A Study to Understand About the Study Medicine Palbociclib in Breast Cancer Patients After it is Out in the Japanese Market

NCT07096024 | Completed

• 1 other identifier: A5481117
• Study Type: observational
• Target: 1,772
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of the study is to:

• compare the chances of getting interstitial lung disease (ILD) in new users of palbociclib plus fulvestrant to new users of fulvestrant alone (using data from before palbociclib was out in the market)
• look into the factors that can cause ILD in new users of palbociclib. This study uses patient data without giving out any personal information of the patient. This data is taken from a hospital-based claims database of the MDV database, that includes data from more than 400 hospitals in Japan. This study will use data of patients who are:
• diagnosed with breast cancer that include newly treated with palbociclib and/or other endocrine-based therapies for inoperable or recurrent breast cancer between 25 November 2011 and 30 November 2024.

Conditions

Breast Neoplasms

Keywords

Ibrance; Post-Marketing Database Study; Incidence of interstitial lung disease (ILD); inoperable or recurrent breast cancer; palbociclib; Medical Data Vision (MDV)

Outcome Measures

Primary Outcomes (4)

• The hazard ratios of ILD in palbociclib plus fulvestrant to new users of fulvestrant alone

  25 November 2011 and 30 September 2024

• The rate ratios of ILD in palbociclib plus fulvestrant to new users of fulvestrant alone

  25 November 2011 and 30 September 2024

• The rate differences of ILD in palbociclib plus fulvestrant to new users of fulvestrant alone

  25 November 2011 and 30 September 2024

• The incidence rate of ILD by each risk factor in new users of palbociclib

  25 November 2011 and 30 September 2024

Secondary Outcomes (1)

• The incidence rate of ILD by each risk factor in new users of endocrine-based therapies including combination with CDK4/6 inhibitors

  25 November 2011 and 30 September 2024

Study Arms (2)

New prescription of palbociclib with fulvestrant.

Patients treated with the combination of palbociclib and fulvestrant

Drug: palbociclib plus fulvestrant; Drug: fulvestrant

New prescription of fulvestrant monotherapy before the launch of palbociclib

Patients treated with fulvestrant alone

Drug: fulvestrant

Interventions

palbociclib plus fulvestrant DRUG

Patients treated with the combination of palbociclib and fulvestrant

Also known as: Ibrance, fulvestrant

New prescription of palbociclib with fulvestrant.

fulvestrant DRUG

Patients treated with fulvestrant alone

New prescription of fulvestrant monotherapy before the launch of palbociclib; New prescription of palbociclib with fulvestrant.

Eligibility Criteria

• Age: 15 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)
• Sampling Method: Probability Sample

Study Population

The source population comprises patients diagnosed with breast cancer that include newly treated with palbociclib and/or other endocrine-based therapies for inoperable or recurrent breast cancer between 25 November 2011 and 31 December 2024

You may qualify if:

• Having prescription records of drugs for endocrine therapy (aromatase inhibitors, SERDs, SERMs, and CDK4/6 inhibitors) from 25 November 2011 to 31 December 2024.
• Having any breast cancer records with definitive diagnosis in the same month as the first prescription date.
• Having any records in MDV database on or before 6 months prior to the first prescription date (\<= -180 days: first prescription date = 0 day).
• Having any records in MDV database within 6 months prior to the first prescription date (-180 days to 0 day).

You may not qualify if:

• Having any records of anti-HER2 medication (e.g., trastuzumab, pertuzumab, lapatinib or trastuzumab emtansine) from 25 November 2011 to 31 December 2024.
• Having any records of second primary cancer with definitive diagnosis

Sponsors & Collaborators

• Pfizer: lead

Study Sites (1)

Pfizer New York

New York, New York, 10001, United States

Location

MeSH Terms

Conditions

Breast Neoplasms

Interventions

palbociclib; Fulvestrant

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases

Intervention Hierarchy (Ancestors)

Estradiol; Estrenes; Estranes; Steroids; Fused-Ring Compounds; Polycyclic Compounds; Estradiol Congeners; Gonadal Steroid Hormones; Gonadal Hormones; Hormones; Hormones, Hormone Substitutes, and Hormone Antagonists

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: RETROSPECTIVE
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 24, 2025
• First Posted: July 31, 2025
• Study Start: January 21, 2025
• Primary Completion: February 7, 2025
• Study Completion: February 7, 2025
• Last Updated: August 28, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)