Aprepitant versus metoclopramide, both combined with dexamethasone, for the prevention of cisplatin-induced delayed emesis : a randomized, double-blind study

Background: A combination of aprepitant, a 5-HT3 receptor antagonist (r.a.), and dexamethasone is recommended for the prophylaxis of cisplatin-induced nausea and vomiting in the acute phase, and aprepitant + dexamethasone (A + D) in the delayed phase. The aim of this study was to verify if A + D is superior to metoclopramide plus dexamethasone (M + D) in preventing delayed emesis in cancer patients receiving the same prophylaxis for acute emesis. Patients and methods: A randomized double-blind study comparing A + D versus M+ D was completed in previously untreated cancer patients. Before chemotherapy, all patients were treated with intravenous palonosetron 0.25 mg and dexamethasone 12 mg, and oral aprepitant 125 mg. On day 2-4, patients randomly received oral dexamethasone 8 mg plus aprepitant 80 mg once daily (days 2-3) or metoclopramide 20 mg four times daily plus dexamethasone 8 mg bid. Primary endpoint was rate of complete response (no vomiting, no rescue treatment) in day 2-5 after chemotherapy. Results: Due to difficulty in the accrual of patients, 303 of the 480 planned patients were enrolled, 284 were fully evaluable, 147 receiving A + D, 137 M+ D. Day 1 results were similar in both arms. On day 2-5, complete response rate was not significantly different (80.3% with A + D versus 82.5% with M+ D, P < 0.38, respectively), and all secondary endpoints were also similar (complete protection, total control, no vomiting, no nausea, and score of Functional Living Index-Emesis; P < 0.24). Adverse events incidence was not significantly different between the two treatments. Conclusions: In cancer patients submitted to cisplatin-based chemotherapy, receiving the same antiemetic prophylaxis for acute emesis, A + D is not superior to M+ D in preventing delayed emesis, and both treatments present similar toxicity.