LAUSR

24Background: Neurokinin-1 receptor antagonists (NK1RA) reduce chemotherapy-induced nausea/vomiting (CINV) among patients undergoing highly emetogenic chemotherapy (HEC). We evaluated factors associated with the use of NK1RA in patients treated with HEC. Methods: We performed a retrospective cohort study using Truven Health Marketscan to identify subjects who initiated HEC (doxorubicin or cisplatin) between 2009 and 2013, and concurrently received a NK1RA. Multivariable logistic regression was used, to determine the association of clinical and demographic factors and NK1RA use. Results: Of 32,004 subjects with cancer who were treated with either doxorubicin or cisplatin-containing regimens, 11,325 (33.3%) did not receive an NK1RA. From 2009 to 2013, NK1RA use increased from 53.2% to 73.5% (p < 0.0001). Compared to non-users, NK1RA users were more frequently treated with cisplatin-based regimens (67.9% vs. 32.1%, p < 0.0001), had in-network claims (66.7% vs. 33.3%, p < 0.0001), were younger, and without ot...