PMEL and Fever: The dominant toxicities, mirroring the drug’s mechanism, were skin events from gp100-positive melanocyte targeting (rash 87% any-grade, 16% grade ≥ 3; pruritus 67%, 4% grade ≥ 3) and cytokine-mediated effects from T-cell activation (pyrexia 80%, chills 64%, nausea 59%).