Proliposome-based transdermal delivery of levonorgestrel

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Dermatology

Background:

• Transdermal drug delivery offers a non-invasive route for systemic drug administration.
• Levonorgestrel, a hydrophobic drug, presents challenges for effective transdermal delivery.
• Proliposomal systems are investigated as advanced formulations for enhanced drug permeation.

Purpose of the Study:

• To develop and evaluate a mesophasic proliposomal system for transdermal levonorgestrel delivery.
• To investigate the in vitro and in vivo performance of the developed proliposomal system.
• To compare the efficacy of the proliposomal system with a conventional polyethylene glycol (PEG)-based ointment.

Main Methods:

• Formulation of a mesophasic proliposomal system containing levonorgestrel.
• In vitro characterization of vesicle morphology (unilamellar/multilamellar) and drug release kinetics (zero order).
• In vivo evaluation in animal models to assess transdermal flux, lag phase, and therapeutic levels, with comparison to a PEG-based ointment control.

Main Results:

• The proliposomal system exhibited mostly unilamellar vesicles with spontaneous budding upon hydration.
• Drug release followed zero-order kinetics, indicating sustained release.
• Transdermal flux was highest with alcohols, followed by lemon oil. In vivo studies revealed a lag phase, necessitating a loading dose.
• The proliposomal system demonstrated superior performance compared to the PEG-based ointment.

Conclusions:

• The developed mesophasic proliposomal system is a viable and efficacious platform for transdermal delivery of hydrophobic drugs like levonorgestrel.
• The system offers advantages over conventional topical formulations, suggesting potential for improved therapeutic outcomes.
• Further optimization, including loading dose strategies, may enhance clinical applicability.