Preoperative nivolumab, with or without ipilimumab, appeared safe and effective in a phase 2 trial of patients with oral cavity squamous cell carcinoma (OCSCC).
“We found that nivolumab, with or without ipilimumab, was feasible prior to surgery in patients with oral cavity cancers, with no delays in surgery observed,” said Jonathan D. Schoenfeld, MD, of the Dana-Farber/Brigham and Women’s Cancer Center in Boston.
“We did observe promising rates of volumetric and pathologic response, with near-complete and complete responses observed, particularly in the nivo-ipi arm.”
Dr. Schoenfeld presented these results at the Multidisciplinary Head and Neck Cancer Symposium, sponsored by the American Society for Radiation Oncology.
“The rationale behind evaluation of neoadjuvant immunotherapy is the potential of tumor downstaging, converting unresectable disease to resectable and inducing durable immunological memory as a result of exposure to the full breadth of tumor antigens preoperatively,” said Kartik Sehgal, MD, of Beth Israel Deaconess Medical Center in Boston, who was not involved in this study.
“This randomized, phase 2 window study ... found that treatment with two neoadjuvant cycles of nivolumab alone or along with ipilimumab during the first cycle was feasible from an adverse events perspective and led to volumetric responses in approximately 50% of patients.”
Patients and treatment
The trial (NCT02919683) enrolled 30 patients with OCSCC, but 1 patient was excluded due to metastases at baseline. Patients had T2 (n = 20) or greater (n = 9) disease at baseline, and 58% of patients (n = 17) had node-positive disease.
The patients were randomized to two cycles of nivolumab (3 mg/kg) or nivolumab (3 mg/kg) plus ipilimumab (1 mg/kg with the first cycle). Patients underwent surgery 3-7 days after completing cycle 2.
In the nivolumab monotherapy arm (n = 14), the median age was 64.4 years (range, 39.1-81 years), and 71.4% of patients were men. Oral tongue was the primary tumor site in 50% of patients, and 50% of patients had stage IV disease.
In the nivolumab-ipilimumab arm (n = 15), the median age was 65.2 years (range, 32.5-78.4 years), and 53.3% of patients were men. Oral tongue was the primary tumor site in 60% of patients, and 73.3% of patients had stage IV disease.
Safety and tolerability
Six patients did not receive the full cycle 2 dose of immunotherapy, two in the nivolumab arm and four in the nivolumab-ipilimumab arm. This was most commonly due to an infusion reaction during cycle 2, Dr. Schoenfeld said.
There were no cases in which surgery was delayed. However, one patient did have surgery moved to an earlier date after cycle 1 because of concerns about progression.
There were three severe immune-related adverse events. In the nivolumab-ipilimumab arm, there was a case of grade 3 pneumonitis and a case of grade 3 colitis. Both of these events were reversible with treatment.
In the nivolumab monotherapy arm, one patient had grade 4 new-onset diabetes with diabetic ketoacidosis. This patient is still insulin dependent.
Perioperative adverse events in both arms included pulmonary embolism, postoperative hematoma, and flap failures (n = 2). One patient with flap failure also had a perioperative stroke, experienced progressive clinical decline, and ultimately died.