Single-dose palonosetron and dexamethasone in preventing nausea and vomiting induced by moderately emetogenic chemotherapy in breast and colorectal cancer patients.

Aims and background. Palonosetron, a unique second-generation 5-HT3 receptor antagonist, has been demonstrated to control emesis related to chemotherapy-induced nausea and vomiting (CINV). The aim of this study was to evaluate the efficacy and tolerability of palonosetron followed by a single dose of dexamethasone in patients with breast cancer (BC) or colorectal cancer (CRC) receiving moderate emetogenic chemotherapy (MEC). Methods and study design. Chemotherapy-naive BC and CRC patients were given MEC as adjuvant or first-line treatment. Palonosetron (0.25 mg IV) and dexamethasone (8 mg IV) were administered before chemotherapy on day 1. The primary endpoint was complete response (CR; no vomiting and no use of rescue medication) during the overall study period (days 1-5). The antiemetic response was evaluated during the acute (day 1) and delayed (days 2-5) phases. Results. Sixty-eight patients were enrolled (median age 61 years, 56 females; BC = 40, CRC = 28). CR was observed in 46 of 68 patients (67.6%), while CR during the acute and delayed phases was 75.0% in each cancer group. The antiemetic regimen was well tolerated. Conclusions. A single administration of palonosetron and dexamethasone on day 1 in BC and CRC patients adequately controls CINV during the entire period of emetic risk.