Condition category
Cancer
Date applied
24/02/2006
Date assigned
01/06/2006
Last edited
28/07/2015
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

http://www.cptu.org.uk/trials/IBISI.php

Contact information

Type

Scientific

Primary contact

Prof Jack Cuzick

ORCID ID

Contact details

Department of Epidemiology
Wolfson Institute of Preventive Medicine
Charterhouse House Square
London
EC1M 6BQ
United Kingdom
+44 (0)207 014 0226
jack.cuzick@cancer.org.uk

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

N/A

Study information

Scientific title

An international multicentre study of tamoxifen versus placebo in women at increased risk of breast cancer

Acronym

IBIS-I

Study hypothesis

A study to evaluate the reduction in incidence of, and mortality from, breast cancer associated with taking tamoxifen daily for five years.

Ethics approval

The start of the IBIS I study predated the existence of Multicentre Research Ethics Committees (MREC). However, Central Office for Research Ethics Committees (COREC) have appointed the Central and South Bristol Research Ethics Committee to be the lead REC for the IBIS I study. The Central South Bristol REC reference assigned to study is E3244.

Study design

A multicentre, randomised clinical trial of 7,000 women aged between 45 and 70 years who have a risk of breast cancer at least twice that of the general population

Primary study design

Interventional

Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type

Prevention

Patient information sheet

Patient information can be found at: http://www.ibis-trials.org/ibis1/infoleafp1.html

Condition

Breast cancer chemoprevention

Intervention

Women were randomised to receive either tamoxifen 20 mg per day for 5 years or placebo

Intervention type

Drug

Phase

Not Applicable

Drug names

Tamoxifen

Primary outcome measures

The development of histologically confirmed breast cancer, both invasive and non-invasive (i.e. including ductal carcinoma in situ [DCIS].

Secondary outcome measures

Other cancers, other serious medical conditions or side effects.

Overall trial start date

14/04/1992

Overall trial end date

30/03/2011

Reason abandoned

Eligibility

Participant inclusion criteria

To be eligible, women must satisfy at least one of the entry criteria listed below:
1. A mammogram must have been taken within the last year indicating no malignant disease
2. A signed consent form must have been obtained

Entry criteria:
The entry criteria was based on a relative risk of at least two-fold for women aged 45-70 years, four-fold for women aged 40-44 years and ten-fold for women aged 35-39 years.

Age 45-70 years:
1. First degree relative who developed breast cancer at age 50 or less
2. First degree relative who developed bilateral breast cancer
3. Two or more first or second degree relatives who developed breast cancer
4. Nulliparous and a first degree relative who developed breast cancer
5. Benign biopsy with proliferative disease and a first degree relative who developed breast cancer
6. Lobular carcinoma in situ
7. Atypical ductal or lobular hyperplasia in a benign lesion
8. Women at high risk who do not fit into the above categories (risk equivalent)*
* These women must have clearly apparent family history indicating at least two fold increased risk of breast cancer.

Age 40-44 years
8. Two or more first or second degree relatives who developed breast cancer at age 50 or less
9. First degree relative with bilateral breast cancer who developed the first breast cancer at age 50 or less
10. Nulliparous and a first degree relative who developed breast cancer at age 40 or less
11. Benign biopsy with proliferative disease and a first degree relative who developed breast cancer at age 40 or less
12. Lobular carcinoma in situ
13. Atypical ductal or lobular hyperplasia in a benign lesion
14. Women at high risk who do not fit into the above categories (risk equivalent)*
* These women must have clearly apparent family history indicating at least four fold increased risk of breast cancer.

Age 35-39 years:
15. Two or more first degree relatives who developed breast cancer at age 50 or less
16. First degree relative with bilateral breast cancer who developed the first breast cancer at age 40 or less
17. Lobular carcinoma in situ
18. Women at high risk who do not fit into the above categories (risk equivalent)*
* These women must have clearly apparent family history indicating at least ten fold increased risk of breast cancer.

Participant type

Patient

Age group

Adult

Gender

Female

Target number of participants

7,000

Participant exclusion criteria

1. Pregnant, or at pregnancy risk. If necessary, pre and peri menopausal women must use non-hormonal contraception during the trial
2. Any previous cancer (except non-melanoma skin cancer or in situ cancer of the cervix)
3. Life expectancy of less than 10 years or other medical condition more serious than the risk of breast cancer
4. Psychologically and physically unsuitable for five years tamoxifen or placebo therapy
5. Current treatment with anti-coagulants
6. Previous deep vein thrombosis or pulmonary embolus
7. Current tamoxifen use

Recruitment start date

14/04/1992

Recruitment end date

30/03/2011

Locations

Countries of recruitment

Australia, Belgium, Finland, Switzerland, United Kingdom

Trial participating centre

Wolfson Institute of Preventive Medicine
London
EC1M 6BQ
United Kingdom

Sponsor information

Organisation

Queen Mary University of London (UK)

Sponsor details

Research and Development
Third Floor Rutland House
42-46 New Road
London
E1 2AX
United Kingdom
+44 (0)207 882 7250
gerry.leonard@bartsandthelondon.nhs.uk

Sponsor type

University/education

Website

http://www.bartsandthelondon.org.uk/research

Funders

Funder type

Charity

Funder name

Imperial Cancer Reserach Fund, Cancer Research Campaign, Cancer Research UK

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

2002 results in: http://www.ncbi.nlm.nih.gov/pubmed/12243915
2013 substudy results in: http://www.ncbi.nlm.nih.gov/pubmed/22832202
2014 extended long-term follow-up results in: http://www.ncbi.nlm.nih.gov/pubmed/25497694
2014 placebo arm results in: http://www.ncbi.nlm.nih.gov/pubmed/25292294

Publication citations

  1. Results

    Cuzick J, Forbes J, Edwards R, Baum M, Cawthorn S, Coates A, Hamed A, Howell A, Powles T, , First results from the International Breast Cancer Intervention Study (IBIS-I): a randomised prevention trial., Lancet, 2002, 360, 9336, 817-824.

  2. Substudy results

    Palva T, Ranta H, Koivisto AM, Pylkkänen L, Cuzick J, Holli K, A double-blind placebo-controlled study to evaluate endometrial safety and gynaecological symptoms in women treated for up to 5 years with tamoxifen or placebo - a substudy for IBIS I Breast Cancer Prevention Trial., Eur. J. Cancer, 2013, 49, 1, 45-51, doi: 10.1016/j.ejca.2012.06.015.

  3. Results

    Cuzick J, Sestak I, Cawthorn S, Hamed H, Holli K, Howell A, Forbes JF; on behalf of the IBIS-I Investigators, Tamoxifen for prevention of breast cancer: extended long-term follow-up of the IBIS-I breast cancer prevention trial, Lancet Oncol, 2014, doi: 10.1016/S1470-2045(14)71171-4.

  4. Results

    Warwick J, Birke H, Stone J, Warren RM, Pinney E, Brentnall AR, Duffy SW, Howell A, Cuzick J, Mammographic breast density refines Tyrer-Cuzick estimates of breast cancer risk in high-risk women: findings from the placebo arm of the International Breast Cancer Intervention Study I, Breast Cancer Res, 2014, 16, 5, 451, doi: 10.1186/s13058-014-0451-5.

Additional files

Editorial Notes