EMBER-4: a Phase 3 adjuvant trial of imlunestrant vs standard endocrine therapy in patients with ER+, HER2− early breast cancer with an increased risk of recurrence who have previously received 2 to 5 years of adjuvant ET

Objective Imlunestrant is an orally bioavailable selective estrogen receptor degrader (SERD) with pure antagonistic properties and the potential to overcome endocrine therapy (ET) resistance. In early phase trials, imlunestrant monotherapy showed favorable safety with pharmacokinetic (PK) exposures exceeding fulvestrant and preliminary efficacy in ER+, HER2− advanced breast cancer patients (EMBER) and robust biological/pharmacodynamic activity and tolerability in EBC (EMBER-2).