Phase II, randomized, open-label study of durvalumab (MEDI4736) or tremelimumab monotherapy, or durvalumab + tremelimumab, in patients with recurrent or metastatic (R/M) squamous cell carcinoma of the head and neck (SCCHN): CONDOR

Background First-line palliative treatment for patients with R/M SCCHN includes platinum-based chemotherapy. There are no standard second-line options upon relapse and median survival is limited. In SCCHN, tumors create a highly immunosuppressive environment and evade immune detection by exploiting inhibitory immune checkpoints such as the programmed cell death ligand-1 (PD-L1)/programmed cell death-1 (PD-1) axis, making immunotherapy an attractive option to study in this disease. Durvalumab (MEDI4736) is a selective, high affinity human IgG1 mAb that blocks PD-L1 binding to PD-1 (IC50 0.1 nM) and CD80 (IC50 0.04 nM) that has shown promising antitumor activity in the SCCHN cohort of a Phase I/II study (NCT01693562). Tremelimumab is a selective human IgG2 mAb inhibitor of cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) that has been combined with durvalumab in a Phase Ib study in patients with NSCLC (NCT02000947), with encouraging clinical activity and a manageable safety profile. While anti-PD-1/PD-L1 monotherapy may be associated with greater clinical benefit in patients with PDL1 tumors, combination therapy has clinical activity in both PD-L1 and PD-L1 patients in several solid tumors, enhancing the antitumor activity of anti-PD-1/PD-L1 agents in patients with PD-L1 tumors. The PD-L1 and CTLA-4 pathways are non-redundant and preclinical data indicate targeting both may induce synergistic antitumor effects. Here we describe the CONDOR study (NCT02319044), a Phase II study to determine the efficacy and safety of durvalumab monotherapy, tremelimumab monotherapy, and their combination in PD-L1 R/M SCCHN patients who have failed prior platinumtherapy.