PDCD1 and melanoma: While the previously discussed studies report limited anti-tumour activity in advanced solid tumour or CRC cohorts, a study (RELATIVITY-047) evaluating relatlimab (IgG4 LAG-3-blocking antibody) in untreated advanced melanoma reported a significantly longer progression-free survival of 10.1 months when combined with anti-PD-1 nivolumab compared with 4.6 months for nivolumab alone [33].