Real-world Treatment Patterns and Effectiveness of Palbociclib and AI Therapy
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ClinicalTrials.gov Identifier: NCT04176354 |
Recruitment Status : Unknown
Verified May 2020 by Pfizer.
Recruitment status was: Active, not recruiting
First Posted : November 25, 2019
Last Update Posted : August 12, 2020
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Condition or disease | Intervention/treatment |
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Metastatic Breast Cancer | Drug: Palbociclib + an aromatase inhibitor Drug: Palbociclib + Letrozole Drug: Letrozole |
Study Type : | Observational |
Actual Enrollment : | 1 participants |
Observational Model: | Cohort |
Time Perspective: | Retrospective |
Official Title: | Real-world Treatment Patterns and Effectiveness of Palbociclib in Combination With an Aromatase Inhibitor as Initial Endocrine Based Therapy in Metastatic/Advanced Breast Cancer |
Actual Study Start Date : | October 27, 2019 |
Estimated Primary Completion Date : | October 27, 2021 |
Estimated Study Completion Date : | October 27, 2021 |

Group/Cohort | Intervention/treatment |
---|---|
Palbociclib + an aromatase inhibitor
Adult metastatic breast cancer patients who initiated Palbociclib + an aromatase inhibitor as first line therapy between Feb 3, 2015 to 3 months prior to date of data cutoff in the Flatiron Health Analytic Database.
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Drug: Palbociclib + an aromatase inhibitor
Palbociclib + an aromatase inhibitor therapy |
Palbociclib + Letrozole
Adult metastatic breast cancer patients who initiated Palbociclib +Letrozole as first line therapy between Feb 3, 2015 to 3 months prior to date of data cutoff in the Flatiron Health Analytic Database.
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Drug: Palbociclib + Letrozole
Palbociclib + Letrozole therapy |
Letrozole
Adult metastatic breast cancer patients who initiated Letrozole as first line therapy between Feb 3, 2015 to 3 months prior to date of data cutoff in the Flatiron Health Analytic Database.
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Drug: Letrozole
Letrozole monotherapy |
- Real-world progression free survival (rwPFS) [ Time Frame: From date of index treatment to death, disease progression, or end of study, whichever came first, assessed up to 52 months ]Median time (months) from index date to death, disease progression based on radiology, laboratory evidence, pathology, or clinical assessment until next line therapy, or end of the study, whichever came first, assessed up to 52 months
- Overall survival [ Time Frame: From date of index treatment until date of death from any acuse or date of end of study, whichever came first, assessed up to 52 months ]Median time (months) from date of index treatment to date of death. Patients who did not die in the study period are censored at their last date in the study.
- Real-world tumor response (rwTR) [ Time Frame: From date of index treatment to date of disease progression, date of death, or end of study whichever came first, assessed up to 52 months ]Real-world tumor response is defined as complete response or partial response, based on treating clinician's assessment of radiological evidence for change in burden of disease over the course of treatment
- Time to next line of therapy [ Time Frame: From date of index treatment to date of next line therapy, date of death, or end of study, whichever came first, assessed up to 52 months ]Median time (months) from date of index treatment to date of next line therapy, date of death, or end of study, whichever came first, assessed up to 52 months
- Time to first use of chemotherapy [ Time Frame: From date of index treatemnt to date of first use of chemotherapy, date of death, or end of study, whichever came first, assessed up to 52 months ]Median time (months) from date of index treatment to date of first use of chemotherapy, date of death, or end of study, whichever came first, assessed up to 52 months

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | No |
Sampling Method: | Non-Probability Sample |
Inclusion Criteria:
- Female sex
- At least 18 years old at MBC diagnosis
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Diagnosis of MBC at any point in patient history
- ICD-9 (174.x, 175.x) or ICD-10 (C50.xx) diagnosis of BC
- Confirmation of metastatic disease
- At least 2 document clinical visits
- Evidence of stage IV or recurrent MBC with a metastatic diagnosis date on or after 2011, as confirmed by unstructured clinical documents
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HR+/HER2-
- HR+: ER+ or PR+ test before or up to 60 days after MBC diagnosis
- HER2-: any HER2 negative test and the absence of a positive test (IHC positive 3+, FISH positive/amplified, Positive NOS) before or up to 60 days after MBC diagnosis
- Palbociclib + AI or letrozole as first-line therapy for MBC during the period from February/2015 through August /31/2018 (or 3 months prior to study cut-off date) to allow for a possible minimum follow-up time of 90 days until the study cutoff date. AI was administered within (±) 28 days of Palbociclib index date.
Exclusion Criteria:
- Evidence of prior treatment with other CDK4/6I (Ribociclib or Abemaciclib), AI (Letrozole, Exemestane, and Anastrazole), Tamoxifen, Raloxifene, Toremifene, or Fulvestrant for MBC
- First structured activity greater than 90 days after MBC diagnostic date
- Treatment with a CDK4/6 inhibitor as part of a clinical trial

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04176354
United States, New York | |
Pfizer | |
New York, New York, United States, 10017 |
Study Director: | Pfizer CT.gov Call Center | Pfizer |
Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: | Pfizer |
ClinicalTrials.gov Identifier: | NCT04176354 |
Other Study ID Numbers: |
A5481122 |
First Posted: | November 25, 2019 Key Record Dates |
Last Update Posted: | August 12, 2020 |
Last Verified: | May 2020 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
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. |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Product Manufactured in and Exported from the U.S.: | No |
Breast cancer Palbociclib Real-world data Retrospective study Effectiveness |
Breast Neoplasms Neoplasms by Site Neoplasms Breast Diseases Skin Diseases Letrozole Palbociclib Aromatase Inhibitors Antineoplastic Agents |
Steroid Synthesis Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Estrogen Antagonists Hormone Antagonists Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs Protein Kinase Inhibitors |