Optimal combination therapy with Navoban (tropisetron) in patients with incomplete control of chemotherapy-induced nausea and vomiting. The Belgian Navoban Group

Even with the availability of potent and selective serotonin antagonists, chemotherapy-induced nausea and vomiting remain a major problem for many patients. This study aims to evaluate the benefit of combination therapy based on Navoban (tropisetron) in patients who had incomplete control of nausea and/or vomiting induced by chemotherapy when using Navoban as a single antiemetic agent. In their first chemotherapy course, 1072 patients planned to receive at least two identical cycles of emetogenic chemotherapy were treated with 5 mg Navoban once daily. To evaluate three treatments additional to the recommended 5 mg once-daily Navoban regimen during Course 2 in those patients who had shown incomplete control of nausea and/or vomiting on any day of Course 1, a 2 x 2 x 2 factorial design was employed. Of these patients, 445 were centrally randomised to receive an additional dose of open-label dexamethasone (Day 1, 0.2 mg/kg i.v.; Days 2-6, 8 mg p.o.) and/or open-label alizapride (Day 1, 100 mg i.v. and 4 x 50 mg p.o.; Days 2-6, 4 x 5 mg p.o.) and/or double-blind Navoban--that is, doubling the dose to 10 mg once daily or placebo. Complete response rates during Course 1 (CRR, no nausea and no vomiting) were, for Day 1, 72% and for Days 1-6, 48%. More complete responders were observed when dexamethasone was added during Course 2, both on Day 1 (76% vs. 66%, p = 0.020) and on Days 1-6 (50% vs. 34%, p = 0.0004).(ABSTRACT TRUNCATED AT 250 WORDS)