Economic burden of common adverse events (AEs) associated with metastatic colorectal cancer (mCRC) treatment in the United States (US).

21 Background: Treatments for mCRC have distinct safety and tolerability profiles. Common AEs associated with mCRC treatments may compromise the course of treatment, worsen quality of life, and increase healthcare resource utilization and costs. This study assessed the costs of common AEs in mCRC patients (pts) in the US.

METHODS: Adult mCRC pts treated with chemotherapy (chemo) or targeted therapies were identified from the Truven MarketScan databases (2009 - 2014). Up to the first 3 mCRC treatment episodes were considered. mCRC treatment episodes were categorized as with or without (w/o) AEs based on the occurrence of AEs, listed in product labels, during the episode. Total healthcare costs (medical and pharmacy; 2014 USD) were measured by mCRC treatment episode and reported per-patient-per-month (PPPM). mCRC treatment episodes with AEs were matched by type of treatment (monotherapy/combination, chemo, anti-VEGF, and anti-EGFR) and line of therapy to those w/o AEs. Adjusted total cost differences were estimated by comparing costs during mCRC treatment episodes with vs w/o AEs using multivariate two-part models, adjusting for potential confounding factors; 95% confidence intervals (CIs) and p-values were estimated with bootstrap.

RESULTS: A total of 4,158 mCRC pts with ≥ 1 mCRC treatment episode were included (mean age= 59 years; 58% male; 2261 [54%] with a 2(nd) and 1115 [27%] with a 3(rd)episode). The most prevalent metastatic sites were liver (60%) and lung (14%). On average, 2 mCRC treatment episodes were observed per patient with an average length of 166 days per episode. Most mCRC treatments included chemo (96%) and were combination regimens (81%).

CONCLUSIONS: The most costly AEs were hematologic, followed by respiratory, CNS, cardiovascular, and endocrine/metabolic AEs in mCRC pts. [Table: see text].