Inclusion complex of erlotinib with sulfobutyl ether-β-cyclodextrin: Preparation, characterization, in silico, in vitro and in vivo evaluation

Abstract

The aim of the study was to investigate the impact of erlotinib sulfobutyl ether beta-cyclodextrin complex (ERL-SBE-β-CD) on ERL dissolution rate and oral bioavailability. Preliminary comparative phase solubility study indicated ERL exhibited maximum solubility in SBE-β-CD solution. Optimal experimental design confirmed freeze drying of SBE-β-CD:ERL in 1:1.05 molar ratio as the optimum method. Differential scanning calorimetry (DSC), Fourier transformation infrared spectroscopy (FT-IR), powder X-ray diffractometry (PXRD), proton nuclear magnetic resonance (1H NMR) and two-dimensional rotating-frame Overhauser effect spectroscopy (2D ROESY NMR) confirmed the inclusion complexation. The in silico computational study, employed to analyze the comparative interactions of ERL with SBE-β-CD and β-CD, indicated ease of ERL-SBE-β-CD complexation. In vitro dissolution and in vivo bioavailability studies further confirmed the ERL-SBE-β-CD as a valuable approach to enhance ERL oral bioavailability with 3.6-fold increase in relative oral bioavailability with higher Cmax (134.29±36.51 vs. 42.36±1.75μg/ml) and AUC0–∞ (2103.47±156.75 vs.580.43±71.91μg/mlh) over the free drug. The complex exhibited 3.2-fold increase in Cmax with 5.4-fold decrease in Tmax (0.5±0.2 vs. 2.7±0.8h) in comparison to pure ERL. Thus, ERL-SBE-β-CD complexation exhibits a potential to enhance oral bioavailability of ERL leading to reduce dose and dose-related side effects.