The cost of adverse events in metastatic breast cancer in taxane- and capecitabine-based regimens.

Abstract

261 Background: Over 155,000 women are living with metastatic breast cancer (mBC) in the US. Chemotherapies can prolong survival for women with mBC, but adverse events (AEs) stemming from their use are common and costly to manage. We compared the healthcare costs for taxane- (TAX) and capecitabine-based (CAP) treatments for mBCpatients as either first- or second-line (FL or SL) therapy in the US. Methods: Using the Marketscan Commercial Database, a nationally representative database of over 52 million people, we selected mBC patients diagnosed from 2008-2011. Patients were categorized into FL and SL chemotherapy including either a TAX (paclitaxel or docetaxel) or CAP using an algorithm based on pharmacy and medical claims data. Chemotherapy-related AEs were identified by ICD-9 codes. Costs were tabulated from a payer perspective. Average monthly costs were stratified by treatment and the presence/absence of AEs. Results: Among 15,535 mBCpatients we identified 15,472 FL and 6,809 SL cases treated with TAX or CAP. The mean age of patients was 51 years (SD 8). At least one AE was experienced during FL treatment by 74% (SD 44%) and 68% (SD 46%) of TAX and CAP users and during SL treatment 60% (SD 49%) and 59% (SD 49%), respectively. Average monthly total costs during the FL period were $2,385 higher (p <0.0001) and $1,679 higher (p=0.28) for TAX- and CAP-treated patients who experienced at least one AE. In SL, costs for patients with at least one AE had were $2,995 (p<0.0001) higher for TAX-treated patients and $4,870 (p=0.0026) higher for CAP-treated patients. Conclusions: Among community-treated patients, AEs are common in women with mBC receiving TAX- and CAP-based chemotherapy regimens. These AEs are associated with higher costs in FL and SL. When possible, prevention or earlier management of AEs may represent an opportunity to reduce costs and improve outcomes for women with mBC. [Table: see text]