Abstract Background Chemotherapy-induced nausea and vomiting (CINV) significantly impact the patients’ quality of life. Whether the granisetron transdermal delivery system (GTDS) offers better protection than palonosetron against long-delayed (120–168 h) CINV after highly or moderately emetogenic chemotherapy (HEC/MEC) had not been prospectively tested. Methods A multicenter, randomized clinical study was conducted in China. Patients scheduled to receive either HEC or MEC were randomly assigned (1:1) to GTDS or palonosetron, each in combination with a neurokinin-1 receptor antagonist (NK1-RA) and dexamethasone. The primary endpoint was the complete response (CR; no vomiting and no rescue medication) rate during the long-delayed phase (120-168 hours), stratified by HEC and MEC categories, to demonstrate the superiority of GTDS over palonosetron. Results Overall, 150 patients received either GTDS or palonosetron respectively. We found that the GTDS group demonstrated a significantly higher long-delayed CR rate (97.3%) than the palonosetron group (92%) (p = 0.04). This advantage was driven predominantly by the HEC subgroup (GTDS 97.5% vs palonosetron 90.8%, p = 0.028). No significant differences were observed between the groups for the acute (0–24 h, 92.7% vs 90.0%; p = 0.412), delayed (24–120 h, 80.0% vs 76.0%; p = 0.403), extended-delayed (24–168 h, 80.7% vs 75.3%; p = 0.265), or overall (0–168 h, 78.0% vs 74.0%; p = 0.417) phases. Conclusion A GTDS-based triple antiemetic regimen can effectively control CINV associated with HEC or MEC. It provides a convenient alternative route for delivering granisetron for up to 7 days, with superior efficacy in controlling long-delayed CINV. Trial registration: Clinicaltrials.gov Identifier NCT04912271 (in-house ethic number: YBCSG-21-04)
Liu et al. (Fri,) studied this question.