Recent Updates
Recently added Catalysts

PD-0332991

Phase 3

Breast Neoplasms | Small molecule | Oncology |Pfizer, Inc.|Last Updated: May 14, 2026

Success Probability
Approval Probability 71%
TA Base Rate26%
Adjusted LOA41%
ML RiskLOW_RISK
Premium
Market & Valuation
rNPV $3.2B
Market Size $9.4B
Revenue Basis $1.6B
Competitors 6
Premium
Trial Design
RandomizedDouble-BlindACTIVE_CONTROLLEDDMCBiomarker
Total Trials2
Total Enrollment1,006
FDA Designations
No designations recorded
Clinical Trials (2)
NCT IDTitlePhaseStatusEnrollmentVelocityDesignStartCompletionLast UpdatedSitesCountries
NCT02297438A Study Of Palbociclib (PD-0332991) + Letrozole VS. Placebo+ Letrozole For 1st Line Treatment Of Asian Postmenopausal Women With ER+/HER2- Advanced Breast Cancer [PALOMA-4]PHASE3 COMPLETED 340Mar 23, 2015Feb 24, 2025May 14, 202654 China, Hong Kong +3
NCT01740427A Study of Palbociclib (PD-0332991) + Letrozole vs. Letrozole For 1st Line Treatment Of Postmenopausal Women With ER+/HER2- Advanced Breast Cancer (PALOMA-2)PHASE3 COMPLETED 666Feb 22, 2013Nov 9, 2023Nov 14, 2024305 United States, Australia +16
Unlock Drug Trial Details
Study Endpoints
Primary Endpoints
Progression-Free Survival (PFS) Based on Investigator's Assessment: Up to Primary Completion Date
Randomization up to 65 months

PFS was based on Kaplan-Meier estimates. PFS was defined as the time from the date of randomization to the date of the first documentation of objective progression of disease (PD) or death due to any cause in the absence of documented PD, whichever occurred first. PD is defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) as a 20% increase in the sum of diameters of target measurable lesions above the smallest sum observed (over baseline if no decrease in the sum is observed during therapy), with a minimum absolute increase of 5 mm. In this outcome measure, PFS was based on investigator's assessment.

Progression-Free Survival (PFS) as Assessed by the Investigator
From randomization date to date of first documentation of progression or death (up to approximately 2.5 years)

PFS is defined as the time from the date of randomization to the date of the first documentation of objective tumor progression as per Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1) or death due to any cause in the absence of documented PD, whichever occurs first. If tumor progression data include more than 1 date, the first date will be used. PFS (in months) will be calculated as (first event date - randomization date +1)/30.4. Progression is defined using RECIST v1.1, as a 20% increase in the sum of diameters of target measurable lesions above the smallest sum observed (over baseline if no decrease in the sum is observed during therapy), with a minimum absolute increase of 5 mm, or unequivocal progression of pre-existing non-target lesions, or the appearance of new lesions.

Secondary Endpoints
Progression-Free Survival (PFS) Based on Blinded Independent Central Review (BICR): Up to Primary Completion Date
Randomization up to 65 months
Percentage of Participants With Objective Response (OR) Based on Investigator Assessment: Up to Primary Completion Date
Randomization up to 65 months
Percentage of Participants With Objective Response (OR) Based on Investigator Assessment (Participants With Measurable Disease at Baseline): Up to Primary Completion Date
Randomization up to 65 months
Unlock Study Endpoints
Study Design & Arms
AllocationRANDOMIZED
MaskingQUADRUPLE
ModelPARALLEL
PurposeTREATMENT
Treatment Arms
ArmTypeDescription
Palbociclib + LetrozoleEXPERIMENTALPalbociclib, 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)
Placebo + LetrozoleACTIVE_COMPARATORPlacebo, 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).
PD-0332991 + LetrozoleEXPERIMENTALPD-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).
Interventions
NameTypeDescription
PalbociclibDRUGPalbociclib, 125mg, orally once daily on Day 1 to Day 21 of every 28-day cycle followed by 7 days off treatment
LetrozoleDRUGLetrozole, 2.5mg, orally once daily (continuously)
PlaceboDRUGPlacebo, 125mg, orally once daily on Day 1 to Day 21 of every 28-day cycle followed by 7 days off treatment
PD-0332991DRUGPD-0332991, 125mg, orally once daily on Day 1 to Day 21 of every 28-day cycle followed by 7 days off treatment
Unlock Study Design Details
Eligibility Criteria
Age Range18 Years — 70 Years
SexFEMALE
Healthy VolunteersNo
Study Sites54

Inclusion Criteria: * Adult Asian women with locoregionally recurrent or metastatic disease not amenable to curative therapy * Confirmed diagnosis of ER positive breast cancer * No prior systemic anti-cancer therapy for advanced ER+ disease * Postmenopausal women * Measurable disease as per Respons...

Countries:ChinaHong KongSingaporeTaiwanThailandUnited StatesAustraliaBelgiumCanadaCzechiaFranceGermanyHungaryIrelandItalyJapanPolandRussiaSouth KoreaSpainUkraineUnited Kingdom
Unlock Eligibility Criteria