giredestrant + inavolisib + palbociclib

**giredestrant + inavolisib + palbociclib** is an investigational oral combination regimen targeting advanced hormone receptor-positive, HER2-negative breast cancer, particularly in cases with PIK3CA mutations. - **Giredestrant** is a small molecule *selective estrogen receptor downregulator* (SERD) that blocks and degrades the estrogen receptor, inhibiting estrogen-driven tumor growth[2][4][5][6]. - **Inavolisib** is a *PI3Kα inhibitor* that selectively inhibits the phosphoinositide 3-kinase alpha (PI3Kα) isoform, aiming to block PI3K signaling dysregulated by PIK3CA mutations commonly found in breast cancer[1][3][7]. - **Palbociclib** is a *CDK4/6 inhibitor* that blocks cyclin-dependent kinases 4 and 6, thereby inhibiting cell cycle progression and proliferation of cancer cells[1][3][4][5][9]. This triple combination aims to synergistically suppress tumor proliferation by simultaneously disrupting estrogen receptor signaling, PI3K-driven mitogenic signaling, and cell cycle progression. It is being investigated mainly for patients with endocrine-resistant or advanced HR+/HER2- breast cancer, especially those with PIK3CA mutations.

Other names

selective estrogen receptor downregulator combination + PI3K inhibitor combination + CDK4/6 inhibitor combination