Cytokines in PD-1 immune checkpoint inhibitor adverse events and implications for the treatment of uveitis

Immune checkpoint inhibitors (ICI) such as Programmed cell Death 1 (PD-1) inhibitors have improved cancer treatment by enhancing the immune system’s ability to target malignant cells. Their use is associated with immune-related adverse events (irAEs), including uveitis. The profile of pro-inflammatory cytokines underlying Anti-PD-1-induced uveitis shares significant overlap with that of non-infectious uveitis. Current corticosteroid treatments for uveitis while effective are fraught with vision threatening side effects. The cytokine profile in ICI-related uveitis has a large overlap with that of noninfectious uveitis, this overlap strongly supports the potential for therapy that activates the PD-1 axis in the eye to treat uveitis. Indeed, ICI related uveitis often resolves with cessation of the ICI, restoring the endogenous PD-1 axis. The potential benefit of targeting many pro-inflammatory cytokines via local PD-1 axis activation is mitigating ocular inflammation while minimizing adverse effects.