Design: GRADE-assessed systematic review and meta-analysis (3 RCTs, 1 observational)
Population: 561 patients with metastatic colorectal cancer on FOLFOXIRI-based therapy
Primary outcome: Overall and progression-free survival, response, and toxicity
Effect: OS HR 1.22 (0.78–1.90); PFS HR 1.32 (0.76–2.31); more hypomagnesaemia and rash with cetuximab

FOLFOXIRI with a targeted agent is an intensive first-line option in metastatic colorectal cancer. This GRADE-assessed meta-analysis pooled four studies (three randomised, 561 patients) comparing FOLFOXIRI plus cetuximab with FOLFOXIRI plus bevacizumab.

Neither survival endpoint favoured cetuximab: overall survival hazard ratio 1.22 (95% CI 0.78–1.90) and progression-free survival 1.32 (0.76–2.31), both non-significant, with no difference in response rates. Cetuximab did bring significantly more hypomagnesaemia and acneiform rash.

The practical reading, within the limits of a small pooled sample, is that adding cetuximab rather than bevacizumab to FOLFOXIRI buys no efficacy advantage and costs more toxicity — so bevacizumab is the better-tolerated partner in this specific triplet. It does not speak to cetuximab's established role with doublet chemotherapy in left-sided, RAS wild-type disease, which is a different question.

With FOLFOXIRI, cetuximab gave no better overall or progression-free survival than bevacizumab.
Response rates did not differ between the two combinations.
Cetuximab caused more hypomagnesaemia and acneiform rash.
This concerns the FOLFOXIRI triplet, not cetuximab's role with doublet chemotherapy.

Why it matters

It settles the partner choice for this intensive triplet on tolerability, since efficacy is no different.

The statistics, in plain English

Both hazard ratios sit above 1.0 but their intervals cross it widely, meaning no detectable difference; with only 561 patients the analysis cannot exclude a small effect, but it shows no efficacy edge for cetuximab.