Drug–Drug Coamorphous System of Tadalafil and Finasteride for Enhanced Pharmaceutical Performance

The study explores a coamorphous system combining tadalafil (TDF) and finasteride (FNS) in a 1:1 molar ratio to enhance pharmaceutical performance, particularly for treating benign prostatic hyperplasia. Both drugs individually have low aqueous solubility, but the coamorphous system, created through mechanochemical synthesis, shows improved solubility and dissolution rates. Characterization techniques such as powder X-ray diffraction and FT-IR spectroscopy confirmed the formation of the coamorphous phase, with computational studies supporting the intermolecular interactions. In vitro and in vivo studies demonstrated significant improvements in dissolution and bioavailability compared to the physical mixture. The coamorphous system also exhibited reasonable physical stability under various conditions, suggesting its potential as a superior therapeutic alternative to the marketed physical mixture.