“This is an important study,” said formal discussant Lillian L. Siu, MD, FASCO, Professor, University of Toronto Cancer Care Ontario Research Chair and medical oncologist at Princess Margaret Cancer Centre Drug Development Program in Toronto, Ontario, Canada. “No new drugs have been approved by the U.S. Food and Drug Administration for head and neck cancer since cetuximab.”

“The findings validate the PD-1 (programmed cell death protein 1)/PD-L1 (programmed cell death ligand 1) strategy in relapsed/metastatic head and neck cancer. Additionally, this trial opens up many other opportunities to study this strategy alone or in combination with other therapies,” she told listeners. Clear opportunities for checkpoint inhibitors exist for locally advanced head and neck cancer, in the postoperative setting, locoregionally recurrent disease, and metastatic disease, added Dr. Siu.

It is important to see the survival data regarding prior cetuximab vs no prior cetuximab, shared Dr. Siu. “Also, response rates and progression-free survival data were not presented, and those data would help understand the dynamics of this therapy,” she noted.

The survival curve tail shows that nivolumab has a delayed clinical effect, a phenomenon that has been reported in other studies of PD-1 inhibitors. She pointed out that the rate of 1-year survival with nivolumab is similar to that seen with first-line combination regimens that include cetuximab. “Median overall survival may not be the best readout for nivolumab in this setting because of its delayed activity. One-year survival might be a better endpoint,” Dr. Siu suggested. ■

Disclosure: Dr. Siu reported no potential conflicts of interest.