Comparison of three tropisetron-containing antiemetic regimens in the prophylaxis of acute and delayed chemotherapy-induced emesis and nausea.

There is still controversy as to what constitutes the optimal therapy for acute and delayed chemotherapy-induced emesis and nausea. We conducted a three-armed randomized multi-centre study in 193 chemotherapy-naive patients receiving highly emetogenic chemotherapy inducing both acute and delayed symptoms (cisplatin ≥50 mg/m2, carboplatin ≥300 mg/m2, cyclophosphamide ≥750 mg/m2, ifosfamide ≥1.5 g/m2 on day 1). Group A: 1×5 mg tropisetron i.v. on day 1+2, then 10 mg p.o. (oral dose now recommended: 5 mg); group B: tropisetron as for A+dexamethasone, 20 mg i.v., on days 1+2, then 4 mg i.v./p.o.; group C: tropisetron as for A+metoclopramide, 20 mg i.v.+2×10 mg p.o. on day 1, then 3×10 mg p.o. Treatment was continued for at least 2 days after the end of chemotherapy. Tropisetron+dexamethasone was significantly superior to tropisetron alone both for acute (P=0.0064) and delayed (P=0.0053) emesis. Complete control of acute and delayed emesis (nausea) was achieved in 80% (75%) and 53% (46%) in group A, 97% (90%) and 80% (58%) in group B, and 86% (80%) and 49% (45%) in group C. Patients completely asymptomatic during the whole cycle accounted for 26% of those in group A, 49% in group B and 28% in group C. The most frequent adverse events were constipation (16.6%), headache (7.3%) and tiredness (7.3%). Once-daily tropisetron+dexamethasone over several days is well tolerated and is a simple means of achieving further significant improvement in the efficacy of tropisetron against acute and delayed symptoms.