Durvalumab with or without tremelimumab in patients with recurrent or metastatic head and neck squamous cell carcinoma: EAGLE, a randomized, open -label phase III study

Head and neck squamous cell carcinoma (HNSCC) is among the 10 most common cancers worldwide, with increasing incidence.1 Approximately 10% of patients with HNSCC will be diagnosed with metastatic disease, and even when treated early, around half will have disease recurrence.2,3 The platinum-based doublet chemotherapy with cetuximab regimen has been the most widely-used therapy and considered standard of care (SoC) since it was proven effective in 2007 for recurrent/metastatic (R/M) HNSCC in the first-line setting.3,4 However, patients typically progress even after aggressive first-line therapy, and, until recently, the available options (e.g. cetuximab, methotrexate, and taxanes) have delivered limited survival benefits.3 Durvalumab is an immunotherapeutic agent that blocks the interaction between programmed cell death ligand 1 (PD-L1) and its receptors.5 Durvalumab demonstrated encouraging response rates and duration of response (DoR) with a manageable safety profile in patients with HNSCC.6 Although monotherapy agents that block the programmed cell death protein 1 (PD-1)/PD-L1 axis have shown clinical activity, immunotherapy combinations have the potential to improve upon monotherapy activity.7e9 Cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and PD-L1/PD-1 pathways have largely non-redundant roles, suggesting that blockade of both could have additive or synergistic effects.10 Indeed, the combination of durvalumab and tremelimumab, an anti-CTLA-4 monoclonal antibody, was explored based on improved efficacy over monotherapy in other solid tumor types.7 This observation, in addition to the activity demonstrated by durvalumab in earlier R/M HNSCC studies, served as the rationale to evaluate durvalumab and tremelimumab in patients with R/M HNSCC. Several studies, including the EAGLE study, were initiated to evaluate combination immunotherapy regimens in various patient groups.11,12 The EAGLE study was the first phase III study to investigate durvalumab and tremelimumab in patients with R/M HNSCC who had progressed after platinumbased therapy. During the conduct of the EAGLE study, anti-PD-1 monoclonal antibodies were approved for use for R/M HNSCC progression following a platinum-based regimen. Treatment with these immunotherapies resulted in a median overall survival (OS) of 7.5e8.4 months.13,14 These immunotherapies are now recommended for second-line treatment as monotherapies for patients with R/M HNSCC.3,13,14 More recently, immunotherapy alone or in combination with platinum-based chemotherapy has shown improvements in OS in the first-line setting, underscoring the clinical utility of immunotherapy in HNSCC.15 Here, we report the results of the randomized phase III EAGLE trial evaluating durvalumab and durvalumab plus tremelimumab versus SoC therapies in patients with R/M HNSCC who have progressed following a platinumcontaining regimen.