# Vepdegestrant (ARV-471/PF-07850327) + Palbociclib vs Letrozole + Palbociclib in ER(+)/HER2(-) Advanced Breast Cancer

> **NCT05909397** · PHASE3 · ACTIVE_NOT_RECRUITING · sponsor: **Pfizer** · enrollment: 59 (actual)

## Conditions studied

- Breast Cancer

## Interventions

- **DRUG:** Vepdegestrant (ARV-471/PF-07850327)
- **COMBINATION_PRODUCT:** Palbociclib
- **DRUG:** Letrozole
- **COMBINATION_PRODUCT:** Palbociclib

## Key facts

- **NCT ID:** NCT05909397
- **Lead sponsor:** Pfizer
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** ACTIVE_NOT_RECRUITING
- **Start date:** 2023-08-09
- **Primary completion:** 2026-12-30
- **Final completion:** 2026-12-30
- **Target enrollment:** 59 (ACTUAL)
- **Last updated:** 2026-02-10

## Collaborators

- [object Object]

## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT05909397

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT05909397, "Vepdegestrant (ARV-471/PF-07850327) + Palbociclib vs Letrozole + Palbociclib in ER(+)/HER2(-) Advanced Breast Cancer". Retrieved via AI Analytics 2026-07-20 from https://api.ai-analytics.org/clinical/NCT05909397. Licensed CC0.

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