Azasetron (hydrochloride) is a selective 5-HT3 receptor antagonist with IC50 of 0.33 nM used in the management of nausea and vomiting induced by cancer chemotherapy. Target: 5-HT3 ReceptorAzasetron (hydrochloride) is a 5-HT3 receptor antagonist which is used as an anti-emetic.Azasetron (hydrochloride) inhibited the specific binding of [3H]quipazine to 5-HT3 receptors at the synaptic membranes of the rat cerebral cortex with a Ki value of 2.9 nM. Azasetron (hydrochloride) showed low affinity for histamine H1 receptors (IC50 = 4.4 microM) but it could not reveal any affinities for the other receptors (5-HT1A, 5-HT2, dopamine D1, dopamine D2, alpha 1-adrenoceptor, alpha 2-adrenoceptor, muscarine and benzodiazepine) even at a 10 microM concentration [1]. Azasetron (hydrochloride) (0.1-1.0 mg/kg) dose-dependently prolonged the latency to the first vomiting and decreased the number of vomitings induced by cisplatin in dogs. Azasetron (hydrochloride) is an orally active antiemetic compound against cisplatin and doxorubicin/cyclophosphamide-induced emeses; and its the antiemetic potency is similar to those of granisetron and ondansetron, but superior to those of metoclopramide and domperidone [2].

References:
[1]. Sato, N., et al., Antagonistic activity of Y-25130 on 5-HT3 receptors. Jpn J Pharmacol, 1992. 59(4): p. 443-8.
[2]. Haga, K., et al., The effects of orally administered Y-25130, a selective serotonin3-receptor antagonist, on chemotherapeutic agent-induced emesis. Jpn J Pharmacol, 1993. 63(3): p. 377-83.