Study to Compare Overall Survival in Medicare Patients With Metastatic Breast Cancer Treated With a Medicine Called Palbociclib in Combination With Aromatase Inhibitor and Aromatase Inhibitor by Itself.

NCT06086340 | Completed Results FDA Drug

• 2 other identifiers: A5481182Henri 3
• Study Type: observational
• Target: 779
• Locations: 1 country
• Sites: 1

Brief Summary

A retrospective study of de-identified (to preserve patient privacy) patient information from the SEER-Medicare Database to compare overall survival of first line palbociclib + aromatase inhibitor (AI) therapy versus AI therapy alone treatment in women or men aged 65 and older with newly diagnosed hormone receptor positive/human epidermal growth factor receptor 2 negative (HR+/HER2-) metastatic breast cancer (MBC) in the United States

Conditions

Breast Cancer

Keywords

Breast neoplasm; Hormone receptor-positive Human epidermal growth factor receptor 2 negative (HR+,HER2-); palbociclib; Metastatic; Medicare; SEER-Medicare

Outcome Measures

Primary Outcomes (2)

• Overall Survival According to Unadjusted Analysis

  Overall survival was defined as time in months from the study index date to all cause death. Study index date in this outcome measure was the date of first line of treatment initiation with palbociclib + AI or AI alone after the de novo mBC diagnosis. De novo mBC referred to breast cancer that physician diagnosed for the first time after it had already spread outside of the breast to distant parts of the body. Unadjusted analysis: analysis not considering any covariates, specifically potential differences in baseline characteristics that could confound the association between treatment and survival. Overall survival was assessed using Kaplan-Meier analysis.

  From index date to death (approximately 69.9 months); retrospective data evaluated in 4 months (approximately) of this study

• Overall Survival According to Stabilized Inverse Probability of Treatment Weighted (sIPTW) Analysis

  Overall survival was defined as time in months from the study index date to all cause death. Study index date in this outcome measure was the date of first line of treatment initiation with palbociclib + AI or AI alone after the de novo mBC diagnosis. De novo mBC referred to breast cancer that physician diagnosed for the first time after it had already spread outside of the breast to distant parts of the body. sIPTW analysis: stabilized inverse probability treatment weighting. This is a statistical method that reweights participants to create groups with similar baseline characteristics. The analysis therefore adjusts for differences in baseline characteristics that could confound the association between treatment and survival. Overall survival was assessed using Kaplan-Meier analysis.

  From index date to death (approximately 69.9 months); retrospective data evaluated in 4 months (approximately) of this study

Study Arms (2)

Palbociclib + AI

Adult metastatic breast cancer patients who initiated Palbociclib + an aromatase inhibitor as first line therapy in SEER-Medicare

Drug: Palbociclib; Drug: Aromatase Inhibitor

AI alone

Adult metastatic breast cancer patients who initiated an aromatase inhibitor (alone) as first line therapy

Drug: Aromatase Inhibitor

Interventions

Palbociclib DRUG

Palbociclib with an aromatase inhibitor therapy

Also known as: Ibrance

Palbociclib + AI

Aromatase Inhibitor DRUG

Aromatase Inhibitor Therapy

Also known as: letrozole, anastrozole, exemestane

AI alone; Palbociclib + AI

Eligibility Criteria

• Age: 65 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Medicare recipients with HR+/HER2- with De Novo metastatic breast cancer

You may qualify if:

• De novo metastatic (stage IV) disease at initial breast cancer diagnosis during 2015-2019
• HR+/HER2- molecular subtype at diagnosis
• Initiated 1L systemic therapy with palbociclib + AI or AI alone

You may not qualify if:

• Patients will be excluded if their metastatic breast cancer diagnosis was first recorded in a death certificate or at the time of autopsy.

Sponsors & Collaborators

• Pfizer: lead

Study Sites (1)

Pfizer New York

New York, New York, 10001, United States

Location

Related Publications (1)

• Brufsky AM, Sandin R, Stergiopoulos S, Chen C, Karanth S, Li B, Esterberg E, Makari D, Candrilli SD, Goyal RK, Rugo HS. Overall Survival With Palbociclib and Aromatase Inhibitor Versus Aromatase Inhibitor Alone in Older Patients With HR+/HER2- Metastatic Breast Cancer. Cancer Med. 2025 Apr;14(7):e70719. doi: 10.1002/cam4.70719.

  PMID: 40145289 DERIVED

Related Links

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

MeSH Terms

Conditions

Breast Neoplasms; Neoplasm Metastasis

Interventions

palbociclib; Aromatase Inhibitors; Letrozole; Anastrozole; exemestane

Condition Hierarchy (Ancestors)

Neoplasms by Site; Neoplasms; Breast Diseases; Skin Diseases; Skin and Connective Tissue Diseases; Neoplastic Processes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Steroid Synthesis Inhibitors; Enzyme Inhibitors; Molecular Mechanisms of Pharmacological Action; Pharmacologic Actions; Chemical Actions and Uses; Estrogen Antagonists; Hormone Antagonists; Hormones, Hormone Substitutes, and Hormone Antagonists; Physiological Effects of Drugs; Nitriles; Organic Chemicals; Triazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Results Point of Contact

• Title: Pfizer ClinicalTrials.gov Call Center
• Organization: Pfizer Inc.

ClinicalTrials.gov_Inquiries@pfizer.com

1-800-718-1021

Study Officials

• Pfizer CT.gov Call Center

  Pfizer

  STUDY DIRECTOR

Publication Agreements

• PI is Sponsor Employee: No
• Restriction Type: OTHER
• Restrictive Agreement: Yes

Study Design

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

Study Record Dates

• First Submitted: October 11, 2023
• First Posted: October 17, 2023
• Study Start: September 29, 2023
• Primary Completion: January 24, 2024
• Study Completion: January 24, 2024
• Last Updated: November 18, 2025
• Results First Posted: November 18, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)