I3Y-MC-JPEF: postMONARCH: A Randomized, Double Blind, Placebo-Controlled, Phase 3 Study to Compare the Efficacy of Abemaciclib Plus Fulvestrant to Placebo Plus Fulvestrant in Participants With HR+, HER2-, Advanced or Metastatic Breast Cancer Following Progression on a CDK4 & 6 Inhibitor and Endocrine Therapy

Status

Active, not recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2023-506771-10-00

Acronym

I3Y-MC-JPEF

Enrollment

154

Registered

2024-02-26

Start date

2022-03-11

Completion date

Unknown

Last updated

2026-01-19

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Neoplasm, Neoplasm Metastasis

Brief summary

Progression-Free Survival (PFS)

Interventions

DRUGVerzenios 50 mg film-coated tablets

DRUGPlacebo to match abemaciclib

DRUGFULVESTRANT

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Design outcomes

Primary

Measure	Time frame
Progression-Free Survival (PFS)	—

Countries

Belgium, Czechia, Denmark, France, Greece, Hungary, Italy, Poland, Spain

Outcome results

None listed

Source: EU CTIS · Data processed: Feb 4, 2026