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Terminated Phase 2 Interventional Results available

Intermittent Letrozole Therapy in Postmenopausal Women With Metastatic Breast Cancer

ClinicalTrials.gov ID: NCT00549822

Public ClinicalTrials.gov record NCT00549822. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 6, 2026, 7:08 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

A Phase II Clinical Trial of Intermittent Letrozole Therapy in Postmenopausal Women With CA 15-3 Positive (Carcinoma Antigen 15-3), Hormone Receptor Positive, Metastatic Breast Cancer

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

The purpose of this research study is to study the effects of using aromatase inhibitor (AI) therapy intermittently on participants with breast cancer. AIs are a class of drugs used to treat breast cancer in postmenopausal women. They work by decreasing the level of estrogen, which is believed to stimulate the growth of tumor tissue. Breast cancer that progresses despite therapy with an AI is thought to have become resistant to AI therapy. There is scientific evidence to suggest that resistant breast cancer cells learn to grow at the very low levels of estrogen present on AI therapy, and that increasing estrogen levels even slightly by stopping AI therapy may inhibit the breast cancer cells.

Study identification

NCT ID
NCT00549822
Recruitment status
Terminated
Study type
Interventional
Phase
Phase 2
Enrollment
3 participants

Conditions and interventions

Conditions

Interventions

Drug

Eligibility (public fields only)

Age range
18 Years and older
Sex
Female
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Sep 30, 2007
Primary completion
Apr 30, 2010
Completion
Aug 31, 2013
Last update posted
Mar 21, 2017

2007 – 2013

United States locations

U.S. sites
2
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
Dana-Farber Cancer Institute Boston Massachusetts 02115
Massachusetts General Hospital Boston Massachusetts 02215

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT00549822, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Mar 21, 2017 · Synced Sep 6, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT00549822 live on ClinicalTrials.gov.

View official ClinicalTrials.gov record →