Efficacy, Safety, and Biomarkers of Toripalimab in Patients with Recurrent or Metastatic Neuroendocrine Neoplasms: A Multiple-Center Phase Ib Trial

Purpose: Patients with recurrent or metastatic neuroendocrine neoplasms (NEN) had a poor prognosis and few treatment options. Toripalimab, a humanized IgG4 antibody specific for human PD-1 receptor, was first approved to treat second-line metastatic melanoma in China in 2018. Patients and Methods: The multiple-center phase Ib trial enrolled patients with NENs (Ki-67 ≥ 10%) after failure of first-line therapy received 3 mg/kg toripalimab once...