Clinical trial · Observational
Real-world Treatment Patterns and Effectiveness of Palbociclib and AI Therapy
Real-world Treatment Patterns and Effectiveness of Palbociclib in Combination With an Aromatase Inhibitor as Initial Endocrine Based Therapy in Metastatic/Advanced Breast Cancer
NCT04176354CI-TRIAL-00080135completedResults postedClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
A retrospective observational analysis of de-identified Flatiron Health Analytic Database to describe patient characteristics, treatment patterns and effectiveness of Palbociclib + AI as first-line therapy in HR+/HER2- metastatic breast cancer (MBC) in the US clinical practices.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Metastatic Breast Cancer | Malignant Breast Neoplasm | CURATED_BROADER | 0.78 |
Interventions
Interventions (3)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Letrozole | Drug | Letrozole | ALIAS |
| Palbociclib + an aromatase inhibitor | Drug | — | UNRESOLVED |
| Palbociclib + Letrozole | Drug | — | UNRESOLVED |
Design
Arms and outcomes
Arms (3)
- label
- Palbociclib + an aromatase inhibitor
- description
- 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.
- interventionNames
- Drug: Palbociclib + an aromatase inhibitor
- label
- Palbociclib + Letrozole
- description
- 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.
- interventionNames
- Drug: Palbociclib + Letrozole
- label
- Letrozole
- description
- 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.
Eligibility
Eligibility (as posted)
- Sex
- Female
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: 1. Female sex 2. At least 18 years old at MBC diagnosis 3. Diagnosis of MBC at any point in patient history 1. ICD-9 (174.x, 175.x) or ICD-10 (C50.xx) diagnosis of BC 2. Confirmation of metastatic disease 3. At least 2 document clinical visits 4. Evidence of stage IV or recurrent MBC with a metastatic diagnosis date on or after 2011, as confirmed by unstructured clinical documents 4. HR+/HER2- 1. HR+: ER+ or PR+ test before or up to 60 days after MBC diagnosis 2. 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 5. 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: 1. Evidence of prior treatment with other CDK4/6I (Ribociclib or Abemaciclib), AI (Letrozole, Exemestane, and Anastrazole), Tamoxifen, Raloxifene, Toremifene, or Fulvestrant for MBC 2. First structured activity greater than 90 days after MBC diagnostic date 3. Treatment with a CDK4/6 inhibitor as part of a clinical trial
References
Publications (4)
- DERIVEDBrufsky A, Liu X, Li B, McRoy L, Layman RM. Real-World Effectiveness of Palbociclib Plus Letrozole vs Letrozole Alone for Metastatic Breast Cancer With Lung or Liver Metastases: Flatiron Database Analysis. Front Oncol. 2022 Jul 4;12:865292. doi: 10.3389/fonc.2022.865292. eCollection 2022. PMID 35860587
- DERIVEDPatt D, Liu X, Li B, McRoy L, Layman RM, Brufsky A. Real-World Treatment Patterns and Outcomes of Palbociclib Plus an Aromatase Inhibitor for Metastatic Breast Cancer: Flatiron Database Analysis. Clin Breast Cancer. 2022 Aug;22(6):601-610. doi: 10.1016/j.clbc.2022.05.002. Epub 2022 May 5. PMID 35643624
- DERIVEDBrufsky A, Liu X, Li B, McRoy L, Layman RM. Real-World Tumor Response of Palbociclib Plus Letrozole Versus Letrozole for Metastatic Breast Cancer in US Clinical Practice. Target Oncol. 2021 Sep;16(5):601-611. doi: 10.1007/s11523-021-00826-1. Epub 2021 Aug 2. PMID 34338965
- DERIVEDDeMichele A, Cristofanilli M, Brufsky A, Liu X, Mardekian J, McRoy L, Layman RM, Emir B, Torres MA, Rugo HS, Finn RS. Comparative effectiveness of first-line palbociclib plus letrozole versus letrozole alone for HR+/HER2- metastatic breast cancer in US real-world clinical practice. Breast Cancer Res. 2021 Mar 24;23(1):37. doi: 10.1186/s13058-021-01409-8. PMID 33761995