Amcenestrant (SAR439859) Plus Palbociclib as First Line Therapy for Patients With ER (+) HER2(-) Advanced Breast Cancer
Public ClinicalTrials.gov record NCT04478266. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.
Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.
Official title
A Randomized, Multicenter, Double-blind Phase 3 Study of Amcenestrant (SAR439859) Plus Palbociclib Versus Letrozole Plus Palbociclib for the Treatment of Patients With ER (+), HER2 (-) Breast Cancer Who Have Not Received Prior Systemic Anti-cancer Treatment for Advanced Disease
Brief summary
Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.
Primary Objective: To determine whether Amcenestrant (SAR439859) in combination with palbociclib improves progression free survival (PFS) when compared with letrozole in combination with palbociclib in participants with estrogen receptor positive (ER+), human epidermal growth factor receptor 2 negative (HER2-) advanced breast cancer who have not received any prior systemic anticancer therapies for advanced disease. Secondary Objective: * To compare the overall survival in both treatment arms. * To evaluate the objective response rate in both treatment arms. * To evaluate the duration of response in both treatment arms. * To evaluate the clinical benefit rate in both treatment arms. * To evaluate progression-free survival on next line of therapy. * To evaluate the pharmacokinetics of amcenestrant, and palbociclib. * To evaluate health-related quality of life in both treatment arms. * To evaluate the time to first chemotherapy in both treatment arms. * To evaluate safety in both treatment arms.
Study identification
- NCT ID
- NCT04478266
- Recruitment status
- Terminated
- Study type
- Interventional
- Phase
- Phase 3
- Enrollment
- 1,068 participants
Conditions and interventions
Conditions
Interventions
- Amcenestrant-matching placebo Drug
- SAR439859 Drug
- Palbociclib Drug
- Letrozole Drug
- Goserelin Drug
- Letrozole-matching placebo Drug
Drug
Eligibility (public fields only)
- Age range
- 18 Years and older
- Sex
- All
- Healthy volunteers
- Healthy volunteers not accepted
This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.
Study timeline
- Start date
- Oct 14, 2020 (Actual)
- Primary completion
- Jun 28, 2022 (Actual)
- Completion
- May 26, 2023 (Actual)
- Last update posted
- Sep 11, 2025
2020 – 2023
United States locations
- U.S. sites
- 45
- U.S. states
- 22
- U.S. cities
- 43
| Facility | City | State | ZIP | Site status |
|---|---|---|---|---|
| Investigational Site Number :8400075 | Daphne | Alabama | 36526 | — |
| Investigational Site Number :8400083 | Glendale | Arizona | 85308 | — |
| Investigational Site Number :8400066 | Tucson | Arizona | 85712 | — |
| Investigational Site Number :8400038 | Fullerton | California | 92835 | — |
| Investigational Site Number :8400056 | Los Alamitos | California | 90720 | — |
| Investigational Site Number :8400029 | Santa Monica | California | 90404 | — |
| Investigational Site Number :8400025 | Denver | Colorado | 80262 | — |
| Investigational Site Number :8400059 | Lakeland | Florida | 33805 | — |
| Investigational Site Number :8400053 | Orlando | Florida | 32804 | — |
| Investigational Site Number :8400081 | Palm Bay | Florida | 32901 | — |
| Investigational Site Number :8400055 | Athens | Georgia | 30607 | — |
| Investigational Site Number :8400016 | Atlanta | Georgia | 30342 | — |
| Investigational Site Number :8400034 | Savannah | Georgia | 31405 | — |
| Investigational Site Number :8400035 | Thomasville | Georgia | 31792 | — |
| Investigational Site Number :8400039 | Chicago | Illinois | 60612 | — |
| Investigational Site Number :8400008 | Fort Wayne | Indiana | 46804 | — |
| Investigational Site Number :8400006 | Iowa City | Iowa | 52242 | — |
| Investigational Site Number :8400013 | Westwood | Kansas | 66205-2003 | — |
| Investigational Site Number :8400028 | Scarborough | Maine | 04074-9308 | — |
| Investigational Site Number :8400017 | Boston | Massachusetts | 02114 | — |
| Investigational Site Number :8400076 | Danvers | Massachusetts | 01923 | — |
| Investigational Site Number :8400077 | Newton | Massachusetts | 02463 | — |
| Investigational Site Number :8400002 | Ann Arbor | Michigan | 48109 | — |
| Investigational Site Number :8400005 | Kansas City | Missouri | 64111 | — |
| Investigational Site Number :8400004 | St Louis | Missouri | 63141 | — |
| Investigational Site Number :8400058 | Las Vegas | Nevada | 89102 | — |
| Investigational Site Number :8400015 | New Brunswick | New Jersey | 08901-1914 | — |
| Investigational Site Number :8400024 | Paramus | New Jersey | 00000 | — |
| Investigational Site Number :8400010 | New York | New York | 10016 | — |
| Investigational Site Number :8400023 | Stony Brook | New York | 11794-8121 | — |
| Investigational Site Number :8400009 | Winston-Salem | North Carolina | 27157 | — |
| Investigational Site Number :8400067 | Tigard | Oregon | 97223 | — |
| Investigational Site Number :8400001 | Pittsburgh | Pennsylvania | 15232 | — |
| Investigational Site Number :8400073 | Austin | Texas | 78745 | — |
| Investigational Site Number :8400072 | Dallas | Texas | 75231 | — |
| Investigational Site Number :8400070 | Dallas | Texas | 75246 | — |
| Investigational Site Number :8400080 | Denton | Texas | 76021 | — |
| Investigational Site Number :8400061 | Houston | Texas | 77024 | — |
| Investigational Site Number :8400068 | Houston | Texas | 77024 | — |
| Investigational Site Number :8400084 | Plano | Texas | 75093 | — |
| Investigational Site Number :8400086 | The Woodlands | Texas | 77380 | — |
| Investigational Site Number :8400078 | Waco | Texas | 76712 | — |
| Investigational Site Number :8400082 | Webster | Texas | 77598 | — |
| Investigational Site Number :8400085 | Blacksburg | Virginia | 24060 | — |
| Investigational Site Number :8400069 | Winchester | Virginia | 22601 | — |
Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.
Non-U.S. locations
This page focuses on the U.S. directory. The official record also lists 204 non-U.S. sites.
About this trial record page
- What this page shows
- Public field values for ClinicalTrials.gov record NCT04478266, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
- What this page does not do
- No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
- Where the data comes from
- Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
- Last refresh
- Last update posted Sep 11, 2025 · Synced Oct 17, 2026
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Open the official record
The complete public registry record, listed eligibility criteria, and available contact information for NCT04478266 live on ClinicalTrials.gov.