Aprepitant plus palonosetron versus dexamethasone plus palonosetron in preventing chemotherapy-induced nausea and vomiting in patients with moderate-emetogenic chemotherapy: A randomized, open-label, phase 3 trial

Despite significant progress in the prevention of chemotherapy-induced nausea and vomiting (CINV) by using dexamethasone combined with palonosetron for patients who received moderate-emetogenic chemotherapy (MEC), some of these patients still suffer from CINV. We evaluated whether aprepitant combined with palonosetron can improve the efficacy in the prevention of CINV in patients receiving MEC.This was a single-centre, open-label, phase III, randomized controlled trial, which was done at the Sixth Affiliated Hospital of Sun Yat-sen University of China. The registered patients planned to receive mFOLFOX6 (oxaliplatin, leucovorin, and 5-fluorouracil) but had not received any chemotherapy previously. The patients were randomized in a 1:1 ratio to the aprepitant group (aprepitant 125 mg orally on day 1, 80 mg on day 2-3) and the dexamethasone group (dexamethasone 10 mg intravenously on day 1, 5 mg on days 2 and 3), both groups with palonosetron 0.25 mg intravenously on day 1. The primary endpoint was the proportion of patients who achieved a complete response (CR), defined as the absence of vomiting and no use of rescue medications in the overall phase (0-120 h). The primary outcome and safety were assessed in the modified intention-to-treat population, which excluded all patients who used estazolam within 24 h before registration and those who refused to keep a diary documenting the severity of nausea, frequency of vomiting, and the use of rescue therapy. This trial is registered with ClinicalTrials.gov, NCT02909478.Between Sep 1, 2017, and Oct 23, 2019, 320 patients were enrolled, and 315 patients were evaluated. The proportion of patients who achieved CR was significantly higher with aprepitant than that noted with dexamethasone in the overall phase (88.8% vs. 74.2%; P = 0.0010; rate difference, RD 15%, 95% CI, 6% to 23%) and in the delayed phase (25-120 h), 90.6% vs. 75.5%, (P < 0.0001; RD 15%, 95%CI, 7% to 23%). No significant difference of CR rate was observed in the acute phase (0-24 h), 93.8% vs. 93.5%, (P = 0.94; RD 0%, 95% CI, -5% to 6%)). In the overall phase, the incidence of insomnia (P < 0.0010), dyspepsia (P = 0.038), and flushing (P = 0.0010) reported by the patients was significantly higher in the dexamethasone group than that in the aprepitant group.Aprepitant combined with palonosetron is superior to dexamethasone combined with palonosetron in patients who received the MEC regimen mFOLFOX6 in terms of preventing CINV.The National Key R&D Program of China (2019YFC1316000) and the National Natural Science Foundation of China (81974369).