Analysis of a clinical trial finds that nivolumab immunotherapy can be administered safely in conjunction with radiotherapy and chemotherapy for patients with newly diagnosed local-regionally advanced head and neck cancers. The study will be presented at the 2018 Multidisciplinary Head and Neck Cancers Symposium in Scottsdale, Arizona.

All patients in the trial were able to complete curative-intent radiation therapy even with the addition of the PD-1 inhibitor to platinum-based chemotherapy, and maintenance immunotherapy to one year was found to be feasible.

"We previously found that nivolumab improves survival for patients who experience head and neck cancer relapse after platinum chemotherapy. Thus, we are compelled to evaluate whether adding immunotherapy to the initial treatment of head and neck cancer could prevent these relapses from happening," said Maura Gillison, lead author of the study.

"In this trial, we evaluated the safety and feasibility of adding immunotherapy to curative-intent cisplatin and radiation therapy, a treatment that is already quite taxing for patients due to side effects. We found that it is possible to add nivolumab immunotherapy to cisplatin treatment without compromising radiation delivery, and patients were also able to tolerate continuing immunotherapy for up to a year."

The current analysis reports early safety data for the two cohorts who received weekly or high-dose cisplatin chemoradiation therapy. Twenty patients with newly-diagnosed intermediate-risk HNSCC (65% of patients) or high-risk HNSCC (35% of patients) were enrolled.

Median patient age was 56 years (range 35-76), and most patients were male (70%) and Caucasian (85%). Most patients were in advanced stages of disease (80%) and were former smokers (55%).

Patients received nivolumab in addition to chemoradiation with either weekly or high-dose cisplatin. Ten patients were enrolled in each treatment group; eight and nine patients from the weekly and high-dose cohorts, respectively, were evaluable for this analysis.

All patients in both treatment groups completed radiation therapy. Additionally, 15 of 17 patients received at least 70% of their prescribed dose of platinum chemotherapy. Most patients were able to both start and continue nivolumab following first-line treatment.

On the weekly cisplatin arm, 5 of the 8 evaluable patients received 10 doses of concurrent nivolumab and 2 patients received 9 doses. On the high-dose cisplatin arm, 5 of the 9 evaluable patients received 7 doses and 3 patients received 6 doses.

Six of the first 8 patients enrolled in the trial completed a year of nivolumab therapy; other patients in the study continue to receive treatment, but the trial was designed to evaluate the first eight enrolled.

Nivolumab was tolerated well by patients in both treatment groups. No patients in either cohort experienced dose-limiting toxicities, which were defined as grade 3 or higher nivolumab-related adverse events not resolved within four weeks, radiation therapy delays of more than two weeks, or an inability to receive at least 70% of prescribed chemotherapy.

On the weekly cisplatin arm, there was 1 case each of anaphylaxis and cholecystitis, though neither was attributable to nivolumab. Grade 3 side effects attributable to the immunotherapy on this arm included 3 cases of decreased white blood cell count and one case each of fatigue, loss of appetite, lipase elevation, mucositis and adrenal insufficiency.

On the high-dose cisplatin arm, grade 3 side effects related to nivolumab included one case each of diarrhea, lipase elevation and amylase elevation. There were no grade 4 or 5 side effects on either treatment arm.