EPAS1 and renal carcinoma: In 2025, Casdatifan (AB521) became the newest small molecule variant inhibitor of HIF‐2α, which, like YQ‐0629, also binds to the PAS‐B structural domain of HIF‐2α, inhibits HIF‐2α and HIF‐2α downstream target genes, VEGF and EPO, in HepG2, renal carcinoma cells, endothelial cells, and M2‐type macrophages, and was inactive against HIF‐1α [92].