A Study to Learn About the Safety of TALZENNA for the Treatment of Breast Cancer

TALZENNA Capsules Special Investigation - Investigation on BRCA Mutation-Positive and HER2-Negative Unresectable or Recurrent Breast Cancer With a History of Cancer Chemotherapy -

The purpose of this study is to learn about the safety of TALZENNA for the patients with breast cancer that cannot be removed by surgery and has come back. These participants also have a past treatment with medicines that try to stop the growth of cancer cells.

This study is seeking for participants who:

• have breast cancer that cannot be removed by surgery and has come back
• have not used this medicine before. All patients in this study will receive TALZENNA according to the prescriptions.

Patients will be followed up to 52 weeks (12 months) from the day of start of treatment start (Day 1). However, in cases where treatment has been completed or stopped less than 52 weeks (12 months) after the start of giving study medicine, the participants will be checked until completion (discontinuation) of treatment.

Study Overview

• Status: Active, not recruiting
• Conditions: Breast Cancer

• Study Type: Observational
• Enrollment (Actual): 3

Contacts and Locations

Study Locations

• Japan
  • Tokyo, Japan
    • Pfizer Japan

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

Patients who satisfy the inclusion criteria

Description

Inclusion Criteria:

• Patients with BRCA mutation-positive and HER2- negative unresectable or recurrent breast cancer with a history of cancer chemotherapy
• No history of previous use of this drug

Exclusion Criteria:

• None

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of adverse drug reactions	For adverse drug reactions corresponding to myelosuppression, interstitial lung disease, thromboembolism, and secondary malignant tumour, the incidence, time of onset, grade, outcome etc. will be tabulated.	Up to 52 weeks

Collaborators and Investigators

• Sponsor: Pfizer
• Investigators: Study Director: Pfizer CT.gov Call Center, Pfizer

Publications and helpful links

Helpful Links

• To obtain contact information for a study center near you, click here.

Study record dates

Study Major Dates

• Study Start (Actual): April 12, 2025
• Primary Completion (Estimated): March 30, 2029
• Study Completion (Estimated): March 30, 2029

Study Registration Dates

• First Submitted: December 11, 2024
• First Submitted That Met QC Criteria: December 11, 2024
• First Posted (Actual): December 16, 2024

Study Record Updates

• Last Update Posted (Actual): November 17, 2025
• Last Update Submitted That Met QC Criteria: November 13, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: BRCA mutation-positive and HER2-negative; unresectable or recurrent breast cancer
• Additional Relevant MeSH Terms: Neoplasms by Site; Neoplasms; Skin Diseases; Breast Diseases; Skin and Connective Tissue Diseases; Breast Neoplasms
• Other Study ID Numbers: C3441045

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical_trials/trial_data_and_results/data_requests.