A phase II, open label, multicenter trial of avelumab in patients with advanced, metastatic high-grade neuroendocrine carcinomas NEC G3 (WHO 2010) progressive after first-line chemotherapy (AVENEC).

4103 Background: High grade Neuroendocrine Neoplasias (NEN) are rare tumors with a poor prognosis and no established second line therapy when progressive after first line platinum-based chemotherapy resulting in a median overall survival (OS) of 5 months. This study aims to evaluate the efficacy and safety of the anti-programmed death ligand-1 (PD-L1) antibody Avelumab in patients (pts) with NEN G3 progressing after first-line chemotherapy. Methods: In a multicenter, national, single-arm, open-label, phase II trial the efficacy and safety of Avelumab was evaluated in patients with metastatic progressive Neuroendocrine Carcinomas (NEC G3) according to WHO 2010, excluding Merkel cell carcino…