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Letrozole for Breast Cancer

Phase 3
Waitlist Available
Research Sponsored by Pfizer
Eligibility Criteria Checklist
Specific guidelines that determine who can or cannot participate in a clinical trial
Must have
Be older than 18 years old
Timeline
Screening 3 weeks
Treatment Varies
Follow Up from date of randomization until death due to any cause or censored, (assessed up to data cut-off date of 15-nov-2021, approximately 8.7 years)
Awards & highlights

Summary

This trial is testing a combination of letrozole and palbociclib in postmenopausal women with a specific type of advanced breast cancer. Letrozole reduces estrogen levels, which can slow cancer growth, while palbociclib stops cancer cells from dividing. The goal is to see if this combination works better than letrozole alone.

Timeline

Screening ~ 3 weeks
Treatment ~ Varies
Follow Up ~from date of randomization until death due to any cause or censored, (assessed up to data cut-off date of 15-nov-2021, approximately 8.7 years)
This trial's timeline: 3 weeks for screening, Varies for treatment, and from date of randomization until death due to any cause or censored, (assessed up to data cut-off date of 15-nov-2021, approximately 8.7 years) for reporting.

Treatment Details

Study Objectives

Study objectives can provide a clearer picture of what you can expect from a treatment.
Primary study objectives
Progression-Free Survival (PFS) as Assessed by the Investigator.
Secondary study objectives
Change From Baseline Between Treatment Comparison in Euro Quality of Life (EQ-5D) Index
Change From Baseline Between Treatment Comparison in Functional Assessment of Cancer Therapy -Breast (FACT-B)
Corrected QT Interval (QTc) Time-matched Change From Baseline on Cycle 1 Day 14
+11 more

Trial Design

2Treatment groups
Experimental Treatment
Active Control
Group I: PD-0332991 + LetrozoleExperimental Treatment2 Interventions
PD-0332991, 125mg, orally once daily on Day 1 to Day 21 of every 28-day cycle followed by 7 days off treatment in combination with Letrozole, 2.5mg, orally once daily (continuously).
Group II: Placebo + LetrozoleActive Control2 Interventions
Placebo, 125mg, orally once daily on Day 1 to Day 21 of every 28-day cycle followed by 7 days off treatment in combination with Letrozole, 2.5mg, orally once daily (continuously).
Treatment
First Studied
Drug Approval Stage
How many patients have taken this drug
Letrozole
2002
Completed Phase 4
~3590
PD-0332991
2013
Completed Phase 3
~1180

Find a Location

Who is running the clinical trial?

PfizerLead Sponsor
4,635 Previous Clinical Trials
17,736,019 Total Patients Enrolled
115 Trials studying Breast Cancer
41,409 Patients Enrolled for Breast Cancer
Pfizer CT.gov Call CenterStudy DirectorPfizer
3,525 Previous Clinical Trials
14,908,582 Total Patients Enrolled
46 Trials studying Breast Cancer
17,754 Patients Enrolled for Breast Cancer
~53 spots leftby Oct 2025