Abstract

PHARMACEUTICAL CO-CRYSTALS: AN OVERVIEW

Anuja S.*, Viresh K.C., Abdul Raheem T. and Shabaraya A.R.

ABSTRACT

Poor aqueous solubility and low oral bioavailability of an active pharmaceutical ingredient are the limitations during the growth of a new product. Co-crystal formation is a new approach to enhance the physicochemical properties of the active pharmaceutical ingredient. Co-crystallization with pharmaceutically acceptable compounds does not affect the pharmacological activity of the API but can improve the physical properties like solubility, stability and dissolution rate. Co-crystals are multi-component system of active pharmaceutical ingredient with a stoichiometric amount of a pharmaceutically acceptable coformer included within the crystal lattice. By manufacturing pharmaceutical co-crystals, the physicochemical properties of a drug can be improved thus it offers a great opportunity for the development of new drug products in the pharmaceutical industry. Most significantly, co-crystals can create new medicines with increased solubility and hence improve the efficiency and safety of the treatment. The main factor which affects co-crystal preparation is its thermodynamic stability. Screening of co-crystals gives details about the chemical structure and relation between active pharmaceutical ingredient and coformer. This review covers the different methods used for the synthesis of co-crystal such as grinding, slurrying, antisolvent, hot-melt extrusion, spray drying, etc. A brief description of characterization techniques routinely used for co-crystals and also its pharmaceutical applications has been incorporated here. Reported works on co-crystals were reviewed and have been briefly outlined here which further help to understand the concept of co-crystals in depth.

Keywords: Pharmaceutical co-crystals, co-crystallization, Dissolution rate, solubility, stability, solvent evaporation.