Palazestrant

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.

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].

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

References:
[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.