PT2399 is primarily used in research settings to study the hypoxia-inducible factor (HIF) pathway, which plays a critical role in cellular responses to low oxygen levels. It acts as a selective inhibitor of HIF-2α, making it a valuable tool for investigating the role of HIF-2α in various diseases, particularly cancer. By inhibiting HIF-2α, PT2399 helps researchers understand its contribution to tumor growth, angiogenesis, and metastasis in cancers such as renal cell carcinoma. Additionally, it is used to explore potential therapeutic strategies targeting hypoxia-related pathways in other conditions, including cardiovascular diseases and inflammatory disorders. Its application extends to preclinical studies aimed at developing novel treatments for diseases driven by hypoxia signaling.