Invasomes: Vesicles for Enhanced Skin Delivery of Drugs

The document from 2016 examines invasomes, a type of vesicle that enhances drug delivery through the skin. Invasomes are composed of unsaturated soybean phosphatidylcholine, ethanol, and terpenes such as cineole, citral, and d-limonene, which increase the fluidity and deformability of the vesicles, aiding in the disruption of the skin's stratum corneum (SC) to facilitate drug penetration. Studies indicated that invasomes deliver higher amounts of drugs like cyclosporine A (CsA) and temoporfin (mTHPC) into deeper skin layers than conventional liposomes and solutions. Invasomes with 1% w/v terpene mixtures, particularly citral, were most effective in delivering mTHPC into the skin. They also enhanced the penetration of both lipophilic and hydrophilic substances and showed promise in topical treatments for conditions like alopecia areata by inducing faster hair regrowth. While invasomes did not reduce tumor size in a pilot study with mice, they were effective in reducing the survival of A431 skin cancer cells in photodynamic therapy (PDT), with a survival rate of about 16% after treatment. The document concludes that invasomes are an efficient delivery system for drugs, with potential for further optimization by exploring different terpenes and mixtures for more effective skin delivery.