Skip to content
Triangle logo TriangleGet started
← Full study record

NCT04975308 · OUTCOME

Investigator-assessed PFS (Between Arm C and Arm A)

A Study of Imlunestrant, Investigator's Choice of Endocrine Therapy, and Imlunestrant Plus Abemaciclib in Participants With ER+, HER2- Advanced Breast Cancer · Source last updated 2026-07-22

Results reported by the registry submitting party. Population, time horizon, units and missing values must be read together.

Measure
MEDIAN
Unit
Months
Interval / dispersion
95% Confidence Interval
Time frame
Randomization to the date of first documented progression of disease or death from any cause (up to 26 months)

What was measured

PFS was defined as the time from randomization to the date of first documented progression of disease or death from any cause in the absence of disease progression using Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 criteria, as assessed by investigator. Progressive disease (PD) was defined as at least a 20% increase in the sum of the diameters of target lesions, with reference being the smallest sum on study and an absolute increase of at least 5 mm, or unequivocal progression of non-target lesions, or 1 or more new lesions. Participants known to be alive and without disease progression were censored at the date of their last adequate tumor assessment per RECIST 1.1 criteria, or date of randomization (whichever is later).

Analysis population: All participants who were randomly assigned to either arm A or arm C concurrently (including censored). Number of participants censored in "Arm C=99," "Arm A=64."

Groups in this outcome

Arm C: Imlunestrant + Abemaciclib

Participants received Imlunestrant 400 mg orally once daily on Days 1 to 28 of a 28-day cycle, plus Abemaciclib 150 mg orally twice daily on Days 1 to 28 of a 28-day cycle, until disease progression or a criterion for discontinuation was met.

Arm A: Imlunestrant

Participants received Imlunestrant 400 milligrams (mg) orally once daily on days 1 to 28 of a 28-day cycle, until disease progression or a criterion for discontinuation were met.

Group identifiers and denominators belong to this outcome only. They may differ in another outcome or in safety reporting.

Analysis denominator · Participants

GroupSource count
Arm C: Imlunestrant + Abemaciclib213
Arm A: Imlunestrant213

Reported measurements

Source class 1
Values in Months · Interval/dispersion: 95% Confidence Interval
GroupValueSpreadLowerUpperComment
Arm C: Imlunestrant + Abemaciclib9.36Not reported7.4911.86Not reported
Arm A: Imlunestrant5.49Not reported3.785.62Not reported

Source statistical analyses

Group order, estimate direction, methods and comments are retained. No treatment ranking is inferred.

  1. ci Lower Limit
    0.441
    ci Num Sides
    TWO_SIDED
    ci Pct Value
    95
    ci Upper Limit
    0.733
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    <0.0001
    param Type
    Hazard Ratio (HR)
    param Value
    0.569
    statistical Method
    Log Rank
Complete source fields
analyses
  1. ci Lower Limit
    0.441
    ci Num Sides
    TWO_SIDED
    ci Pct Value
    95
    ci Upper Limit
    0.733
    group Ids
    1. OG000
    2. OG001
    non Inferiority Type
    SUPERIORITY
    p Value
    <0.0001
    param Type
    Hazard Ratio (HR)
    param Value
    0.569
    statistical Method
    Log Rank
classes
  1. categories
    1. measurements
      1. group Id
        OG000
        lower Limit
        7.49
        upper Limit
        11.86
        value
        9.36
      2. group Id
        OG001
        lower Limit
        3.78
        upper Limit
        5.62
        value
        5.49
denoms
  1. counts
    1. group Id
      OG000
      value
      213
    2. group Id
      OG001
      value
      213
    units
    Participants
description
PFS was defined as the time from randomization to the date of first documented progression of disease or death from any cause in the absence of disease progression using Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 criteria, as assessed by investigator. Progressive disease (PD) was defined as at least a 20% increase in the sum of the diameters of target lesions, with reference being the smallest sum on study and an absolute increase of at least 5 mm, or unequivocal progression of non-target lesions, or 1 or more new lesions. Participants known to be alive and without disease progression were censored at the date of their last adequate tumor assessment per RECIST 1.1 criteria, or date of randomization (whichever is later).
dispersion Type
95% Confidence Interval
groups
  1. description
    Participants received Imlunestrant 400 mg orally once daily on Days 1 to 28 of a 28-day cycle, plus Abemaciclib 150 mg orally twice daily on Days 1 to 28 of a 28-day cycle, until disease progression or a criterion for discontinuation was met.
    id
    OG000
    title
    Arm C: Imlunestrant + Abemaciclib
  2. description
    Participants received Imlunestrant 400 milligrams (mg) orally once daily on days 1 to 28 of a 28-day cycle, until disease progression or a criterion for discontinuation were met.
    id
    OG001
    title
    Arm A: Imlunestrant
param Type
MEDIAN
population Description
All participants who were randomly assigned to either arm A or arm C concurrently (including censored). Number of participants censored in "Arm C=99," "Arm A=64."
reporting Status
POSTED
time Frame
Randomization to the date of first documented progression of disease or death from any cause (up to 26 months)
title
Investigator-assessed PFS (Between Arm C and Arm A)
type
PRIMARY
unit Of Measure
Months

Download exact source JSON → · Snapshot ctgov-results-191f4516d4760045304b24a0

Preserved source evidence · Not medical advice