Indisetron Hydrochloride

The aim of this study was to estimate interindividual differences in the antiemetic effects of 5-HT(3) receptor antagonists by evaluating the influence of pharmacokinetics on 5-HT(3) receptor occupancies, based on receptor occupancy theory.

We analyzed interindividual differences of 5-HT(3) receptor occupancies and antiemetic effects after the oral and/or intravenous administration of standard doses of the following 5-HT(3) receptor antagonists: azasetron, granisetron, indisetron, ondansetron, ramosetron, and tropisetron.

The interindividual difference between maximum and minimum 5-HT(3) receptor occupancies after oral administration ranged from 0.6% to 64.0%, and that difference after intravenous administration ranged from 0.6% to 29.6%. Following oral administration, the interindividual difference between maximum and minimum complete vomiting inhibition rates ranged from 0.2% to 16.1%. After intravenous administration, that difference ranged from 0.8% to 52.5%.

Interindividual differences in the clinical effects of 5-HT(3) receptor antagonists could be evaluated based on receptor occupancy theory, and the differences varied among drugs. Drug selection considering these individual variations might be useful for the patients who experienced vomiting associated with chemotherapy.

We set out to determine the efficacy of indisetron hydrochloride for the management of chemotherapy-induced nausea and vomiting including carboplatin for lung cancer. Indisetron hydrochloride was given orally to 32 patients (indisetron group), and intravenous 5-HT3 receptor antagonists were given to 24 patients (control group). The number of patients with nausea or vomiting occurring within 24 hours and 24 to 72 hours after chemotherapy was measured. The complete inhibition of the vomiting within 24 hours after chemotherapy was 100% in the indisetron group and 95.8% in the control group. Twenty-four to 72 hours after chemotherapy, the complete inhibition of vomiting rate was 97.1% and 95.8%, respectively. In addition, the complete inhibition of nausea rate within 24 hours after chemotherapy was 87.5% in the indisetron group and that was 95.8% in the control group. The complete inhibition of nausea rate 24 to 72 hours after chemotherapy was 56.3% and 70.8%, respectively. No serious adverse events were observed. The comparison of the efficacy between the indisetron group and control groups did not reach statistical significance (p> 0.05). These findings suggest that prophylactic administration of indisetron hydrochloride is useful for the inhibition of acute and delayed nausea and vomiting caused by chemotherapy in lung cancer patients.