PF-01247324 is a blocker of the tetrodotoxin-resistant (TTX-R) sodium channel Nav1.8 (IC50 = 0.19 μM for human Nav1.8). It is selective for Nav1.8 over Nav1.1, Nav1.2, Nav1.5, and Nav1.7 channels (IC50s = 13, 12.8, 9, and 19 μM, respectively) as well as ether-a-go-go (ERG) potassium channels (IC50 = 30 μM). PF-01247324 blocks Nav1.8 channels in a VSP-FRET assay using HEK293 cells (IC50 = 2.6 μM). In vivo, PF-01247324 (100 mg/kg) reduces phase 2 flinching in a rat model of formalin-induced persistent pain. It increases latency to lift the inflamed paw and latency to paw withdrawal in rat models of carrageenan-induced thermal hyperalgesia and mechanical hyperalgesia induced by complete Freund''s adjuvant (CFA), respectively.
