Real-world Treatment Patterns and Effectiveness of Palbociclib and AI Therapy

Completed

Conditions: Metastatic Breast Cancer

Interventions: Drug: Palbociclib + Letrozole
Drug: Letrozole
Drug: Palbociclib + an aromatase inhibitor

Registration Number: NCT04176354

Lead Sponsor: Pfizer

Brief Summary: 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.

Detailed Description: Utilizing de-identified data derived from the Flatiron Health Analytic Database, the retrospective observational study is to describe patient characteristics, treatment patterns and effectiveness of Palbociclib + AI as first-line therapy in HR+/HER2-MBC in the US real-world clinical practice setting. Patients will be evaluated retrospectively from index therapy date to death, or last visit in the database, whichever comes first. Descriptive and multivariate statistical analyses will be performed.

Recruitment & Eligibility

Status: COMPLETED

Sex: Female

Target Recruitment: 813

Inclusion Criteria

Female sex
At least 18 years old at MBC diagnosis
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
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
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

Study & Design

Study Type: OBSERVATIONAL

Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Palbociclib + Letrozole	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.
Letrozole	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.
Palbociclib + an aromatase inhibitor	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.

Primary Outcome Measures

Name	Time	Method
Real-World Progression Free Survival (rwPFS): Using Kaplan-Meier Method	From index date to death or disease progression or end of record/data availability or censored date, whichever occurred first, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	rwPFS was defined as time (in months) from index date to death or disease progression (growth or worsening in the disease concluded by the treating clinician based on radiology, laboratory evidence, pathology, or clinical assessment) or end of record or end of data availability, whichever occurred first. If participants did not die or had disease progression, they were censored at the date of initiation of next line of therapy for participants with two or more lines of therapy or their last visit date for participants with only one line of therapy. Index date was defined as the start date of the first line therapy for Palbociclib + AI. Kaplan-Meier method was used for analysis.

Secondary Outcome Measures

Name	Time	Method
Overall Survival (OS): Using Kaplan-Meier Method	From index date to death, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	OS was defined as time (in months) from index date to the date of death. Participants who did not die during the period were censored at the time of data cut-off. Index date was defined as the start date of the first line therapy for Palbociclib + AI. Kaplan-Meier method was used for analysis.
Real-World Duration of Treatment (rwDOT): Using Kaplan-Meier Method	From index treatment initiation up to end of treatment, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	rwDOT was defined as time (in months) from index treatment initiation to end of the treatment. Index date was defined as the start date of the first line therapy for Palbociclib + AI. Kaplan-Meier method was used for analysis.
Time to First Use of Chemotherapy: Using Kaplan-Meier Method	From index treatment initiation to first use of chemotherapy or death from any cause, whichever occurred first, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	The time (in months) from index treatment initiation to first use of chemotherapy or death from any cause, whichever occurred first was reported in this outcome measure. Index date was defined as the start date of the first line therapy for Palbociclib + AI. Kaplan-Meier method was used for analysis.
Response Rate	From index date to CR or PR, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	Response rate was defined as number of participants with complete response or partial response divided by the number of participants with at least one tumor assessment while on the index treatment. Index date was defined as the start date of the first line therapy for Palbociclib + AI. The result of this outcome measure was measured in terms of proportion of participants.
Number of Participants With Real World Tumour Response (rwTR)	From index date to CR/PR/PD/SD pr PD, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	rwTR was determined based on complete response (CR), partial response (PR), stable disease (SD), progressive disease(PD), indeterminate and not documented. CR was defined as complete resolution of all visible disease. PR was defined as partial reduction in size of visible disease in some or all areas without any areas of increase in visible disease. SD was defined as no change in overall size of visible disease; also included cases where some lesions increased in size and some lesions decreased in size. PD was determined based on growth or worsening in the disease concluded by the treating clinician based on radiology, laboratory evidence, pathology, or clinical assessment. Index date was defined as the start date of the first line therapy for Palbociclib + AI.
Time From Index Date to Next Line of Anti-Cancer Therapy: Using Kaplan-Meier Method	From index treatment initiation up to next line of anti-cancer therapy or death from any cause, whichever occurred first, maximum up to approximately 43 months (data was retrieved and observed during 9 months of this retrospective study)	The time (in months) from index treatment initiation to next line of anti-cancer therapy or death from any cause, whichever occurred first was reported in this outcome measure. Index date was defined as the start date of the first line therapy for Palbociclib + AI. Kaplan-Meier method was used for analysis.