TC-2559 idifumarate is a CNS-selective, orally active α4β2 subtype of nicotinic acetylcholine receptor (nAChR) partial agonist with an EC 50 of 0.18 μM. It exhibits selectivity for α4β2 receptors over α2β4, α4β4, and α3β4 receptors, with EC 50 s ranging from 10 to 30 μM. TC-2559 difumarate also demonstrates antinociceptive effects.

TC-2559 difumarate (1-10 mg/kg; i.p.) dose dependently reduces acute formalin-induced biphasic nociceptive responses in mice[2]. TC-2559 difumarate (0.3-3 mg/kg; i.p.) dose dependently inhibits CCI-induced neuropathic pain in rats[2]. Animal Model: Adult male mice (body weight 15-30 g) (formalin test)[2]Dosage: 1, 3, 10 mg/kg Administration: I.p. Result: Dose dependently reduced both early and late phases of formalin induced nociceptive behavioral responses. Animal Model: Adult male SD rats (body weight 200-220 g) (chronic constriction injury (CCI))[2]Dosage: 0.3, 1, 3 mg/kg Administration: I.p. Result: Significantly reversed CCI induced the paw withdrawal threshold decreases.