Patient factors and costs associated with prophylactic neurokinin-1 receptor antagonist use among women with invasive breast cancer

BACKGROUND: In April 2012, the American Society of Clinical Oncology joined the Choosing Wisely (CW) initiative to reduce the use of low-value oncology services. Neurokinin-1 receptor antagonists (NK1-RAs) are a class of expensive antiemetic drugs and are not recommended for patients who receive low to moderate risk emetogenic anticancer agents. OBJECTIVE: To identify patient factors and costs associated with NK1-RAs prophylactic use in a real- world setting post-Choosing Wisely among patients with breast cancer. METHODS: Data Mart Database (2013 to 2018), a retrospective cohort study was conducted for women aged 18 years and older with breast cancer who initiated a low/minimal/moderate emetogenic chemotherapy (index date) and received prophylactic antiemetics 2 weeks prior to the index date through the day after index (N = 18,515). Patients with no claims for antiemetics or who had negative costs were excluded from the costs analysis (n = 12,068). All US Food and Drug Administration-approved NK1-RAs were included. A multivariable logistic regression model was used to assess the association between patient demographic and socioeconomic characteristics, health system and environmental factors, and NK1-RA use, with results presented as adjusted odds ratios (AORs) and 95% CIs. A generalized linear model with gamma distribution and log link and two-part model were used to model mean third-party and out-of-pocket antiemetic-specific costs per patient, respectively, controlling for baseline patient characteristics. RESULTS;: = 0.023), respectively, when compared with those who received NK1-RAs. CONCLUSIONS: Variability in the potential overuse of NK1-RAs was driven by certain patient- (age, race and ethnicity), clinical- (emetic risk), and health care- (insurance, health plan type) related factors. Furthermore, the mean total costs reimbursed by payers were significantly higher for those who received NK1-RAs as compared with other antiemetics, except for those who received both first- and second-generation 5HT3-RAs with or without steroids. Guideline-concordant use of NK1-RAs could result in significant cost-avoidance for patients and payers.