Apristor®

A First-in-Class Progesterone Receptor Antagonist

ABOUT HORMONE DRIVEN CANCERS

Over 100,000 patients with metastatic breast, ovarian, prostate, or uterine cancers die per year in the United States. For many of these patients, continuous progesterone and estrogen signaling drives disease progression. Currently, only medicines that block estrogen are approved, meaning that progesterone signaling continues in those patients receiving anti-estrogen therapy.

ABOUT APRISTOR

Apristor (onapristone xr) is an investigational medicine that prevents progesterone signaling by blocking the interaction between progesterone and its binding partner, progesterone receptor. Apristor is the only known full PR antagonist. 

ROLE OF PR IN CANCER

Under normal conditions, progesterone is primarily responsible for the development of sex organs and for regulating the menstrual cycle. Cancer cells hijack progesterone to stimulate cancer cell proliferation, metastases, regeneration, and immune evasion.