Vesatolimod (GS-9620) is an effective and specific orally active agonist of Toll-like receptor 7.

TLR7:291 nM(EC50)

Vesatolimod迅速进入细胞，并倾向于定位于内溶酶体区域并从此发出信号。为验证这一假设，采用氚标记的Vesatolimod（3H-Vesatolimod）测量了其在Daudi细胞中的细胞摄取动力学。3H-Vesatolimod的积累动力学快速，大约三十分钟内达到依赖浓度的稳态平衡。测得的3H-Vesatolimod细胞内浓度是用于处理细胞的3H-Vesatolimod外部浓度的5倍。随着3H-Vesatolimod浓度的增加，细胞内3H-Vesatolimod浓度的增加大致成比例[1]。

单次口服GS-9620，剂量为0.3和1 mg/kg的未感染黑猩猩，显示剂量和暴露量相关的血清IFN-α、选定细胞因子/趋化因子以及外周血和肝脏中干扰素刺激基因（ISG）的诱导。GS-9620在口服后的最大血浆浓度（Cmax）分别为剂量0.3（n=3）、1 mg/kg（n=3和n=4）时为3.6±3.5、36.8±34.5和55.4±81.0 nM。血清干扰素反应峰值在给药后8小时出现。在0.3和1 mg/kg剂量下，诱导的血清IFN-α平均峰值分别为66和479 pg/mL。GS-9620治疗在0.3 mg/kg剂量下诱导外周血单核细胞（PBMC）中的ISG转录物，包括ISG15、OAS-1、MX1、IP-10（CXCL10）和I-TAC（CXCL11），以及1 mg/kg剂量下诱导PBMC和肝脏中的ISG转录物[2]。

Biochemical assays: Biochemical assays are performed by a broad-coverage, TR-FRET-based kinase binding assay platform.

GS-9620 is dissolved in DMSO and stored, and then diluted with appropriate medium before use[1]. Daudi cells are incubated for indicated times with varying concentrations [3H]GS-9620 (0.7μCi/mL). Cell associated radioactivity is extracted with ice cold 80% ethanol and measured using liquid scintillation counting. The total amount of GS-9620 in cells is calculated from a calibration curve for GS-9620 mass versus radioactivity. Cell volume is measured[1].