The risk of ocular adverse events after anti-PD-1/PD-L1 antibodies is dose-independent: a prospective observation report

Background: Immune checkpoint inhibitors (ICIs) cause ICI-related adverse events (irAEs) such as dry eye and uveitis, sometimes necessitating the suspension of ICI treatment. To the best of my knowledge, this is the first prospective study on ocular irAEs. In this study, we aimed to identify early changes in ocular irAE and control conditions without suspending ICI treatment. Methods 22 participants who began ICI treatment between July 2020 and July 2021 in Keiyu Hospital, Japan (3 women and 19 men; age, 69.1 ± 7.9 years, range, 53–83 years) were prospectively evaluated. The patients underwent ocular examinations before and 1, 3, and every 2 months after the initial dose of ICI. Examinations included measurement of aqueous flare and central choroidal thickness (CCT). Results Among the 22 participants, 6 developed systemic irAEs. Of these 6 patients, one experienced ocular pain after ICI treatment, likely due to dry eye disease. We did not observe any change in CCT or aqueous flare, even in patients with systemic AEs. This result suggests that ocular irAE is dose- independent, and we cannot predict whether the patient have risks of presenting irAE by following up ocular findings. Conclusions Ocular irAEs occur dose-independently.