Amcenestrant (SAR439859) Plus Palbociclib as First Line Therapy for Patients With ER (+) HER2(-) Advanced Breast Cancer


Brief Summary

Primary Objective:

To determine whether Amcenestrant (SAR439859) in combination with palbociclib improvesprogression free survival (PFS) when compared with letrozole in combination with palbociclib in participants with ER+, 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

Primary Purpose
Study Type
Phase III


Healthy Volunteers
Minimum Age
18 Years
Maximum Age

Inclusion criteria :

  • Adult participants with loco-regional recurrent or metastatic disease not amenable to curative treatment
  • Confirmed diagnosis of ER+/HER2- breast cancer
  • No prior systemic treatment for loco-regional recurrent or metastatic disease
  • Measurable disease evaluable per Response Evaluation Criterion in Solid Tumors (RECIST) v.1.1 or non-measurable bone-only disease
  • Eastern Cooperative Oncology Group (ECOG) performance status 0-2
  • Participants should be willing to provide tumor tissue
  • Capable of giving informed consent

Exclusion criteria:

  • Known active brain metastases
  • Prior neo (adjuvant) treatment with any selective estrogen receptor degrader (SERD)
  • Inadequate organ and marrow function
  • Disease recurrence while on, or within 12 months of completion of (neo)adjuvant endocrine therapy
  • Pregnant, breastfeeding, or woman of child bearing potential unwilling to use recommended contraception methods
  • Male participants who disagree to follow contraception
  • Participants with advanced, symptomatic visceral spread, that are at risk of life-threatening complications in the short term
  • Participants with significant concomitant illness The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.

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Study Stats
Protocol No.
Monica Rocha
  • TRIO-US - Los Alamitos CA
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