Comparison of two dosing schedules of palonosetron for the prevention of nausea and vomiting due to interleukin-2-based biochemotherapy.

Background: Treatment of metastatic melanoma with interleukin-2-based biochemotherapy involves administration of a combination of moderately and highly emetogenic chemotherapies over 5 days. Corticosteroids for the prevention of biochemotherapy-induced nausea and vomiting (CINV) are contraindicated because they cause lysis of LAK cells produced in response to interleukin-2. Palonosetron is a long-acting, highly potent, second-generation serotonin receptor antagonist. The recommended dosing schedule of palonosetron for the control of CINV due to biochemotherapy is not known.

Methods: In a phase II design, treatment-naïve patients with metastatic melanoma undergoing the first cycle of biochemotherapy were randomized to receive palonosetron 0.25 mg intravenously for CINV prophylaxis on either days 1 and 4 (schedule 1) or days 1, 3, and 5 (schedule 2). All patients received dacarbazine on day 1, cisplatin, vinblastine, and interleukin-2 on days 1-4, and interferon alpha-2b on days 1-5. We evaluated and compared, by palonosetron dosing schedule, the pattern and the severity of CINV during the first 7 days of treatment and the duration of the 21-day cycle as well as the impact on daily function with the Functional Living Index-Emesis.

Results: Thirty patients (median age 53 years) were enrolled. Eighteen (60%) were men. A consistent trend of a better control of both nausea and vomiting favoring schedule 2 was observed during the first 7 days and throughout the cycle. Significantly more patients experienced nausea on any day during the first 7 days on schedule 1 (mean number of episodes 8.1 ± 1.5) than on schedule 2 (mean number of episodes 5.6 ± 2.3, p = 0.028). The impact on daily function was similar between the two groups.

Conclusions: Both dosing schedules of palonosetron were tolerated well. Alternate day dosing of palonosetron was more effective in controlling CINV in this patient population.