Abstract P6-11-11: Single-dose fosaprepitant for the prevention of chemotherapy-induced nausea and vomiting in patients with breast cancer receiving moderately emetogenic chemotherapy regimens

Abstract

Abstract Background: Aprepitant has demonstrated efficacy in patients with breast cancer receiving anthracycline and cyclophosphamide (AC)-based chemotherapy, but the efficacy of single-day fosaprepitant in patients receiving moderately emetogenic chemotherapy (MEC) regimens not including AC has not been widely reported. In a post hoc analysis, we explored prevention of chemotherapy-induced nausea and vomiting (CINV) in a subgroup of patients with breast cancer using a single-day triple-antiemetic fosaprepitant (FA) regimen compared to a standard 3-day control regimen. Methods: This was a global, randomized, double-blind, parallel-group, phase 3 study in adult subjects who were scheduled to receive an intravenous (IV) dose of ≥1 MEC on the first day of treatment (NCT01594749). AC regimens were excluded as they are no longer considered MEC. Subjects were randomly assigned to a control or FA regimen (1:1). The control regimen consisted of oral ondansetron 8 mg, dexamethasone 20 mg, and IV saline as placebo before the first dose of MEC on day 1, and oral ondansetron 8 mg 8 hours after the first dose and every 12 hours on days 2 and 3. The FA regimen consisted of the same dose of oral ondansetron on day 1, along with dexamethasone 12 mg and a single dose of IV FA 150 mg before the first dose of MEC on day 1, with no additional prophylactic antiemetic beyond day 1. The primary end point was complete response (CR; no vomiting or rescue medication) in the delayed phase (25-120 hours after chemotherapy initiation). Results: Overall, 1000 subjects were included in the intention-to-treat population (FA: N = 502; control: N = 498), and the primary end point was met (P < 0.001; FA vs control). In a subset of 231 subjects with breast cancer, 110 received the FA regimen and 121 the control regimen. Subjects were female, with the exception of 1 male in the FA group, most were aged 50 years or older (67%), and 210 subjects (91%) received single-day MEC regimens on day 1. Among them, 17 subjects in the FA group (8.1%) and 27 in the control group (12.9%) received carboplatin-based chemotherapy, and the remaining 166 subjects received other MEC regimens. CR in the delayed phase was achieved by 76.4% of subjects in the FA group and 68.6% in the control group (difference, 7.8%). Approximately 79% in each group had no vomiting episodes in the overall phase (hours 0-120). Completion on study medication was high, at approximately 98% in each group. Adverse events (AEs) were similar between groups: overall AEs occurred in 79.1% and 73.6% of subjects in the FA and control groups, respectively. AEs considered treatment related by the investigator were also balanced by treatment arm, occurring in 14 (12.7%) and 13 (10.7%) subjects in the FA and control groups, respectively; there was 1 treatment-related serious AE (hypersensitivity) that occurred in the FA group. Conclusions: A single-day IV FA regimen is effective for preventing CINV in breast cancer patients receiving MEC. Citation Format: Weinstein C, Jordan K, Green S, Khanani S, Beckford-Brathwaite E, Vallejos W, Pong A, Noga SJ, Rapoport BL. Single-dose fosaprepitant for the prevention of chemotherapy-induced nausea and vomiting in patients with breast cancer receiving moderately emetogenic chemotherapy regimens [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-11-11.