Abstract
PURPOSE: We aimed to evaluate the efficacy of moderate doses of bevacizumab in combination with TAS-102 for the treatment of refractory metastatic colorectal cancer. METHODS: A total of 261 patients with refractory mCRC were enrolled and categorized into two groups: TAS-102 combined with bevacizumab and TAS-102 alone. Patients in the bevacizumab combination group were divided into two subgroups based on a median dose of 3.3 mg/kg. Categorical variables were compared using the chi-square or Fisher's exact test, and continuous variables were assessed using the t-test. The Cox proportional hazards model was used to adjust covariates. Survival analysis was performed using the log-rank test and Kaplan-Meier curves. Specific survival was evaluated using restricted mean survival time (RMST) and landmark analysis. RESULT: The median progression-free survival (PFS) was 3.7 months in the TAS-102 combined with the bevacizumab group and 2.2 months in the non-bevacizumab group, showing significance in favor of the bevacizumab combination. Median overall survival (OS) was 9.4 months in the bevacizumab combination group and 10.3 months in the group that did not receive combination therapy. A survival benefit was observed within 9.5 months in both the RMST and landmark analyses. The PFS benefit was consistent across different doses of bevacizumab, while no significant difference in OS was observed compared to TAS-102 monotherapy. Both PFS and OS did not significantly differ between the different doses of bevacizumab. CONCLUSION: Moderate doses of bevacizumab and TAS-102 provided satisfactory efficacy over the standard dose within a limited timeframe of 9.5 months.