Phase II Study of Cetuximab Plus Concomitant Boost Radiotherapy in Japanese Patients with Locally Advanced Squamous Cell Carcinoma of the Head and Neck

BACKGROUND: We investigated the tolerability of cetuximab plus radiotherapy in Japanese patients with untreated locally advanced squamous cell carcinoma of the head and neck. METHODS: Patients with epidermal growth factor receptor-expressing locally advanced squamous cell carcinoma of the head and neck received cetuximab (400 mg/m(2) initial dose then 250 mg/m(2) weekly) for 7 weeks plus concomitant boost radiotherapy (weeks 2–7: once daily [1.8 Gy] for 3.6 weeks, then twice daily [1.8 Gy morning and 1.5 Gy afternoon] for 2.4 weeks). The primary endpoint was treatment completion rate (the rate of treated patients completing ≥70% of the planned cetuximab dose and the full dose of radiotherapy within 2 weeks over the planned schedule). RESULTS: Twenty-two patients were evaluable. The treatment completion rate was 100% (95% confidence interval 85–100). The response rate 8 weeks post-radiotherapy was 82% (95% confidence interval 60–95). The most common grade 3/4 treatment-emergent adverse events were mucosal inflammation (73%); dermatitis (27%); and infection, radiation skin injury and stomatitis (23% each). CONCLUSIONS: Cetuximab plus concomitant boost radiotherapy can be safely administered to Japanese patients with locally advanced squamous cell carcinoma of the head and neck. Tolerability and efficacy were in line with those reported in the Phase III Bonner trial in a Western population of patients with locally advanced squamous cell carcinoma of the head and neck.