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Active, not recruiting Phase 1Phase 2 Interventional

TACTIVE-U: A Study to Learn About the Study Medicine (Vepdegestrant) When Given With Other Medicines in People With Advanced or Metastatic Breast Cancer (Sub-Study B)

ClinicalTrials.gov ID: NCT05573555

Public ClinicalTrials.gov record NCT05573555. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced May 16, 2026, 6:01 AM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

TACTIVE-U: AN INTERVENTIONAL SAFETY AND EFFICACY PHASE 1B/2, OPEN-LABEL UMBRELLA STUDY TO INVESTIGATE TOLERABILITY, PK, AND ANTITUMOR ACTIVITY OF VEPDEGESTRANT (ARV-471/PF-07850327), AN ORAL PROTEOLYSIS TARGETING CHIMERA, IN COMBINATION WITH OTHER ANTICANCER TREATMENTS IN PARTICIPANTS AGED 18 YEARS AND OVER WITH ER+ ADVANCED OR METASTATIC BREAST CANCER, SUB-STUDY B (ARV-471 IN COMBINATION WITH RIBOCICLIB)

Study identification

NCT ID
NCT05573555
Recruitment status
Active, not recruiting
Study type
Interventional
Phase
Phase 1, Phase 2
Lead sponsor
Pfizer
Industry
Enrollment
20 participants

Conditions and interventions

Conditions

Interventions

  • ARV-471 Drug
  • Ribociclib Drug

Drug

Eligibility (public fields only)

Age range
18 Years and older
Sex
All
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Feb 28, 2023
Primary completion
Dec 29, 2026
Completion
Dec 29, 2026
Last update posted
Mar 8, 2026

2023 – 2026

United States locations

U.S. sites
20
U.S. states
5
U.S. cities
10
Facility City State ZIP Site status
Stanford Women's Cancer Center Palo Alto California 94304
UCSF Medical Center at Mission Bay San Francisco California 94158
Moffitt Cancer Center - International Plaza Tampa Florida 33607
Moffitt Cancer Center, Richard M. Shulze Family Foundation Outpatient Center Tampa Florida 33612
Moffitt Cancer Center Tampa Florida 33612
Moffitt McKinley Hospital Tampa Florida 33612
Siteman Cancer Center - WUPI Shiloh Illinois 62269
Brigham and Women's Hospital Boston Massachusetts 02115
Dana-Farber Cancer Institute Boston Massachusetts 02215
Dana-Farber Cancer Institute - Chestnut Hill Newton Massachusetts 02459
Siteman Cancer Center - St Peters City of Saint Peters Missouri 63376
Siteman Cancer Center - West County Creve Coeur Missouri 63141
Siteman Cancer Center - North County Florissant Missouri 63031
Siteman Cancer Center St Louis Missouri 63108
Barnes Jewish Hospital Department of Laboratories St Louis Missouri 63110
Barnes-Jewish Hospital St Louis Missouri 63110
Washington University School of Medicine - Siteman Cancer Center St Louis Missouri 63110
Washington University School of Medicine St Louis Missouri 63110
Barnes Jewish Hospital Lab- South County St Louis Missouri 63129
Siteman Cancer Center - South County St Louis Missouri 63129

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

Non-U.S. locations

This page focuses on the U.S. directory. The official record also lists 9 non-U.S. sites.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT05573555, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Mar 8, 2026 · Synced May 16, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT05573555 live on ClinicalTrials.gov.

View official ClinicalTrials.gov record →