Transferring Crystallization Conditions from Small to Larger Scale for Achieving Targeted Crystal Morphologies of an Active Pharmaceutical Ingredient

Abstract

Crystal morphology plays a critical role in the processability and physicochemical behavior of active pharmaceutical ingredients. Manipulating crystal morphology involves consideration of crystallization conditions such as temperature, supersaturation, and solvent choice. Typically, experimental screenings on a small scale are conducted to find targeted crystal morphologies. However, results from such small-scale experiments do not assure direct success at a larger scale, particularly if the small-scale setup differs significantly from a conventional stirred crystallizator. In this study, we successfully validated the morphologies observed in the small-scale experiments of an exemplary API, Bitopertin, when scaled up by a factor of 200, through the maintenance of identical process conditions and geometrical vessel relations. This successful scalability highlights the significant potential of small-scale crystallization studies to provide a reliable foundation for further exploration in large-scale endeavors.