Abstract

Co-crystal is an attractive alternative and a new class of solid forms because that can be engineered to have desired physicochemical properties. Co-crystals have gained considerable attention from the generic pharmaceutical industry after the USFDA released its finalized guidlines in the year 2018 on the regulatory classification of co-crystals. In this review, we discussed how co-crystals could be explored as a potential alternative solid form for the development of a generic product that meets the legal, regulatory, and bioequivalence requirements. In the contents, we discussed in detail concepts such as the selection of coformers, various ways of making co-crystals, the strategy of characterization to discriminate between co-crystal and salt, polymorphism in co-crystals, the aspects of intellectual property and, finally, the regulatory aspects of co-crystals.

Keywords: Co-crystals, crystal engineering, generic pharmaceuticals, solid oral dosage form, regulatory perspective, polymorphism, solubility.

Graphical Abstract