Dose-ranging antiemetic evaluation of the serotonin antagonist tropisetron in patients receiving anti-cancer chemotherapy.
BACKGROUND: Tropisetron (ICS 205-930) antagonizes the serotonin type 3 receptor and has antiemetic activity in animals given cisplatin. Its mean serum half-life in 11.1 hours. METHODS: In this dose-ranging trial, 22 patients undergoing anti-cancer chemotherapy received 24 courses of a single intravenous infusion of tropisetron beginning 30 minutes before chemotherapy. Four dose levels were explored (range, 12-48 mg/m2). RESULTS: Toxicities were mild and included headache, transient elevations of serum alanine transaminase and/or aspartate transaminase levels, and sedation. No akathisia or acute dystonic reactions were observed. Thirty-six percent of patients had no emesis, and 58% had two or fewer emetic episodes. Ten patients received high-dose cisplatin (dose, > or = 100 mg/m2) as initial chemotherapy. Of these, 30% had no emesis, and 60% had two or fewer episodes. CONCLUSIONS: Tropisetron can be administered safely in the doses tested with no dose-limiting toxicities. The encouraging antiemetic efficacy, mild toxicities, lack of extrapyramidal effects, and convenience of a single 15-minute infusion regimen make this drug appropriate for study in additional trials.