Phase II study of dalantercept, a novel inhibitor of ALK1-mediated angiogenesis, in patients with recurrent or metastatic squamous cell carcinoma of the head and neck.

TPS6098 Background: Despite advances in the treatment of recurrent or metastatic squamous cell carcinoma of the head and neck (SCCHN), the prognosis remains poor with a need to develop novel therapeutic strategies. Targeting angiogenesis in SCCHN is an active area of clinical research. Activin receptor-like kinase 1 (ALK1) is a type 1 receptor in the TGF-s superfamily which is selectively expressed on activated endothelial cells. ALK1 binds bone morphogenetic proteins (BMP) 9 and 10 (ligands for ALK1) and is primarily involved in the maturation stage of angiogenesis. Dalantercept is a human ALK1-Fc receptor fusion protein that binds BMP9/10 and acts as a ligand trap. In preclinical tumor models, dalantercept demonstrated a decrease in tumor vascularization and delayed tumor growth. In a completed phase I study, dalantercept demonstrated anti-tumor activity in patients with advanced solid tumors including SCCHN. Methods: An open label, multi-center, multiple dose, phase II study to evaluate dalantercept in...