Charles University, Faculty of Pharmacy in Hradec Králové, Akademika Heyrovského 1203, 500 05 Hradec Králové, Czech Republic.
GSK Consumer Healthcare s.r.o, Hvězdova 1734/2c, 140 00 Praha 4, Czech Republic.
J Pharm Sci. 2021 Jun;110(6):2517-2523. doi: 10.1016/j.xphs.2021.01.022. Epub 2021 Jan 26.
Topical pain relief products differ in the type of drug, concentration, and formulation. All these factors influence the drug transit through the skin barrier, and its eventual retention in the skin as a reservoir for subsequent release. In addition, the drug potency can be different, which is important for the product efficacy. We studied here ex vivo human skin permeation and retention of five over-the-counter NSAID gels containing 2.32% diclofenac (DIC) and 5-10% etofenamate (ETF). The potency of the permeated/retained drug amounts were compared using a composite parameter, the Index of Relative Topical Anti-inflammatory Activity (IRTAA), which is calculated as the product of the skin permeation/retention and the drug relative potency. The IRTAAs of the DIC gel were 94-667-fold higher and 72-208-fold higher for transdermal delivery and skin retention, respectively, than IRTAAs of the ETF gels. These superior IRTAAs indicate that DIC delivered by this topical formulation would achieve a higher bioactivity and would form a potent drug reservoir relevant for its subsequent long-lasting release.
局部止痛产品在药物类型、浓度和制剂方面存在差异。所有这些因素都会影响药物穿过皮肤屏障的转运，并最终在皮肤中作为储存库保留下来，以便随后释放。此外，药物效力可能不同，这对于产品疗效很重要。我们在这里研究了含有 2.32%双氯芬酸（DIC）和 5-10%依托芬那酯（ETF）的五种非处方 NSAID 凝胶在人体皮肤中的渗透和滞留情况。使用综合参数“相对局部抗炎活性指数（IRTAA）”来比较渗透/保留药物量的效力，该参数是皮肤渗透/保留和药物相对效力的乘积。与 ETF 凝胶相比，DIC 凝胶的 IRTAA 在经皮输送和皮肤保留方面分别高 94-667 倍和 72-208 倍。这些较高的 IRTAA 表明，这种局部制剂递送的 DIC 将实现更高的生物活性，并形成一个有效的药物储存库，这与其随后的长效释放相关。
