The combination of adjuvant bevacizumab and capecitabine failed to improve disease-free survival compared with capecitabine alone in patients with metastatic colorectal cancer (mCRC) who had undergone potentially curative surgery, a study published in The Lancet Oncology has shown.1
Previous research has demonstrated that antiangiogenic agents such as bevacizumab are efficacious in the treatment of metastatic colorectal cancer. Therefore, researchers sought to investigate whether adding bevacizumab to capecitabine could improve disease-free survival if given following primary tumor resection.
For the open-label, phase 3 QUASAR 2 trial, investigators enrolled 1952 patients with stage III or high-risk stage II colorectal cancer who had undergone potentially curative surgery. Participants were randomly assigned 1:1 to receive capecitabine on days 1 to 14 of each 3-week cycle with or without bevacizumab on day 1 of each 3-week cycle for 8 cycles.
At a median follow-up of nearly 5 years, results showed that 3-year disease-free survival was 75.4% (95% CI, 72.5-78.0) with bevacizumab and capecitabine vs 78.4% (95% CI, 75.7-80.9) with capecitabine alone (hazard ratio [HR], 1.06; 95% CI, 0.89-1.25; P =.54), suggesting no statistically significant difference between the 2 groups.
Three-year overall survival was also similar between the 2 treatment arms (HR, 1.11; 95% CI, 0.90-1.36; P =.33).
The rates of grade 3 to 4 hand-foot syndrome and diarrhea were similar between the 2 treatment arms, and as expected, all-grade hypertension, proteinuria, and wound healing problems were more common with bevacizumab.
Of note, 15 patients in the combination arm experienced treatment-related death compared with 8 in the capecitabine alone group.
The findings ultimately suggest that bevacizumab should not be added to capecitabine in the adjuvant setting for the treatment of unselected patients with metastatic colorectal cancer. Further studies may be necessary to evaluate this combination in specifically selected patients with certain biomarker profiles.
1. Kerr RS, Love S, Segelov E, et al. Adjuvant capecitabine plus bevacizumab versus capecitabine alone in patients with colorectal cancer (QUASAR 2): an open-label, randomised phase 3 trial. Lancet Oncol. 2016 Sep 20. doi: 10.1016/S1470-2045(16)30172-3. [Epub ahead of print]