A Study to Learn About the Study Medicine Called PF-07220060 in Combination With Fulvestrant in People With HR-positive, HER2-negative Advanced or Metastatic Breast Cancer Who Progressed After a Prior Line of Treatment

AN INTERVENTIONAL, OPEN-LABEL, RANDOMIZED, MULTICENTER PHASE 2 STUDY OF PF-07220060 PLUS FULVESTRANT COMPARED TO INVESTIGATOR'S CHOICE OF THERAPY IN PARTICIPANTS AT LEAST18 YEARS OF AGE WITH HORMONE RECEPTOR-POSITIVE, HER2-NEGATIVE ADVANCED/METASTATIC BREAST CANCER WHOSE DISEASE PROGRESSED AFTER PRIOR CDK 4/6 INHIBITOR-BASED THERAPY (FOURLIGHT-1)

Status

Active, not recruiting

Phases

Phase 3

Study type

Interventional

Source

JPRN

Registry ID

JPRN-jRCT2051230196

Enrollment

510

Registered

2024-03-11

Start date

2024-05-09

Completion date

Unknown

Last updated

2026-09-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

HR-positive, HER2-negative Advanced or Metastatic Breast Cancer

Interventions

Arm A (Experimental Arm) PF-07220060 plus Fulvestrant Arm B (Active Comparator) Fulvestrant monotherapy or Everolimus plus Exemestane

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: * Histological confirmation of breast cancer with evidence of locally advanced or metastatic disease, which is not amenable to surgical resection or radiation therapy with curative intent. * Documented estrogen receptor (ER) and/or progesterone receptor (PR)- positive tumor * Documented HER2-negative tumor * Able to provide a sufficient amount of representative formalin fixed, paraffin embedded (FFPE) tumor tissue specimen. * Must have received CDK4/6i + NSAI defined per study protocol. There must be documented PD during or after CDK4/6i treatment. * Measurable disease or non-measurable bone only disease as defined by RECIST version 1.1. * Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) 2 or less

Exclusion criteria

Exclusion criteria: * Any medical or psychiatric condition that may increase the risk of study participation or make the participant inappropriate for the study. * In visceral crisis at risk of immediately life-threatening complications in the short term. * Known active uncontrolled or symptomatic central nervous system metastases, carcinomatous meningitis, or leptomeningeal disease. * Prior treatment with any of the following: * Everolimus or investigational anti-cancer agents in any setting; Prior chemotherapy in the advanced setting; Radiation within 2 weeks of randomization * Current use or anticipated need for any prohibited food, supplements or concomitant medication(s) (ie, other anti-cancer therapies, growth factors, chronic systemic corticosteroids, strong and moderate cytochrome P450 3A4/5 [CYP3A4/5] or uridine 5' diphosphate-glucuronosyltransferase 2B7 [UGT2B7] inhibitors and inducers, direct oral anticoagulants, proton pump inhibitors). * Inadequate renal function, hepatic dysfunction, or hematologic abnormalities.

Design outcomes

Primary

Measure	Time frame
Progression-Free Survival (PFS) by blinded independent central review (BICR) per RECIST v1.1	—

Secondary

Measure	Time frame
1. Overall Survival (OS) 2. PFS by investigator 3. Objective Response (OR) by BICR and investigator 4. Duration of Response (DOR) by BICR and by investigator 5. Clinical Benefit Response (CBR) by BICR and by investigator 6. Adverse Events (AEs) including type, incidence, seriousness, relationship to study interventions 7. Abnormal Electrocardiogram (ECG) 8. Laboratory Test Abnormalities 9. Patient reported outcome (PRO) including EQ-5D-5L, EORTC QLQ and EORTC QLQ BR23 10. Ctrough of PF-07220060	—

Measure

Time frame

1. Overall Survival (OS) 2. PFS by investigator 3. Objective Response (OR) by BICR and investigator 4. Duration of Response (DOR) by BICR and by investigator 5. Clinical Benefit Response (CBR) by BICR and by investigator 6. Adverse Events (AEs) including type, incidence, seriousness, relationship to study interventions 7. Abnormal Electrocardiogram (ECG) 8. Laboratory Test Abnormalities 9. Patient reported outcome (PRO) including EQ-5D-5L, EORTC QLQ and EORTC QLQ BR23 10. Ctrough of PF-07220060

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Countries

Argentina, Australia, Brazil, Canada, China, India, Israel, Japan, Mexico, South Korea, Taiwan, Turkey (Turkiye), United Kingdom, United States

Contacts

Public ContactClinical Trials Information Desk

Pfizer R&D Japan G.K.

clinical-trials@pfizer.com+81-3-5309-7000

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Sep 19, 2026