In this article, we will discuss Infigratinib (Mechanism of Action). So, let’s get started.
Mechanism of Action
Infigratinib is a small molecule kinase inhibitor of FGFR with IC50 values of 1.1, 1, 2, and 61 nM for FGFR1, FGFR2, FGFR3, and FGFR4, respectively. The major human metabolites of infigratinib, BHS697 and CQM157, have similar in vitro binding affinities for FGFR1, FGFR2, and FGFR3 compared to infigratinib. Infigratinib inhibited FGFR signaling and decreased cell proliferation in cancer cell lines with activating FGFR amplifications, mutations, or fusions. Constitutive FGFR signaling can support the proliferation and survival of malignant cells. Infigratinib had anti-tumor activity in mouse and rat xenograft models of human tumors with activating FGFR2 or FGFR3 alterations, including two patient-derived xenograft models of cholangiocarcinoma that expressed FGFR2-TTC28 or FGFR2-TRA2B fusions. Infigratinib demonstrated brain-to-plasma
concentration ratios (based on AUC0-inf) of 0.682 in rats after a single oral dose.
Infigratinib increased serum phosphate levels due to FGFR inhibition. Serum phosphate increased with increasing exposures across the dose range of 20 to 150 mg once daily (0.16 to 1.2 times the approved recommended dosage), with increased risk of hyperphosphatemia with higher exposure to Infigratinib.
At the recommended dosing regimen, Infigratinib does not result in a large mean increase (i.e., >20 msec) in the QTc interval. The QT effect of infigratinib at higher exposures associated with CYP3A inhibition has not been studied.