In view of the similarity in chemical structure of the available 5HT 3-receptor antagonists it is assumed, whilst these agents all act at the same receptor, that failure to one agent would predict subsequent failure to all 5HT 3-receptor antagonists. We conducted a randomized double blind trial of granisetron 3 mg plus dexamethasone 10 mg versus continued treatment with ondansetron 8 mg plus dexamethasone 10 mg in patients with protection failure on ondansetron 8 mg plus dexamethasone 10 mg during the first 24 hours following highly emetogenic chemotherapy. Of 40 eligible patients, 21 received ondansetron + dexamethasone and 19 received granisetron + dexamethasone. We found a significant benefit from crossing-over to granisetron after failure on ondansetron. Of the 19 patients who crossed over to granisetron, 9 patients obtained complete protection, whereas this was observed in 1 of the 21 patients continuing ondansetron, P = 0.005. These results indicate that there is no complete cross-resistance between 5HT 3-receptor antagonists, and that patients who have acute protection failure on one 5H T3-receptor antagonist should be offered cross-over to another 5HT 3-receptor antagonist.

doi.org/10.1054/bjoc.2001.2045, hdl.handle.net/1765/55017
British Journal of Cancer
Department of Medical Oncology

de Wit, R., de Boer, A., Vd Linden, G. H. M., Stoter, G., Sparreboom, A., & Verweij, J. (2001). Effective cross-over to granisetron after failure to ondansetron, a randomized double blind study in patients failing ondansetron plus dexamethasone during the first 24 hours following highly emetogenic chemotherapy. British Journal of Cancer, 85(8), 1099–1101. doi:10.1054/bjoc.2001.2045