Add-On Nivolumab Extends DFS in Locally Advanced Head and Neck Cancer

CHICAGO – The postoperative addition of nivolumab (Opdivo) to chemoradiotherapy (CRT) extended disease-free survival (DFS) in certain patients with locally advanced head and neck squamous cell carcinoma (HNSCC), according to the NIVOPOSTOP trial.

Patients in the phase III study were at high risk of recurrence, and were not selected for PD-L1 expression. At a median of 30.3 months, patients randomized to nivolumab plus CRT had a 24% improvement in DFS (stratified HR 0.76, P=0.034, 95% CI 0.60-0.98) versus patients who got CRT alone. DFS was the primary endpoint, according to Jean Bourhis, MD, PhD, of Lausanne University Hospital in Lausanne, Switzerland.

Add-on nivolumab represents the first improvement to the standard of care (SoC), which is adjuvant high-dose cisplatin plus RT only, for locally advanced HNSCC in more than 2 decades, said Bourhis at a press briefing at the American Society of Clinical Oncology (ASCO) annual meeting.

He noted that postoperative nivolumab-CRT “could be proposed as a new standard treatment.”

Up to 45% of patients with locally advanced HNSCC will experience recurrence following standard adjuvant cisplatin and RT, “defining an unmet clinical need,” Bourhis said.

PD-1 inhibitors have been established as the SoC for recurrent or metastatic HNSCC. The KEYNOTE-689 trial demonstrated an improvement in event-free survival (EFS) with the addition of neoadjuvant pembrolizumab (Keytruda) followed by adjuvant pembrolizumab to SoC in patients with locally advanced resectable HNSCC. NIVOPOSTOP is the first study to test the efficacy of adjuvant PD-1 inhibition in a population similar to that studied in KENOTE-689.

The current data suggest that moving immune checkpoint inhibition (ICI) to the low-tumor burden setting postoperatively in locally advanced HNSCC is more effective than in the pre- or perioperative setting, said Bourhis. He noted several studies that produced suboptimal results when ICI was used with bulky tumors in place.

NIVOPOSTOP included 680 patients, ages