Background:

This single-arm phase II study investigated the EGFR monoclonal antibody necitumumab plus modified FOLFOX6 (mFOLFOX6) in first-line treatment of locally advanced or metastatic colorectal cancer (mCRC).

Methods:

Patients received 800-mg intravenous necitumumab (day 1; 2-week cycles), followed by oxaliplatin 85 mg m− 2, folinic acid 400 mg m− 2, and 5-fluorouracil (400 mg m− 2 bolus then 2400 mg m− 2 over 46 h). Radiographic evaluation was performed every 8 weeks until progression. Primary endpoint was objective response rate.

Results:

Forty-four patients were enrolled and treated. Objective response rate was 63.6%(95% confidence interval 47.8–77.6); complete response was observed in four patients; median duration of response was 10.0 months (7.0–16.0). Median overall survival (OS) and progression-free survival (PFS) were 22.5 (11.0–30.0) and 10.0 months (7.0–12.0), respectively. Clinical outcome was better in patients with KRAS exon 2 wild type (median OS 30.0 months (23.0–NA); median PFS 12.0 (8.0–20.0)), compared with KRAS exon 2 mutant tumours (median OS 7.0 months (5.0–37.0); median PFS 7.0 (4.0–18.0)). The most common grade⩾ 3 adverse events were neutropenia (29.5%), asthenia (27.3%), and rash (20.5%).

Conclusion:

First-line necitumumab+ mFOLFOX6 was active with manageable toxicity in locally advanced or mCRC; additional evaluation of the impact of tumour RAS mutation status is warranted.