Nano Cocrystals: Crystal Engineering from a Nanotechnological Perspective

The pharmaceutical industry has been continuously in search of economical and scalable strategies to overcome the biopharmaceutical limitations associated with Active Pharmaceutical Ingredients (API), such as low aqueous solubility, bioavailability, stability, and short half-life in biological systems [1-5]. According to an estimate, about 40% [6] of the drug products in the market and about 70% [6-8] of drug candidates in research and development process are reported to have solubility issues. As a result, out of the many molecules initially discovered, only a few make it to the formulation stage. Hence, the issue of poor drug solubility, dissolution, absorption, and improving the efficiency of the delivery of the drug to the target site remains the key challenges in pharmaceutical research and development [9]. Pharmaceutical researchers over Low aqueous solubility and poor bioavailability are the major hurdles during drug development for the oral route. A large number of the newly discovered drug molecules fall under the BCS II class and have solubility related issues and hence pose low oral bioavailability, which, in turn, render them non-suitable candidates for further development. A multitude of solubility enhancement approaches are available. Notable among them are salt formation, solid dispersions, inclusion complexes, cocrystallization, nanonization, etc. Cocrystallization and nanonization are among the most widely used approaches in the pharmaceutical field that offer multiple enhancements to the active pharmaceutical ingredients. This review endeavours to cover the recent work, important findings, advantages offered by nano-sized cocrystals, future aspects and challenges in the implementation of this newer approach in pharmaceutical research and development.