# 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)

> **NCT05573555** · PHASE1,PHASE2 · ACTIVE_NOT_RECRUITING · sponsor: **Pfizer** · enrollment: 20 (actual)

## Conditions studied

- Breast Cancer

## Interventions

- **DRUG:** ARV-471
- **DRUG:** Ribociclib

## Key facts

- **NCT ID:** NCT05573555
- **Lead sponsor:** Pfizer
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE1,PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** ACTIVE_NOT_RECRUITING
- **Start date:** 2023-03-01
- **Primary completion:** 2026-12-30
- **Final completion:** 2026-12-30
- **Target enrollment:** 20 (ACTUAL)
- **Last updated:** 2026-03-09

## Collaborators

- [object Object]

## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT05573555

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT05573555, "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)". Retrieved via AI Analytics 2026-06-24 from https://api.ai-analytics.org/clinical/NCT05573555. Licensed CC0.

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*[Clinical trials dataset](/datasets/clinical-trials) · CC0 1.0*