PDCD1 and juvenile idiopathic arthritis: Here, we report a case in which pembrolizumab (anti-PD-1 antibody) was co-administered with tocilizumab, an anti-IL-6 receptor antibody that is FDA-approved for the treatment of rheumatoid arthritis, juvenile idiopathic arthritis, and polyarticular juvenile rheumatoid arthritis, in a patient with concomitant advanced melanoma and refractory Crohn’s disease.