Dr. Goetz on the Clinical Significance of Lasofoxifene in ER+/HER2- Breast Cancer

Matthew P. Goetz, MD, consultant, Division of Medical Oncology, Department of Oncology, Mayo Clinic, discusses the clinical significance of the phase 2 ELAINE-1 trial (NCT03781063) of lasofoxifene in patients with ESR1-mutated, estrogen receptor (ER)–positive/HER2-negative metastatic breast cancer.

ELAINE-1 evaluated the safety and efficacy of lasofoxifene vs fulvestrant (Faslodex) in this patient population. Lasofoxifene demonstrated clear evidence of antitumor activity as monotherapy in ELAINE-1, Goetz says. Additionally, the combination of lasofoxifene and abemaciclib (Verzenios) demonstrated activity in patients with ESR1-mutated, ER-positive/HER2-negative advanced breast cancer who progressed on a CDK4/6 inhibitor during the phase 2 ELAINE-2 trial (NCT04432454), Goetz explains.

Additional trials evaluating lasofoxifene and other selective estrogen receptor modulators will be critical for the further development of these agents, Goetz continues. The overarching goal is to develop improved therapies to treat patients with ESR1 mutations and potentially prevent them, Goetz concludes.