A recent study published in Scientific Reports has revealed that bevacizumab, when combined with FOLFIRI chemotherapy, demonstrates superior overall survival (OS) compared to aflibercept in patients with RAS wild-type metastatic colorectal cancer (mCRC). The research, which retrospectively analyzed data from patients who had previously progressed on FOLFOX and bevacizumab, highlights important considerations for second-line treatment strategies in this patient population.
The study included 243 patients, with 129 receiving bevacizumab and 114 receiving aflibercept in combination with FOLFIRI. The median age of patients was 60 years, and the majority (87.2%) presented with de novo metastatic disease. The primary objective was to compare the OS and progression-free survival (PFS) between the two treatment arms.
Key Findings on Survival Rates
The results indicated a statistically significant difference in OS, with a median of 14.2 months (95% CI: 11.2–17.2) in the bevacizumab arm compared to 11.2 months (HR: 0.68, 95% CI: 9.2–13.3) in the aflibercept arm (p = 0.006). Similarly, the median PFS was 7.7 months (95% CI: 7.1–8.3) in the bevacizumab arm and 5.7 months (HR: 0.66, 95% CI: 4.9–6.6) in the aflibercept arm (p = 0.003).
Prognostic Factors and Treatment Discontinuation
Multivariable analysis identified tumor localization (p = 0.037), albumin value (p = 0.003), and the choice of second-line treatment (p = 0.031) as independent risk factors affecting OS. The study also examined reasons for treatment discontinuation, noting that a higher percentage of patients in the bevacizumab arm completed treatment (24.8%) compared to the aflibercept arm (13.2%). Disease progression was the primary reason for discontinuation in both groups, while toxicity led to discontinuation in 13.2% of aflibercept-treated patients and 9.3% of bevacizumab-treated patients.
Adverse Events
The most frequently observed side effects in both arms were neutropenia (26.3% in aflibercept arm and 25.6% in bevacizumab arm), diarrhea (24.5% and 23.3%, respectively), and fatigue-asthenia (14.0% and 17.1%, respectively). Grade 3–4 side effects were more common in the aflibercept arm (50.9%) compared to the bevacizumab arm (25.6%).
Implications for Clinical Practice
These findings suggest that bevacizumab may be a more effective second-line treatment option than aflibercept for patients with RAS wild-type mCRC who have progressed on first-line FOLFOX and bevacizumab. The study underscores the importance of considering individual patient characteristics, such as tumor location and albumin levels, when making treatment decisions. Further research is warranted to validate these findings and explore the underlying mechanisms driving the observed differences in survival outcomes.
