Confined crystallization of drug in directionally freeze-dried water-soluble template

The applicability of confined crystallization is limited by the use of extra template materials unsuitable for oral dosage forms. In consideration of this limitation, mannitol was processed into a template with well controlled pores. This template was used for the subsequent confined crystallization of a model drug, resulting in drug/mannitol composite powders processable into the common operations of oral solid dosage forms. The confined crystallization produced a significant melting point depression, caused by a significant particle size reduction, but did not alter the crystal polymorphism. The in vitro release of drug was significantly improved by the confined crystallization.