PDCD1 and melanoma: The KEYNOTE-151 study (ClinicalTrials.gov identifier: NCT02821000) showed a 13.3% ORR with pembrolizumab in Chinese patients with mucosal melanoma refractory to chemotherapy.16 However, a phase II trial of toripalimab, also known as JS001 or TAB001, a humanized immunoglobulin G4 monoclonal antibody against PD-1,17 in 128 pretreated Chinese patients with advanced melanoma showed a higher ORR for patients with CSD (35.3%) and non-CSD (33.3%) subtypes than for patients with the mucosal subtype (0%).18