Novel Monoclonal Antibody Plus Cetuximab Under Study in Head/Neck Cancer
Posted: Wednesday, August 14, 2019
An open-label phase II study showed that the combination of cetuximab and CDX-3379, an anti-ErbB3 monoclonal antibody, is well tolerated by patients and has antitumor activity in patients with head and neck squamous cell carcinoma. The study was presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago (Abstract 6025) by Julie E. Bauman, MD, MPH, of the University of Arizona Cancer Center. CDX-3379 works by binding a unique epitope to lock ErbB3 in an inactive form, thereby inhibiting the ErbB3 signaling that has been implicated in tumor growth.
Patients enrolled in this study had advanced human papillomavirus–negative squamous cell carcinomas that were previously treated with cisplatin, anti–PD-1 antibodies, and cetuximab. A total of 14 patients were treated with 12 mg/kg of CDX-3379 every 21 days plus cetuximab (400 mg/m2 loading dose, 250 mg/m2 intravenously weekly) until disease progression.
All patients included in the study had been heavily treated with some combination of prior therapies such as chemotherapy, surgery, radiation, cetuximab, and PD-1–targeted therapy. At the time of study presentation, 1 of 14 patients had a confirmed complete response to treatment for 8.1+ months . In addition, 7 of 14 patients had stable disease, and 4 of them had tumor shrinkage (8.0%–27.5% reduction in size). Three patients have continued treatment.
Adverse events related to the treatment protocol were typically grade 1 or 2. The most common side effects were diarrhea (53%), hypokalemia (20%), prolonged QT interval (13%), and rash (13%).
Disclosure: The study authors’ disclosure information may be found at coi.asco.org.