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← Femara: Breast cancer with HR positive

NCT05104866 · STUDY IN CONTEXT

A Phase-3, Open-Label, Randomized Study of Dato-DXd Versus Investigator's Choice of Chemotherapy (ICC) in Participants With Inoperable or Metastatic HR-Positive, HER2-Negative Brea

Draft scope assessment: unclear. Attached because the study's own record names HR. The study was not selected for this indication by its sponsor, and its eligibility has not been reconciled against this page in full. Found because this study's registry identifier is printed in an FDA approval notice, an FDA product label or an NCI summary held by this site. The citing document and the exact position of the identifier inside it are recorded. Being cited is not a statement that the study supports this treatment.

Read the full study record and all posted results →

Linked outcomes

Measures are not ranked. Open each original source section for treatment groups, denominators, units and results.

primary · POSTED

PFS is defined as time from randomization until progression per RECIST 1.1, as assessed by BICR, or death due to any cause. The analysis will include all randomized participants as randomized regardless of whether the participant withdraws from therapy, receives another anti-cancer therapy, or clinically progresses prior to RECIST 1.1.

Source null

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primary · POSTED

OS is defined as time from randomization until the date of death due to any cause. The comparison will include all randomized participants as randomized, regardless of whether the participant withdraws from therapy or receives another anti-cancer therapy. The measure of interest is the hazard ratio of OS.

Source null

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secondary · POSTED

Objective response rate is defined as the proportion of participants who have a confirmed CR or PR, as determined by the BICR/Investigator assessment, per RECIST 1.1.

Source null

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secondary · POSTED

Duration of response is defined as the time from the date of first documented confirmed response until date of documented progression per RECIST 1.1, as assessed by BICR assessment or death due to any cause.

Source null

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secondary · POSTED

Duration of response is defined as the time from the date of first documented confirmed response until date of documented progression per RECIST 1.1, as assessed by Investigator assessment or death due to any cause.

Source null

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secondary · POSTED

PFS by Investigator assessment will be defined as the time from the date of randomization until the date of PD per RECIST 1.1 (by Investigator assessment) or death (by any cause in the absence of progression), (ie, date of event or censoring - date of randomization + 1).

Source null

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Reported safety

Serious events are not the same as severe events. Compare the original safety groups and their at-risk populations.

Open the study safety table →

Quality of life and patient-reported measures

EORTC QLQ · Clinical Outcome Assessment- TTD in Pain

Score direction: Not stated by the study. Direction is never inferred from an instrument name.

release id
clinical-indications-draft-1
disease state id
ds-breast-cancer-femara-ea5f0363
nct id
NCT05104866
qol key
qol-0010
source section id
NCT05104866-om-0010
source outcome index
10
instrument
EORTC QLQ
instrument basis
matched 'eortc' in the study's own wording
scale title
Clinical Outcome Assessment- TTD in Pain
measure definition
Time to deterioration in pain as measured by the pain scale from EORTC QLQ-C30. Deterioration is defined as a 16.6 increase in score relative to baseline score
time frame
From date of randomization to 18 weeks post-progression. Assessments occur every 3 weeks then every 6 weeks until 18 weeks post-progression and at end of treatment visit. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
analysis role
secondary
reporting status
POSTED
higher is better
Source null
direction quote
Source null
population note
Source null
curation status
draft
reviewed by
Source null
reviewed at
Source null
created at
2026-09-10T00:00:00Z
Open the exact result →
EORTC QLQ · Clinical Outcome Assessment- TTD in Physical Functioning

Score direction: Not stated by the study. Direction is never inferred from an instrument name.

release id
clinical-indications-draft-1
disease state id
ds-breast-cancer-femara-ea5f0363
nct id
NCT05104866
qol key
qol-0011
source section id
NCT05104866-om-0011
source outcome index
11
instrument
EORTC QLQ
instrument basis
matched 'eortc' in the study's own wording
scale title
Clinical Outcome Assessment- TTD in Physical Functioning
measure definition
Time to deterioration in physical functioning as measured by the physical functioning scale from EORTC QLQ-C30. Deterioration is defined as a 13.3 decrease in score relative to baseline score.
time frame
From date of randomization to 18 weeks post-progression. Assessments occur every 3 weeks then every 6 weeks until 18 weeks post-progression and at end of treatment visit. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
analysis role
secondary
reporting status
POSTED
higher is better
Source null
direction quote
Source null
population note
Source null
curation status
draft
reviewed by
Source null
reviewed at
Source null
created at
2026-09-10T00:00:00Z
Open the exact result →
EORTC QLQ · Clinical Outcome Assessment- TTD in GHS

Score direction: Not stated by the study. Direction is never inferred from an instrument name.

release id
clinical-indications-draft-1
disease state id
ds-breast-cancer-femara-ea5f0363
nct id
NCT05104866
qol key
qol-0012
source section id
NCT05104866-om-0012
source outcome index
12
instrument
EORTC QLQ
instrument basis
matched 'eortc' in the study's own wording
scale title
Clinical Outcome Assessment- TTD in GHS
measure definition
Time to deterioration in global health status/QoL as measured by the global health status/QoL scale from EORTC QLQ-C30. Deterioration is defined as a 16.6 decrease in score relative to baseline score.
time frame
From date of randomization to 18 weeks post-progression. Assessments occur every 3 weeks then every 6 weeks until 18 weeks post-progression and at end of treatment visit. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
analysis role
secondary
reporting status
POSTED
higher is better
Source null
direction quote
Source null
population note
Source null
curation status
draft
reviewed by
Source null
reviewed at
Source null
created at
2026-09-10T00:00:00Z
Open the exact result →
Full draft applicability and source-link record
trial
release id
clinical-indications-draft-1
disease state id
ds-breast-cancer-femara-ea5f0363
nct id
NCT05104866
trial label
A Phase-3, Open-Label, Randomized Study of Dato-DXd Versus Investigator's Choice of Chemotherapy (ICC) in Participants With Inoperable or Metastatic HR-Positive, HER2-Negative Brea
applicability
unclear
applicability note
Attached because the study's own record names HR. The study was not selected for this indication by its sponsor, and its eligibility has not been reconciled against this page in full.
curation status
draft
reviewed by
Source null
reviewed at
Source null
created at
2026-09-10T00:00:00Z
provenance class
regulator-cited
discovery note
Found because this study's registry identifier is printed in an FDA approval notice, an FDA product label or an NCI summary held by this site. The citing document and the exact position of the identifier inside it are recorded. Being cited is not a statement that the study supports this treatment.
outcome Count
6
harms Count
2
qol Count
3
outcomes
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0000
    source section id
    NCT05104866-om-0000
    source outcome index
    0
    endpoint
    Progression-Free Survival
    endpoint definition
    PFS is defined as time from randomization until progression per RECIST 1.1, as assessed by BICR, or death due to any cause. The analysis will include all randomized participants as randomized regardless of whether the participant withdraws from therapy, receives another anti-cancer therapy, or clinically progresses prior to RECIST 1.1.
    time origin
    On-study tumor assessments occur every 6 weeks then every 9 weeks until disease progression, death or withdrawal of consent assessed up to data cut-off (17Jul2023) to a maximum of approximately 21 months
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0001
    source section id
    NCT05104866-om-0001
    source outcome index
    1
    endpoint
    Overall Survival
    endpoint definition
    OS is defined as time from randomization until the date of death due to any cause. The comparison will include all randomized participants as randomized, regardless of whether the participant withdraws from therapy or receives another anti-cancer therapy. The measure of interest is the hazard ratio of OS.
    time origin
    From date of randomization until death due to any cause. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
    analysis role
    primary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  3. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0002
    source section id
    NCT05104866-om-0002
    source outcome index
    2
    endpoint
    Objective Response Rate (ORR)
    endpoint definition
    Objective response rate is defined as the proportion of participants who have a confirmed CR or PR, as determined by the BICR/Investigator assessment, per RECIST 1.1.
    time origin
    From date of randomization until event. Assessed up to data cut-off (17Jul2023) to a maximum of approximately 21 months for BICR assessment and assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months for investigator assessment.
    analysis role
    secondary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  4. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0003
    source section id
    NCT05104866-om-0003
    source outcome index
    3
    endpoint
    Duration of Response (DoR) as Assessed by BICR Assessment
    endpoint definition
    Duration of response is defined as the time from the date of first documented confirmed response until date of documented progression per RECIST 1.1, as assessed by BICR assessment or death due to any cause.
    time origin
    From date of first response until progression or death. Tumor assessments occur every 6 weeks then every 9 weeks until disease progression, death or withdrawal of consent. Assessed up to data cut-off (17Jul2023) to a maximum of approximately 21 months.
    analysis role
    secondary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  5. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0004
    source section id
    NCT05104866-om-0004
    source outcome index
    4
    endpoint
    Duration of Response (DoR) as Assessed by Investigator Assessment
    endpoint definition
    Duration of response is defined as the time from the date of first documented confirmed response until date of documented progression per RECIST 1.1, as assessed by Investigator assessment or death due to any cause.
    time origin
    From date of first response until progression or death. Tumor assessments occur every 6 weeks then every 9 weeks until disease progression, death or withdrawal of consent. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months
    analysis role
    secondary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  6. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0005
    source section id
    NCT05104866-om-0005
    source outcome index
    5
    endpoint
    Progression-Free Survival by Investigator Assessment
    endpoint definition
    PFS by Investigator assessment will be defined as the time from the date of randomization until the date of PD per RECIST 1.1 (by Investigator assessment) or death (by any cause in the absence of progression), (ie, date of event or censoring - date of randomization + 1).
    time origin
    On-study tumor assessments occur every 6 weeks then every 9 weeks until disease progression, death or withdrawal of consent assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months
    analysis role
    secondary
    reporting status
    POSTED
    data cutoff
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
arms
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0000
    arm key
    OG000
    arm label
    Dato-DXd
    regimen
    Arm 1: Dato-DXd
    analyzed count
    365
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0000#groups/OG000
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0000
    arm key
    OG001
    arm label
    Investigator's Choice of Chemotherapy (ICC)
    regimen
    Arm 2: ICC (Capecitabine or Gemcitabine or Eribulin mesylate or Vinorelbine)
    analyzed count
    367
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0000#groups/OG001
  3. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0001
    arm key
    OG000
    arm label
    Dato-DXd
    regimen
    Arm 1: Dato-DXd
    analyzed count
    365
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0001#groups/OG000
  4. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0001
    arm key
    OG001
    arm label
    Investigator's Choice of Chemotherapy (ICC)
    regimen
    Arm 2: ICC (Capecitabine or Gemcitabine or Eribulin mesylate or Vinorelbine)
    analyzed count
    367
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0001#groups/OG001
  5. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0002
    arm key
    OG000
    arm label
    Dato-DXd
    regimen
    Arm 1: Dato-DXd
    analyzed count
    365
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0002#groups/OG000
  6. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0002
    arm key
    OG001
    arm label
    Investigator's Choice of Chemotherapy (ICC)
    regimen
    Arm 2: ICC (Capecitabine or Gemcitabine or Eribulin mesylate or Vinorelbine)
    analyzed count
    367
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0002#groups/OG001
  7. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0003
    arm key
    OG000
    arm label
    Dato-DXd
    regimen
    Arm 1: Dato-DXd
    analyzed count
    133
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0003#groups/OG000
  8. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0003
    arm key
    OG001
    arm label
    Investigator's Choice of Chemotherapy (ICC)
    regimen
    Arm 2: ICC (Capecitabine or Gemcitabine or Eribulin mesylate or Vinorelbine)
    analyzed count
    84
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0003#groups/OG001
  9. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0004
    arm key
    OG000
    arm label
    Dato-DXd
    regimen
    Arm 1: Dato-DXd
    analyzed count
    134
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0004#groups/OG000
  10. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0004
    arm key
    OG001
    arm label
    Investigator's Choice of Chemotherapy (ICC)
    regimen
    Arm 2: ICC (Capecitabine or Gemcitabine or Eribulin mesylate or Vinorelbine)
    analyzed count
    81
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0004#groups/OG001
  11. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0005
    arm key
    OG000
    arm label
    Dato-DXd
    regimen
    Arm 1: Dato-DXd
    analyzed count
    365
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0005#groups/OG000
  12. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    outcome key
    om-0005
    arm key
    OG001
    arm label
    Investigator's Choice of Chemotherapy (ICC)
    regimen
    Arm 2: ICC (Capecitabine or Gemcitabine or Eribulin mesylate or Vinorelbine)
    analyzed count
    367
    analyzed unit
    Participants
    is comparator
    Source null
    source pointer
    NCT05104866-om-0005#groups/OG001
harms
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    harm key
    EG000
    source section id
    NCT05104866-ae
    event group key
    EG000
    event group label
    Dato-DXd
    serious affected
    62
    serious at risk
    360
    other affected
    348
    other at risk
    360
    frequency threshold
    5
    collection period
    Adverse Event data was collected from time of signature of informed consent until the follow-up period is completed (35 days after the last dose of study treatment) (maximum duration of approximately 28 months). All-Cause Mortality was assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
    event definition
    All-Cause Mortality was assessed in the Full Analysis Set (all randomised participants). Serious and Other adverse events were assessed in the Safety Analysis Population (all treated subjects)
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    harm key
    EG001
    source section id
    NCT05104866-ae
    event group key
    EG001
    event group label
    Investigator's Choice of Chemotherapy (ICC)
    serious affected
    67
    serious at risk
    351
    other affected
    329
    other at risk
    351
    frequency threshold
    5
    collection period
    Adverse Event data was collected from time of signature of informed consent until the follow-up period is completed (35 days after the last dose of study treatment) (maximum duration of approximately 28 months). All-Cause Mortality was assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
    event definition
    All-Cause Mortality was assessed in the Full Analysis Set (all randomised participants). Serious and Other adverse events were assessed in the Safety Analysis Population (all treated subjects)
    undenominated note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
quality of life
  1. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    qol key
    qol-0010
    source section id
    NCT05104866-om-0010
    source outcome index
    10
    instrument
    EORTC QLQ
    instrument basis
    matched 'eortc' in the study's own wording
    scale title
    Clinical Outcome Assessment- TTD in Pain
    measure definition
    Time to deterioration in pain as measured by the pain scale from EORTC QLQ-C30. Deterioration is defined as a 16.6 increase in score relative to baseline score
    time frame
    From date of randomization to 18 weeks post-progression. Assessments occur every 3 weeks then every 6 weeks until 18 weeks post-progression and at end of treatment visit. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
    analysis role
    secondary
    reporting status
    POSTED
    higher is better
    Source null
    direction quote
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  2. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    qol key
    qol-0011
    source section id
    NCT05104866-om-0011
    source outcome index
    11
    instrument
    EORTC QLQ
    instrument basis
    matched 'eortc' in the study's own wording
    scale title
    Clinical Outcome Assessment- TTD in Physical Functioning
    measure definition
    Time to deterioration in physical functioning as measured by the physical functioning scale from EORTC QLQ-C30. Deterioration is defined as a 13.3 decrease in score relative to baseline score.
    time frame
    From date of randomization to 18 weeks post-progression. Assessments occur every 3 weeks then every 6 weeks until 18 weeks post-progression and at end of treatment visit. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
    analysis role
    secondary
    reporting status
    POSTED
    higher is better
    Source null
    direction quote
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
  3. release id
    clinical-indications-draft-1
    disease state id
    ds-breast-cancer-femara-ea5f0363
    nct id
    NCT05104866
    qol key
    qol-0012
    source section id
    NCT05104866-om-0012
    source outcome index
    12
    instrument
    EORTC QLQ
    instrument basis
    matched 'eortc' in the study's own wording
    scale title
    Clinical Outcome Assessment- TTD in GHS
    measure definition
    Time to deterioration in global health status/QoL as measured by the global health status/QoL scale from EORTC QLQ-C30. Deterioration is defined as a 16.6 decrease in score relative to baseline score.
    time frame
    From date of randomization to 18 weeks post-progression. Assessments occur every 3 weeks then every 6 weeks until 18 weeks post-progression and at end of treatment visit. Assessed up to data cut-off (24Jul2024) to a maximum of approximately 33 months.
    analysis role
    secondary
    reporting status
    POSTED
    higher is better
    Source null
    direction quote
    Source null
    population note
    Source null
    curation status
    draft
    reviewed by
    Source null
    reviewed at
    Source null
    created at
    2026-09-10T00:00:00Z
setting source links

    Preserved source evidence · Not medical advice