Purity >98%. Nav 1.8 is a tetrodotoxin-resistant (TTX-R) sodium channel with high activation threshold and slow inactivating kinetics that is highly expressed in small-diameter sensory neurons and has been implicated in signaling various types of pain. A-803467 is a sodium channel blocker with high-affinity and selectivity for inhibiting human Nav 1.8 sodium channels (IC50 = 8 nM when stimulated at half-maximal inactivation and IC50 = 79 nM at a resting state). 1 This compound is unusual in that it blocks hNav1.8 at negative resting membrane potentials (many small molecule sodium channel blockers show a reduced affinity for the resting state) and does not demonstrate significant frequency-dependent block during a 10 Hz pulse train. A-803467 dose-dependently reduces behavioral responses in a variety of neuropathic and inflammatory pain models.