Severe Ocular Adverse Reaction Following Single Pembrolizumab Infusion: A Case Report

1.1. Purpose: To report a case of severe sight loss following single infusion of pembrolzumab 1.2. Methods: Retrospective case report 1.3. Results: Ocular adverse events associated with immune checkpoint inhibitors, due to their rarity, remain poorly characterised. Pembrolizumab targets the programmed cell death (PD-1) protein on T cells, circumventing the mechanisms by which cancer cells evade the body’s adaptive immune response. To date, reports of ocular surface disease, neuro-ophthalmic complications, orbitopathy, retinal dysfunction and uveitis have been reported following pembrolizumab infusion. We report the first case of severe panuveitis resulting in loss of vision, following a single initial infusion of pembrolizumab. 1.4. Conclusion: The case serves as a heartening reminder of the need for prompt reporting of visual symptoms, recognition of ocular immune-related adverse events and a multi-disciplinary approach between oncology and ophthalmology in patients receiving immunotherapy for cancer treatment.