Study Will Evaluate Panitumumab Regimen in Advanced SCCHN

Canadian researchers are investigating standard fractionation radiotherapy with concurrent high-dose cisplatin versus accelerated fractionation radiotherapy with panitumumab in patients with locally advanced stage III and IV squamous cell carcinoma of the head and neck (SCCHN).

The NCIC Clinical Trials Group has completed accrual for the randomized phase III study, which has a planned sample size of 320 patients with SCC of the oral cavity, oropharynx, larynx, or hypopharynx. The trial was launched in December 2008, and the Data Safety and Monitoring Committee recommended continuing the trial in October 2011.

Patients assigned to arm I will undergo standard fractionation radiotherapy once daily, five days a week, for seven weeks; they will also receive cisplatin intravenously over one hour on days 1, 22, and 43 of radiotherapy.

Participants assigned to arm II will undergo accelerated fractionation radiotherapy once or twice daily, five days a week, for six weeks; they will also receive panitumumab intravenously over 30-90 minutes one week prior to and on days 15 and 36 of radiotherapy.

The primary endpoint is progression-free survival (PFS), while secondary endpoints include overall survival, local and regional PFS, distant metastases, adverse events, swallowing-related quality of life, functional swallowing outcomes, and economic assessments.

The FDA has approved panitumumab under the brand name Vectibix for the treatment of patients with metastatic colorectal carcinoma with disease progression on or following chemotherapy regimens containing fluoropyrimidine, oxaliplatin, and irinotecan. Panitumumab is a human IgG2 kappa monoclonal antibody that binds specifically to human epidermal growth factor receptor (EGFR).

Amgen, which markets Vectibix, has joined the Canadian Cancer Research Society Institute in supporting the trial (NCT00820248).

Waldron JN, Parulekar W, O’Sullivan B, et al. A phase III study of standard fractionation radiotherapy with concurrent high-dose cisplatin versus accelerated fractionation radiotherapy (RT) with panitumumab in patients with locally advanced stage III and IV squamous cell carcinoma of the head and neck (SCCHN) (NCIC Clinical Trials Group HN.6). J Clin Oncol. 2012;30(suppl; abstr TPS5600).