Nivolumab Plus Ipilimumab Fails to Overcome Immunotherapy Resistance in Head and Neck Squamous Cell Carcinoma

Clinical Summary: 

• Design/Population: The randomized phase 2 OPTIM study evaluated nivolumab plus ipilimumab versus docetaxel in patients with head and neck cancer who had failed to respond to nivolumab monotherapy.
• Key Outcomes: Adding ipilimumab to nivolumab did not produce objective responses and was associated with limited progression-free and overall survival. Docetaxel demonstrated greater clinical activity, including an objective response rate of approximately 18% and longer progression-free and overall survival.
• Clinical Relevance: These findings suggest that escalating checkpoint inhibition does not overcome primary resistance to nivolumab and underscore the need for novel therapeutic strategies targeting mechanisms of immune resistance in head and neck cancer.

Viktor Grünwald, MD, PhD, University Hospital Essen, Germany, discusses results from the phase 2 OPTIM study evaluating nivolumab plus ipilimumab versus docetaxel in patients with head and neck cancer who failed to respond to nivolumab monotherapy. 

Results demonstrated that adding CTLA-4 blockade did not overcome resistance to nivolumab, whereas chemotherapy demonstrated greater clinical activity. Dr Grünwald discusses how these findings highlight the limitations of escalating immune checkpoint blockade after immunotherapy resistance and the need to identify novel mechanisms and treatment combinations capable of restoring antitumor activity. 

Transcript: 

Hello, my name is Viktor Grünwald, I'm medical oncologist from the University Hospital in Essen, Germany. It really is a great privilege for me to present key topics of the OPTIM study, an academic study that was performed within the AIO network within Germany.

What we were interested in was really to address the question in head and neck cancers whether treatment with nivolumab and ipilimumab in patients that failed to respond to nivolumab single agent was really of benefit. We did it in a randomized phase 2 session, randomizing patients that failed nivolumab treatment towards an escalated immunotherapy, adding ipilimumab, or patients were randomized and received conventional chemotherapy, docetaxel. I think that's something that is considered in most of the patients, at least, a standard of care in later lines of treatment. 

The key finding was really that this escalated immunotherapy did not really rescue patients. Patients that have been treated with ipilimumab and nivolumab had no response, no objective response. Also, progression-free survival (PFS) was quite low, about 2 months of PFS, and overall survival was low as well. Compared to the chemotherapy arm, there were 18% objective responses, about 3.6 months of progression-free survival, and 12 months of overall survival.

What we have shown was the opposite of what we intended to do. We have seen that chemotherapy in immunotherapy non-responders was more effective than an escalated immune strategy, indicating that this may not be the best way to really address this immune resistant phenotype in head and neck cancer patients. 

Our study was quite small because we stopped therapy early because of the change of the treatment landscape and availability of other immune agents in the first line setting, I think it was tough to perform the study during these times– that's why we really stopped it early.

With all those limitations in mind, I think what we really have seen is that when it comes to immune resistant disease, we have to have novel agents to be included because chemotherapy, although it was more effective than our strategy, was still a low performer and did not really have a high impact on survival and treatment activity in patients basically. 

It is important to understand what the driver of resistance is and come up with novel mechanisms of action that really can convert immunotherapy non-responders into responding patients. That's the future approach, although it is difficult to find the right combinations. I think that's what we will envision in the future in this specific disease setting.

Source: 

Grünwald V, Alt J, Tometten M, et al. OPTIM: A randomized phase II trial of nivolumab followed by nivolumab-ipilimumab or docetaxel at progression in recurrent/metastatic squamous cell carcinoma of the head and neck (OPTIM; AIO-KHT-0117). Br J Cancer. Published online: July 18, 2026. doi: 10.1038/s41416-026-03558-z