Sequential cetuximab-bevacizumab vs bevacizumab-EGFR mAb shows no DDC difference in metastatic CRC

This phase III randomized controlled trial enrolled 263 patients with untreated, unresectable wild-type RAS/BRAF metastatic colorectal cancer, comparing two sequential treatment strategies. Arm A received FOLFIRI-cetuximab then mFOLFOX6-bevacizumab, while arm B received OPTIMOX-bevacizumab then FOLFIRI-bevacizumab followed by EGFR monoclonal antibody +/- irinotecan, with a median follow-up of 68.4 months (95% CI, 76.5-98.0). The primary outcome was duration of disease control, which showed no difference: 22.8 months in arm A vs 23.5 months in arm B (HR = 1.01; 95% CI, 0.76-1.34; log-rank P = 0.945). Overall survival was 40.4 months in arm A vs 34.4 months in arm B (HR = 1.30; 95% CI, 0.99-1.72), and overall response rates in the first-line group were 82.4% in arm A vs 65.4% in arm B, with second-line rates of 20.7% vs 16.4%, though p-values and absolute numbers for these were not reported.

Safety profiles were consistent with well-known effects of the agents, but serious adverse events, discontinuations, and tolerability details were not reported. Key limitations include that the study did not meet its primary endpoint and is inconclusive in identifying the optimal treatment strategy, with observational aspects requiring cautious interpretation of associations versus causation.

Practice relevance is limited as the evidence does not clearly favor one sequencing approach over the other for this patient population. Clinicians should note the inconclusive findings and consider individual patient factors when selecting treatment sequences, avoiding overstatement of benefits based on surrogate outcomes like response rates without robust clinical endpoint differences.