The purpose of this study was to evaluate the safety and efficacy of cetuximab (C225), an antibody that inhibits epidermal growth factor receptor (EGFR) activity, with cisplatin and to explore associations between EGFR protein expression with patient demographics or clinical outcome.
Women with advanced, persistent, or recurrent carcinoma of the cervix were eligible. The women received cisplatin at 30 mg/m2 days 1 and 8 with a loading dose of cetuximab at 400 mg/m2 followed by 250 mg/m2 days 1, 8, and 15 in a 21 day cycle. Adverse events were assessed with CTCAE v 3.0. Primary measure of efficacy was tumor response by RECIST. The study was stratified by prior chemotherapy (CT). EGFR protein expression in pre-treatment tumor was analyzed by immunohistochemistry.
Between September 2004 and March 2008, 76 patients were enrolled. Of these, 69 were eligible and evaluable; 44 (64%) received prior chemotherapy. There were 4 responses in each group, prior chemotherapy and no chemotherapy, 9% and 16%, respectively. Grade 4 toxicities included anemia (1), allergy (1), metabolic (1), and vascular (1). The most common grade 3 toxicities were metabolic (15), dermatologic (8), fatigue (6), and gastrointestinal (6). EGFR protein was expressed in 47/48 (98%) of tumors analyzed with a median cellular expression of 81%. Exploratory analyses revealed a trend between the percentage of cells expressing EGFR protein and PFS (hazard ratio =1.76, 95% confidence interval=0.96–3.21).
The combination of cetuximab with cisplatin was adequately tolerated but did not indicate additional benefit beyond cisplatin therapy.