Tamoxifen in topical liposomes: development, characterization and in-vitro evaluation

Area of Science:

• Pharmaceutics
• Dermatology
• Drug Delivery Systems

Background:

• Tamoxifen, an anti-estrogen, shows promise for treating skin disorders.
• Topical formulations are desired to avoid systemic side effects of oral tamoxifen.
• Liposomal carriers offer potential for enhanced topical delivery and skin retention.

Purpose of the Study:

• To prepare and characterize tamoxifen-loaded liposomal systems.
• To compare the topical performance of liposomal tamoxifen with non-liposomal formulations.
• To evaluate the potential of liposomes for localized delivery of tamoxifen in skin.

Main Methods:

• Multilamellar liposomes prepared using the thin film hydration method.
• Formulation and process parameters optimized for desired liposome attributes.
• Characterization included morphology, size (Malvern mastersizer), and stability studies.
• In-vitro skin permeation studies conducted using mice skin, comparing with solution and gel formulations.

Main Results:

• Optimized liposomes were multilamellar, homogenous, with a mean vesicle diameter of 5.3 microm.
• Maximum tamoxifen loading achieved was 57.5% with specific lipid compositions.
• Liposomes stored at 2-8°C showed high stability (5% drug loss over 5 weeks).
• Significantly higher skin permeation and retention of tamoxifen observed with liposomal formulations compared to controls.

Conclusions:

• Tamoxifen can be successfully entrapped in liposomes with good loading and vesicle characteristics.
• Liposomal tamoxifen demonstrates enhanced skin permeation and retention, suggesting facilitated entry into the stratum corneum.
• These findings support the use of liposomal tamoxifen for improved, localized drug action in treating skin disorders.