SAR-20347 is an orally active, ATP-competitive, TYK2- and JAK1-selective tyrosine kinase inhibitor (IC50 = 13 nM/TYK2 & 59 nM/JAK1 vs. 0.88 μM/JAK2 & 1.44 μM/JAK3 with 10 μM ATP) that effectively inhibits cellular TYK2- (IL12-induced pSTAT4 IC50 = 107 nM/CD4+ cells, 126 nM/NK-92) and JAK1- (IL6-induced pSTAT3 IC50 = 345 nM/TF-1, 407 nM/CD14+ cells) mediated signaling with little affinity toward 72 other kinases. SAR-20347 suppresses IL22-induced serum amyloid A (by 44%; 50 mg/kg p.o. 30 min prior to 10 μg IL22 i.p.) and alleviates imiquimod-induced psoriasis-like dermatitis (30 min prior and 5 h post daily 62.5 mg 5% imiquimod cream) in mice in vivo.
