Bioavailability enhancement of atazanavir sulphate using mixed micelles: in vitro characterization and in vivo pharmacokinetic study.

This study aims to enhance the oral bioavailability of atazanavir sulphate, a human immunodeficiency virus-1 protease inhibitor known for its poor oral absorption, by formulating mixed micelles using Soluplus® and Kolliphor HS 15. Mixed micelles were prepared through the thin film hydration technique. The micelles were characterized for particle size, polydispersity index (PDI), zeta potential, entrapment efficiency, drug loading, and confirmed for atazanavir sulphate encapsulation via FTIR studies. In vitro release studies were conducted, and the morphology of the micelles was examined using TEM. Atazanavir sulphate mixed micelles exhibited a particle size of 62.92 nm, PDI of 0.221, zeta potential of - 17.8 mV, high entrapment efficiency (99.76 ± 1.06), and drug loading (14 ± 0.82). In vitro release studies demonstrated sustained release up to 12 h, with maximum solubility observed at 2 h under pH 1.2 conditions. TEM analysis revealed spherical micelle morphology. Oral administration of atazanavir sulphate mixed micelles showed a 1.23-fold increase in relative bioavailability compared to pure drug suspension. The formulation of mixed micelles using Soluplus® and Kolliphor HS 15 offers a promising strategy to improve the oral bioavailability of atazanavir sulphate. These findings suggest the potential utility of mixed micelles as an effective delivery system for atazanavir sulphate, offering enhanced therapeutic outcomes for patients.