Vapitadine (hydrochloride)

Vapitadine hydrochloride (Compound 3a) is a selective, orally active and nonsedating antihistamine agent, which exhibits a good binding affinity with human cloned histamine H1 receptor with a Ki of 19 nM. Vapitadine hydrochloride decreases the histamine-induced lethality (ED50 is 0.056-1.2 mg/kg), antagonizes the cutaneous reactions to histamine (ED50 is 0.51-1.4 mg/kg) in rats[1].