Background: Preclinical studies suggest that insulin-like growth factor-1 receptor (IGF-1R) blockage could be a promising therapeutic target in squamous cell carcinoma of the head and neck (SCCHN). Therefore, we investigated the efficacy and toxicity of figitumumab, an anti-IGF-1R monoclonal antibody, in palliative SCCHN.
Patients and methods: Patients with palliative SCCHN progressing after platinum-based therapy were treated with figitumumab i.v. 20 mg/kg, every 3 weeks. The primary end point was the disease control rate at 6-8 weeks after treatment initiation. Tumor biopsies and plasma samples were collected before and after figitumumab administration to monitor the molecular response.
Results: Seventeen patients were included. Only two patients achieved stable disease at 6-8 weeks. Median overall survival and progression-free survival were 63 and 52 days, respectively. The main grade 3-4 adverse event was hyperglycemia (41%). Translational research showed that figitumumab downregulated IGF-1R at the surface of tumor cells with activation of the epidermal growth factor receptor (EGFR) pathway, as shown by the upregulation of p-EGFR in tumor cells (P=0.016), and an increase in the plasma level of tumor growth factor-alpha (P=0.006).
Conclusion: Figitumumab monotherapy has no clinically significant activity in unselected palliative SCCHN.