Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12606000527561
Ethics application status
Approved
Date submitted
20/03/1998
Date registered
20/03/1998
Date last updated
5/12/2011
Type of registration
Prospectively registered

Titles & IDs
Public title
ATAC - Arimidex, Tamoxifen, Alone or in Combination
Scientific title
A randomised, double-blind trial comparing Arimidex alone with Nolvadex alone with Arimidex and Nolvadex in combination, as adjuvant treatment in post-menopausal women with breast cancer.
Secondary ID [1] 15 0
National Clinical Trials Registry: NCTR219
Universal Trial Number (UTN)
Trial acronym
ATAC
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Breast Cancer 15 0
Condition category
Condition code
Cancer 15 15 0 0
Breast

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients are randomised to receive one of three treatment regimens:
* Arimidex 1mg orally daily for 5 years + Nolvadex placebo orally daily for 5 years
* Arimidex placebo orally daily for 5 years + Nolvadex 20 mg orally daily for 5 years
* Arimidex 1mg orally daily for 5 years + Nolvadex 20mg orally daily for 5 years
Intervention code [1] 1289 0
Treatment: Drugs
Comparator / control treatment
to be confirmed
Control group
Active

Outcomes
Primary outcome [1] 29 0
To compare Tamoxifen and Arimidex and to compare Tamoxifen and the combination of Arimidex plus Tamoxifen in terms of time to recurrence of breast cancer.
Timepoint [1] 29 0
The trial statistician will monitor the number of recurrences. One interim analysis will be conducted when approximately half the expected number of events (352/2=176) has occurred in any one arm.

The major trial analysis will be performed when approximately 352 disease recurrence events have occurred in any one treatment arm. This analysis occurred in quarter 4 2004.

A Data Safety Monitoring Committee has been established and reviews the safety data periodically and also considers the results from the interim and main analysis.
Primary outcome [2] 30 0
To compare Tamoxifen and Arimidex and to compare Tamoxifen and the combination of Arimidex plus Tamoxifen in terms of Safety and side effects.
Timepoint [2] 30 0
The trial statistician will monitor the number of recurrences. One interim analysis will be conducted when approximately half the expected number of events (352/2=176) has occurred in any one arm.

The major trial analysis will be performed when approximately 352 disease recurrence events have occurred in any one treatment arm. This analysis occurred in quarter 4 2004.

A Data Safety Monitoring Committee has been established and reviews the safety data periodically and also considers the results from the interim and main analysis.
Secondary outcome [1] 45 0
To compare Tamoxifen and Arimidex and to compare Tamoxifen and the combination of Arimidex plus Tamoxifen in terms of: Time to distant recurrence
Timepoint [1] 45 0
The trial statistician will monitor the number of recurrences. One interim analysis will be conducted when approximately half the expected number of events (352/2=176) has occurred in any one arm.

The major trial analysis will be performed when approximately 352 disease recurrence events have occurred in any one treatment arm.
Secondary outcome [2] 46 0
To compare Tamoxifen and Arimidex and to compare Tamoxifen and the combination of Arimidex plus Tamoxifen in terms of: Survival
Timepoint [2] 46 0
The formal statistical analysis of time to death will be undertaken when approximately 352 deaths have occurred in any one treatment arm.
Secondary outcome [3] 47 0
To compare Tamoxifen and Arimidex and to compare Tamoxifen and the combination of Arimidex plus Tamoxifen in terms of: New breast primaries
Timepoint [3] 47 0
to be confirmed

Eligibility
Key inclusion criteria
Histologically proven operable invasive breast cancer. Patients who completed all primary surgery and chemotherapy and are candidates to receive hormonal adjuvant therapy. Post-menopausal women according to one or more of the following: a) aged 60 or > b) aged 45-59 and satisfying one or more of the following: i) amenorrhea for at least 12 months and intact uterus ii) amenorrhea < 12 months and FSH within post-menopausal range; including: Patients who have had hysterectomy. Patients who received HRT. Patients rendered amenorrhoeic by adjuvant chemotherapy iii) bilateral oophorectomy.
Minimum age
18 Years
Maximum age
Not stated
Sex
Females
Can healthy volunteers participate?
No
Key exclusion criteria
Clinical evidence of metastatic disease. Patients unlikey to comply with trial requirements. Patients whose chemotherapy started > 8 weeks after completion of primary surgery or whose chemotherapy completed > 8 weeks before starting randomised treatment. Patients who have not received chemotherapy and whose primary surgery completed > 8 weeks before starting randomised treatment. Patients who received previous hormonal therapy as adjuvant treatment for breast cancer, unless: a) this was tamoxifen started prior to first surgical procedure and received < 29 days orb) this was hormonal therapy received pre-surgery in context of a formal trial, approved by Steering Committee. Patients who received tamoxifen as part of any breast cancer prevention trials, e.g. IBIS. Patients unwilling to stop taking any drug known to affect sex hormonal status, or in whom it would be inappropriate to stop. Previous history of invasive breast cancer or other invasive malignancy within last 10 years, other than squamous or basal cell carcinoma of skin or carcinoma in situ of cervix, adequately cone biopsied. Any severe concomitant disease placing patient at unusual risk or confound results of trial. Treatment with nonapproved or experimental drug 3 mths prior to randomisation. Patients at risk of transmitting any infection through blood or body fluids.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
The ANZ BCTG Operations Office provides a central randomisation service by fax for all Australian and New Zealand institutions. At the time of study entry all participants will be allocated a treatment code and study drug will be supplied in accordance with the treatment code.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated stratified blocks
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Subjects and investigators (clinicians assessing patients) are blinded to treatment.
Phase
Phase 3
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
1/04/1998
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
6000
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 17 0
Self funded/Unfunded
Name [1] 17 0
Australia and New Zealand Breast Cancer Trials Group
Country [1] 17 0
Australia
Funding source category [2] 18 0
Commercial sector/Industry
Name [2] 18 0
AstraZeneca
Country [2] 18 0
Australia
Primary sponsor type
Commercial sector/Industry
Name
AstraZeneca (formerly known as Zeneca, formerly known as ICI)
Address
Postal Address
AstraZeneca P.O. Box 131
North Ryde NSW 1670
Country
Australia
Secondary sponsor category [1] 15 0
Other Collaborative groups
Name [1] 15 0
Australia and New Zealand Breast Cancer Trials Group
Address [1] 15 0
PO Box 155
Hunter Region Mail Centre NSW 2310
Country [1] 15 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 193 0
Box Hill Hospital
Ethics committee address [1] 193 0
Ethics committee country [1] 193 0
Australia
Date submitted for ethics approval [1] 193 0
Approval date [1] 193 0
Ethics approval number [1] 193 0
Ethics committee name [2] 194 0
Liverpool Hospital
Ethics committee address [2] 194 0
Ethics committee country [2] 194 0
Australia
Date submitted for ethics approval [2] 194 0
Approval date [2] 194 0
Ethics approval number [2] 194 0
Ethics committee name [3] 195 0
Maroondah Hospital
Ethics committee address [3] 195 0
Ethics committee country [3] 195 0
Australia
Date submitted for ethics approval [3] 195 0
Approval date [3] 195 0
Ethics approval number [3] 195 0
Ethics committee name [4] 196 0
Monash Medical Centre
Ethics committee address [4] 196 0
Ethics committee country [4] 196 0
Australia
Date submitted for ethics approval [4] 196 0
Approval date [4] 196 0
Ethics approval number [4] 196 0
Ethics committee name [5] 197 0
Newcastle Mater Misericordiae Hospital
Ethics committee address [5] 197 0
Ethics committee country [5] 197 0
Australia
Date submitted for ethics approval [5] 197 0
Approval date [5] 197 0
Ethics approval number [5] 197 0
Ethics committee name [6] 198 0
Peter MacCallum Cancer Centre
Ethics committee address [6] 198 0
Ethics committee country [6] 198 0
Australia
Date submitted for ethics approval [6] 198 0
Approval date [6] 198 0
Ethics approval number [6] 198 0
Ethics committee name [7] 199 0
Prince of Wales Hospital
Ethics committee address [7] 199 0
Ethics committee country [7] 199 0
Australia
Date submitted for ethics approval [7] 199 0
Approval date [7] 199 0
Ethics approval number [7] 199 0
Ethics committee name [8] 200 0
Royal Adelaide Hospital
Ethics committee address [8] 200 0
Ethics committee country [8] 200 0
Australia
Date submitted for ethics approval [8] 200 0
Approval date [8] 200 0
Ethics approval number [8] 200 0
Ethics committee name [9] 201 0
Royal Prince Alfred Hospital
Ethics committee address [9] 201 0
Ethics committee country [9] 201 0
Australia
Date submitted for ethics approval [9] 201 0
Approval date [9] 201 0
Ethics approval number [9] 201 0
Ethics committee name [10] 202 0
St Vincent's Hospital, Melbourne
Ethics committee address [10] 202 0
Ethics committee country [10] 202 0
Australia
Date submitted for ethics approval [10] 202 0
Approval date [10] 202 0
Ethics approval number [10] 202 0
Ethics committee name [11] 203 0
Waikato Hospital
Ethics committee address [11] 203 0
Ethics committee country [11] 203 0
New Zealand
Date submitted for ethics approval [11] 203 0
Approval date [11] 203 0
Ethics approval number [11] 203 0

Summary
Brief summary
The ATAC trial is testing an alternative, new agent, to tamoxifen for women with early breast cancer. The new agent, Arimidex, is an aromatase inhibitor which acts to reduce the level of circulating oestrogen in post menopausal women. This drug seems to be well tolerated and also effective against breast cancer.

The ATAC trial is a double blind study comparing 5 years of tamoxifen, with 5 years of Arimidex, and with 5 years of tamoxifen plus Arimidex. In addition, there are three very important sub studies which investigate the effects of the treatments on bone, the endometrium and quality of life (QOL). Australia had a high rate of recruitment to the QOL sub study and is also one of the few countries contributing to the endometrial sub study.

The ATAC trial is one of the largest (over 9000 women internationally) and most rapidly completed breast cancer studies in the world. Active accrual to the main study and sub-studies was completed internationally in May 2000, and patient follow-up continues.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 36012 0
Address 36012 0
Country 36012 0
Phone 36012 0
Fax 36012 0
Email 36012 0
Contact person for public queries
Name 10478 0
Australia and New Zealand Breast Cancer Trials Group
Address 10478 0
ANZBCTG
PO Box 283
The Junction NSW 2291
Country 10478 0
Australia
Phone 10478 0
+61 2 4925 3068
Fax 10478 0
+61 2 49850141
Email 10478 0
enquiries@anzbctg.newcastle.edu.au
Contact person for scientific queries
Name 1406 0
Prof. John F. Forbes
Address 1406 0
ANZBCTG
PO Box 283
The Junction NSW 2291
Country 1406 0
Australia
Phone 1406 0
+61 2 4925 3068
Fax 1406 0
+61 2 4985 0141
Email 1406 0
enquiries@anzbctg.newcastle.edu.au

No information has been provided regarding IPD availability


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No Supporting Document Provided



Results publications and other study-related documents

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