Ondansetron versus granisetron, both combined with dexamethasone, in the prevention of cisplatin-induced emesis. Italian Group of Antiemetic Research.

BACKGROUND

Differences in pharmacodynamic and pharmacokinetic characteristics among serotonin-receptor antagonists have been reported in preclinical studies. This prompted us to carry out a study to determine whether such differences are important in terms of clinical efficacy or tolerability.

PATIENTS AND METHODS

973 consecutive cancer patients scheduled to receive cisplatin for the first time (at doses > or = 50 mg2), entered a double-blind multicenter randomized study comparing intravenous ondansetron 8 mg versus granisetron 3 mg. Dexamethasone 20 mg was added to both serotonin antagonists. On days 2 to 4 after chemotherapy all patients received oral metoclopramide plus intramuscular dexamethasone as antiemetic prophylaxis for delayed emesis. Nausea and vomiting were assessed daily until day 6 after chemotherapy.

RESULTS

We evaluated 966 patients (483 receiving ondansetron and 483 granisetron). Complete protection from acute vomiting/nausea was obtained in 79.3%/72.0% of patients receiving ondansetron and in 79.9%/71.8% of those receiving granisetron. Complete protection from delayed vomiting/nausea as obtained in 69.7%/52.9% and 70.0%/49.6% of patients receiving the ondansetron or granisetron regimens, respectively. Adverse effects were mild and not significantly different between the two antiemetic regimens.

CONCLUSIONS

Ondansetron 8mg and granisetron 3 mg, both combined with dexamethasone, showed similar efficacy and tolerability in the prevention of cisplatin-induced emesis. The choice between the two regimens can be dictated by their respective purchase prices.