belzutifan + fulvestrant

This is a combination of **belzutifan** (a small molecule inhibitor of hypoxia-inducible factor-2 alpha, HIF-2α) and **fulvestrant** (a selective estrogen receptor degrader). Belzutifan reduces tumor progression by inhibiting HIF-2α, which is often upregulated in cancer through VHL pathway disruption, thereby lowering angiogenesis and cell survival signals. Fulvestrant antagonizes and degrades the estrogen receptor, blocking estrogen-driven cancer proliferation. The combination is under investigation for **estrogen receptor-positive, HER2-negative, unresectable or metastatic breast cancer** that has progressed following prior endocrine therapy[1][5][6][7].

Brand names

WELIREG + Faslodex

Other names

HIF-2α inhibitor + estrogen receptor antagonist