HLA-DRB1*04:05 is involved in the development of Vogt–Koyanagi–Harada disease-like immune-related adverse events in patients receiving immune checkpoint inhibitors

Immune checkpoint inhibitors (ICIs) activate anti-tumor activity by inhibiting immune checkpoint molecules that suppress inflammatory T-cell activity. However, ICIs can initiate excessive immune responses, thereby causing immune-related adverse events (irAEs). ICI-associated uveitis (ICIU) is an irAE that affects the eyes. Although Vogt–Koyanagi–Harada disease (VKH)-like uveitis is a common form of ICIU, it is unclear which factors determine the ICIU form. We retrospectively reviewed the medical records of nine ICIU cases treated with ICIs for malignancies. We also performed HLA typing in seven cases to investigate the association between HLA and disease type. Fisher's exact test was used for the statistical analysis. Five of the ICIU cases were VKH-like ICIUs, and four were non-VKH-like ICIUs. No association was found between mean age, sex, primary disease, ICI, time to onset, and disease type. Four patients with VKH-like uveitis underwent HLA genotyping and were all positive for HLA-DRB1*04:05. All 3 patients with non-VKH-like uveitis were negative for HLA-DRB1*04:05. Statistical analysis showed that HLA-DRB1*04:05 was significantly associated with developing VKH-like ICIU (P = 0.029). In ICIU, HLA-DRB1*04:05 was associated with the pathogenesis of VKH-like uveitis, suggesting that ICI-associated VKH-like uveitis has a similar pathogenesis to VKH.