experience. Part I addresses selection of the final form based on a logical progression of physical-chemical properties evaluation of candidate forms and elimination of forms with undesirable properties from further evaluation in order to simplify final form selection. Several candidate forms which could include salt, free base or acid, polymorphic and amorphic forms of a new chemical entity (NCE) or existing drug substance (DS) are prepared and evaluated for critical properties in a scheme relevant to manufacturing processes, predictive of problems, requiring small amounts of test materials and simple analytical tools. A stability indicating assay is not needed to initiate the evaluation. This process is applicable to CR and immediate release (IR) dosage form development. The critical properties evaluated are melting, crystallinity, solubilities in water, 0.1 N HCl, and SIF, hygrodymamics, i.e., moisture sorption and loss at extremes of RH, and LOD at typical wet granulation drying conditions, and processability, i.e., corrosivity, and filming and/or sticking upon compression.
authors.affiliation: FA Chrzanowski, Inc., Marlton, New Jersey 08053-1320, USA. frankchrzan@comcast.net
authors.forename: Frank
authors.initials: F
authors.lastname: Chrzanowski
mesh_terms: D000928:Antidepressive Agents / Q000737:chemistry; D002626:Chemistry, Pharmaceutical; D003460:Crystallization; D003692:Delayed-Action Preparations; D004355:Drug Stability; D006813:Humidity; D006851:Hydrochloric Acid / Q000737:chemistry; D007546:Isoquinolines / Q000737:chemistry; D008128:Logic; D044367:Phase Transition; D011758:Pyrroles / Q000737:chemistry; D012995:Solubility; D013678:Technology, Pharmaceutical / Q000379:methods*; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D000928:Antidepressive Agents; D003692:Delayed-Action Preparations; D007546:Isoquinolines; D011758:Pyrroles; D014867:Water; C049926:McN 5707; D006851:Hydrochloric Acid