Preparation, solid state characterization of etraverine co-crystals with improved solubility

This study establishes that etraverine, an anti human immuno deficiency virus drug, is produced as cocrystals to improve the solubility of the same by cocrystallisation methods and characterization of the cocrystals formed. Etraverine belongs to the class IV category as per the Biopharmaceutical Classification System which are basically classified as a drug with low solubility and low permeability. Pharmaceutical cocrystals are structurally homogeneous crystalline materials containing an API and the conformer in definite stoichiometric amounts. Etraverine formed physicochemically stable cocrystal with tartaric acid when prepared in 1:1 molar ratio by slurry method.The formation of the cocrystals was confirmed by analytical techniques such as X-ray diffraction, differencial scaning calorimetry and Fourier transform infrared spectroscopy. The dynamic solubility of etraverine in the cocrystal of ratio 1:1 was improved by approximately 3.6 fold as compared to pure etaverine. The percentage of drug release at 180 min was also four times higher for etraverine cocrystal of ratio 1:1 as compared to pure etraverine. This study demonstrates the capability of co-crystalization technique to improve the solubility of etraverine.