A randomised double-blind trial in post-menopausal women with primary breast cancer who have received adjuvant tamoxifen for 2-3 years, comparing subsequent adjuvant exemestane treatment with further tamoxifen

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Dr RE Coleman
Scientific

Academic Unit of Clinical Oncology
Cancer Research Centre
Weston Park Hospital
Sheffield
S10 2RX
United Kingdom

Phone	+44 (0)114 271 3518
Email	R.E.Coleman@sheffield.ac.uk

Primary study design	Interventional
Study design	Randomised double-blind controlled trial
Secondary study design	Randomised controlled trial
Study type	Participant information sheet
Scientific title	A randomised double-blind trial in post-menopausal women with primary breast cancer who have received adjuvant tamoxifen for 2-3 years, comparing subsequent adjuvant exemestane treatment with further tamoxifen
Study objectives	Early improvements in disease-free survival have been noted when an aromatase inhibitor is given either instead of or sequentially after tamoxifen in postmenopausal women with oestrogen-receptor-positive early breast cancer. However, little information exists on the long-term effects of aromatase inhibitors after treatment, and whether these early improvements lead to real gains in survival.
Ethics approval(s)	Not provided at time of registration
Health condition(s) or problem(s) studied	Breast cancer
Intervention	1. Patients in the reference arm will receive an overall course of tamoxifen for 5 years (20 mg/day) 2. Patients in the investigational arm will receive 25 mg/day exemestane (after 2-3 years tamoxifen giving a total of 5 years endocrine therapy)
Intervention type	Drug
Phase	Not Applicable
Drug / device / biological / vaccine name(s)	Tamoxifen, exemestane
Primary outcome measure(s)	Disease-free survival
Key secondary outcome measure(s)	Overall survival
Completion date	31/12/2003

Participant type(s)	Patient
Age group	Adult
Sex	Female
Target sample size at registration	4724
Key inclusion criteria	1. Histologically/cytologically confirmed unilateral operable breast adenocarcinoma 2. Estrogen receptor (ER)+ or ER unknown 3. Adequate therapy for primary disease 4. Postmenopausal 5. Receiving tamoxifen and treated with tamoxifen for 2-3 years 6. Remain free from disease following treatment for primary disease
Key exclusion criteria	Not provided at time of registration
Date of first enrolment	01/01/1998
Date of final enrolment	31/12/2003

Weston Park Hospital

Sheffield
S10 2RX
United Kingdom

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
IPD sharing plan

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	results of the 2nd interim analysis of efficacy	11/03/2004		Yes	No
Results article	survival and safety results	17/02/2007		Yes	No
Results article	5-year follow-up study results	13/03/2012		Yes	No
Results article	long-term follow-up results	01/08/2017		Yes	No
Other publications	retrospective analysis	01/04/2012		Yes	No
Participant information sheet	Participant information sheet	11/11/2025	11/11/2025	No	Yes

19/10/2017: Publication reference added.