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)

Running, not enrolling · Phase 1/Phase 2

Conditions studied: Breast Cancer

In brief

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.

Key facts

Study ID: NCT05548127
Run by: Pfizer
People needed: 37
Starts: 2023-02-23
Expected to finish: 2026-09-01
Last updated by the study team: 2026-02-10

Who can join

Age: 18 and older. Sex: any. Healthy volunteers: not accepted.

You may qualify if…

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.

You may not qualify if…

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

Where it is running

Stanford Women's Cancer Center — Palo Alto, California, United States
UCSF Medical Center at Mission Bay — San Francisco, California, United States
Moffitt Cancer Center - International Plaza — Tampa, Florida, United States
Moffitt Cancer Center, Richard M. Shulze Family Foundation Outpatient Center — Tampa, Florida, United States
Moffitt McKinley Hospital — Tampa, Florida, United States
Memorial Hospital — Shiloh, Illinois, United States
Siteman Cancer Center - Shiloh — Shiloh, Illinois, United States
Siteman Cancer Center - WUPI — Shiloh, Illinois, United States
Siteman Cancer Center - St Peters — City of Saint Peters, Missouri, United States
Siteman Cancer Center - West County — Creve Coeur, Missouri, United States
Siteman Cancer Center - North County — Florissant, Missouri, United States
Siteman Cancer Center — St Louis, Missouri, United States
Barnes-Jewish Hospital — St Louis, Missouri, United States
Washington University School of Medicine - Siteman Cancer Center — St Louis, Missouri, United States
Washington University School of Medicine — St Louis, Missouri, United States
Siteman Cancer Center - South County — St Louis, Missouri, United States
U.T. MD Anderson Cancer Center, Investigational Pharmacy Services - Unit 376 — Houston, Texas, United States
U.T. MD Anderson Cancer Center — Houston, Texas, United States
University of Texas MD Anderson Cancer Center — Houston, Texas, United States
Northwest Medical Specialties, PLLC — Bonney Lake, Washington, United States
Northwest Medical Specialties, PLLC — Federal Way, Washington, United States
Northwest Medical Specialties, PLLC — Gig Harbor, Washington, United States
Northwest Medical Specialties, PLLC — Puyallup, Washington, United States
Northwest Medical Specialties, PLLC — Tacoma, Washington, United States
BC Cancer Vancouver — Vancouver, British Columbia, Canada

Full record on ClinicalTrials.gov

Trial information comes from ClinicalTrials.gov and is refreshed daily. TrialsForMe does not provide medical care and does not run the studies it lists.