Astro’s Interpretation of the Phase II CONDOR trial suggests that the immune checkpoint inhibitor durvalumab is tolerable among heavily pre-treated patients with recurrent or metastatic head and neck cancer and has the potential to slow growth in tumors with low or negative expression of the PD-L1 protein. PriorPhase II HAWK trial exhibited the safety and efficacy of durvalumab monotherapy in head and neck tumors that express high levels of PD-L1. Durvalumab showed encouraging anti-tumor activity both alone and in combination with tremelimumab
Cancerous cells produce proteins to stop the body’s natural immune response to recognize and respond to the disease. Immune checkpoint inhibitors such as durvalumab are designed to block these so-called “checkpoint” proteins—thus allowing the immune system to remain active and attack tumors more successfully.
Lillian Siu, MD, lead author of the study, as well as a senior medical oncologist at Princess Margaret Cancer Centre and a professor of medicine at the University of Toronto said “Two immunotherapies have already been approved for use in platinum-refractory recurrent or metastatic head and neck cancer, but not all patients respond to these therapies. For immunotherapy to increase its clinical utility, it’s important that we can better identify the patients who will most likely respond to treatment.”
Data based on extrapolation of 267 patients with metastatic (64% of patients) or recurrent (36%) cancer of the oral cavity, oropharynx, hypopharynx or larynx who had not responded to prior platinum-based chemotherapy, and who had low or negative expression of the PD-L1 protein. Patients were stratified by HPV and smoking status and randomized to one of three treatment arms: durvalumab alone (10 mg/kg, IV Q2W) (67 patients); tremelimumab alone (10 mg/kg IV Q4W ×7 then Q12W ×2) (67 patients); or durvalumab plus tremelimumab ([20 mg/kg D Q4W + 1 mg/kg T Q4W] ×4 then 10 mg/kg D Q2W) (133 patients).