ER-Positive HER2-Negative Breast CancerPhase 3SERAFA-1NCT07647328

A Phase IIIb Study to Evaluate Camizestrant Plus Ribociclib in ER-positive, HER2-negative Advanced Breast Cancer

A Phase 3 study testing Camizestrant and Ribociclib in people with ER-Positive HER2-Negative Breast Cancer, run by AstraZeneca at 89 sites in 9 countries.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts

Official record

Search all trials

Trial summary

The purpose of this study is to investigate the efficacy, safety, and tolerability of camizestrant in combination with ribociclib in patients with ER+ HER2- BC who have not received any other systemic treatment for advanced disease. Read more about this study

Who is it for?: Ages 18 to 130 years
Conditions the study is for: ER-Positive HER2-Negative Breast Cancer
What is being tested?: Camizestrant and Ribociclib
Type of treatment: Pill or oral medicine
Could I receive a placebo?: No, everyone receives an active treatment
How many people: 150 participants
Where: 89 sitesin 9 countries
Study dates: 15 Jun 2026to 28 Feb 2029
Phase: Phase 3
Are there results?: Not yet: the study is under way

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
All sexes
No healthy volunteers
Adult, Older adult

Who may be able to join

Capable of giving signed informed consent.
Female or male, must be ≥ 18 years or as per locally allowed age limit for screening.
Type of Participant and Disease Characteristics
Histologically or cytologically documented diagnosis of ER+, HER2- BC based on local laboratory results and who are not amenable to resection or radiation therapy with curative intent.
Previously untreated with any systemic anti-cancer therapy for their locoregionally recurrent or metastatic ER+ disease.
De novo Stage 4 disease, or recurrence from early CD stage breast cancer after having received standard adjuvant endocrine therapy. Note that at least 12 months must have elapsed since the patient's last dose of adjuvant AI therapy without disease progression on treatment. Note that a 2-week washout period is required after the last dose of tamoxifen prior to randomisation.

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ECOG performance status of 0 or 1.
Adequate organ and marrow function. Sex and Contraceptive/Barrier Requirements
For those female or male patients who are not abstinent (in line with their preferred and usual lifestyle choice), and intend to be heterosexually active with a partner:
Female patients must be using highly effective contraceptive measures from the time of screening until 4 weeks after discontinuation of study treatment, and must have a negative serum pregnancy test before first dose of any study treatment if they are of childbearing potential; or must have evidence of nonchild-bearing potential by fulfilling one of the following criteria at screening:
Post-menopausal, defined as women with cessation of regular menses for at least 12 consecutive months with no alternative pathological or physiological cause: (i) Age ≥ 60 years (ii) Age < 60 years with serum estradiol and FSH level within the laboratory's reference range for post-menopausal females (iii) Previous bilateral surgical oophorectomy (iv) Medically confirmed ovarian failure OR (b) Pre/peri-menopausal, ie, not meeting the criteria for being post-menopausal.
Pre-/peri-menopausal women can be enrolled if amenable to be treated with monthly LHRH agonists (goserelin or leuprorelin [also known as leuprolide]). Patients must have concomitant treatment with LHRH agonists (goserelin or leuprorelin [leuprolide]) before or on the same day as the first dose of study treatment - and must be willing to continue on it for the duration of the study.
Non sterilised male partners of a patient who is a woman of childbearing potential must use a male condom plus spermicide (condom alone in countries where spermicides are not approved) throughout this period.
Male participants who intend to be sexually active with a female partner of childbearing potential must be surgically sterile or using an acceptable method of contraception from the time of screening throughout the total duration of the programme and the drug washout period to prevent pregnancy in a partner. Male participants must not donate or bank sperm during this same time period.
Male patients can be enrolled if amenable to be treated with monthly LHRH agonists (goserelin or leuprorelin [also known as leuprolide]) unless the patients have clear orchiectomy medical history. Willingness to use 2 non-hormonal based methods of contraception throughout the study.

Who cannot join

Participants who are not clinically indicated for endocrine therapy in combination with the CDK4/6 inhibitor ribociclib.
No evidence of advanced inoperable disease, or bone only disease with sclerotic/osteoblastic bone lesions only per standard of care imaging.
Have advanced, symptomatic, visceral spread, that are at risk of life-threatening complications in the short term, and/or pulmonary lymphangitis.
Persistent treatment-induced non-haematological toxicities (CTCAE Grade > 2).
Known active infection including tuberculosis HBV and HCV.
Known to have tested positive for HIV. Participants with HIV may be enrolled if they fulfil the criteria recommended by FDA and ASCO guidelines.

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Any clinically important abnormalities in heart conduction patterns; participants with pacemakers or medically controlled atrial fibrillation are not excluded.
Ongoing symptomatic hypotension.
Pregnant or lactating women or patients not willing to use highly effective contraception as defined in the protocol.

Trial locations and contacts

89 sites in 9 countries. Contact the study team or a site near you to ask about taking part.

AstraZeneca Clinical Study Information Center contact

1-877-240-9479

information.center@astrazeneca.com

Country

City, postcode or hospital

Sites recruiting now only

89 sites in 9 countries

Spain18 sites, 18 recruiting

Research Site
Badajoz, 06080
Not yet recruiting
Research Site
Badalona, 08916
Not yet recruiting
Research Site
Barcelona, 08041
Not yet recruiting
Research Site
Burgos, 9006
Not yet recruiting
Research Site
Donostia / San Sebastian, 20014
Not yet recruiting
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Huelva, 21005
Not yet recruiting
Research Site
Jaén, 23007
Not yet recruiting
Research Site
Las Palmas de Gran Canaria, 35016
Not yet recruiting
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Majadahonda, 28222
Not yet recruiting
Research Site
Málaga, 29010
Not yet recruiting
Research Site
Murcia, 30008
Not yet recruiting
Research Site
Oviedo, 33011
Not yet recruiting
Research Site
Palma de Mallorca, 07198
Not yet recruiting
Research Site
Pontevedra, 36312
Not yet recruiting
Research Site
Pozuelo de Alarcón, 28223
Not yet recruiting
Research Site
Santander, 39008
Not yet recruiting
Research Site
Toledo, 45007
Not yet recruiting
Research Site
Zaragoza, 50009
Not yet recruiting

Other trials in Spain

South Korea16 sites, 14 recruiting

Research Site
Cheonan-si, 31151
Not yet recruiting
Research Site
Daegu, 42415
Suspended
Research Site
Goyang-si, 10408
Not yet recruiting
Research Site
Hwasun-eup, 58128
Not yet recruiting
Research Site
Incheon, 405-760
Not yet recruiting
Research Site
Seongbuk-Gu, 02841
Not yet recruiting
Research Site
Seongnam-si, 13520
Not yet recruiting
Research Site
Seongnam-si, 13620
Not yet recruiting
Research Site
Seoul, 03080
Not yet recruiting
Research Site
Seoul, 06273
Not yet recruiting
Research Site
Seoul, 06351
Not yet recruiting
Research Site
Seoul, 06591
Not yet recruiting
Research Site
Seoul, 07985
Not yet recruiting
Research Site
Seoul, 3722
Not yet recruiting
Research Site
Songpa-gu, 05505
Not yet recruiting
Research Site
Suwon, 16499
Suspended

Other trials in South Korea

France14 sites, 14 recruiting

Research Site
Angers, 49933
Not yet recruiting
Research Site
Bayonne, 64109
Not yet recruiting
Research Site
Bobigny, 93000
Not yet recruiting
Research Site
Caen, 14000
Not yet recruiting
Research Site
Chambray-lès-Tours, 37170
Not yet recruiting
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Grenoble, 38043
Not yet recruiting
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Montpellier, 34070
Not yet recruiting
Research Site
Nancy, 54100
Not yet recruiting
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Nîmes, 30029
Not yet recruiting
Research Site
Paris, 75014
Not yet recruiting
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Pierre-Bénite, 69310
Not yet recruiting
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Valenciennes, 59300
Not yet recruiting
Research Site
Vandœuvre-lès-Nancy, 54519
Not yet recruiting
Research Site
Villejuif, 94805
Not yet recruiting

Other trials in France

United States12 sites, 12 recruiting

Research Site
Duarte, California, 91010
Not yet recruiting
Research Site
Edgewood, Kentucky, 41017
Recruiting
Research Site
Evanston, Illinois, 60201
Not yet recruiting
Research Site
Fort Worth, Texas, 76104
Recruiting
Research Site
Kingwood, Texas, 77339
Recruiting
Research Site
Louisville, Kentucky, 40202
Not yet recruiting
Research Site
Marietta, Georgia, 30060
Recruiting
Research Site
Midlothian, Virginia, 23114
Not yet recruiting
Research Site
Nashville, Tennessee, 37204
Not yet recruiting
Research Site
Palo Alto, California, 94304
Not yet recruiting
Research Site
Reno, Nevada, 89502
Not yet recruiting
Research Site
Sioux Falls, South Dakota, 57105
Not yet recruiting

Other trials in United States

Germany9 sites, 9 recruiting

Research Site
Berlin, 13125
Not yet recruiting
Research Site
Düsseldorf, 40235
Not yet recruiting
Research Site
Erlangen, 91054
Not yet recruiting
Research Site
Freiburg im Breisgau, 79110
Not yet recruiting
Research Site
Mönchengladbach, 41061
Not yet recruiting
Research Site
München, 81675
Not yet recruiting
Research Site
Paderborn, 33098
Not yet recruiting
Research Site
Trier, 54290
Not yet recruiting
Research Site
Velbert, 42551
Not yet recruiting

Other trials in Germany

Poland8 sites, 7 recruiting

Research Site
Gdansk, 80-952
Not yet recruiting
Research Site
Konin, 62-500
Not yet recruiting
Research Site
Krakow, 30-688
Not yet recruiting
Research Site
Lodz, 90-302
Not yet recruiting
Research Site
Lublin, 20-090
Not yet recruiting
Research Site
Poznan, 61-485
Not yet recruiting
Research Site
Przemyśl, 37-700
Suspended
Research Site
Wroclaw, 53-413
Not yet recruiting

Other trials in Poland

Italy5 sites, 5 recruiting

Research Site
Aviano, 33081
Not yet recruiting
Research Site
Bergamo, 24127
Not yet recruiting
Research Site
Genova, 16132
Not yet recruiting
Research Site
Milan, 20127
Not yet recruiting
Research Site
Naples, 80131
Not yet recruiting

Other trials in Italy

United Arab Emirates4 sites, 4 recruiting

Research Site
Abu Dhabi, 11241
Not yet recruiting
Research Site
Al Ain City, 00000
Not yet recruiting
Research Site
Dubai, 505004
Not yet recruiting
Research Site
Mohammed Bin Zayed City, 92510
Not yet recruiting

Other trials in United Arab Emirates

Switzerland3 sites, 3 recruiting

Research Site
Basel, 4031
Not yet recruiting
Research Site
Liestal, CH-4410
Not yet recruiting
Research Site
Rennaz, 1847
Not yet recruiting

Other trials in Switzerland

About this study

Official title: SERAFA-1: A Single Arm, Open Label, Multicentre, Phase IIIb Study Of Camizestrant Plus Ribociclib in 1st Line Treatment of ER Positive, HER2-negative Advanced Breast Cancer Patients

Read the detailed description

This global, multicenter, Phase IIIb, single-arm study will evaluate the efficacy, safety, and tolerability of camizestrant combined with ribociclib in patients with ER+ HER2- advanced breast cancer who have not previously received systemic therapy for advanced disease .

Approximately 150 participants will be enrolled, and all enrolled participants will receive standard daily oral doses of camizestrant 75 mg and ribociclib 600 mg until treatment discontinuation.

Conditions: ER-Positive HER2-Negative Breast Cancer
Being tested: Camizestrant, Ribociclib
Keywords: Metastatic, Breast Neoplasms, Neoplasms by Site, Neoplasms, Breast Diseases, Next Generation Oral SERD, Antineoplastic Agents, Estrogen Receptor Antagonists, Camizestrant
Medical subject headings: Neoplasm Metastasis, Breast Neoplasms, Neoplasms by Site, Neoplasms, Breast Diseases

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

CamizestrantDrug
Also called AZD9833
Patients will receive the standard dose of camizestrant once daily as oral tablets
RibociclibDrug
Also called KISQALI®
Patients will receive the standard dose of ribociclib once daily as oral tablets

Study groups in NCT07647328
Study group	Role	What they receive
Camizestrant and Ribociclib	Experimental	Patients will receive the standard dose of camizestrant and ribociclib once daily as oral tablets Receives: Drug: Camizestrant; Drug: Ribociclib

What is being measured

The primary outcome is the main question the study is designed to answer.

Efficacy of camizestrant and ribociclib by time to next treatment (TTNT)
TTNT is defined as time from the date of the first administration of study treatment to the earliest start date of subsequent anti-cancer medication or death.
The primary measure of interest is the TTNT event-free rate at 2 years.
Measured: Following first dose of study treatment until earliest of subsequent therapy, death and 2 years after first dose of study treatment.

Secondary outcomes (3)

Efficacy of camizestrant and ribociclib by time to discontinuation (TTD)
TTD is defined as time from the date of the first administration of study treatment to the earliest date of camizestrant treatment discontinuation or death.
The primary measure of interest is the TTD event-free rate at 2 years.
Measured: Following first dose of study treatment until earliest of discontinuation of camizestrant, death and 2 years after first dose of study treatment
Efficacy of camizestrant and ribociclib by progression free survival (PFS)
PFS is defined as time from first dose of study treatment until progression per RECIST 1.1 as assessed by investigator or death due to any cause.
The primary measures of interest are the PFS event-free rates at 1 and 2 years.
Measured: Following first dose of study treatment until earliest of death, disease progression, and 2 years after first dose of study treatment.
CTCAE grade ≥ 3 associated with camizestrant and ribociclib within first 6 months of study treatment
Incidence of Grade >=3 CTCAEs associated with Camizestrant and/or Ribo within first 6 months of receiving study treatment.
Measured: Following first dose of study treatment until 6 months later

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

15 Jun 202628 Feb 2029

First posted15 Jun 2026
Study start15 Jun 2026
Primary completion28 Feb 2029 (estimated)
Study completion28 Feb 2029 (estimated)

Resources

Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
Other trials for ER-Positive HER2-Negative 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: Non-randomised
Intervention model: Single group
Model description: Interventional, prospective, single-arm, open-label study
Masking: None (open label)
Enrolment: 150 participants (estimated)

IDs, dates and publications

ClinicalTrials.gov ID: NCT07647328
Sponsor's protocol ID: D8532C00008
Acronym: SERAFA-1
Status last verified: Oct 2026
First submitted: 12 May 2026
Last updated: 19 Oct 2026
Results posted: No
Data monitoring committee: No
FDA-regulated drug: Yes
FDA-regulated device: No
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 requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure

Study at a glance

From the registry record, last updated by the sponsor on 19 Oct 2026. Recruitment status is as the sponsor reported it: confirm with the study team.

Official title: SERAFA-1: A Single Arm, Open Label, Multicentre, Phase IIIb Study Of Camizestrant Plus Ribociclib in 1st Line Treatment of ER Positive, HER2-negative Advanced Breast Cancer Patients
ClinicalTrials.gov ID: NCT07647328
Acronym / sponsor ID: SERAFA-1 / D8532C00008
Conditions: ER-Positive HER2-Negative Breast Cancer
Keywords: Metastatic, Breast Neoplasms, Neoplasms by Site, Neoplasms, Breast Diseases, Next Generation Oral SERD, Antineoplastic Agents, Estrogen Receptor Antagonists
Phase: Phase 3
Study type: Interventional
Recruitment status: Recruiting
Enrolment: 150 participants (estimated)
Lead sponsor: AstraZenecaIndustry (pharma, biotech, devices)
Collaborators: ICON plc
Study start: 15 Jun 2026 (actual)
Primary completion: 28 Feb 2029 (estimated)
Study completion: 28 Feb 2029 (estimated)
First posted: 15 Jun 2026 (actual)
Results: Not posted in the source record

Clinical summary

The research question as the sponsor registered it. This describes what the study plans to test, not what it found.

Detailed description

Approximately 150 participants will be enrolled, and all enrolled participants will receive standard daily oral doses of camizestrant 75 mg and ribociclib 600 mg until treatment discontinuation.

Study design

Primary purpose: Treatment
Allocation: Non-randomised
Intervention model: Single group
Masking: None (open label)
Number of arms: 1
Model description: Interventional, prospective, single-arm, open-label study

Arm	Type	Receives
Camizestrant and Ribociclib	Experimental	Drug: Camizestrant, Drug: RibociclibPatients will receive the standard dose of camizestrant and ribociclib once daily as oral tablets

Who may qualify

Ages: 18 to 130 years
Sex: All
Healthy volunteers: Not accepted
Age groups: Adult, Older adult

Key inclusion criteria (15 listed)

Capable of giving signed informed consent.
Female or male, must be ≥ 18 years or as per locally allowed age limit for screening.
Type of Participant and Disease Characteristics
Histologically or cytologically documented diagnosis of ER+, HER2- BC based on local laboratory results and who are not amenable to resection or radiation therapy with curative intent.
Previously untreated with any systemic anti-cancer therapy for their locoregionally recurrent or metastatic ER+ disease.

Key exclusion criteria (9 listed)

Participants who are not clinically indicated for endocrine therapy in combination with the CDK4/6 inhibitor ribociclib.
No evidence of advanced inoperable disease, or bone only disease with sclerotic/osteoblastic bone lesions only per standard of care imaging.
Have advanced, symptomatic, visceral spread, that are at risk of life-threatening complications in the short term, and/or pulmonary lymphangitis.
Persistent treatment-induced non-haematological toxicities (CTCAE Grade > 2).
Known active infection including tuberculosis HBV and HCV.

Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.

Interventions

Intervention	Type	Arms
CamizestrantAlso: AZD9833Patients will receive the standard dose of camizestrant once daily as oral tablets	Drug	Camizestrant and Ribociclib
RibociclibAlso: KISQALI®Patients will receive the standard dose of ribociclib once daily as oral tablets	Drug	Camizestrant and Ribociclib

Primary outcome

Efficacy of camizestrant and ribociclib by time to next treatment (TTNT)
Time frame: Following first dose of study treatment until earliest of subsequent therapy, death and 2 years after first dose of study treatment.
TTNT is defined as time from the date of the first administration of study treatment to the earliest start date of subsequent anti-cancer medication or death. The primary measure of interest is the TTNT event-free rate at 2 years.

3 secondary outcomes

Efficacy of camizestrant and ribociclib by time to discontinuation (TTD)
Time frame: Following first dose of study treatment until earliest of discontinuation of camizestrant, death and 2 years after first dose of study treatment
Efficacy of camizestrant and ribociclib by progression free survival (PFS)
Time frame: Following first dose of study treatment until earliest of death, disease progression, and 2 years after first dose of study treatment.
CTCAE grade ≥ 3 associated with camizestrant and ribociclib within first 6 months of study treatment
Time frame: Following first dose of study treatment until 6 months later

Results and safety

This study is still under way. Results are not available in the source record yet.

Research links

Official record on ClinicalTrials.govLast updated by the sponsor 19 Oct 2026.
Individual participant dataSharing planned: 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 requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure

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Referral and contact

AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.

AstraZeneca Clinical Study Information Center contact

1-877-240-9479

information.center@astrazeneca.com

89 sites in 9 countries: see every site and its status.

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Camizestrant and Ribociclib in people with ER-Positive HER2-Negative Breast Cancer, run by AstraZeneca at 89 sites in 9 countries.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 15 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 19 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 89 sites in Spain, South Korea, France, United States, Germany and 4 more countries. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact AstraZeneca Clinical Study Information Center (1-877-240-9479, information.center@astrazeneca.com), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Efficacy of camizestrant and ribociclib by time to next treatment (TTNT) (time frame: Following first dose of study treatment until earliest of subsequent therapy, death and 2 years after first dose of study treatment.). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT07647328.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 Oct 2026.