endoxifen + abemaciclib

This is a combination therapy of (Z)-endoxifen, a potent selective estrogen receptor modulator (SERM), and abemaciclib, a cyclin-dependent kinase 4/6 inhibitor. The combination is being investigated as a neoadjuvant treatment for women with newly diagnosed estrogen receptor positive (ER+), human epidermal growth factor receptor 2 negative (HER2-) breast cancer. (Z)-Endoxifen acts by inhibiting and degrading the estrogen receptor and also targets protein kinase C beta 1 (PKCβ1), an oncogenic protein associated with cancer cell proliferation. Abemaciclib inhibits CDK4/6 proteins, which are critical regulators of cell cycle progression in cancer cells. The rationale for combining these agents is to enhance antitumor efficacy by simultaneously blocking estrogen-driven signaling and cell cycle progression pathways[2][4][5][6][7]. The combination has shown promising early results in clinical trials, including significant reductions in tumor proliferation markers such as Ki-67 and tumor size over 24 weeks of pre-surgical treatment[5][6]. Atossa Therapeutics is developing the proprietary oral formulation of (Z)-endoxifen that does not require liver metabolism.

Other names

(Z)-endoxifen + abemaciclib(Z)-endoxifen plus VERZENIO