Treatment Patterns and Clinical Outcomes Among Talazoparib-Treated Adults With HER2-Negative mBC With gBRCA1/2m

Treatment Patterns and Clinical Outcomes Among Talazoparib-Treated Adults With HER2-Negative Metastatic Breast Cancer and Germline BRCA1/2 Mutations: An Observational Study Using Flatiron Electronic Health Record (EHR) Database

This non-interventional retrospective study will describe real-world treatment patterns and clinical outcomes among adults with HER2-negative metastatic breast cancer with germline BRCA1/2 mutations who initiated talazoparib as a first or later line of therapy. Patients will be identified from the Flatiron Electronic Health Record database.

Inclusion Criteria:

Patients must meet all of the following inclusion criteria to be eligible for inclusion in the study:

• Diagnosed with breast cancer (ICD-9 174.x or 175.x or ICD-10 C50x)
• At least two visits in the Flatiron database on or after January 1, 2011
• Pathology consistent with breast cancer
• Has evidence of stage IV or recurrent metastatic breast cancer with a metastatic diagnosis date on or after January 1, 2011. This includes patients who were diagnosed with stage IV at diagnosis or were diagnosed with earlier stage disease, then developed a distant metastasis later on, or had recurrence of the disease via a distant metastasis
• Confirmed receipt of talazoparib as treatment for mBC via abstraction initiated between January 1, 2018 and September 30, 2020
• HER2 negative test result on or before the start of patient's first talazoparib-containing line of therapy, as defined by Flatiron's line of therapy rules
• BRCA1, BRCA2, BRCA1 and BRCA2 germline mutation, or BRCA germline mutation not otherwise specified, identified on or before the start date of patient's first talazoparib-containing line of therapy, as defined by Flatiron's line of therapy business rules
• Age 18 years or older at the time of first talazoparib-containing line of therapy

Exclusion Criteria:

• Lacking relevant unstructured documents in the Flatiron database for review by the abstraction team
• Receipt of drug as part of a clinical trial (captured in the database as "clinical study drug" without additional information about active ingredient or whether the patient received placebo), defined as any non-cancelled order, administration, or oral episode for a drug used in a clinical trial, on or prior to start of first talazoparib line of therapy, as defined by Flatiron's line of therapy business rules