INCB3344

INCB3344 is a potent, selective and orally bioavailable CCR2 antagonist with IC₅₀ values of 5.1 nM (hCCR2) and 9.5 nM (mCCR2) in binding antagonism and 3.8 nM (hCCR2) and 7.8 nM (mCCR2) in antagonism of chemotaxis activity. IC50 & Target: IC50: 5.1 nM (hCCR2), 9.5 nM (mCCR2)^[1] In Vitro: INCB3344 is a potent antagonist towards rat and cynomolgus CCR2 as well, displaying IC₅₀ values of 7.3 and 16 nM in binding antagonism and 2.7 and 6.2 nM in antagonism of chemotaxis activity, respectively. INCB3344 is a selective hCCR2 antagonist, exhibiting IC₅₀ values of more than 1 μM against a panel of >50 ion channels, transporters, chemokine receptors and other selected GPCRs. It is also a selective mCCR2 antagonist, showing IC₅₀ values of >1 μM and >3 μM against murine CCR1 and murine CCR5, respectively, the two most homologous chemokine receptors to mCCR2^[1]. Characterization of the pharmacological activity of INCB3344 is first evaluated by testing its ability to inhibit CCL2 binding to CCR2 in a whole cell binding assay using a murine monocyte cell line, WEHI-274.1 and ¹²⁵I-labeled mCCL2 as a tracer. The binding IC₅₀ of INCB3344 in this assay is determined to be 10±5 nM, and inhibition of >90% binding is observed at a concentration of 90 nM^[2]. In Vivo: When administered intravenously to CD-1 mice, INCB3344 exhibits a high clearance and a moderate volume of distribution, resulting in a short half life of 1 h. Despite its high clearance, however, good oral exposure is achieved, with an AUC at 2664 nM h at a dose of 10 mg/kg. The oral bioavailability is 47%. By comparison, slightly better oral exposure (AUC=3888 nM h) is obtained when administered orally to Balb/c mice at the same dose. This PK property, couple with its potent anti-mCCR2 activity and good selectivity, makes this compound suitable for model studies in rodents^[1]. INCB3344 prevents Deoxycorticosterone acetate/salt-induced changes in vascular expression of CCR2. In a separate series of experiments, CCR2 expression is elevated (≈1.5-fold higher) in aortas from mice that receive INCB3344 from days 7 to 21 of the Deoxycorticosterone acetate/salt treatment period compare with sham animals; however, this level of CCR2 expression is significantly lower than that observed in the vehicle-treated group (P<0.05, n=6). Likewise, increased expression of its receptor ligand CCL2 in Deoxycorticosterone acetate/salt-treated mice is blunted in mice receiving INCB3344 (P<0.05, n=6). By contrast, levels of CCL7, CCL8, and CCL12 are elevated to similar extents in Deoxycorticosterone acetate/salt-treated mice receiving vehicle or INCB3344^[3].