A Study Of Oral Palbociclib (PD-0332991), A CDK4/6 Inhibitor, As Single Agent In Japanese Patients With Advanced Solid Tumors Or In Combination With Letrozole For The First-Line Treatment Of Postmenopausal Japanese Patients With ER (+) HER2 (-) Advanced Breast Cancer
CompletedPhase 2Results postedLast updated 23 November 2020
What this trial tests
Phase 2 trial testing PD-0332991 in Neoplasms in 61 participants. Completed in 25 October 2018.
20 and older, any sex, with Neoplasms or Breast Neoplasms. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Number of Participants With Dose Limiting Toxicities (DLT): Part 1 Phase 1Primary· Lead-in period (Day -7) up to Day 28 (Cycle 1)
DLT was classified as per common terminology criteria for adverse events (CTCAE) version 4.0 as any of the events occurring during 28 days of Cycle 1,attributed to study drug:grade 4 neutropenia(for a duration of greater than \[\>\]7 days); febrile neutropenia (grade greater than or equal to \[\>=\]3 neutropenia,body temperature \>=38.5 degree Celsius);grade \>=3 thrombocytopenia with bleeding episode;grade 4 thrombocytopenia;grade \>=3 non-hematologic toxicity except grade 3 or more nausea, vomiting,electrolyte abnormality(if controllable by therapy);grade 3 QTc prolongation(\>500 millisecond
Group
Value
95% CI
PD-0332991 100 mg: Dose Escalation Cohort
1
PD-0332991 125 mg: Dose Escalation Cohort
1
Number of Participants With Treatment-Related Adverse Events (AEs) and Serious Adverse Events (SAEs): Part 2 Phase 1Primary· Baseline (Day 1) up to 28 days after last dose of study drug (up to 1673 days)
A treatment related AE is any untoward medical occurrence in a clinical investigation participant administered a product or medical device; the event had a causal relationship with the treatment or usage. A SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.
Relatedness was judged by investigator. AEs included both serious and non-serious adverse events.
AEs
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
6
SAEs
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
2
Number of Participants With Treatment-Emergent Adverse Events (TEAEs) By Severity: Part 2 Phase 1Primary· Baseline (Day 1) up to 28 days after last dose of study drug (up to 1673 days)
AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. An AE was considered treatment emergent if occurred for the first time after the start of study treatment or occurred prior to the start of treatment but increased in National Cancer Institute (NCI) CTCAE grade during study treatment period. AE severity was defined to be the maximum toxicity grade of the TEAEs experienced by the participants during the study. AE was assessed according to severity as: Grade 1 (mild AE), Grade 2 (moderate AE), Grade 3 (severe AE),
Grade 1
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
0
Grade 2
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
0
Grade 3
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
4
Grade 4
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
2
Grade 5
Group
Value
95% CI
PD-0332991 125 mg+ Letrozole 2.5 mg: MTD Cohort
0
Percentage of Participants With 1 Year Progression Free Survival (PFS): Phase 2Primary· From initiation of treatment up to 12 months
PFS was defined as the time from first dose of study treatment 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 was defined using Response Evaluation Criteria In Solid Tumors Criteria (RECIST v1.1), as a 20% increase in the sum of the longest diameter of target lesions, or a measurable increase in a non-target lesion, or the appearance of new lesions.1-year PFS was defined as the percentage of participants without PFS events (PD or death due to any cause) at 12 months based on
Number of Participants With Treatment-Related Adverse Events (AEs) and Serious Adverse Events (SAEs): Phase 1 (Part 1) and Phase 2Secondary· Part 1 Phase 1: Lead-in period (Day -7) up to 28 days after last dose of study drug (up to 308 days), Phase 2: Baseline (Day 1) up to 28 days after last dose of study drug (up to 1526 days)
A treatment related AE is any untoward medical occurrence in a clinical investigation participant administered a product or medical device; the event had a causal relationship with the treatment or usage. A SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly.
Relatedness was judged by investigator. AEs included both serious and non-serious adverse events.
Number of Participants With Treatment-Emergent Adverse Events (AEs) By Severity: Phase 1 (Part 1) and Phase 2Secondary· Part 1 Phase 1: Lead-in period (Day -7) up to 28 days after last dose of study drug (up to 308 days), Phase 2: Baseline (Day 1) up to 28 days after last dose of study drug (up to 1526 days)
AE was any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. An AE was considered treatment emergent if occurred for the first time after the start of study treatment or occurred prior to the start of treatment but increased in NCI CTCAE version 4.0 grade during study treatment period. AE severity was defined to be the maximum toxicity grade of the TEAEs experienced by the participants during the study. AE was assessed according to severity as: Grade 1 (mild AE), Grade 2 (moderate AE), Grade 3 (severe AE), Grade 4 (life-t
Number of Participants With Clinically Significant Laboratory AbnormalitiesSecondary· Part 1 Phase 1: Lead-in period (Day -7) up to 308 days; Part 2 Phase 1: Baseline (Day 1) up to 1673 days; Phase 2: Baseline (Day 1) up to 1526 days
Abnormality criteria: hemoglobin: \<0.8\*lower limit of normal \[LLN\], platelets: \<0.5\*LLN or \>1.75\*upper limit of normal \[ULN\], leukocytes: \<0.6\*LLN or \>1.5\*ULN, lymphocytes, total neutrophils: \<0.8\*LLN or \>1.2\*ULN, basophils, eosinophil,monocytes: \>1.2\*ULN); aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, gamma glutamyl transferase (GT): \>0.3\*ULN, total protein, albumin: \<0.8\*LLN or \>1.2\*ULN, total bilirubin, direct bilirubin: \>1.5\*ULN; blood urea nitrogen, creatinine: \>1.3\*ULN, uric acid: \>1.2\*ULN; sodium: \<0.95\*LLN or \>1.05\*ULN,
Area Under the Plasma Concentration Time Curve Over Dosing Interval (AUCtau) of PD-0332991 Following Multiple Dose: Part 1 Phase 1Secondary· Multiple dose: 0 hour (pre-dose), 1, 2, 4, 6, 8, 12, 24 hours post-dose on Cycle 1 Day 8
AUCtau is area under the plasma concentration-time curve over dosing interval which is calculated by log-linear trapezoidal method.
Group
Value
95% CI
PD-0332991 100 mg: Dose Escalation Cohort
1276
± 45
PD-0332991 125 mg: Dose Escalation Cohort
2838
± 43
AUCtau Dose Normalized to 125 Milligram (mg) of PD-0332991 Following Multiple Dose: Part 1 Phase 1Secondary· Multiple dose: 0 hour (pre-dose), 1, 2, 4, 6, 8, 12, 24 hours post-dose on Cycle 1 Day 8
AUCtau Dose Normalized to 125 mg is area under the plasma concentration-time curve over dosing interval dose normalized to 125 mg which is calculated by log-linear trapezoidal method.
Group
Value
95% CI
PD-0332991 100 mg: Dose Escalation Cohort
1595
± 45
PD-0332991 125 mg: Dose Escalation Cohort
2838
± 43
Area Under the Plasma Concentration-Time Curve From 0 to Time 24 Hours (AUC24) of PD-0332991 Following Single Dose: Part 1 Phase 1Secondary· Single dose: 0 hour (pre-dose), 1, 2, 4, 6, 8, 12 and 24 hours post-dose in Lead-in period (Day -7)
AUC24 is area under the plasma concentration-time curve from 0 to time 24 hours which is calculated by log-linear trapezoidal method.
Group
Value
95% CI
PD-0332991 100 mg: Dose Escalation Cohort
547.5
± 19
PD-0332991 125 mg: Dose Escalation Cohort
1322
± 42
AUC24 Dose Normalized to 125 mg of PD-0332991 Following Single Dose: Part 1 Phase 1Secondary· Single dose: 0 hour (pre-dose), 1, 2, 4, 6, 8, 12 and 24 hours post-dose in Lead-in period (Day -7)
AUC24 Dose Normalized to 125 mg is area under the plasma concentration-time curve from 0 to time 24 hours dose normalized to 125 mg which is calculated by log-linear trapezoidal method.
Group
Value
95% CI
PD-0332991 100 mg: Dose Escalation Cohort
684.5
± 19
PD-0332991 125 mg: Dose Escalation Cohort
1322
± 42
Area Under the Plasma Concentration-Time Curve From Time Zero to Infinity (AUCinf) of PD-0332991 Following Single Dose: Part 1 Phase 1Secondary· Single dose: 0 hour (pre-dose), 1, 2, 4, 6, 8, 12, 24, 48, 72, 96, 120 hours post-dose in Lead-in period (Day -7)
AUCinf is area under the plasma concentration-time curve from 0 to infinity which is calculated by log-linear trapezoidal method.
Group
Value
95% CI
PD-0332991 100 mg: Dose Escalation Cohort
1039
± 32
PD-0332991 125 mg: Dose Escalation Cohort
2483
± 49
Adverse events — posted to ClinicalTrials.gov
Time frame: Part 1 Phase 1: Lead-in period (Day -7) up to 28 days after last dose of study drug (up to 308 days), Part 2 Phase 1: Baseline (Day 1) up to 28 days after last dose of study drug (up to 1673 days), Phase 2: Baseline (Day 1) up to 28 days after last dose of study drug (up to 1526 days).
Reporting threshold: 5%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
This study is comprised of two portions: a Phase 1 portion and a Phase 2 portion. The Phase 1 portion is a single-country, non-randomized, open label, clinical trial which will evaluate the safety, tolerability, preliminary efficacy, and PK profile of PD-0332991 as a single agent in Japanese patients with advanced solid tumors, and PD-0332991 in combination with letrozole in the first-line treatment of Japanese patients with ER(+) HER2(-) ABC. The Phase 2 portion is a single-country, non-randomized, open-label, single-cohort, multi-center clinical trial to evaluate the efficacy and safety of PD-0332991 in combination with letrozole for the first-line treatment of postmenopausal Japanese patients with ER(+) HER2(-) ABC.
Publications & conference data
8 peer-reviewed publications reference this trial (live from Europe PMC):
NCT01740427 — A Study of Palbociclib (PD-0332991) + Letrozole vs. Letrozole For 1st Line Treatment Of Postmenopausal Women With ER+/HE
· Phase 3
· completed
NCT01356628 — A Clinical Research Study to Determine Whether PD 0332991 May Be Effective in Treating Patients With Liver Cancer
· Phase 2
· completed
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Publications: Europe PMC API search by NCT ID, retrieved 10 June 2026
Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
Sponsor: as reported to ClinicalTrials.gov by Pfizer
Last refreshed: 23 November 2020
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT01684215.