PDCD1 and melanoma: However, clinical advice to the ERG was that, in the NHS, many patients with advanced (unresectable or metastatic) BRAF V600 mutation-positive melanoma are treated with a programmed cell death protein 1 (PD-1) inhibitor immunotherapy as a first-line treatment and the rationale for not including immunotherapies as comparators in the final scope was unclear to the ERG.