# 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)

Source: https://onco.cc/trials/nct05573555/  
OnCo record `nct05573555` (Trial). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

A phase 1/2 trial of Vepdegestrant and Ribociclib in advanced solid tumours, run by Pfizer, active and no longer recruiting.

## Summary

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) is a phase 1/2 interventional study registered as NCT05573555 by Pfizer, with 20 participants enrolled, started 2023-03-01 and due to reach its primary completion in 2026-12-30. Interventions recorded: ARV-471 and Ribociclib.

## Fields

- Kind: Trial
- Status: active
- Last checked: 2026-09-16
- Tags: pipeline; ctgov-ingest
- Registry id: NCT05573555
- Phase: 1/2
- Setting: 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)
- Sponsor: Pfizer
- Enrolled: 20

## Sources

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

## Connected records

- cancers: [Metastatic cancer (cancer that has spread)](https://onco.cc/cancers/metastatic-cancer/)
- drugs: [Ribociclib](https://onco.cc/drugs/ribociclib/), [Vepdegestrant](https://onco.cc/drugs/vepdegestrant/)
- companies: [Pfizer (incl. Seagen)](https://onco.cc/companies/pfizer/)

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JSON: https://onco.cc/api/v1/entities/nct05573555.json