Phase 2 Study of Amcenestrant (SAR439859) Versus Physician's Choice in Locally Advanced or Metastatic ER-positive Breast Cancer

Official Title

An Open Label Randomized Phase 2 Trial of Amcenestrant (SAR439859), Versus Endocrine Monotherapy as Per Physician's Choice in Patients With Estrogen Receptor-positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer With Prior Exposure to Hormonal Therapies


Primary Objective: To determine whether amcenestrant per os improves progression free survival (PFS) when compared with a endocrine monotherapy of the choice of the physician, in participants with metastatic or locally advanced breast cancer Secondary Objectives: - To compare the overall survival in the 2 treatment arms - To assess the objective response rate in the 2 treatment arms - To evaluate the disease control rate in the 2 treatment arms - To evaluate the clinical benefit rate in the 2 treatment arms - To evaluate the duration of response in the 2 treatment arms - To evaluate the PFS according to the estrogen receptor 1 gene (ESR1) mutation status in the 2 treatment arms - To evaluate the pharmacokinetics of amcenestrant as single agent - To evaluate health related quality of life in the 2 treatment arms - To compare the overall safety profile in the 2 treatment arms

Trial Description

Primary Outcome:

  • Progression free survival (PFS)
Secondary Outcome:
  • Overall Survival (OS)
  • Objective Response Rate (ORR)
  • Disease Control Rate (DCR)
  • Clinical Benefit Rate (CBR)
  • Duration of Response (DOR)
  • PFS according to (ESR1) mutation status
  • Assessments of the pharmacokinetic (PK) parameter of amcenestrant as single agent: plasma concentrations
  • Patient Reported Outcome (PRO) - health-related quality of life and health status using the European Quality of Life-5 Dimensions (EQ-5D)
  • Patient Reported Outcome (PRO) - the European Organisation for Research and Treatment of Cancer core quality of life questionnaire (EORTC-QLQ-C30)
  • Patient Reported Outcome (PRO) - EORTC-QLQ breast cancer (EORTC-QLQ-BR23)
  • Overall safety profile - Treatment-Emergent Adverse events
The duration of the study for an individual participant will include a period to assess eligibility (screening period) of up to 4 weeks (28 days), a treatment period of at least 1 cycle (28 days of study treatment), and an end of treatment (EOT) visit at least 30 days (or until the participant receive another anticancer therapy, whichever is earlier) following the last administration of study treatment. Study treatment may continue until precluded by unacceptable toxicity, disease progression, death or upon participant's request. An extension of recruitment for Chinese participants is planned in this study: After completion of randomization in the global part of the study, randomization will continue in China until approximately 90 Chinese participants are randomized.

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