A Randomized, Controlled, Multi-center, Phase III Clinical Study to Investigate Recombinant Humanized PD-1 Monoclonal Antibody Injection (JS001) Versus Dacarbazine as the 1st-line Therapy for Unresectable or Metastatic Melanoma

This is one phase III, randomized, open-label study in comparison of JS001 with dacarbazine as the 1st-line therapy for adult (≥18 years) subjects with unresectable or metastatic melanoma. The subjects will be 1:1 randomized and stratified in accordance with acral lentiginous melanoma and M stage (M0vsM1a/M1bvsM1c). Using standard dose and dose interval, the subjects will be given JS001 240mg intravenously, once every two weeks, or dacarbazine 1000mg/m2, d1, intravenously, once every three weeks. One cycle of therapy is 6 weeks (3 doses of JS001 or 2 doses of dacarbazine per cycle).