Sequential Treatment with Bevacizumab and Aflibercept for Metastatic Colorectal Cancer in Real-World Clinical Practice

Bevacizumab and aflibercept are currently the mainstay of antiangiogenic therapy for metastatic colorectal carcinoma (mCRC). They are often used in sequence with first- and second-line chemotherapy, especially in patients with RAS-mutated tumours. The aim of the present study was to investigate the outcomes of patients with mCRC treated with the bevacizumab-aflibercept sequence in real-world clinical practice. Data from a national clinical registry of targeted therapies for mCRC were analysed retrospectively. Overall, there were 366 patients with valid data who received first-line treatment with bevacizumab and chemotherapy followed by aflibercept with chemotherapy. The majority of the patients (n = 296, 80.8%) had RAS mutated tumours. Median cumulative progression-free survival (PFS) from the start of the bevacizumab-containing regimen to progression on aflibercept was 18.2 months (95% CI 16.8–19.5). Median PFS for bevacizumab and aflibercept was 10.6 months (95% CI 9.5–11.7) and 5.6 months (95% CI 5.1–6.1), respectively. Longer PFS on aflibercept was associated with metachronous metastatic disease and longer PFS on bevacizumab. Median overall survival (OS) from the start of first-line bevacizumab was 32.0 months (95% CI 26.6–37.5). The presence of metastatic disease at diagnosis was associated with worse OS. Patients treated with aflibercept in real-world clinical practice achieved similar survival outcomes as those treated within randomised trials. Cumulative survival data provide a benchmark for future studies and enable indirect comparisons with other treatment sequences used in mCRC.