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Published on: July 30, 2020
Cyclosporin pro-dispersion liposphere formulation
Avi Avramoff1, Wahid Khan, Aviva Ezra
1Department of Medicinal Chemistry, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel.
Summary
A novel oral pro-dispersion liposphere formulation was developed for cyclosporin A (CsA), a poorly soluble drug. This formulation demonstrates potential for enhancing the bioavailability of water-insoluble drugs.
Area of Science:
- Pharmaceutical Sciences
- Drug Delivery Systems
- Biopharmaceutics
Background:
- Cyclosporin A (CsA) is a water-insoluble drug with limited oral bioavailability.
- Effective drug delivery systems are crucial for improving the therapeutic efficacy of such compounds.
Purpose of the Study:
- To prepare and characterize an oral pro-dispersion liposphere formulation for CsA.
- To evaluate the potential of this formulation for enhancing the bioavailability of water-insoluble drugs.
Main Methods:
- Formulation of CsA pro-dispersion lipospheres using solid fat, dispersing agents, and amphiphilic solvents.
- Characterization using particle size analysis, in vitro release studies, ultracentrifugation, TEM, Cryo-TEM, and DSC.
- Comparison with the marketed Neoral® microemulsion formulation.
Main Results:
- Optimized liposphere formulations were successfully prepared and confirmed to form solid liposphere particles upon dispersion in water.
- Particle size was influenced by solid fat type and amphiphilic solvent.
- The formulation exhibited stability for 2 years under normal storage conditions.
Conclusions:
- The developed pro-dispersion liposphere formulation is a homogeneous solution that spontaneously forms dispersions in aqueous media.
- This formulation strategy holds promise for improving the oral bioavailability of water-insoluble drugs like CsA.
- The formulation offers a potential clinical application for challenging drug compounds.
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