Abstract：
Winlevi® (clascoterone) topical cream (1%, w/w) was approved by the U.S. FDA for the treatment of acne vulgaris in patients 12 years of age and older. The active ingredient, clascoterone, is not stable in physiological solutions and can hydrolyze to cortexolone at body temperature. Instability of clascoterone poses a significant challenge in accurately assessing the rate and extent of clascoterone permeation in vitro. Therefore, the purpose of this study was to develop an in vitro skin permeation test (IVPT) method, and a robust analytical method, that can minimize hydrolyzation of clascoterone during the study for quantification of clascoterone. Two IVPT methods, using either vertical diffusion cells or flow-through cells, were developed and compared to evaluate in vitro permeation of clascoterone from Winlevi. A liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was developed to monitor the level of clascoterone and cortexolone in the IVPT samples. The analytical method features a 2-min high-throughput analysis with good linearity, selectivity, and showed a lower limit of quantitation (LLOQ) of 0.5 ng/mL for both clascoterone and cortexolone. The in vitro skin permeation of clascoterone and cortexolone was observed as early as 2 h in both IVPT methods. A substantive amount of clascoterone was found to hydrolyze to cortexolone when using the vertical static diffusion cells with aliquot sampling. Conversely, degradation of clascoterone was significantly minimized when using the flow-through diffusion cells with fractional sampling. The data enhanced our understanding of in vitro permeation of clascoterone following topical application of the Winlevi topical cream, 1% and underscores the importance of IVPT method development and optimization during product development.
摘要：
Winlevi®（克拉昔克龙）外用乳膏（1%，w/w）被美国FDA批准用于治疗12岁及以上患者的寻常痤疮。活性成分，克拉昔克龙,在生理溶液中不稳定，在体温下可以水解为皮质酮。在准确评估体外克拉维酮渗透的速率和程度方面,克拉维酮的不稳定性提出了重大挑战。因此,本研究的目的是开发一种体外皮肤渗透试验(IVPT)方法，和一种稳健的分析方法，这可以最大程度地减少在定量研究期间的克拉维酮的水解。两种IVPT方法，使用垂直扩散池或流通池，开发并进行比较，以评估Winlevi的clascoterone的体外渗透。建立了液相色谱-串联质谱（LC-MS/MS）方法，以监测IVPT样品中克拉维科酮和皮质酮的水平。该分析方法具有2分钟的高通量分析，线性良好，选择性,并显示克拉维科酮和皮质酮的定量下限（LLOQ）为0.5ng/mL。在两种IVPT方法中，早在2小时内就观察到了克拉维科酮和皮质酮的体外皮肤渗透。当使用等份样品的垂直静态扩散细胞时，发现大量的克拉维酮水解为皮质酮。相反，当使用具有分数采样的流通扩散细胞时，克拉维酮的降解显着最小化。这些数据增强了我们对局部应用Winlevi局部乳膏后克拉维酮体外渗透的理解，1％，强调了产品开发过程中IVPT方法开发和优化的重要性。
