Palazestrant  (Synonyms: OP-1250)

Palazestrant is an antiestrogen and antineoplastic agent. Palazestrant can completely inhibit the activity of 17b-estradiol (E2) with IC₅₀ value of 6.4 nM, and inhibit the proliferation of MCF7 and CAMA-1 cells with IC₅₀ value of 1.4-1.6 nM. Palazestrant can inhibit ER⁺/HER2⁺ cancer^[1][2][3].

Palazestrant (0-300 nM, 24 h) can completely inhibit the activity of 17b-estradiol (E2) with IC₅₀ value of 6.4 nM, and inhibit the proliferation of MCF7 and CAMA-1 cells with IC₅₀ value of 1.4-1.6 nM^[3].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

Palazestrant (0-100 mg/kg/day for 3 days. p.o.) alone or in combination with Palbociclib (HY-50767), Ribociclib (HY-15777) or Alpelisib (HY-15244) can effectively inhibit the proliferation and brain metastasis of ER-positive breast cancer^[3].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

449.60

C₂₈H₃₆FN₃O

2092925-89-6

Solid

White to off-white

CC(C)(F)CN1[C@H](C2=CC=C(C=C2)OC3CN(C3)CCC)C4=C(C[C@H]1C)C5=CC=CC=C5N4

Room temperature in continental US; may vary elsewhere.

• [1]. Harmon CL, et al. Methods of treating estrogen receptor-associated diseases such as ER+/HER2+ cancer using an estrogen receptor antagonist: World Intellectual Property Organization, WO2023283329. 2023-01-12.

  [2]. WHO Drug Information-World Health Organization (WHO).

  [3]. Parisian AD, et al. Palazestrant (OP-1250), A Complete Estrogen Receptor Antagonist, Inhibits Wild-type and Mutant ER-positive Breast Cancer Models as Monotherapy and in Combination. Mol Cancer Ther. 2024 Mar 4;23(3):285-300.  [Content Brief]