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

BACKGROUND: 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. PATIENTS AND METHODS: 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. RESULTS: 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. CONCLUSIONS: In medically fit older patients, bevacizumab provides similar PFS and OS benefits as in younger patients.