<p><b>OBJECTIVE</b>To evaluate the efficacy and safty of the humanized anti-epidermal factor receptor monoclonal antibody h-R3 in combination with radiotherapy for locoregionally advanced nasopharyngeal carcinoma.</p><p><b>METHODS</b>Totally, 137 patients from 7 medical center around China were randomly divided into combined therapy group or control group. There was no difference in Karnofsky performance score between two groups. All patients in both groups received radical conventionally fractionated radiotherapy to the total dose of D(T) 70-76 Gy. For the combined therapy group, h-R3 was added at a dose of 100 mg i.v. weekly for 8 weeks started at the beginning of radiotherapy.</p><p><b>RESULTS</b>Of the 137 eligilbe patients, 70 were in the combined therapy group treated by h-R3 plus radiotherapy and 67 in the control group by radiotherapy alone. The intent-to-treat (ITT) population consisted of 130 patients, while the per-protocol (PP) population was composed of 126 patients. The efficacy was assessed respectively at three point of time: the end of treatment, the 5th- and 17th-week after treatment. The complete response (CR) of the combined therapy group was significantly higher than that of the control group in both ITT and PP (ITT: 65.63%, 87.50%, 90.63% versus 27.27%, 42.42%, 51.52%; PP: 67.21%, 90.16%, 93.44% versus 27.69%, 43.08%, 52.31%; P < 0.05, respectively). The most common h-R3-related adverse reactions were fever (4.3%), hypotension (2.9%), nausea (1.4%), dizziness (2.9%) and rash (1.4%), which could be reversible if treated properly. Radiotherapy combined with 100 mg h-R3 i. v. weekly was tolerable and did not aggravate the side effects of radiation. The quality of life in the combined therapy group was comparable to that in the control group.</p><p><b>CONCLUSION</b>This phase 1 multicenter clinical trial shows that h-R3 in combination with radiotherapy is effective and well-tolerated for the treatment of locoregionally advanced nasopharyngeal carcinoma.</p>