Cocrystallization for successful drug delivery.

INTRODUCTION: Cocrystallization is an effective crystal engineering approach for modifying the crystal structure and properties of drugs. The number of examples of solving drug formulation and manufacture problems by cocrystallization is rapidly growing. An updated review that systematically examines the cocrystal research in the context of drug delivery is timely and valuable. AREAS COVERED: Topics covered in this review include nature of cocrystal, impact of cocrystallization on key pharmaceutical properties (both enhancement and deterioration), cocrystal preparation method and future directions in this field. The focus of this review is on the crystal engineering and pharmaceutical literature in the last 5 years. However, classical literature is also examined when relevant. EXPERT OPINION: The most effective cocrystal research relies on both in-depth understanding of structure-property relationship and efficient preparation of desired cocrystals. The future cocrystal research will see growth in the areas of designing ternary and higher-order structures, cocrystals between neutral and ionic species, cocrystal polymorphism, cocrystal glasses and thermodynamics of cocrystallization.