Spring and parachute: How cocrystals enhance solubility

This article is intended to combine literature on cocrystallization - a tool for enhancing the solubility and for improving the physicochemical properties of an API (an API is the molecule which is responsible for providing the therapeutic effect) with special emphasis on the mechanism responsible for the same. The pharmaceutical industries are witnessing a developing crisis in the process of drug development due to the increasing cost of their R&D departments, the failure of some blockbuster drug candidates exhibiting poor aqueous solubility and the unavailability of newer molecules because of patent limitations. Cocrystallization is an emerging approach to improve solubility, dissolution profile, bioavailability, and other physicochemical and mechanical properties of an API. A pharmaceutical cocrystal is now a new epitome which enables the use of a wide range of active pharmaceutical ingredients without the need to form or break the covalent bonds. The prime focus of this review article is the mechanism on how cocrystals have a solubility advantage over the amorphous form. This review also provides a brief introduction to the nature of cocrystals, their role, principles of crystal engineering and also highlights the nature of supramolecular synthons which are present in cocrystals. (C) 2016 Elsevier Ltd. All rights reserved.