Norverapamil (hydrochloride)

Norverapamil hydrochloride ((±)-Norverapamil hydrochloride), an N-demethylated metabolite of Verapamil, is a L-type calcium channel blocker and a P-glycoprotein (P-gp) function inhibitor^[1][2]. IC50 & Target:Calcium channel blocker^[1]
P-glycoprotein (P-gp) inhibitor^[2] In Vitro: Norverapamil hydrochloride ((±)-Norverapamil hydrochloride) is similarly effective as verapamil at inhibiting isoniazid and rifampicin tolerance and killing of intracellular M. tuberculosis in the absence of other drugs. norverapamil, also inhibits macrophage-induced tolerance and achieves similar serum levels to verapamil^[1].
Verapamil and its major metabolite norverapamil were identified to be both mechanism-based inhibitors and substrates of CYP3A and reported to have non-linear pharmacokinetics in clinic^[3]. In Vivo: Norverapamil hydrochloride (9 mg/kg; p.o.), a major metabolite of verapamil, has terminal half-life, AUC and Cmax values of 9.4 hours, 260 ng h/ml, and 41.6 ng/mL, respectively^[4].