Effect of bevacizumab in older patients with metastatic colorectal cancer: pooled analysis of four randomized studies

Bevacizumab is frequently combined with 5-fluorouracil-based chemotherapy for patients with metastatic colorectal cancer (mCRC). The relative benefit of bevacizumab in older patients has not been widely studied and is of interest. This retrospective analysis used data from three first-line randomized controlled studies and one second-line randomized controlled study of bevacizumab plus chemotherapy in medically fit (Eastern Cooperative Oncology Group performance status 0 or 1) patients with mCRC. Overall survival (OS) and on-treatment progression-free survival (PFS) were assessed in patients aged <65, ≥65, and ≥70 years. Results were compared using unstratified hazard ratios (HRs). Grade 3–5 adverse events were also assessed. Bevacizumab statistically significantly improved PFS [HR 0.58; 95% confidence interval (CI) 0.49–0.68] and OS (HR 0.85; 95% CI 0.74–0.97) in patients aged ≥65 years; patients aged ≥70 years had similar improvements. Benefits were consistent across the studies, irrespective of setting, bevacizumab dose, or chemotherapy regimen. Increases in thromboembolic events were observed in patients aged ≥65 and ≥70 years in the bevacizumab group compared with the control group, mainly as a result of increases in arterial thromboembolic events. No other substantial age-related increases in grade 3–5 adverse events were observed. In medically fit older patients, bevacizumab provides similar PFS and OS benefits as in younger patients