Real-World Effectiveness of Palbociclib in Combination With an Aromatase Inhibitor
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ClinicalTrials.gov Identifier: NCT05361655 |
Recruitment Status :
Recruiting
First Posted : May 5, 2022
Last Update Posted : May 5, 2022
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Condition or disease | Intervention/treatment |
---|---|
Metastatic Breast Cancer | Drug: Palbociclib + an aromatase inhibitor Drug: Aromatase inhibitor |
Study Type : | Observational |
Estimated Enrollment : | 3000 participants |
Observational Model: | Cohort |
Time Perspective: | Retrospective |
Official Title: | Real-World Treatment Effectiveness of Palbociclib in Combination With an Aromatase Inhibitor as 1st Line Therapy in Metastatic Breast Cancer |
Actual Study Start Date : | September 1, 2021 |
Estimated Primary Completion Date : | September 20, 2022 |
Estimated Study Completion Date : | December 31, 2023 |

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 March 31, 2020 in the Flatiron Health Analytic Database.
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Drug: Palbociclib + an aromatase inhibitor
Palbociclib + an aromatase inhibitor therapy |
Aromatase inhibitor
Adult metastatic breast cancer patients who initiated an aromatase inhibitor as first line therapy between Feb 3, 2015 to March 31, 2020 in the Flatiron Health Analytic Database.
|
Drug: Aromatase inhibitor
Aromatase inhibitor therapy |
- Overall survival [ Time Frame: From date of index treatment until date of death from any cause or end of study, whichever came first, assessed up to 68 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 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 68 months ]rwPFS2 is the number of months from start of palbociclib + AI or AI alone to disease progression (based on clinical assessment or by radiographic scan/tissue biopsy) on the 2nd line of therapy or death from any cause, whichever occurred first
- Real-world tumor responses (rwTR) [ Time Frame: From date of index treatment to death, disease progression, or end of study, whichever came first, assessed up to 68 months ]Real-world best responses are assessed based on treating clinician's assessment of radiological evidence for change in burden of disease over the course of treatment after 1 month of index treatment initiation
- Initial dose of palbociclib [ Time Frame: From date of index treatment up to 68 months ]Describe initial dose of palbociclib treatment pattern
- Time to dose adjustment [ Time Frame: From date of index treatment to dose adjustment, assessed up to 68 months ]
- Duration of treatment [ Time Frame: From date of index treatment to end of the treatment, death, or end of study, whichever came first, assessed up to 68 months ]
- Time to subsequent treatments [ Time Frame: From date of index treatment to subsequent treatment, death, or end of study, whichever came first, assessed up to 68 months ]
- Time to chemotherapy [ Time Frame: From date of index treatment to subsequent chemotherapy, death, or end of study, whichever came first, assessed up to 68 months ]

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Ages Eligible for Study: | 18 Years to 99 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Sampling Method: | Non-Probability Sample |
Inclusion Criteria:
- Confirmed HR+/HER2- status after MBC diagnosis.
- Received palbociclib + AI or AI as first-line therapy
Exclusion Criteria:
- Evidence of prior treatment with other CDK4/6I, AI, 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): NCT05361655
Contact: Pfizer CT.gov Call Center | 1-800-718-1021 | ClinicalTrials.gov_Inquiries@pfizer.com |
United States, New York | |
10017 | Recruiting |
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: | NCT05361655 |
Other Study ID Numbers: |
A5481151 |
First Posted: | May 5, 2022 Key Record Dates |
Last Update Posted: | May 5, 2022 |
Last Verified: | May 2022 |
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. |
cyclin-dependent kinase 4/6i (CDK4/6i) |
Breast Neoplasms Neoplasms by Site Neoplasms Breast Diseases Skin Diseases Palbociclib Aromatase Inhibitors Antineoplastic Agents |
Protein Kinase Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action Steroid Synthesis Inhibitors Estrogen Antagonists Hormone Antagonists Hormones, Hormone Substitutes, and Hormone Antagonists Physiological Effects of Drugs |