Amorphous cyclosporin A nanoparticles for enhanced dermal bioavailability.

Area of Science:

• Pharmaceutical Sciences
• Dermatology
• Nanotechnology

Background:

• Cyclosporin A (CyA) is a potent immunosuppressant used for conditions like psoriasis.
• Improving the dermal penetration of CyA is crucial for effective topical treatment.
• Current formulations may have limitations in delivering CyA efficiently to the skin.

Purpose of the Study:

• To formulate amorphous Cyclosporin A (CyA) nanoparticles for enhanced dermal delivery.
• To evaluate the physical stability and drug content of the CyA nanoparticle suspension.
• To compare the dermal penetration of CyA nanoparticles versus micro-sized CyA particles.

Main Methods:

• Formulation of amorphous CyA nanoparticles using bead milling with TPGS (Kolliphor TPGS) as a stabilizer.
• Characterization of nanoparticle size (bulk and laser diffraction) and physical stability over one year.
• Incorporation of nanoparticles and micro-sized CyA into hydroxypropylcellulose (HPC) gels for skin penetration studies.
• Assessment of dermal penetration using the tape stripping method on pig ear skin.

Main Results:

• Stable amorphous CyA nanoparticle suspension (350 nm bulk diameter) with minimal drug loss (5%) over one year.
• CyA nanoparticles demonstrated significantly higher dermal penetration (6.3-fold increase) compared to micro-sized CyA particles.
• Penetrated cumulative CyA amount from nanoparticles reached 450.1 μg/cm(2) versus 71.3 μg/cm(2) for micro-sized particles at tape 30.

Conclusions:

• Amorphous CyA nanoparticles formulated with TPGS are physically stable and feasible for commercialization.
• The nanoparticle formulation dramatically enhances CyA dermal penetration, offering a promising approach for topical delivery.
• This technology holds potential for developing improved dermal formulations for CyA in treating skin conditions like psoriasis.