ELAINE 3: phase 3 study of lasofoxifene plus abemaciclib to treat ER+/HER2-, ESR1-mutated, metastatic breast cancer.

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All Authors

Goetz, MP.
Wander, SA.
Bachelot, T.
de Nonneville, A.
Gal-Yam, EN.
Sammons, SL.
Shen, S.
Twelves, C.
Boruta, G.
Portman, DJ.

LTHT Author

Twelves, Chris

LTHT Department

Oncology

Non Medic

Publication Date

2025

Item Type

Journal Article
Clinical Trial

Language

Subject

Subject Headings

Abstract

Endocrine therapy (ET) is recommended for patients with estrogen receptor-positive (ER+) metastatic breast cancer (mBC), but most patients will develop treatment resistance, often due to mutations in the ER-alpha-coding gene, ESR1. Therapeutic options are limited for endocrine-resistant mBC, particularly following treatment with a cyclin-dependent kinase 4/6 inhibitor (CDK4/6i). Lasofoxifene had anti-tumor activity in two separate phase 2, open-label studies (ELAINE 1 and 2) when given as monotherapy or combined with abemaciclib. The phase 3, randomized ELAINE 3 trial will evaluate the efficacy and safety of lasofoxifene/abemaciclib versus fulvestrant/abemaciclib for locally advanced or metastatic, ER+/HER2- breast cancer with an ESR1 mutation that progressed after ET-CDK4/6i treatment. Enrollment is planned for up to 500 patients to evaluate progression-free survival as the primary endpoint. Clinical trial registration: www.clinicaltrials.gov identifier is NCT05696626.

Journal

Future Oncology