Elacestrant (Orserdu)

Mechanism of action

From the NCI Drug Dictionary: An orally available, selective estrogen receptor degrader (SERD) and selective estrogen receptor modulator (SERM), with potential antineoplastic and estrogen-like activities. Upon oral administration of higher doses of elacestrant, this agent acts as a SERD, which binds to the estrogen receptor (ER) and induces a conformational change that results in the degradation of the receptor. This may inhibit the growth and survival of ER-expressing cancer cells. At lower doses of this agent, RAD1901 acts as a SERM and has estrogen-like effects in certain tissues, which can both reduce hot flashes and protect against bone loss. In addition, elacestrant is able to cross the blood-brain barrier (BBB).

Diseases for which it is established

• Breast cancer, ER-positive

History of changes in FDA indication

• 2023-01-27: Approved for postmenopausal women or adult men with ER-positive, HER2-negative, ESR1-mutated advanced or metastatic breast cancer with disease progression following at least one line of endocrine therapy. (Based on EMERALD)

History of changes in EMA indication

• 2023-09-20: Initial marketing authorization as Orserdu. Orserdu monotherapy is indicated for the treatment of postmenopausal women, and men, with estrogen receptor (ER)‑positive, HER2-negative, locally advanced or metastatic breast cancer with an activating ESR1 mutation who have disease progression following at least one line of endocrine therapy including a CDK 4/6 inhibitor.

Also known as

• Code name: RAD-1901
• Brand name: Orserdu