MedPath

Letrozole After Tamoxifen in Treating Women With Breast Cancer

Phase 3
Completed
Conditions
Breast Cancer
Interventions
Other: placebo
Registration Number
NCT00003140
Lead Sponsor
NCIC Clinical Trials Group
Brief Summary

RATIONALE: Estrogen can stimulate the growth of breast cancer cells. Hormone therapy using letrozole may fight breast cancer by reducing the production of estrogen.

PURPOSE: This randomized phase III trial is studying letrozole to see how well it works in treating women with breast cancer who have received tamoxifen for at least 5 years.

Detailed Description

OBJECTIVES:

Primary

* Compare the disease-free survival and overall survival of postmenopausal women with primary breast cancer who have completed at least five years of adjuvant aromatase inhibitor as initial therapy or after tamoxifen treated with letrozole or placebo.

Secondary

* Compare the incidence of contralateral breast cancer in patients treated with these regimens.

* Evaluate the long-term clinical and laboratory safety of letrozole, in terms of lipid profile, cardiovascular morbidity and mortality, incidence of bone fractures, change in bone density, and common toxic effects, in this patient population.

* Compare the quality of life of patients treated with these regimens. Re-randomization

Primary

* Compare disease-free survival of patients who, after receiving at least 4.5 years of letrozole, are re-randomized to receive an additional 5 years of letrozole vs placebo.

Secondary

* Determine whether common genetic polymorphisms for genes encoding proteins involved in pharmacokinetic and/or pharmacodynamic pathways for letrozole contribute to individual variation in toxicity and efficacy of letrozole therapy.

OUTLINE: This is a randomized, double-blind, placebo-controlled, multicenter study. Patients are stratified according to receptor status (positive vs unknown), lymph node status (negative vs positive vs unknown), prior adjuvant chemotherapy (yes vs no), interval between last dose of aromatase inhibitor therapy and randomization (\< 6 months vs 6 months-2 years), and duration of prior tamoxifen use (0 years vs \< 2 years vs 2-4.5 years vs \> 4.5 years). Patients are randomized to 1 of 2 treatment arms.

* Arm I: Patients receive oral letrozole once daily.

* Arm II: Patients receive oral placebo once daily. In both arms, treatment continues for 5 years in the absence of disease progression or unacceptable toxicity. Patients in arm II may then be offered oral letrozole once daily for up to 5 years.

Quality of life is assessed at baseline, at 6 months, and then annually for 4.5 years.

* Double-blind, re-randomization:

Patients who complete ≥ 4.5 years of letrozole (arm I) and who did not experience recurrent disease or new primary breast cancer, including ductal carcinoma in situ, may participate in the double-blind, placebo-controlled, re-randomization portion of the study. Patients are stratified according to lymph node status at enrollment (negative vs positive vs unknown), prior adjuvant chemotherapy (yes vs no), and interval between last dose of letrozole and re-randomization (\<6 months vs 6 months to 2 years). Common genetic single nucleotide polymorphisms for genes encoding proteins involved in pharmacokinetic and/or pharmacodynamic pathways for letrozole are analyzed in order to determine if these single nucleotide polymorphisms contribute to individual variation in toxicity and efficacy of letrozole therapy.

Quality of life is assessed as during the first randomization.

Patients are followed annually.

PROJECTED ACCRUAL: A total of 4,700 patients will be accrued for this study.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
5187
Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Arm IletrozolePatients receive oral letrozole once daily.
Arm IIplaceboPatients receive oral placebo once daily.
Primary Outcome Measures
NameTimeMethod
Disease-free survival5 years
Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (57)

The Moncton Hospital

🇨🇦

Moncton, New Brunswick, Canada

Allan Blair Cancer Centre

🇨🇦

Regina, Saskatchewan, Canada

St. Michael's Hospital

🇨🇦

Toronto, Ontario, Canada

Mount Sinai Hospital

🇨🇦

Toronto, Ontario, Canada

Univ. Health Network-The Toronto General Hospital

🇨🇦

Toronto, Ontario, Canada

The Vitalite Health Network - Dr. Leon Richard

🇨🇦

Moncton, New Brunswick, Canada

Saskatoon Cancer Centre

🇨🇦

Saskatoon, Saskatchewan, Canada

Peterborough Regional Health Centre

🇨🇦

Peterborough, Ontario, Canada

Thunder Bay Regional Health Science Centre

🇨🇦

Thunder Bay, Ontario, Canada

QEII Health Sciences Center

🇨🇦

Halifax, Nova Scotia, Canada

The Royal Marsden NHS Foundation Trust - Sutton

🇬🇧

Surrey, United Kingdom

Toronto East General Hospital

🇨🇦

Toronto, Ontario, Canada

The Royal Victoria Hospital

🇨🇦

Barrie, Ontario, Canada

Markham Stouffville Hospital

🇨🇦

Markham, Ontario, Canada

Humber River Regional Hospital

🇨🇦

Toronto, Ontario, Canada

Niagara Health System

🇨🇦

St. Catharines, Ontario, Canada

Regional Cancer Program of the Hopital Regional

🇨🇦

Sudbury, Ontario, Canada

BCCA - Vancouver Island Cancer Centre

🇨🇦

Victoria, British Columbia, Canada

Ottawa Health Research Institute - General Division

🇨🇦

Ottawa, Ontario, Canada

Atlantic Health Sciences Corporation

🇨🇦

Saint John, New Brunswick, Canada

North York General Hospital

🇨🇦

Toronto, Ontario, Canada

PEI Cancer Treatment Centre,Queen Elizabeth Hospital

🇨🇦

Charlottetown, Prince Edward Island, Canada

Wythenshawe Hospital

🇬🇧

Manchester, United Kingdom

London Regional Cancer Program

🇨🇦

London, Ontario, Canada

Univ. Health Network-Princess Margaret Hospital

🇨🇦

Toronto, Ontario, Canada

Odette Cancer Centre

🇨🇦

Toronto, Ontario, Canada

St. Joseph's Health Centre

🇨🇦

Toronto, Ontario, Canada

Trillium Health Centre - West Toronto

🇨🇦

Toronto, Ontario, Canada

Windsor Regional Cancer Centre

🇨🇦

Windsor, Ontario, Canada

Centre de Sante et de services sociaux de Gatineau

🇨🇦

Gatineau, Quebec, Canada

L'Hotel-Dieu de Levis

🇨🇦

Levis, Quebec, Canada

Hopital Maisonneuve-Rosemont

🇨🇦

Montreal, Quebec, Canada

McGill University - Dept. Oncology

🇨🇦

Montreal, Quebec, Canada

CHUM - Pavillon Saint-Luc

🇨🇦

Montreal, Quebec, Canada

Hopital du Sacre-Coeur de Montreal

🇨🇦

Montreal, Quebec, Canada

Centre hospitalier universitaire de Sherbrooke

🇨🇦

Sherbrooke, Quebec, Canada

CHUQ-Pavillon Hotel-Dieu de Quebec

🇨🇦

Quebec City, Quebec, Canada

CHA-Hopital Du St-Sacrement

🇨🇦

Quebec City, Quebec, Canada

University Institute of Cardiology and

🇨🇦

Quebec, Canada

CancerCare Manitoba

🇨🇦

Winnipeg, Manitoba, Canada

NRGH - Nanaimo Cancer Clinic

🇨🇦

Nanaimo, British Columbia, Canada

BCCA - Fraser Valley Cancer Centre

🇨🇦

Surrey, British Columbia, Canada

Lethbridge Cancer Centre

🇨🇦

Lethbridge, Alberta, Canada

Dr. H. Bliss Murphy Cancer Centre

🇨🇦

St. John's, Newfoundland and Labrador, Canada

Juravinski Cancer Centre at Hamilton Health Sciences

🇨🇦

Hamilton, Ontario, Canada

Cancer Centre of Southeastern Ontario at Kingston

🇨🇦

Kingston, Ontario, Canada

Algoma District Cancer Program

🇨🇦

Sault Ste. Marie, Ontario, Canada

Credit Valley Hospital

🇨🇦

Mississauga, Ontario, Canada

Stronach Regional Health Centre at Southlake

🇨🇦

Newmarket, Ontario, Canada

Lakeridge Health Oshawa

🇨🇦

Oshawa, Ontario, Canada

CHUM - Hotel Dieu du Montreal

🇨🇦

Montreal, Quebec, Canada

CHUM - Hopital Notre-Dame

🇨🇦

Montreal, Quebec, Canada

The Royal Marsden NHS Foundation Trust

🇬🇧

London, United Kingdom

Christie's Hospital NHS Trust

🇬🇧

Manchester, United Kingdom

Penticton Regional Hospital

🇨🇦

Penticton, British Columbia, Canada

BCCA - Vancouver Cancer Centre

🇨🇦

Vancouver, British Columbia, Canada

BCCA - Cancer Centre for the Southern Interior

🇨🇦

Kelowna, British Columbia, Canada

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