The Influence of Amorphous Solid Dispersions with a Grafted Copolymer of Polyvinylcaprolactam, Polyvinyl Acetate, and Polyethylene Glycol on the Crystallinity and Dissolution Kinetics of N-Butyl-N-methyl-1-phenylpyrrolo[1,2-a]pyrazine-3-carboxamide

Poor water solubility, which negatively influences the bioavailability of oral medications, is typical for the vast majority of molecules (up to 70%) developed as active pharmaceutical ingredients (API). Amorphous solid dispersions of N-butyl-N-methyl-1-phenylpyrrolo[1,2-a]pyrazine-3-carboxamide (GML-3) with a Soluplus® polymer are developed in this study. The inclusion of GML-3, which is almost insoluble in water and has antidepressant and anxiolytic action, in the solid dispersions makes it possible to convert it from a crystalline to an amorphous state. The amorphous state of the solid dispersions is confirmed by X-ray phase analysis and differential scanning calorimetry. The interaction between the polymer and GML-3 inside the dispersions is revealed. It is possible to achieve 98.4% solubility of GML-3 in water via the preparation of GML-3 solid dispersions with Soluplus®, which solves the problem of solubility of this API.