Trial · NCT00248170

Comparison Trial of Letrozole to Anastrozole in the Adjuvant Treatment of Postmenopausal Women With Hormone Receptor and Node Positive Breast Cancer

NCT00248170, Phase 3, Completed, Novartis Pharmaceuticals; results first posted 2015-10-09

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. Comparison Trial of Letrozole to Anastrozole in the Adjuvant Treatment of Postmenopausal Women With Hormone Receptor and Node Positive Breast Cancer. Trials, record NCT00248170. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT00248170

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Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: Comparison Trial of Letrozole to Anastrozole in the Adjuvant Treatment of Postmenopausal Women With Hormone Receptor and Node Positive Breast Cancer
NCT number: NCT00248170
Status: Completed
Phases: Phase 3
Enrollment: 4,172 participants, actual
Lead sponsor: Novartis Pharmaceuticals
Conditions: Breast Cancer
Interventions: Letrozole, Anastrozole
First posted: 2005-11-03
Last updated: 2016-04-19
Other registries' IDs: eudract:2005-004263-35
Results first posted: 2015-10-09

Source ClinicalTrials.gov

Registered outcomes8

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	Disease Free Survival	84 months	Disease-free survival was defined as the time from the date of randomization to the date of the first documentation of re-occurrence of invasive breast cancer in local, regional or distant sites, new invasive breast cancer in the contra-lateral breast, or death from any cause.
Secondary	Overall Survival	84 months	Overall survival was defined as the time from the date of randomization to the date of death from any cause.
Secondary	Time to Development of Distant Metastases	84 months	Time to development of distant metastases was defined as the time from date of randomization to the date of the first development of any recurrent or metastatic disease in sites other than the local mastectomy scar, the ipsilateral breast in case of breast conservation or the contra lateral breast.
Secondary	Time to Development of Contra Lateral Breast Cancer	84 months	Time to development of contra lateral breast cancer was defined as the time from the date of randomization to the date of the first development of any disease in the contra lateral breast.
Secondary	Distant Disease-free Survival	84 months	Distant disease-free survival was defined as the time from date of randomization to the date of the first development of any relapse at a distant site or death from any cause.
Secondary	Change From Baseline in Serum Lipid Profiles	baseline, 6, 12, 24, 36, 48 and 60 months	Total cholesterol was analyzed to assess the impact on serum lipids profiles. The adjusted means was calculated.
Secondary	Percentage of Participants Who Experienced Clinical Fracture Events	84 months	The incidence of clinical fractures was analyzed.
Secondary	Percentage of Participants Who Experienced Cardiovascular Events	84 months	The incidence of ischemic heart disease, cardiac failures, cerebrovascular accidents and thromboembolic events was analyzed.

Source ClinicalTrials.gov

Outcomes8

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	Disease Free Survival	84 months	Intent-to-treat (ITT) - the ITT contained randomized participants who had no protocol deviations.	Months	MEDIAN
SECONDARY	Overall Survival	84 months	Intent-to-treat (ITT) - the ITT contained randomized participants who had no protocol deviations.	Months	MEDIAN
SECONDARY	Time to Development of Distant Metastases	84 months	Intent-to-treat (ITT) - the ITT contained randomized participants who had no protocol deviations.	Months	MEDIAN
SECONDARY	Time to Development of Contra Lateral Breast Cancer	84 months	Intent-to-treat (ITT) - the ITT contained randomized participants who had no protocol deviations.	Months	MEDIAN
SECONDARY	Distant Disease-free Survival	84 months	Intent-to-treat (ITT) - the ITT contained randomized participants who had no protocol deviations.	Months	MEDIAN
SECONDARY	Change From Baseline in Serum Lipid Profiles	baseline, 6, 12, 24, 36, 48 and 60 months	Safety Set: The safety set included randomized participants who received at least one of study medication and had at least one post baseline assessment.	mg/dL	MEAN
SECONDARY	Percentage of Participants Who Experienced Clinical Fracture Events	84 months	Safety Set: The safety set included randomized participants who received at least one of study medication and had at least one post baseline assessment.	Percentage of participants	NUMBER
SECONDARY	Percentage of Participants Who Experienced Cardiovascular Events	84 months	Safety Set: The safety set included randomized participants who received at least one of study medication and had at least one post baseline assessment.	Percentage of participants	NUMBER

Source ClinicalTrials.gov

Results by group32

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units
Disease Free Survival	Letrozole	NA	95% Confidence Interval 84.14 to NA	Months
Disease Free Survival	Anastrozole	NA	95% Confidence Interval NA to NA	Months
Overall Survival	Letrozole	NA	95% Confidence Interval NA to NA	Months
Overall Survival	Anastrozole	NA	95% Confidence Interval NA to NA	Months
Time to Development of Distant Metastases	Letrozole	NA	95% Confidence Interval 84.14 to NA	Months
Time to Development of Distant Metastases	Anastrozole	NA	95% Confidence Interval NA to NA	Months
Time to Development of Contra Lateral Breast Cancer	Letrozole	NA	95% Confidence Interval NA to NA	Months
Time to Development of Contra Lateral Breast Cancer	Anastrozole	NA	95% Confidence Interval NA to NA	Months
Distant Disease-free Survival	Letrozole	NA	95% Confidence Interval 84.14 to NA	Months
Distant Disease-free Survival	Anastrozole	NA	95% Confidence Interval NA to NA	Months

1 to 10 of 32Source ClinicalTrials.gov

See all 32 results by group

Participant flow10

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	Letrozole	2,078
Overall Study	STARTED	Anastrozole	2,094
Overall Study	Intent-to-treat (ITT)	Letrozole	2,061
Overall Study	Intent-to-treat (ITT)	Anastrozole	2,075
Overall Study	Safety Set	Letrozole	2,049
Overall Study	Safety Set	Anastrozole	2,062
Overall Study	COMPLETED	Letrozole	1,317
Overall Study	COMPLETED	Anastrozole	1,286
Overall Study	NOT COMPLETED	Letrozole	761
Overall Study	NOT COMPLETED	Anastrozole	808

Source ClinicalTrials.gov

Adverse events1,382

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk
other	Nausea	Gastrointestinal disorders	Letrozole	127	2,049
other	Nausea	Gastrointestinal disorders	Anastrozole	148	2,062
other	Fatigue	General disorders	Letrozole	345	2,049
other	Fatigue	General disorders	Anastrozole	341	2,062
other	Oedema peripheral	General disorders	Letrozole	100	2,049
other	Oedema peripheral	General disorders	Anastrozole	104	2,062
other	Radiation skin injury	Injury, poisoning and procedural complications	Letrozole	120	2,049
other	Radiation skin injury	Injury, poisoning and procedural complications	Anastrozole	88	2,062
other	Hypercholesterolaemia	Metabolism and nutrition disorders	Letrozole	155	2,049
other	Hypercholesterolaemia	Metabolism and nutrition disorders	Anastrozole	151	2,062

1 to 10 of 1,382Source ClinicalTrials.gov

See all 1,382 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Letrozole
Total, all-cause mortality	Anastrozole
Total, other adverse events	Letrozole	1,747	2,049
Total, other adverse events	Anastrozole	1,762	2,062
Total, serious adverse events	Letrozole	486	2,049
Total, serious adverse events	Anastrozole	520	2,062

Source ClinicalTrials.gov

Papers1

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as
38460476	DERIVED

Source PubMed

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons1

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison
Letrozole vs Anastrozole: serious adverse events

Source Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

GET https://conductscience.org/api/trials/v1/NCT00248170

GET https://conductscience.org/api/trials/v1/NCT00248170/results?page=2

API reference For AI assistants