An open multicentre study of tropisetron for cisplatin-induced nausea and vomiting.

OBJECTIVES: (i) To assess the efficacy and tolerability of tropisetron when used for acute and delayed cisplatin-induced emesis. (ii) To investigate whether dexamethasone added to tropisetron improves the control of emesis for patients who do not achieve a complete response to tropisetron alone. (iii) To assess sex of the patient and alcohol intake as prognostic factors for nausea and vomiting.

DESIGN: A prospective open label phase II trial over one or two cycles of chemotherapy. Data collection was based on observed response and patients' self-reporting.

SETTING: Twenty Australian tertiary care hospitals in 1994.

PATIENTS: 102 male and female patients from 18 to 75 years with histologically confirmed malignancy receiving their first chemotherapy containing > or = 50 mg/m2 cisplatin.

INTERVENTION: In Cycle 1 tropisetron 5 mg was given intravenously before chemotherapy on Day 1, then 5 mg orally before breakfast on Days 2 to 6. In Cycle 2, dexamethasone 20 mg intravenously on Day 1, then 8 mg orally on Days 2 to 6 could be added to tropisetron if a complete antiemetic response had not been achieved in Cycle 1.

MAIN OUTCOME MEASURES: Number of vomiting episodes and severity of nausea for 6 days after chemotherapy; severity of side effects; patient satisfaction with chemotherapy treatment; oestradiol levels in women; and past alcohol consumption in men and women.

RESULTS: (i) The complete response rate (CR) for acute emesis in Cycle 1 was 64% (95% confidence interval [CI], 54%-72%), with 84% (95% CI, 76%-90%) having < or = 2 vomits. The CR for delayed emesis was 24% (95% CI, 17%-32%). The CR for acute nausea was 56% (95% CI, 47%-66%), with 97% (95% CI, 91%-99%) having < or = 2 nausea episodes. The CR for delayed nausea was 21% (95% CI, 14%-30%). Seventy-one patients received Cycle 2. The main side effects were headache (20 patients) and constipation (16 patients). The control of acute emesis was rated as "good" or "very good" by 68% of investigators; 85% rated the tolerability of treatment as "good" or "very good". Treatment was rated as "very satisfactory" or "satisfactory" by 52% of patients. (ii) The CR for acute emesis with dexamethasone added was 78% (95% CI, 64%-88%). (iii) Women with lower oestradiol levels had better control of emesis, although this difference was not statistically significant. Chronic alcohol intake and binge drinking were strongly associated with a complete acute antiemetic response.

CONCLUSIONS: Tropisetron was effective for acute cisplatin-induced emesis; adding dexamethasone enhanced this response. Both single and combined therapy had less effect on delayed emesis. The impact of alcohol on control of emesis is a chronic rather than acute phenomenon which requires prospective testing.