Phase II clinical trial of h-R3 combined radiotherapy for locoregionally advanced nasopharyngeal carcinoma]

BACKGROUND & OBJECTIVE: Anti-epidermal growth factor receptor (EGFR) monoclonal antibodies are easily to produce human anti-murine antibody response at present clinical use. This may influence therapeutic effect. This study was to evaluate the short-term and long-term efficacy and toxicity of the humanized anti-EGFR monoclonal antibody h-R3 in combination with radiotherapy for locoregionally advanced nasopharyngeal carcinoma (NPC). METHODS: Patients with newly diagnosed stage III-IVb (UICC 1997) NPC, who had moderate or strong EGFR expression, were randomized into radiotherapy alone group or radiotherapy combined h-R3 group. Similar dosage and technique of radiotherapy was administered in both groups. The combination group received weekly intravenous infusion of 100 mg h-R3 during radiotherapy. The short-term efficacy was evaluated according to WHO criteria. The survival was analyzed by Kaplan-Meier method. RESULTS: A total of 35 patients were enrolled, 17 in radiotherapy alone group and 18 in combination group. During treatment, only 1 patient withdrew from the combination group. The overall complete remission (CR) rates at the end of treatment, 5 and 17 weeks after treatment were significantly higher in combination group than in radiotherapy alone group (72.2% vs. 35.3%, 83.3% vs. 41.2%, and 83.3% vs. 47.1%, P<0.05). Median follow-up time was 31.9 months (range, 4.2-40.7 months). No significant differences in 3-year locoregional control, distant metastasis-free survival and overall survival rates between the 2 groups were found. Except for 1 patient suffered from grade 2 vomiting, no patient developed other adverse events in combination group. No significant differences in radiotherapy-related adverse events between the 2 groups were observed. CONCLUSIONS: h-R3 is a safe drug which may enhance the response of advanced NPC patients to radiotherapy. However, h-R3 seems not to significantly affect the long-term outcomes.