Belzutifan Attenuates Choroidal Neovascularization by Suppressing the HIF-2α/PAI-1 Axis.

Choroidal neovascularization (CNV) is the hallmark pathology of exudative age-related macular degeneration (AMD). Although anti-vascular endothelial growth factor (VEGF) therapy is widely used, its limitations, including drug resistance and treatment burden, necessitate alternative targets. This study aimed to investigate the role of hypoxia-inducible factor-2α (HIF-2α) in CNV pathogenesis and evaluate the therapeutic potential of its inhibitor Belzutifan, with a particular focus on validating the functional significance of the HIF-2α/plasminogen activator inhibitor-1 (PAI-1) axis. The efficacies of Belzutifan were assessed in a laser-induced CNV rat model using H&E staining, OCT, fundus photography, and immunofluorescence. Network pharmacology identified potential therapeutic pathways. In vitro, CoCl₂-injured HUVECs were used to evaluate the effects of drugs on proliferation, migration, and tube formation. The expression levels of HIF-2α, PAI-1, VEGF-A, Ve-cadherin, and inflammatory factors were assessed by ELISA, immunofluorescence, and Western blot analysis. This study demonstrated that Belzutifan inhibits CNV by targeting the HIF-2α/PAI-1 axis. It also showed that Belzutifan can markedly reduce the expression levels of pro-inflammatory cytokines (IL-6, IL-1β, and TNF-α). Both the HIF-2α inhibitor and the PAI-1 inhibitor suppressed the proliferation, migration, and tube formation of HUVECs. Intravitreal injection of both inhibitors effectively reduced neovascularization from Day 14 to Day 21 in the laser-induced CNV rat model. Collectively, these findings provide a novel therapeutic strategy for exudative AMD and highlight its significant clinical translational value.