SYK Inhibitor Entospletinib Prevents Ocular and Skin GVHD in Mice

The study demonstrated that the SYK inhibitor entospletinib (ENTO) effectively prevented ocular and skin graft-versus-host disease (GVHD) in mice following hematopoietic cell transplantation. ENTO treatment improved survival rates, with 60% of treated mice surviving to day +120 compared to 10% in the placebo group. It significantly ameliorated symptoms such as alopecia and skin pathology by reducing SYK+ cells and improving immune cell reconstitution, including increased frequencies of monocytes, B cells, and T cells. ENTO also selectively targeted pathogenic B cells without affecting T cells or monocytes, suggesting its potential as a prophylactic treatment for GVHD. The study involved 9-10 mice per group and was supported by the National Institutes of Health and Gilead Sciences.