Efficacy of a triple antiemetic regimen with aprepitant for the prevention of chemotherapy-induced nausea and vomiting: effects of gender, age, and region

Objective: To determine the variability in treatment responses to antiemetic therapy (ondansetron and dexamethasone vs ondansetron and dexamethasone plus aprepitant) given with moderately emetogenic chemotherapy. Research design and methods: Post hoc subgroup analysis of data from a phase III, randomized, double-blind clinical trial evaluated whether the efficacy of aprepitant triple therapy (ondansetron and dexamethasone plus aprepitant) versus control (ondansetron and dexamethasone) varies by gender, age, or region in 848 men and women >= 18 years old with histologically confirmed malignancies and who were naive to moderately or highly emetogenic chemotherapeutic agents. Endpoints compared were the incidences of no vomiting, complete response, and no use of rescue therapy, all during the overall period (0-120 h). Main outcome measures: Regardless of age, gender, or region, the aprepitant regimen provided better control for the no-vomiting and complete-response (no vomiting, no rescue therapy) endpoints. Results: The aprepitant regimen provided better control for the no-vomiting and complete-response (no vomiting, no rescue therapy) endpoints. Overall response rates were higher in men and in older (>= 55 y) patients, but treatment differences were greater among women and younger patients, known to be at increased chemotherapy-induced nausea and vomiting (CINV) risk. Aprepitant showed a benefit versus control across regions, although the between-treatment difference appeared to be smaller for patients in Central/South America versus North America or international regions. Conclusions: Although we acknowledge that subset numbers in this post hoc analysis may be too small to allow definitive conclusions, the data suggest that aprepitant triple therapy provides a benefit over control therapy for the prevention of CINV in patients receiving anthracycline and cyclophosphamide (AC)-or non-AC-based moderately emetogenic chemotherapy across age, gender, and region.