Preclinical Development – Chemical
2019 PharmSci 360
Transdermal hormonal therapy (THT) delivers the exogenous hormones into to the systemic circulation via skin. The transdermal hormonal products are available in patch where other formulations such is cream, gel or spray is directly applied on the skin. It has been reported that residual hormones on the skin have the potential of transfer to healthy individuals via skin contact. The skin-to-skin transfer of hormonal drug may cause hormonal imbalance and adverse effects. The risk of skin-to-skin transfer can be only evaluated by the clinical PK studies. Currently, there is no in vitro methodology identified for assessing this risk. Therefore, current study aimed at developing a novel in vitro permeation methodology to evaluate the skin-to-skin drug transfer by using vertical diffusion cell and human cadaver dermatomed skin. The study results demonstrated that the amount of hormone recovered from dosed skin increased by increasing the residence time of the gel on the skin surface. The extent of drug transfer and permeation from the dosed to naïve skin samples was directly proportional to the amount of drug retained by the dosed skin. Therefore, this study provided a novel in vitro method that may be use in predicting the risk of skin-to-skin drug transfer during THT.