NCT07159451

A Short-term Preoperative, Evaluating Activity and Safety of Elacestrant Monotherapy as Compared to Elacestrant + Ovarian Function Suppression (LHRH Agonist) in Premenopausal Patients With Stage I-II ER+/HER2- Breast Cancer

A Short-term Preoperative, Window-of-opportunity Study, Evaluating Activity and Safety of Elacestrant Monotherapy as Compared to Elacestrant + Ovarian Function Suppression (LHRH Agonist) in Premenopausal Patients With Stage I-II ER+/HER2- Breast Cancer

• Status: Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 140 (estimated)
• Sponsor: Gustave Roussy, Cancer Campus, Grand Paris · Academic / Other
• Sex: Female
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

A prospective randomized trial designed to evaluate the mean decrease in Ki67 after 4 weeks of elacestrant monotherapy and in combination with leuprorelin in patients with early-stage HR+ BC. This preoperative study will enroll consecutive patients with early stage HR+ BC who are not candidates for neoadjuvant chemotherapy but are eligible for short-term preoperative treatment with elacestrant, with or without leuprorelin, followed by breast surgery. A total of three dedicated Formalin-fixed paraffin embedded (FFPE) samples (mandatory for all patients), along with two frozen biopsy (only for participants at Gustave Roussy), are planned to be collected at the time of inclusion from the biopsy sample and from the surgical specimen. Blood samples will also be collected throughout the study.

Conditions

• Breast Cancer

Interventions

Type	Name	Description
DRUG	Elacestrant	Patients will receive elacestrant 345 mg/daily administered orally for 4 weeks.
DRUG	Leuprorelin	Patients randomized in arm B will recieve Leuprorelin at Day 1 and Day 29

Timeline

• Start date: 2025-10-06
• Primary completion: 2027-01-29
• Completion: 2027-05-29
• First posted: 2025-09-08
• Last updated: 2025-12-01

Locations

1 site across 1 country: France