NCT07410559

Neoadjuvant Imlunestrant Plus Abemaciclib Treatment Guided by Ki67 Index After 2 Weeks for ER-Positive HER2-Negative Breast Cancer

Neoadjuvant Imlunestrant Plus Abemaciclib Treatment Guided by Ki67 Index After 2 Weeks for ER-Positive HER2-Negative Breast Cancer: A Randomized Phase 2 Trial (IMPATIENS)

• Status: Not Yet Recruiting
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 189 (estimated)
• Sponsor: Fudan University · Academic / Other
• Sex: Female
• Age: 18 Years – 75 Years
• Healthy volunteers: Not accepted

Summary

This is a prospective, open-label, single-center, randomized controlled Phase II clinical study aimed at evaluating the efficacy and safety of neoadjuvant imlunestrant combined with abemaciclib guided by the Ki67 index after 2 weeks in patients with ER+/HER2- breast cancer.

Detailed description

This is a prospective, open-label, single-center, randomized controlled Phase II clinical study aimed at evaluating the efficacy and safety of neoadjuvant imlunestrant combined with abemaciclib guided by the Ki67 index after 2 weeks in patients with ER+/HER2- breast cancer. Eligible subjects who provide informed consent will first receive a 2-week window-of-opportunity treatment with imlunestrant combined with abemaciclib, followed by a biopsy of the primary lesion to assess Ki67 at 2 weeks. If the Ki67 of the primary lesion after 2 weeks is \<7.4%, they will be randomized in a 1:1 ratio to either Imlunestrant plus abemaciclib or neoadjuvant chemotherapy. If the Ki67 of the primary lesion after 2 weeks is ≥7.4%, patients will be assigned to neoadjuvant chemotherapy.

Conditions

• Breast Cancer

Interventions

Type	Name	Description
DRUG	Imlunestrant + abemaciclib	Imlunestrant (400 mg orally, once daily) combined with abemaciclib (150 mg orally, twice daily) for 24 weeks.
DRUG	(dd)EC*4-T*4	Epirubicin (90 mg/m², intravenous infusion) combined with cyclophosphamide (600 mg/m², intravenous infusion, every 2 weeks or 3 weeks, determined by investigators) for 4 cycles, followed by docetaxel (100 mg/m², intravenous infusion, every 3 weeks) for 4 cycles.

Timeline

• Start date: 2026-07-01
• Primary completion: 2029-04-01
• Completion: 2031-07-01
• First posted: 2026-02-13
• Last updated: 2026-02-18

Locations

1 site across 1 country: China