Background: Transfersome is a drug delivery technology based on highly deformable, ultraflexible lipid vesicles which penetrate the skin when applied non-occlusively.
Objectives: To assess the advantages of this carrier-based formulation in humans, the efficacy and the atrophogenic potential of triamcinolone acetonide (TAC) in Transfersome was compared with commercially available TAC-containing cream and ointment.
Methods: Healthy volunteers were enrolled in double-blind, placebo-controlled clinical trials with random study medication assignment to the test areas.
Results: A 10-fold lower dose of TAC in Transfersome(R) (2.5 micro g cm-2) was bioequivalent to 25 micro g cm-2 TAC in conventional formulations as measured by erythema suppression (cream: P = 0.01, ointment: P < 0.001). A skin blanching assay revealed different kinetics of the formulations, with a delayed onset of action of the Transfersome and ointment preparations. Ultrasonic measurements revealed a significantly reduced atrophogenic potential. There was a 12.1% reduction in skin thickness given by TAC in Transfersome compared with a 21.1% reduction given by a bioequivalent dose in TAC cream after a 6-week treatment period (P = 0.007).
Conclusions: Transfersome may significantly improve the risk-benefit ratio of topically applied glucocorticosteroids.