Efficacy and safety of oral palonosetron compared with IV palonosetron administered with dexamethasone for the prevention of chemotherapy-induced nausea and vomiting (CINV) in patients with solid tumors receiving cisplatin-based highly emetogenic chemotherapy (HEC).

Purpose: This study aims to compare the efficacy and safety of oral palonosetron with intravenous (IV) palonosetron for the prevention of cisplatin-related chemotherapy-induced nausea and vomiting (CINV).

Methods: A multinational, randomized, double-blind study enrolling adult chemotherapy-naive patients with malignant solid tumors scheduled to receive cisplatin-based highly emetogenic chemotherapy (HEC). Patients received oral palonosetron (0.50 mg) or IV palonosetron (0.25 mg), each with oral dexamethasone. The primary objective was to demonstrate non-inferiority in terms of patients with a complete response (CR, no emesis/no rescue medication) within the acute phase (0-24 h after chemotherapy administration).

Results: Of the 743 patients randomized, 739 received study medications and 738 were included in the full analysis set. The CR rate in the acute phase was high for both groups (oral 89.4 %; IV 86.2 %). As this difference in proportions (stratum-adjusted Cochran-Mantel-Haenszel method) was 3.21 % (99 % confidence interval (CI) -2.74 to 9.17 %), non-inferiority was demonstrated (since the lower limit of the 99 % CI was closer to zero than the predefined margin of 15 %). Treatment-emergent adverse events (TEAEs) related to the study drug were rare (oral 3.2 %; IV 6.5 %). No TEAEs related to study drug leading to discontinuation were reported.

Conclusion: Non-inferiority of oral versus IV palonosetron was demonstrated. The CR rate in the acute phase was >86 % in both patient groups. The safety profiles were comparable.