Adding nivolumab to chemoradiotherapy after surgery can decrease the chance of recurrence in patients with locally advanced head and neck squamous cell carcinoma, according to findings from the international phase III NIVOPOSTOP trial. This study is one of the first to show an improvement in the standard of care for these patients in more than 20 years. The research is being presented during the Plenary Session at the 2025 ASCO Annual Meeting (Abstract LBA2).
“The outcome for patients with locoregionally advanced head and neck cancers remains generally poor, with only 50% to 55% of patients free of disease at 3 years when treated with standard of care,” noted lead study author Jean Bourhis, MD, PhD, of Lausanne University Hospital in Lausanne, Switzerland. “There is clearly a need for more effective and also well-tolerated treatments. We have been trying for more than 20 years to improve this standard of care.”
About half of people with locoregionally advanced head and neck cancer will have their cancer removed surgically, after which those at high risk of recurrence will receive chemoradiotherapy. However, the cancer returns in up to 50% of patients who receive this treatment.
Study Details
NIVOPOSTOP examined whether adding nivolumab to chemoradiotherapy after surgery could help delay cancer recurrence in patients with locoregionally advanced head and neck cancer. Researchers looked at data accrued from 666 of the 680 enrolled participants. To be included in the trial, patients had to be younger than 75 years and have locoregionally advanced head and neck cancer. In addition, patients had to be identified as having a high risk of recurrence following surgery.
Patients were randomly assigned to one of two treatment groups postsurgery. Group A (n = 334) received chemoradiotherapy (66 Gy of radiation plus cisplatin) every 3 weeks for three cycles. Group B (n = 332) received an initial dose of nivolumab, followed by nivolumab plus chemoradiotherapy every 3 weeks for three cycles, followed by six cycles of nivolumab alone every 4 weeks.
Key Findings
At a median follow-up of 30.3 months, 252 of the 666 patients in the trial experienced a recurrence or had died. The researchers found that the odds of disease-free survival were 24% higher in patients who received nivolumab with chemoradiotherapy. In patients who received nivolumab, 63.1% had no signs of cancer recurrence 3 years after treatment vs 52.5% of patients who received chemoradiotherapy alone.
More serious side effects were observed in the patients who received nivolumab. In the 100 days following treatment, 13.1% of patients who received nivolumab with chemoradiotherapy experienced a grade 4 adverse event vs 5.6% who received chemoradiotherapy alone. The most common grade 4 adverse events in both groups were neutropenia and lymphocytopenia.
The investigators plan to share updated survival data when prescribed mortality numbers are reached, likely in 2026 or 2027.
Conclusion
The researchers concluded, “Adjuvant [nivolumab] added to [cisplatin radiotherapy] after surgery provided a statistically and clinically meaningful [disease-free survival] improvement in PD-L1 all-comers patients. This is the first time in over 2 decades that a therapy demonstrated superiority over [standard-of-care cisplatin-chemoradiotherapy] in patients with resected [locally advanced head and neck squamous cell carcinoma] at high risk of relapse.”
Disclosure: This study was funded by Bristol Myers Squibb and GORTEC. For full disclosures of the study authors, visit coi.asco.org.
