An overview of randomised studies comparing 5-HT3 receptor antagonists to conventional anti-emetics in the prophylaxis of acute chemotherapy-induced vomiting.

Ten years after it was demonstrated in the ferret that cisplatin-induced emesis could be blocked by the selective 5-HT3 receptor antagonist MDL 72222, 5-HT3 receptor antagonists have become routine anti-emetic agents for chemotherapy-induced emesis. However, although in association with highly emetogenic, mainly cisplatin-containing regimens, the use of these agents is well justified, the net benefit of 5-HT3 receptor antagonists in association with moderately emetogenic regimens has not been that well clarified. Here, we present an overview of 30 randomised studies comparing 5-HT3 antagonists with the conventional anti-emetics in the prophylaxis of acute vomiting induced by cytotoxic chemotherapy. A meta-analysis showed that 5-HT3 antagonists reduce the risk of acute vomiting in comparison to conventional anti-emetics both with cisplatin treatments (15 trials; odds ratio 0.60; 95% confidence interval 0.51-0.70) and with moderately emetogenic treatments (11 trials; odds ratio 0.47; 95% confidence interval 0.39-0.58). The risk of acute vomiting seems to be further reduced when 5-HT3 antagonists are combined with dexamethasone.