# Palbociclib and Letrozole or Fulvestrant in Treating Patients With Estrogen Receptor Positive, HER2 Negative Metastatic Breast Cancer

> **NCT03633331** · PHASE2 · COMPLETED · sponsor: **Alliance for Clinical Trials in Oncology** · enrollment: 93 (actual)

## Conditions studied

- Estrogen Receptor-positive Breast Cancer
- HER2/Neu Negative
- Stage IV Breast Cancer AJCC v6 and v7

## Interventions

- **DRUG:** Palbociclib
- **DRUG:** Letrozole
- **DRUG:** Fulvestrant
- **OTHER:** Questionnaire Administration
- **OTHER:** Quality-of-Life Assessment

## Key facts

- **NCT ID:** NCT03633331
- **Lead sponsor:** Alliance for Clinical Trials in Oncology
- **Sponsor class:** OTHER
- **Phase:** PHASE2
- **Study type:** INTERVENTIONAL
- **Status:** COMPLETED
- **Start date:** 2018-08-15
- **Primary completion:** 2020-09-08
- **Final completion:** 2026-02-27
- **Target enrollment:** 93 (ACTUAL)
- **Last updated:** 2026-04-29

## Collaborators

- [object Object]

## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT03633331

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT03633331, "Palbociclib and Letrozole or Fulvestrant in Treating Patients With Estrogen Receptor Positive, HER2 Negative Metastatic Breast Cancer". Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/clinical/NCT03633331. Licensed CC0.

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