Degradation of Hylauronic Acid Fillers Using Hyaluronidase in an In Vivo Model.

Soft tissue fillers manufactured with hyaluronic acid (HA) dominate the filler market around the world and the fact that HA can be dissolved using hyaluronidase contributes to its popularity. Degradation of cross-linked HA products can be performed in situ and access to hyaluronidase is therefore essential for health care professionals (HCP) to perform safe filler treatments. The aim of the present study was to develop an in vivo model where hyaluronidase degradation of HA fillers can be studied in a standardized manner and then secondly, to explore the degradation of marketed HA fillers with different product characteristics.Intradermal injections of HA fillers were performed and the injection sites were treated with hyaluronidase. The degradation was evaluated by measuring the heights of the injection site bumps during 5-7 days and with histology at day 7 post injection.The results showed that there was a correlation between the hyaluronidase dose and HA filler degradation. The onset of the degradation was fast for all products and the products were easily degraded.This standardized animal model proved efficient in the study of in vivo degradation of HA fillers using injected hyaluronidase where products manufactured with different technologies were evaluated. J Drugs Dermatol. 2018;17(5):548-553.