1352427-10-1Relevant articles and documents
Identification of an Orally Bioavailable Chromene-Based Selective Estrogen Receptor Degrader (SERD) That Demonstrates Robust Activity in a Model of Tamoxifen-Resistant Breast Cancer
Nagasawa, Johnny,Govek, Steven,Kahraman, Mehmet,Lai, Andiliy,Bonnefous, Celine,Douglas, Karensa,Sensintaffar, John,Lu, Nhin,Lee, Kyoungjin,Aparicio, Anna,Kaufman, Josh,Qian, Jing,Shao, Gang,Prudente, Rene,Joseph, James D.,Darimont, Beatrice,Brigham, Daniel,Maheu, Kate,Heyman, Richard,Rix, Peter J.,Hager, Jeffrey H.,Smith, Nicholas D.
, p. 7917 - 7928 (2018/09/06)
About 75% of breast cancers are estrogen receptor alpha (ER-α) positive, and women typically initially respond well to antihormonal therapies such as tamoxifen and aromatase inhibitors, but resistance often emerges. Fulvestrant is a steroid-based, selective estrogen receptor degrader (SERD) that both antagonizes and degrades ER-α and shows some activity in patients who have progressed on antihormonal agents. However, fulvestrant must be administered by intramuscular injections that limit its efficacy. We describe the optimization of ER-α degradation efficacy of a chromene series of ER modulators resulting in highly potent and efficacious SERDs such as 14n. When examined in a xenograft model of tamoxifen-resistant breast cancer, 14n (ER-α degradation efficacy = 91%) demonstrated robust activity, while, despite superior oral exposure, 15g (ER-α degradation efficacy = 82%) was essentially inactive. This result suggests that optimizing ER-α degradation efficacy in the MCF-7 cell line leads to compounds with robust effects in models of tamoxifen-resistant breast cancer derived from an MCF-7 background.