Hormone Receptor Positive Breast CancerPhase 3FALCONNCT01602380
A Global Study to Compare the Effects of Fulvestrant and Arimidex in a Subset of Patients With Breast Cancer.
A Phase 3 study testing faslodex 500mg, arimidex 1mg and faslodex dummy in people with Hormone Receptor Positive Breast Cancer, run by AstraZeneca at 118 sites in 20 countries.
Trial summary
The purpose of the study is to compare how treatment with Fulvestrant (FASLODEX) or Anastrozole (ARIMIDEX) effects disease progression for women with locally advanced or metastatic breast cancer who have not had prior hormonal treatment. Read more about this study
- Who is it for?
- Ages 18 to 130 years, women only
- Conditions the study is for
- Hormone Receptor Positive Breast Cancer
- What is being tested?
- faslodex 500mg, arimidex 1mg and faslodex dummy
- Type of treatment
- Pill or oral medicine, Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 462 participants
- Where
- 118 sitesin 20 countries
- Study dates
- 17 Oct 2012to 16 Jan 2026
- Phase
- Phase 3
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 130 years
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Histological confirmation of breast cancer in post menopausal women (age >=60). Positive hormone receptor status (ER +ve and/or PgR +ve) of primary or metastatic tumour tissue based on local laboratory assessment.
- EITHER locally advanced disease (1 line of chemotherapy allowed only if remain unsuitable for therapy of curative intent) OR Metastatic disease. (1 line of chemotherapy for breast cancer allowed only if subsequent evidence of further progressive disease)
- At least 1 lesion (measurable and/or non-measurable) that can be accurately assessed at baseline and is suitable for repeated assessment.
- Postmenopausal women, fulfilling 1 of:
- Prior bilateral oophorectomy
- Age >60 years
- Age < 60 years and amenorrheic for 12+months in the absence of chemotherapy, tamoxifen, toremifene, or ovarian suppression and FSH and oestradiol in the postmenopausal range
Who cannot join
- Presence of life-threatening metastatic disease
- Any of:
- Extensive hepatic involvement
- involving brain or meninges
- symptomatic pulmonary lymph spread
- Discrete lung metastases are acceptable if respiratory function is not significantly compromised
Show all 9Show fewer
- Prior systemic therapy for breast cancer other than one line of cytotoxic chemotherapy (the last dose of chemotherapy must have been received more than 28 days prior to randomisation)
- Radiation therapy if not completed within 28 days prior to randomisation (with the exception of radiotherapy given for control of bone pain, started prior to randomisation). Prior hormonal treatment for breast cancer.
- Current or prior malignancy within previous 3 years (other than breast cancer or adequately treated basal cell or squamous cell carcinoma of the skin or in situ carcinoma of the cervix).
Trial locations and contacts
118 sites in 20 countries.
118 sites in 20 countries
United States12 sites
Research Site
Auburn, Maine, 04212
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Columbus, Ohio, 43202
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Detroit, Michigan, 48202
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Lincoln, Nebraska, 68506
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Memphis, Tennessee, 38120
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Modesto, California, 95355
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Montgomery, Ohio, 45242
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Salt Lake City, Utah, 84107
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Savannah, Georgia, 31405
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Somerset, New Jersey, 08873
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St Louis, Missouri, 63110
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Worcester, Massachusetts, 01608
Italy10 sites
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Avellino, 83100
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Bari, 70124
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Benevento, 82100
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Catania, 95126
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Genova, 16128
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Pisa, 56100
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Roma, 00100
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Roma, 00144
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Roma, 00161
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Treviglio, 24047
Japan10 sites
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Fukuoka, 811-1395
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Hamamatsu, 430-0906
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Kagoshima, 892-0833
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Kumamoto, 860-8556
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Matsuyama, 791-0280
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Mitaka-shi, 181-8611
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Nishinomiya-shi, 663-8501
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Osaka, 540-0006
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Sakaishi, 590-0064
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Suita-shi, 565-0871
Spain10 sites
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Madrid, 28034
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Madrid, 28050
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Pamplona, 31008
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Pozuelo de Alarcón, 28223
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Sabadell, 8208
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Seville, 41009
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Seville, 41013
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Seville, 41014
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Valencia, 46014
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Valencia, 46026
Ukraine10 sites
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Cherkasy, 18009
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Dnipro, 49102
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Donetsk, 83092
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Ivano-Frankivsk, 76014
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Kharkiv Region, 61070
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Kyiv, 3115
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Lviv, 79031
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Mariupol, 87500
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Uzhhorod, 88000
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Vinnytsia, 21029
Russia9 sites
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Barnaul, 656052
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Moscow, 115478
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Omsk, 644013
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Ryazan, 390046
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Saint Petersburg, 191014
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Saint Petersburg, 195271
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Saint Petersburg, 197022
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Saint Petersburg, 197758
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Tomsk, 634028
China8 sites
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Chengdu, 610041
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Dalian, 116011
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Fuzhou, 350025
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Guangzhou, 510060
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Shanghai, 200032
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Shenyang, 110001
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Suzhou, 215004
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Tianjin, 300060
Canada6 sites
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Abbotsford British Columbia, British Columbia, V2S0C2
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Kitchener, Ontario, N2G 1G3
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Montreal, Quebec, H3T 1E2
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Montreal, Quebec, H4A 3J1
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Thunder Bay, Ontario, P7B 6V4
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Vancouver, British Columbia, V5Z 4E6
South Africa6 sites
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Cape Town, 7570
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Cape Town, 7700
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Cape Town, 7925
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Pietermaritzburg, 3201
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Pretoria, 0001
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Pretoria, 0081
Mexico5 sites
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Mérida, 97000
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Mexico City, 6760
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Monterrey, 64000
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Monterrey, 64060
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Monterrey, 64710
Argentina4 sites
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La Rioja, 5300
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Mar del Plata, B7600CTO
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Pergamino, B2700CPM
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Rosario, S2000KZE
Peru4 sites
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Lima, Lima 18
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Lima, LIMA 27
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Lima, LIMA 33
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Lima, LIMA 41
Romania4 sites
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Brăila, 810325
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Craiova, 200347
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Onești, 601048
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Timișoara, 300239
Slovakia4 sites
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Bardejov, 085 01
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Bratislava, 814 65
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Bratislava, 833 10
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Trenčín, 91171
Taiwan4 sites
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Taichung, 40447
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Taipei, 10449
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Taipei, 112
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Taipei, 235
Poland3 sites
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Katowice, 40-635
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Lodz, 90-242
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Lublin, 20-718
United Kingdom3 sites
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Airdrie, ML6 0JS
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Derby, DE22 3NE
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Stoke-on-Trent, ST4 6QG
Brazil2 sites
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Porto Alegre, 91350-200
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Santo André, 09060-870
Turkey (Türkiye)2 sites
Research Site
Ankara, 06100
Research Site
Gaziantep, 27310
About this study
Official title: A Randomised, Double-blind, Parallel-group, Multicentre, Phase III Study to Compare the Efficacy and Tolerability of Fulvestrant (FASLODEX) 500 mg With Anastrozole (ARIMIDEX) 1 mg as Hormonal Treatment for Postmenopausal Women With Hormone Receptor-Positive Locally Advanced or Metastatic Breast Cancer Who Have Not Previously Been Treated With Any Hormonal Therapy.
The purpose of the study is to compare how treatment with Fulvestrant (FASLODEX) or Anastrozole (ARIMIDEX) effects disease progression for women with locally advanced or metastatic breast cancer who have not had prior hormonal treatment.
Read the detailed description
A Randomised, Double-blind, Parallel-group, Multicentre, Phase III Study to Compare the Efficacy and Tolerability of Fulvestrant (FASLODEX) 500 mg with Anastrozole (ARIMIDEX) 1 mg as Hormonal Treatment for Postmenopausal Women with Hormone Receptor-Positive Locally Advanced or Metastatic Breast Cancer Who Have Not Previously Been Treated With Any Hormonal Therapy.
- Conditions
- Hormone Receptor Positive Breast Cancer
- Being tested
- faslodex 500mg, arimidex 1mg, faslodex dummy, arimidex dummy
- Keywords
- hormone receptor positive breast cancer, endocrine, no hormone therapy, hormone, breast, cancer, neoplasm, metastatic, tumour
- Medical subject headings
- Neoplasms, Neoplasm Metastasis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
faslodex 500mgDrug
2 x intramuscular injections at day 1, 14, 28 and every 28 days thereafter
arimidex 1mgDrug
oral tablet 1 daily
faslodex dummyDrug
2 x intramuscular injections at day 1, 14, 28 and every 28 days thereafter
arimidex dummyDrug
oral tablet 1 daily
| Study group | Role | What they receive |
|---|---|---|
| faslodex+placebo | Experimental | Blinded: Fulvestrant 500mg intramuscular injection (2x250mg) plus dummy Anastrozole tablets Receives: Drug: faslodex 500mg; Drug: arimidex dummy |
| arimidex +placebo | Active comparator | Blinded: Anastrozole 1mg tablets plus dummy Fulvestrant intramuscular injection (2x0mg) Receives: Drug: arimidex 1mg; Drug: faslodex dummy |
What is being measured
The primary outcome is the main question the study is designed to answer.
Comparison of Progression-Free Survival (PFS) in Patients Treated With Fulvestrant With Those Treated With Anastrozole
PFS was defined as the time from randomisation until objective disease progression according to Response Evaluation Criteria in Solid Tumours version 1.1 (RECIST 1.1), surgery or radiotherapy to manage worsening of disease or death by any cause (in the absence of progression). Outcome measure is reported as median time from randomisation to PFS, calculated using the Kaplan-Meier technique.
Measured: Baseline RECIST 1.1 assessments (Day 0) and then every 12 weeks until the earliest of disease progression evident, patient dies or has surgery/radiotherapy for their disease (up to approximately 38 months)
Secondary outcomes (8)
Comparison of Overall Survival (OS) in Patients Treated With Fulvestrant With Those Treated With Anastrozole; Percentage of Patients With Events
OS was defined as the time from randomisation until death by any cause. The current OS data correspond to that of the final analysis and the outcome measure is reported as percentage of patients with events.
Measured: Baseline (Day 0) up to data cut-off for final analysis (up to approximately 116 months). Following disease progression, patients were to be contacted at 12 weekly intervals to determine survival status
Objective Response Rate (ORR) for Fulvestrant Treatment Versus Anastrozole Treatment
ORR was defined as the percentage patients with an objective response (i.e. those recording a partial response [PR] or complete response [CR]) at some point during the study, prior to disease progression. ORR was assessed in patients with measurable disease at baseline only. The determination of measurable disease at baseline was done using baseline RECIST data. CR was disappearance of all target lesions since baseline; was any pathological lymph nodes selected as target lesions (TL) to have a reduction in short axis to <10 millimeter. PR was at least a 30% decrease in the sum of the diameters of TL, taking as reference the baseline sum of diameters.
Measured: Baseline RECIST 1.1 assessments (Day 0) and then every 12 weeks until disease progression or treatment discontinuation (up to approximately 38 months)
Duration of Response (DoR) for Fulvestrant Treatment Versus Anastrozole Treatment
DoR was defined only for patients who had an objective response, as the time in days from date of first documentation of response (CR/PR) until date of disease progression. CR was disappearance of all target lesions since baseline; any pathological lymph nodes selected as TL to have a reduction in short axis to <10 mm. At least a 30% decrease in the sum of the diameters of TL, taking as reference the baseline sum of diameters.
Measured: Baseline RECIST 1.1 assessments (Day 0) and then every 12 weeks until disease progression or treatment discontinuation (up to approximately 38 months)
Expected Duration of Response (EDoR) for Fulvestrant Treatment Versus Anastrozole Treatment
EDoR was estimated using the formula EDoR = p Efp(x), where x = DoR, p = proportion of responders, and Efp(x) = mean duration of response for responders. The estimation was completed by using the maximum likelihood estimates of p and Efp(x), as described by Ellis (Ellis S et al. Analysis of duration of response in oncology trials, Contemp Clin Trials 2008; 29:456-65).
Measured: Baseline RECIST 1.1 assessments and then every 12 weeks until disease progression or treatment discontinuation (up to approximately 38 months)
Clinical Benefit Rate (CBR) for Fulvestrant Treatment Versus Anastrozole Treatment
CBR was defined as the percentage of patients who had a clinical benefit (i.e. best objective response of CR, PR or stable disease), that was maintained for at least 24 weeks, prior to any evidence of progression. Note that a minimum duration of 22 weeks for CBR was applicable in the analysis (rather than 24 weeks) to allow for the protocolled window of +/-2 weeks.
Measured: Baseline RECIST 1.1 assessments (Day 0) and then every 12 weeks until disease progression or treatment discontinuation (up to approximately 38 months)
Duration of Clinical Benefit (DoCB) for Fulvestrant Treatment Versus Anastrozole Treatment
DoCB was defined only for patients who had clinical benefit, as the time in days from date of randomisation until the date of disease progression.
Measured: Baseline RECIST 1.1 assessments (Day 0) and then every 12 weeks until disease progression or treatment discontinuation (up to approximately 38 months)
Expected Duration of Clinical Benefit (EDoCB) for Fulvestrant Treatment Versus Anastrozole Treatment
EDoCB was estimated using the formula EDoCB = p Efp(x), where x = EDoCB, p = proportion of responders, and Efp(x) = mean duration of response for responders. The estimation was completed by using the maximum likelihood estimates of p and Efp(x), as described by Ellis (Ellis S et al. Analysis of duration of response in oncology trials, Contemp Clin Trials 2008; 29:456-65).
Measured: Baseline RECIST 1.1 assessments (Day 0) and then every 12 weeks until disease progression or treatment discontinuation (up to approximately 38 months)
Comparison of the Effect of Fulvestrant Treatment Versus Anastrozole Treatment on Time to Deterioration of Health-Related Quality of Life (HRQoL)
The Functional Assessment of Cancer Therapy - Breast (FACT-B) questionnaire was the instrument selected to assess HRQoL and comprised of following subscales: physical well-being (PWB), functional well-being (FWB), social well-being, emotional well-being, and breast cancer subscale (BCS). The main outcome measure from the FACT-B questionnaire was the Trial Outcome Index (TOI), which was a summary of the following subscales: PWB, FWB, and BCS. Outcome measure is reported as median time to deterioration, defined as the interval from the date of baseline of final analysis to the first assessment of worsened without an improvement in the next 12 weeks in FACT-B TOI, or the date of death (by any cause in the absence of symptom deterioration). Time to deterioration as measured by FACT-B total score was derived similarly and is also reported.
Measured: Quality of life questionnaires administered at 3 months post objective disease progression, then at 6-monthly intervals (approximately 75 months)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 May 2012 (estimated)
- Study start17 Oct 2012
- Primary completion11 Apr 2016
- Study completion16 Jan 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (4)Papers the sponsor has linked to this study.
- Other trials for Hormone Receptor Positive Breast CancerStudies of the same condition, open and under way.
- More trials run by AstraZenecaThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 462 participants (actual)
Sponsor and investigators
- Lead sponsor
- AstraZeneca
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Shankar S, MD, Study director, AstraZenecaJohn Robertson, MD, Principal investigator, Graduate Medicine and Health School, University of Nottingham, UKMatthew Ellis, DM, Principal investigator, Washington University School of Medicine, USA
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01602380
- Sponsor's protocol ID
- D699BC00001
- Other IDs
- 2011-006326-24
- Acronym
- FALCON
- Status last verified
- Feb 2026
- First submitted
- 11 May 2012
- Last updated
- 27 Feb 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Individual data sharing
- Yes: Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal. All request will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.
Publications
Robertson JFR, Shao Z, Noguchi S, Bondarenko I, Panasci L, Singh S, Subramaniam S, Ellis MJ. Fulvestrant Versus Anastrozole in Endocrine Therapy-Naive Women With Hormone Receptor-Positive Advanced Breast Cancer: Final Overall Survival in the Phase III FALCON Trial. J Clin Oncol. 2025 May;43(13):1539-1545. doi: 10.1200/JCO.24.00994. Epub 2025 Jan 7.
PubMed 39772884Robertson JFR, Cheung KL, Noguchi S, Shao Z, Degboe A, Lichfield J, Thirlwell J, Fazal M, Ellis MJ. Health-related quality of life from the FALCON phase III randomised trial of fulvestrant 500 mg versus anastrozole for hormone receptor-positive advanced breast cancer. Eur J Cancer. 2018 May;94:206-215. doi: 10.1016/j.ejca.2018.02.026. Epub 2018 Mar 22.
PubMed 29574365Robertson JFR, Bondarenko IM, Trishkina E, Dvorkin M, Panasci L, Manikhas A, Shparyk Y, Cardona-Huerta S, Cheung KL, Philco-Salas MJ, Ruiz-Borrego M, Shao Z, Noguchi S, Rowbottom J, Stuart M, Grinsted LM, Fazal M, Ellis MJ. Fulvestrant 500 mg versus anastrozole 1 mg for hormone receptor-positive advanced breast cancer (FALCON): an international, randomised, double-blind, phase 3 trial. Lancet. 2016 Dec 17;388(10063):2997-3005. doi: 10.1016/S0140-6736(16)32389-3. Epub 2016 Nov 29.
PubMed 27908454Ellis MJ, Llombart-Cussac A, Feltl D, Dewar JA, Jasiowka M, Hewson N, Rukazenkov Y, Robertson JF. Fulvestrant 500 mg Versus Anastrozole 1 mg for the First-Line Treatment of Advanced Breast Cancer: Overall Survival Analysis From the Phase II FIRST Study. J Clin Oncol. 2015 Nov 10;33(32):3781-7. doi: 10.1200/JCO.2015.61.5831. Epub 2015 Sep 14.
PubMed 26371134