Comparative Real World Tumor Response in Pre-menopausal Metastatic Breast Cancer Patients Treated With Palbociclib + Aromatase Inhibitor or Aromatase Inhibitor Alone

REAL-WORLD TUMOR RESPONSE OF PALBOCICLIB IN COMBINATION WITH AN AROMATASE INHIBITOR AS FIRST-LINE THERAPY IN PRE/PERIMENOPAUSAL WOMEN WITH METASTATIC BREAST CANCER

This study aims to assess real-world tumor response in pre/perimenopausal HR+/HER2- metastatic breast cancer (MBC) patients initiating palbociclib + aromatase inhibitor (AI) or AI alone as first-line therapy during the period on or after 01 January 2010 to on or before 30 June 2020. Data will be obtained from structured data fields within an electronic health record (EHR) database and will be supplemented by additional unstructured data collected through a targeted chart review.

Study Overview

• Status: Completed
• Conditions: Metastatic Breast Cancer
• Intervention / Treatment: Drug: Palbociclib + aromatase inhibitor; Drug: Aromatase inhibitor

• Study Type: Observational
• Enrollment (Actual): 197

Contacts and Locations

Study Locations

• United States
  • New York
    • New York, New York, United States, 10017
      • Pfizer New York

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Probability Sample

Study Population

pre-menopausal metastatic breast cancer patients

Description

Inclusion Criteria:

1. Pre or perimenopausal at MBC diagnosis
2. Diagnosis of MBC in patient history
3. Confirmed HR+/HER2- status as defined as: a. HR+: ER+ or PR+ test; b. HER2-: any HER2 negative test and the absence of a positive test (IHC positive 3+, fluorescence in situ hybridization [FISH] positive/amplified, positive not otherwise specified [NOS]).

4. Received one of the following regimens as first-line treatment for MBC during the period from 01 January 2010 through index period 30 June 2020 until the data cutoff date of 31 December 2020.

   1. Palbociclib + AI as first-line treatment for MBC or
   2. Monotherapy AI as first-line treatment for MBC
5. Received care at a US Oncology Network (USON) site(s) utilizing the full EHR capacities of iKnowMed (iKM) at the time of treatment.
6. EHR data available from the USON site(s) where the patient received treatment are accessible for research purposes.

Exclusion Criteria:

1. Evidence of prior treatment with cyclin-dependent kinase (CDK) 4/6 inhibitors (palbociclib, ribociclib or abemaciclib) in the early breast cancer (BC) or MBC setting.
2. First structured activity (clinical visit) greater than 120 days after MBC diagnostic date with chart review to confirm no initial MBC treatment outside USON.
3. Receipt of treatment indicated for another primary cancer during the study observation period (after initiation of Palbociclib + AI or AI monotherapy and before 31 December 2020) or history of another primary cancer within USON.
4. Enrolled in any interventional clinical trial after initiation of Palbociclib + AI or AI monotherapy AND before 31 December 2020.

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Palbociclib + aromatase inhibitor	Drug: Palbociclib + aromatase inhibitor; Palbociclib + aromatase inhibitor
Aromatase inhibitor alone	Drug: Aromatase inhibitor; Aromatase inhibitor

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Real World Tumor Response (rwTR) of All Participants (Adjusted by Normalized Inverse Probability of Treatment Weighting [nIPTW])	rwTR of complete response (CR) or partial response (PR) based on response assessments captured with chart review during first line therapy. Real-world response rate (rwRR) was estimated using nIPTW method to adjust for the potential imbalance between the 2 treatment cohorts. CR was documented as 'a complete response' to therapy, indication patient is in 'remission', 'all lesions' have disappeared, or 'no evidence of disease'. PR was documented as partial reduction in size of visible disease in some or all areas without any areas of increase in visible disease (decrease in disease volume even though disease is still present). nIPTW method was employed to reduce confounding due to potential selection biases.	11 Years. From 01 January 2010 to 30 June 2020 were assessed. The study data cutoff date was on 31 December 2020.
Real World Tumor Response in Patients With Tumor Assessment (Adjusted by nIPTW)	rwTR of complete CR or PR based on response assessments captured with chart review during first line therapy. rwRR was estimated using nIPTW method to adjust for the potential imbalance between the 2 treatment cohorts. CR was documented as 'a complete response' to therapy, indication patient is in 'remission', 'all lesions' have disappeared, or 'no evidence of disease'. PR was documented as partial reduction in size of visible disease in some or all areas without any areas of increase in visible disease (decrease in disease volume even though disease is still present). nIPTW method was employed to reduce confounding due to potential selection biases.	11 Years. From 01 January 2010 to 30 June 2020 were assessed. The study data cutoff date was on 31 December 2020.

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): July 16, 2021
• Primary Completion (Actual): December 9, 2021
• Study Completion (Actual): December 9, 2021

Study Registration Dates

• First Submitted: August 12, 2021
• First Submitted That Met QC Criteria: August 12, 2021
• First Posted (Actual): August 19, 2021

Study Record Updates

• Last Update Posted (Actual): October 8, 2024
• Last Update Submitted That Met QC Criteria: July 5, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Keywords: aromatase inhibitor; palbociclib; pre-menopausal
• Additional Relevant MeSH Terms: Skin Diseases; Neoplasms; Neoplasms by Site; Breast Diseases; Breast Neoplasms; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Enzyme Inhibitors; Antineoplastic Agents; Hormones, Hormone Substitutes, and Hormone Antagonists; Protein Kinase Inhibitors; Hormone Antagonists; Steroid Synthesis Inhibitors; Estrogen Antagonists; Palbociclib; Aromatase Inhibitors
• Other Study ID Numbers: A5481159

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.