C4891034 Trial (JCP144)

Real-World Patient-Reported Outcomes in ER+/HER2- Advanced/Metastatic Breast Cancer

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Population: ER+/HER2- mBC

Line of therapy: 2L (after prior 1L treatment with CDK4/6i)

Intervention: Non-interventional (PROs at 5 timepoints)

Key Inclusion Criteria

1. ≥18 years old.

2. Confirmed ER+/HER2- ABC/mBC whose disease progressed after prior 1L treatment with CDK4/6i.

3. Due to initiate 2L treatment on either:

   o Endocrine therapy (ET) (with no additional targeted therapy prescribed)

   o Targeted therapy (with or without ET).

4. Evidence of a personally signed and dated informed consent document indicating that the patient (or a legally acceptable representative) has been informed of all pertinent aspects of the study.

   
   

Key Exclusion Criteria

1. Participating in a randomized clinical trial at the point of enrollment.

Scheduled to initiate other types of treatment: chemotherapy, rechallenge with CDK4/6i (i.e., receive a CDK4/6i in 2L after prior progression on 1L CDK), BRCA1/2m targeted therapies (e.g. PARP inhibitors), HER2-low targeted therapies, or investigational drugs.

Sponsor: Pfizer

CRP Contact: aida.salehi@ladydavis.ca

CRP PI: Dr. C. Ferrario

Status: Open to accrual