Objective: To compare the health care costs of patients with metastatic colorectal cancer (mCRC) who received second-line treatment with Avastin (bevacizumab) versus Erbitux (cetuximab), from the third-party payer's perspective.
Methods: Patients with mCRC were selected from the PharMetrics claims database if they received second-line therapy containing either bevacizumab (second-line bevacizumab cohort) or cetuximab (second-line cetuximab cohort). Six-month costs following second-line therapy start date and average monthly healthcare costs while on second-line therapy (in 2009 US$) were calculated and compared between the two groups.
Results: A total of 2188 patients with mCRC who met the eligibility criteria were included in the analysis, including 1808 patients receiving bevacizumab and 380 patients receiving cetuximab in second-line treatment. Demographic and baseline characteristics were similar between the two groups. Patients' mean age was 61 years and 56% were males. In second-line treatment, bevacizumab was commonly used with oxaliplatin (43.5%) and irinotecan-based regimens (40.4%), whereas cetuximab was commonly used with irinotecan-based regimens (68.2%). Bevacizumab patients had significantly lower total all-cause healthcare costs than cetuximab patients (adjusted difference: -$10,231, p = 0.020), and lower medical costs (-$10,796, p = 0.012) during the 6 months following second-line therapy initiation. Approximately half of the difference in total all-cause healthcare costs was attributable to the lower chemotherapy and targeted therapy costs (-$5635, p = 0.032) of bevacizumab patients than those of cetuximab patients. While on second-line therapy, bevacizumab patients also had lower average monthly all-cause healthcare costs than cetuximab patients.
Limitations: Second-line treatment in the current study was defined based on changes in mCRC medications, not based on disease progression due to the limited clinical information available in claims.
Conclusion: The use of bevacizumab in second-line therapy was associated with significantly lower healthcare costs in mCRC patients, compared to the use of cetuximab.