Crystal engineering technique has been widely explored in recent times to bring about changes in crystallinity which aids to achieve various goals such as solubility enhancement, stability and in vivo bioavailability without altering the chemical properties of the drug. Cocrystallisation is one of the crystal engineering approaches where the drug and an inert coformer are linked together by hydrogen bonding forming supramolecular homosynthon or heterosynthon using solvent-based or solvent-free techniques. Processing of active pharmaceutical ingredients with inert water-soluble coformers yields multicomponent crystalline cocrystals with high-performance characteristics and enhanced flow properties. Due to the emerging need of the industry for greener techniques, hot melt extrusion (HME), a continuous and solvent-free process is emerging as a field of interest in the mechanochemical synthesis of various pharmaceutical dosage forms such as solid dispersions, implants, ointments, and cocrystals. The current review emphasizes the role of HME as a cocrystallization technique for drugs to tailor-make their properties and ease of formulation. The distinct feature of HME is phase control during the process of cocrystallization. Furthermore, the selection of appropriate coformers with desirable water-solubility and stability features makes HME amenable to cocrystallization of versatile actives yielding suitable dosage forms. The application of process analytical technology further adds ease of monitoring during HME in cocrystallization approaches. Due to these salient features of HME, it can act as a prospective technique for cocrystallization of versatile drugs thus yielding dosage forms with desirable solubility and stability features.

Objective: The objective of the current study was to explore top down methods of size reduction like high speed homogenisation and media milling in synergism with spray drying in amorphization and solubility enhancement of BCS Class II antilipidemic drug Simvastatin USP. Methods: Spray-dried micronized simvastatin USP was formulated by homogenisation and media milling of drug suspension in optimized stabilizer solution. Stabilizer combination, duration of homogenisation and ball milling and drug: stabilizer ratio was optimized. The obtained dispersion was transformed into solid powder using spray drying. The obtained Spray-dried micronized Simvastatin USP was evaluated for visual morphology, Infrared spectroscopy, Differential scanning calorimetry, in vitro drug release studies, X-Ray diffractometry, Scanning electron microscopy, contact angle measurement, solubility studies, dispersibility studies and intrinsic dissolution rate testing. Results: Spray-dried micronized simvastatin USP was found to show amorphization of crystalline Simvastatin USP as confirmed by the absence of drug peak in Differential scanning calorimetry and lowered signal intensity in X-Ray diffraction studies. Spray-dried micronized Simvastatin USP was found to show enhanced drug hydrophilicity and solubility as confirmed by lowering in contact angle and increase in solubility and ease of dispersibility observations. In vitro dissolution testing and intrinsic dissolution rate testing were found to show an increase in drug release from 11% to 79% and 4 mg min-1 cm-2 to 17 mg min-1 cm-2 for drug and Spray-dried micronized Simvastatin USP respectively. Conclusion: Media milling in synergism with spray-drying was found to be a prospective solubility enhancement technique for poorly-soluble Simvastatin USP.