Design and Optimization of Inclusion Complexes Using QbD Principles: A strategy to enhance solubility and dissolution of Voriconazole

Purpose: This current study aimed to increase the solubility and dissolution of poor aqueous soluble drug voriconazole (VC), a lipophilic antifungal drug, through the inclusion complexes with β-cyclodextrin (β-CD) by a solvent-free technology like co-grinding method. Methods: By using RSM (Response Surface Methodology), a CCD (central composite design) was utilized to analyse the impact of β-CD amount and grinding time on VC solubility and % CDR (percentage cumulative drug release). Results: Phase solubility studies confirmed the formation of an A _L -type complex. Statistical analysis revealed that both factors significantly and positively affected the responses. The optimized formulation, comprising 600 mg of β-CD and a grinding time of 30 minutes, exhibited a substantial increase in solubility (70.64 mg/ml) and achieved a high dissolution rate (98.47%) with a desirability value of 0.969. The formation of the inclusion complex was further validated through comprehensive characterization studies. FTIR spectra showed minor shifts in characteristic VC peaks. DSC thermograms revealed the disappearance of the characteristic sharp melting endotherm of VC in the optimized complex, suggesting molecular dispersion within β-CD. XRD patterns revealed a significant reduction in VC crystallinity. SEM images display a distinct morphological change from crystalline VC to smooth-surfaced complex particles. Conclusion: These findings demonstrate that VC/β-CD inclusion complex is a promising approach to significantly increase the aqueous solubility and dissolution of voriconazole, potentially enhancing its therapeutic efficacy.