A retrospective study of de-identified (to preserve patient privacy) patient information from the Flatiron Health Analytic Database to compare effectiveness (i.e., overall survival) of first line palbociclib + aromatase inhibitor (AI) versus AI alone treatment in postmenopausal women or men with hormone receptor positive/human epidermal growth factor receptor 2 negative (HR+/HER2-) metastatic breast cancer (MBC) in the United States clinical practices.
Study Type
OBSERVATIONAL
Enrollment
2,888
Palbociclib + an aromatase inhibitor therapy
Aromatase inhibitor therapy
10017
New York, New York, United States
Overall Survival (OS) in Postmenopausal Female or Male Participants With Metastatic Breast Cancer
OS was defined as the time from the index date (start of palbociclib + AI or AI alone) to death. Participants who did not die, were censored at the end of study date (30-Sep-2020). Kaplan-Meier method adjusted by stabilized inverse probability of treatment weighting (sIPTW) was used.
Time frame: From index date to death due to any cause or censoring date of 30-Sep-2020 (approximately up to 68 months)
Real-World Progression Free Survival (rwPFS) in Postmenopausal Female or in Male Participants With Metastatic Breast Cancer
Real-world PFS was defined as the number of months from start of palbociclib + AI or AI alone to death from any cause or disease progression (based on clinical assessment or by radiographic scan/tissue biopsy), whichever occurred first. Disease progression was defined as at least a 20 percentage (%) increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that was the smallest on study). Participants who did not die and did not have disease progression were censored at the date of initiation of next line of therapy for participants with 2 or more lines of therapy or at the date of their last visit during the study period (February 2015-September 2020) for participants with only 1 line of therapy. Kaplan-Meier method adjusted by stabilized IPTW was used.
Time frame: From index date until disease progression or death due to any cause or censoring date (approximately up to 68 months)
Number of Participants According to Real-World Tumor Responses (rwTR): Postmenopausal Female or in Male Participants With Metastatic Breast Cancer
Real-world best responses were assessed based on treating clinician's assessment of radiological evidence for change in burden of disease over course of treatment after 1 month of index treatment initiation. Responses were classified as complete response (CR), partial response (PR), stable disease (SD), progressive disease (PD), indeterminate response (IR). CR=Complete resolution of all visible disease. PR=partial reduction in size of visible disease in some or all areas without any areas of increase in visible disease. SD=no change in overall size of visible disease. PD: an increase in visible disease; also included cases where some lesions increased in size and some lesions decreased in size; included cases where clinician indicated progressive disease; IR=study data not available for evaluation of efficacy for any reason, including participants lost to follow-up or assessment not undertaken or death. Analysis was performed using sIPTW method to balance participant characteristics.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
Time frame: From 30 days after index treatment initiation until CR, PR, SD or PD (approximately 67 months)
Real-World Response Rate (rwTR) in Postmenopausal Female or in Male Participants With Metastatic Breast Cancer
Real-world tumor response rate (rwTR) was defined as the percentage of participants with a real world complete response (rwCR) or real-world partial response (rwPR). CR: complete resolution of all visible disease. PR: partial reduction in size of visible disease in some or all areas without any areas of increase in visible disease. Analysis was performed using sIPTW method to balance participant characteristics.
Time frame: From 30 days after index treatment initiation until disease progression or death due to any cause or censoring date (approximately up to 67 months)
Number of Participants According to Initial Dose of Palbociclib: Palbociclib + Aromatase Inhibitor Arm Only
Number of participants according to the initial dose of palbociclib (75 milligrams \[mg\]/day, 100mg/day, 125 mg/day or missing dose) are reported in this outcome measure.
Time frame: At index (anytime between 03-Feb-2015 to 31-Mar-2020, approximately up to 62 months)
Time to Dose Adjustment for Palbociclib- Palbociclib + Aromatase Inhibitor Arm Only
Time to dose adjustment for participants who received palbociclib 125 mg/day, 100 mg/day, or 75 mg/day as initial dose was presented in this outcome measure.
Time frame: At index (anytime between 03-Feb-2015 to 30-Sep-2020, approximately up to 68 months)
Duration of Treatment
Duration of treatment was defined as days from index prescription order date to end of treatment, start of subsequent line of therapy, or death from any cause, whichever occurred first. Kaplan-Meier method adjusted by stabilized IPTW was used.
Time frame: From start of study treatment to end of treatment, start of subsequent line of therapy, or death from any cause, whichever occurred first (up to 68 months)
Time to Next Line of Treatment
Time to next line of treatment represents the interval from commencement of one treatment to initiation of the next line of therapy. Analysis was performed using sIPTW method to balance participant characteristics among reporting groups.
Time frame: From start of study treatment to start of next line of therapy (up to 68 months)
Time to Subsequent Chemotherapy
Time to subsequent chemotherapy represents the time interval to administration of a different chemotherapeutic agent after the first course of therapy was administered. Analysis was performed using sIPTW method to balance participant characteristics among reporting groups.
Time frame: From start of study treatment to administration of different chemotherapeutic agent (up to 68 months)
Real-World Progression Free Survival 2 (rwPFS2) in Postmenopausal Female or in Male Participants With Metastatic Breast Cancer
rwPFS2 was defined as the time from the index date to the date of the first documentation of a rwPD or death due to any cause after starting second line of therapy, whichever occurs first. Disease progression was defined as at least a 20% increase in the sum of diameters of target lesions, taking as reference the smallest sum on study (this includes the baseline sum if that was the smallest on study). In addition to the relative increase of 20%, the sum must also demonstrate an absolute increase of at least 5 mm. Analysis was performed using sIPTW method to balance participant characteristics among reporting groups.
Time frame: From start of study treatment until disease progression, or death from any cause following second line of therapy, whichever occurred first (approximately up to 68 months)