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 A)

NCT ID: NCT05548127

Last Updated: 2025-09-09

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

ACTIVE_NOT_RECRUITING

Clinical Phase

PHASE1/PHASE2

Total Enrollment

37 participants

Study Classification

INTERVENTIONAL

Study Start Date

2023-02-23

Study Completion Date

2026-03-01

Brief Summary

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The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called ARV-471) when given together with other medicines for the potential treatment of advanced or metastatic breast cancer.

This study is seeking participants who have breast cancer that:

* is advanced, may have spread to other organs (metastatic) and cannot be fully treated by surgery or radiation therapy
* is sensitive to hormonal therapy (it is called estrogen receptor positive); and
* is no longer responding to previous treatments This study is divided into separate sub-studies.

For Sub-Study A:

All participants will receive ARV-471 and a medicine called abemaciclib. ARV-471 will be given by mouth, at home, 1 time a day. Abemaciclib will be given by mouth, at home, 2 times a day. We will examine the experiences of people receiving the study medicines. This will help us determine if the study medicines are safe and effective.

Participants will continue to take ARV-471 and abemaciclib until their cancer is no longer responding, or side effects become too severe. They will have visits at the study clinic about every 4 weeks.

Detailed Description

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C4891006 is a sub-study from the Umbrella platform, TACTIVE-U, comprising multiple sub-studies that independently evaluate ARV-471 in participants with Estrogen Receptor Positive (ER+) Advanced or Metastatic Breast Cancer (A/MBC). ARV-471 will act as the backbone therapy given in combination with other anticancer agents thought to have clinical relevance in ER+ breast cancer.

Conditions

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Breast Cancer

Study Design

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Allocation Method

NA

Intervention Model

SEQUENTIAL

Phase 1b will use an escalation/de-escalation approach to determine the RP2D of ARV-471 when administered in combination with abemaciclib. The decision to de-escalate the starting dose levels of ARV 471 will be using mTPI-2 decision criteria based on the number of DLT-evaluable participants and the number of DLTs in those participants during the DLT observation period (Cycle 1 \[first 28 days\]).

Phase 2 will further evaluate the preliminary antitumor activity and safety of the combination RP2D.
Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

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ARV-471 in combination with Abemaciclib

ARV-471 administered orally once daily (QD) and Abemaciclib orally twice daily (BID) on 28-day cycle

Group Type EXPERIMENTAL

ARV-471

Intervention Type DRUG

Daily oral dosages of ARV-471 continuously, dose escalation/de-escalation in Phase 1b until the recommended phase 2 dose (RP2D) determined, cycles lasting 28 days

Abemaciclib

Intervention Type DRUG

Daily oral dosages of Abemaciclib continuously, cycles lasting 28 days

Interventions

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ARV-471

Daily oral dosages of ARV-471 continuously, dose escalation/de-escalation in Phase 1b until the recommended phase 2 dose (RP2D) determined, cycles lasting 28 days

Intervention Type DRUG

Abemaciclib

Daily oral dosages of Abemaciclib continuously, cycles lasting 28 days

Intervention Type DRUG

Other Intervention Names

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vepdegestrant, PF-07850327

Eligibility Criteria

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Inclusion Criteria

* histological or cytological diagnosis of ER+ and HER2- advanced/metastatic breast cancer that is not amendable to surgical resection with curative intent (≥1% ER+ stained cells on the most recent tumor biopsy).
* prior anticancer therapies: at least 1 and no more than 2 lines of prior therapies for advanced/metastatic disease; 1 line of any CDK4/6 inhibitor-based regimen is required (independent of the setting eg, adjuvant or advanced/metastatic)
* at least 1 measurable lesion as defined by RECIST v1.1.
* ECOG PS ≤1.

Exclusion Criteria

* visceral crisis at risk of life-threatening complications in the short term
* known history of drug-induced pneumonitis or other significant symptomatic deterioration of lung functions.
* newly diagnosed brain metastases, or symptomatic CNS metastases, carcinomatous meningitis, or leptomeningeal disease. Participants with a history of CNS metastases or cord compression are eligible if they have been definitively treated, clinically stable and discontinued anti-seizure medications and corticosteroids for at least 14 days prior to enrollment in the study.
* history of any other tumor malignancies within the past 3 years, except for the following: (1) adequately treated basal or squamous cell carcinoma of the skin; (2) curatively treated in situ carcinoma of the cervix.
* inflammatory breast cancer
* impaired cardiovascular function or clinically significant cardiovascular diseases
* concurrent administration of medications, food, or herb supplements that are strong inhibitors and strong/moderate inducers of CYP3A and drugs known to predispose to Torsade de Pointes or QT interval prolongation.
* renal impairment, not adequate liver function and/or bone marrow function
* known active infection
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

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Arvinas Estrogen Receptor, Inc.

INDUSTRY

Sponsor Role collaborator

Pfizer

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Principal Investigators

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Pfizer CT.gov Call Center

Role: STUDY_DIRECTOR

Pfizer

Locations

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Stanford Women's Cancer Center

Palo Alto, California, United States

Site Status

UCSF Medical Center at Mission Bay

San Francisco, California, United States

Site Status

Moffitt Cancer Center - International Plaza

Tampa, Florida, United States

Site Status

Moffitt Cancer Center, Richard M. Shulze Family Foundation Outpatient Center

Tampa, Florida, United States

Site Status

Moffitt McKinley Hospital

Tampa, Florida, United States

Site Status

Siteman Cancer Center - WUPI

Shiloh, Illinois, United States

Site Status

Siteman Cancer Center - St Peters

City of Saint Peters, Missouri, United States

Site Status

Siteman Cancer Center - West County

Creve Coeur, Missouri, United States

Site Status

Siteman Cancer Center - North County

Florissant, Missouri, United States

Site Status

Barnes-Jewish Hospital

St Louis, Missouri, United States

Site Status

Washington University School of Medicine - Siteman Cancer Center

St Louis, Missouri, United States

Site Status

Washington University School of Medicine

St Louis, Missouri, United States

Site Status

Siteman Cancer Center - South County

St Louis, Missouri, United States

Site Status

U.T. MD Anderson Cancer Center, Investigational Pharmacy Services - Unit 376

Houston, Texas, United States

Site Status

U.T. MD Anderson Cancer Center

Houston, Texas, United States

Site Status

University of Texas MD Anderson Cancer Center

Houston, Texas, United States

Site Status

Northwest Medical Specialties, PLLC

Bonney Lake, Washington, United States

Site Status

Northwest Medical Specialties, PLLC

Federal Way, Washington, United States

Site Status

Northwest Medical Specialties, PLLC

Gig Harbor, Washington, United States

Site Status

Northwest Medical Specialties, PLLC

Puyallup, Washington, United States

Site Status

Northwest Medical Specialties, PLLC

Tacoma, Washington, United States

Site Status

BC Cancer Vancouver

Vancouver, British Columbia, Canada

Site Status

BC Cancer Vancouver

Vancouver, British Columbia, Canada

Site Status

The Ottawa Hospital - General Campus

Ottawa, Ontario, Canada

Site Status

Sunnybrook Research Institute

Toronto, Ontario, Canada

Site Status

CIUSSS- saguenay-Lac-Saint-Jean

Chicoutimi, Quebec, Canada

Site Status

Jewish General Hospital

Montreal, Quebec, Canada

Site Status

Fondazione Policlinico Universitario Agostino Gemelli IRCCS - Università Cattolica del Sacro Cuore

Rome, Lazio, Italy

Site Status

Istituto di Candiolo IRCCS - Fondazione del Piemonte per l'Oncologia

Candiolo, Torino, Italy

Site Status

Hospital Universitari Vall d'Hebron

Barcelona, Barcelona [barcelona], Spain

Site Status

Hospital Universitari Dexeus

Barcelona, Catalunya [cataluña], Spain

Site Status

Clinica Universidad de Navarra

Madrid, Madrid, Comunidad de, Spain

Site Status

Clínica Universidad de Navarra

Madrid, Madrid, Comunidad de, Spain

Site Status

Hospital Universitario 12 de Octubre

Madrid, Madrid, Comunidad de, Spain

Site Status

Clinica Universidad de Navarra

Pamplona, Navarre, Spain

Site Status

Hospital Universitario Virgen Del Rocio

Seville, , Spain

Site Status

Countries

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United States Canada Italy Spain

Related Links

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https://pmiform.com/clinical-trial-info-request?StudyID=C4891006

To obtain contact information for a study center near you, click here.

Other Identifiers

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2022-502228-34-00

Identifier Type: REGISTRY

Identifier Source: secondary_id

C4891006

Identifier Type: -

Identifier Source: org_study_id

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