CCCA Assessed by Ki67 Drop Below <2.7% From BaselinePhase 2NCT06607757
Capivasertib Plus Fulvestrant vs. Fulvestrant in Primary High-risk Lobular Breast Cancer
A Phase 2 study testing Capivasertib and Fulvestrant injection in people with CCCA Assessed by Ki67 Drop Below <2.7% From Baseline, run by GBG Forschungs GmbH at 25 sites in Germany.
Trial summary
This is a multicenter, prospective, open-label, randomized phase II study to evaluate the CCCA assessed by Ki67 drop below \<2.7% from baseline to week 2 (window of opportunity) and to week 10 with capivasertib plus fulvestrant compared with fulvestrant alone as neoadjuvant treatment for primary high-risk lobular… Read more about this study
- Who is it for?
- Ages 18 years and older, women only
- Conditions the study is for
- CCCA Assessed by Ki67 Drop Below <2.7% From Baseline
- What is being tested?
- Capivasertib and Fulvestrant injection
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 120 participants
- Where
- 25 sitesGermany
- Study dates
- 4 Dec 2024to 31 Aug 2026
- Phase
- Phase 2
- 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 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Written informed consent prior to beginning specific protocol procedures, including expected cooperation of the patients for the treatment and followup, and documented according to the local regulatory requirements.
- Postmenopausal women with age at diagnosis ≥ 18 years.
- Postmenopausal status is defined as:
- Age ≥60 years
- Age <60 years and amenorrhea for at least 12 continuous months with no identified cause other than menopause
- Bilateral oophorectomy Negative pregnancy test (urine or serum) within 14 days prior to randomization for all postmenopausal women 50 years of age or younger without bilateral oophorectomy
Show all 26Show fewer
- Unilateral or bilateral primary untreated lobular invasive carcinoma of the breast. In case of bilateral breast cancer, both sides must be lobular; the lead tumor has to be defined by the investigator based on the inclusion criteria for the respective subtype and the risk status. Lobular histology has to be centrally confirmed.
- Willingness and ability to provide archived formalin fixed paraffin embedded (FFPE) tissue block from core biopsy before the start of neoadjuvant therapy.
- Centrally confirmed HER2-negative (IHC score 0-1+ or ISH negative according to ASCO/CAP guideline) and HR-positive (≥10% positive stained cells) disease, assessed on the core of diagnostic biopsy. Ki67% >10% is required. In case of bilateral breast cancer, HER2-negative, HR-positive and lobular histology status has to be confirmed for both sides.
- Patients with invasive lobular breast cancer at high risk for recurrence defined as cT1c and clinical nodal involvement (cN+) or ≥ cT2 disease (irrespective of nodal involvement).
- No clinical evidence of distant metastases.
- Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0 or 1.
- Estimated life expectancy of at least 5 years irrespective of the diagnosis of breast cancer.
- The patient must be accessible for scheduled visits, treatment, and followup.
- Normal cardiac function must be confirmed according to local guidelines.
- Laboratory requirements:
- Hematology
- Absolute neutrophil count (ANC) ≥1.5 x 109 / L
- Platelets ≥100 x 109 / L
- Hemoglobin ≥10 g/dL (≥6.2 mmol/L) Hepatic function
- Total bilirubin <1.25x ULN
- AST and ALT <=1.5x ULN
- Alkaline phosphatase <=2.5x ULN Glucose Metabolism
- HbA1c <8.0% (63.9 mmol/mol) Renal Function
- Creatinine <1.25x ULN or creatinine clearance ≥50 ml/min (if creatinine is above ULN according to Cockroft-Gault)
- Complete staging work-up prior to the initiation of neoadjuvant therapy as per standard recommendations.
Who cannot join
- Female patients of childbearing potential.
- Excisional biopsy or lumpectomy performed prior to study entry.
- Surgical axillary staging procedure including sentinel lymph node biopsy prior to randomization. Exceptions: FNA or core biopsy of an axillary lymph node.
- Any previous treatment including endocrine therapy, chemotherapy, radiotherapy or targeted therapy (including AKT inhibitor or PIK3 inhibitor) for the currently diagnosed breast cancer.
- Concurrent use of herbal or natural products intended as treatment or prophylaxis for any type of cancer.
- Known hypersensitivity reaction to one of the compounds or substances used in this protocol.
Show all 25Show fewer
- Potent inhibitors or inducers of CYP3A4 within 2 weeks prior to the first dose of study treatment (3 weeks for St John's wort).
- Refractory nausea and vomiting, chronic gastrointestinal disease, inability to swallow the formulated product, or previous significant bowel resection that would preclude adequate absorption, distribution, metabolism, or excretion of capivasertib.
- Any contraindication for fulvestrant.
- Patients with definitive clinical or radiologic evidence of stage IV cancer (metastatic disease) are not eligible.
- Patients with a history of any malignancy are ineligible with the following exceptions:
- Patient has been disease-free for at least 5 years and is at low risk for recurrence of that malignancy except for breast cancer.
- CIS of the cervix, basal cell and squamous cell carcinomas of the skin.
- History of type I or type II diabetes mellitus requiring insulin.
- Severe and relevant co-morbidity that would interact with the application of study drugs or the participation in the study, including cerebrovascular incident including transient ischemic attack, or symptomatic pulmonary embolism, active infection requiring intravenous anti-microbial treatment (antibiotics, anti-fungal, and anti-viral drugs) within 1 week of enrolment. Patients with confirmed Gilbert's syndrome may be included in the study.
- Known medically history of HIV infection, tuberculosis, or hepatitis B.
- History of and/or active cardiac disease that would preclude the use of study treatments. This includes but is not confined to any of the following cardiac criteria:
- Clinically significant cardiac dysfunction including heart failure (NYHA II-IV), active ventricular arrhythmias requiring medication or arrhythmias requiring a pacemaker, and history of a myocardial infarction within 6 months prior to randomization, angina pectoris, atrial fibrillation of any grade, coronary/peripheral artery bypass graft, angioplasty, or vascular stent.
- Mean resting QT interval corrected by Fridericia's formula (QTcF) >470 msec obtained from 3 consecutive ECGs.
- Increased risk of QTc prolongation or risk of arrhythmic events such as heart failure, uncontrolled electrolyte disorders (e.g., hypocalcemia, hypokalemia, or hypomagnesemia), potential for torsades de pointes, congenital long QT syndrome, family history of long QT syndrome or unexplained sudden death under 40 years of age, or any concomitant medication known to prolong the QT interval.
- Receipt of live attenuated vaccination within 30 days prior to study entry or within 30 days of receiving therapy.
- History of significant neurological or psychiatric disorders including psychotic disorders, dementia, or seizures that would prohibit the understanding and giving of informed consent.
- Any condition that, in the opinion of the investigator, would interfere with evaluation of study treatment or interpretation of patient safety or study results (such as severe or uncontrolled systemic diseases, including uncontrolled hypertension or hypotension (BP <50mmHg), significant aneurysm, renal transplant and active bleeding diseases).
- Major surgical procedure (excluding placement of vascular access) or significant traumatic injury within 4 weeks of the first dose of study intervention or an anticipated need for major surgery during the study.
- Participation in another clinical study with a study intervention or investigational medicinal device administered in the 4 weeks prior to first dose of study intervention or concurrent enrolment in another clinical study unless it is an observational (non-interventional) clinical study or during the follow-up period of an interventional study.
Trial locations and contacts
25 sites in 1 country. Contact the study team or a site near you to ask about taking part.
25 sites in 1 country
Germany25 sites, 10 recruiting
- Recruiting
Haematologie-Onkologie im Zentrum MVZ GmbH
Augsburg, 86150
Heinrich, Dr. med., +49-821-3446-50, bernhard.heinrich@hop-augsburg.de
- Active, not recruiting
Charité
Berlin, 10117
- Recruiting
Onkologische Schwerpunktpraxis - Studiengesellschaft Onkologie Bielefeld GbR
Bielefeld, 33604
Steinke, Dr. med., +49-521-9887-770, siemke.steinke@onkologie-bielefeld.de
- Active, not recruiting
Hämato-Onkologie im Medicum - Onkologie und Hämatologie
Bremen, 28209
- Active, not recruiting
Kliniken der Stadt Köln GmbH - Brustzentrum Köln-Holweide
Cologne, 51067
- Active, not recruiting
Carl-Thiem-Klinikum gGmbH - Frauenklinik
Cottbus, 03048
- Active, not recruiting
Kath. St. Paulus GmbH - Klinische Forschung
Dortmund, 44137
- Recruiting
Universitätsklinikum Essen - Klinik für Frauenheilkunde und Geburtshilfe
Essen, 45147
Bittner, Prof. Dr. med., +49-201-7230, Ann-Kathrin.Bittner@uk-essen.de
- Active, not recruiting
Klinikum Frankfurt Höchst GmbH - Klinik für Gynäkologie und Geburtshilfe
Frankfurt am Main, 65929
- Active, not recruiting
Praxis für Interdisziplinäre Onkologie & Hämatologie
Freiburg im Breisgau, 79110
- Recruiting
Mammazentrum Hamburg - am Krankenhaus Jerusalem
Hamburg, 20357
Schem, Prof. Dr. med., +49-404-4190-500, schem@mammazentrum.eu
- Active, not recruiting
Universitätsklinikum des Saarlandes - Frauenklinik
Homburg, 66424
- Not yet recruiting
Klinikum Kassel GmbH - Frauenklinik
Kassel, 34125
Dautzenberg, Dr. med., +49-561-9800, lydia.dautzenberg@gnh.net
- Recruiting
St. Elisabethen-Krankenhaus gGmbH - Senologie / Brustzentrum
Leipzig, 04277
Langanke, Dr. med., +49-341-3959-7450, dagmar.langanke@ek-leipzig.de
- Recruiting
Medizinisches Versorgungszentrum MediaVita GmbH Muenster
Münster, 48145
Eichler, Dr. med., +49-251-935-0, christian.eichler@sfh-muenster.de
- Active, not recruiting
Klinikum Oldenburg AöR - Universitätsklinik für Innere Medizin - Onkologie
Oldenburg, 26133
- Active, not recruiting
MVZ für Hämatolgie und Onkologie Ravensburg GmbH - Studienzentrum
Ravensburg, 88212
- Active, not recruiting
Klinikum Südstadt - Universitätsfrauenklinik
Rostock, 18059
- Recruiting
Leopoldina-Krankenhaus der Stadt Schweinfurt - Frauenklinik
Schweinfurt, 97422
Wiegand, Dr. med., +49-9721-7200, ewiegand@leopoldina.de
- Active, not recruiting
Johanniter-Krankenhaus Genthin-Stendal - Klinik für Frauenheilkunde und Geburtshilfe
Stendal, 39576
- Active, not recruiting
Kreiskrankenhaus Torgau - Gynäkologie
Torgau, 04860
- Active, not recruiting
Praxisnetzwerk Haematologie und internistische Onkologie Ueberoertliche Berufsausuebungsgemeinschaft - Hämatologie und Onkologie
Troisdorf, 53840
- Active, not recruiting
Marienhospital Witten - Brustzentrum
Witten, 58452
- Recruiting
Klinikum Worms gGmbH - Frauenklinik
Worms, 67550
Züfle, Dr. med., +49-6241-5010, ebastian.zuefle@klinikum-worms.de
- Recruiting
Helios Klinikum Wuppertal GmbH - Landesfrauenklinik
Wuppertal, 42283
Bjelic- Radisic, Prof. Dr. med., +49 2028961411, Vesna.Bjelic-Radisic@helios-gesundheit.de
About this study
Official title: Phase II Neoadjuvant Study Evaluating Capivasertib Plus Fulvestrant vs Fulvestrant in Patients With Primary High-risk Lobular Breast Cancer- LOBSTER
This is a multicenter, prospective, open-label, randomized phase II study to evaluate the CCCA assessed by Ki67 drop below \<2.7% from baseline to week 2 (window of opportunity) and to week 10 with capivasertib plus fulvestrant compared with fulvestrant alone as neoadjuvant treatment for primary high-risk lobular breast cancer patients.
120 patients will be randomized to receive:
Read more
- Capivasertib (400 mg po twice daily d1-4 followed by 3 days off) for 2 weeks followed by capivasertib (400 mg po twice daily d1-4 followed by 3 days off) and fulvestrant (500 mg i.m. q28d, with an additional 500 mg dose given two weeks after the initial dose) for additional 8 weeks (overall 4 administrations of fulvestrant) or
- Fulvestrant (500mg i.m. q28d, with an additional 500 mg dose given two weeks after the core biopsy and the initial dose) for 10 weeks (overall 4 administrations) Treatment will be given until surgery/core-biopsy, disease progression, unacceptable toxicity, or withdrawal of consent of the patient.
All patients will undergo core-biopsies, under treatment and after completing study therapy in order to assess Ki67%. Further treatment including surgery, (neo)adjuvant chemotherapy, radiotherapy, and (neo)adjuvant endocrine therapy will be administered at the discretion of the investigator and according to standard of care outside the clinical trial.
Read the detailed description
The evaluation of CCCA in the HR+/HER2- invasive lobular breast cancer patient population allows assessment of treatment efficacy with an achievable sample size of HR+/HER2- breast cancer patients within an acceptable and scientifically meaningful duration of recruitment. CCCA can be assessed immediately after last patients end of treatment. Central blinded pathological assessment of CCCA is planned in this study as a standardized preparation of the sampled tissue by the central pathologist. This pathologist is blinded regarding the study therapy administered, i. e. with or without capivasertib.
The addition of capivasertib to fulvestrant in many clinical trials correlates with an improvement in PFS compared to fulvestrant alone in patients with HR+/HER2- locally advanced or metastatic breast cancer. This effect was observed regardless of a PI3K/AKT/mTOR pathway activation. None of the ongoing studies investigate the effects of the combined treatment in invasive lobular breast cancer. Given that these tumors are less likely to respond to chemotherapy, identification of patients that can be spared from chemotherapy is desirable. On the other hand, it is important to identify patients with invasive lobular breast cancer not responding to neoadjuvant ET who might be at increased risk for recurrence, who would therefore potentially benefit from further adjuvant therapies including chemotherapy.
Given the high rates of PI3K pathway alterations in such tumors, it is expected that the CCCA rate could be increased by adding capivasertib to fulvestrant. GBG expect that the potential benefit of improved CCCA rate with a combination treatment compared to fulvestrant monotherapy would outweigh the potential risks due to added toxicity, which has already been shown in clinical trials to be well tolerated by patients.
- Being tested
- Capivasertib, Fulvestrant injection
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CapivasertibDrug
Also called Truqap
find arm A description
Fulvestrant injectionDrug
Also called Faslodex
find arm B description
| Study group | Role | What they receive |
|---|---|---|
| Arm A | Experimental | Capivasertib (400 mg po twice daily d1-4 followed by 3 days off) for 2 weeks followed by capivasertib (400 mg po twice daily d1-4 followed by 3 days off) and fulvestrant (500 mg i.m. q28d, with an additional 500 mg dose given two weeks after the initial dose) for additional 8 weeks (overall 4 administrations of fulvestrant) Receives: Drug: Capivasertib; Drug: Fulvestrant injection |
| Arm B | Active comparator | Fulvestrant (500mg i.m. q28d, with an additional 500 mg dose given two weeks after the core biopsy and the initial dose) for 10 weeks (overall 4 administrations) Receives: Drug: Fulvestrant injection |
What is being measured
The primary outcome is the main question the study is designed to answer.
To assess complete cell cycle arrest (CCCA).
The primary endpoint CCCA is defined as Ki67 drop to \<2.7% after approximately 10 weeks (will be assessed centrally on the breast tissue submitted to central pathology)
Measured: Up to 14 weeks
Secondary outcomes (4)
To asses safety and tolerability
Tolerability and safety analyses include assessment of patients whose treatment had to be dose reduced, delayed or permanently stopped.
Measured: Up to 14 weeks
To assess patholgogical complete response rate (pCR) by different definitions
Pathological complete response (pCR ypT0 ypN0) is defined as no microscopic evidence of residual invasive and non-invasive viable tumor cells in all resected specimens of the breast and axilla.
Measured: Up to 14 weeks
To assess breast conservation rate (BCS)
BCS is defiened as tumorectomy, segmentectomy or quandrantectomy as the most radical surgery.
Measured: Up to 14 weeks
To assess invasive disease-free survival (iDFS) and overall survival (OS)
iDFS is defined as time from randomization until first iDFS event OS is defined as time from randomization until death due to any cause
Measured: through study completion, an average of 2 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Sep 2024
- Study start4 Dec 2024
- Primary completion30 Jun 2026 (estimated)
- Study completion31 Aug 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for CCCA Assessed by Ki67 Drop Below <2.7% From BaselineStudies of the same condition, open and under way.
- 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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Evaluation of treatment outcome
- Masking
- None (open label)
- Enrolment
- 120 participants (estimated)
Sponsor and investigators
- Lead sponsor
- GBG Forschungs GmbH
- Sponsor type
- University, hospital or other
- Collaborators
- AstraZeneca
- Responsible party
- Sponsor
- Investigators
- Sibylle Loibl, Prof. Dr. med., Principal investigator, ESMO, ASCO, AGO Kommission Mamma (member); Goethe University Frankfurt; GBG Forschungs GmbH
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06607757
- Sponsor's protocol ID
- GBG118 - LOBSTER
- Other IDs
- 2023-509292-17-00, 2023
- Status last verified
- Mar 2025
- First submitted
- 14 Jun 2024
- Last updated
- 2 Apr 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Rugo HS, Oliveira M, Howell SJ, Dalenc F, Cortes J, Gomez HL, Hu X, Jhaveri KL, Krivorotko P, Loibl S, Morales Murillo S, Nowecki Z, Okera M, Park YH, Sohn J, Toi M, Iwata H, Yousef S, Zhukova L, Logan J, Twomey K, Khatun M, D'Cruz CM, Turner NC. Capivasertib and fulvestrant for patients with hormone receptor-positive advanced breast cancer: characterization, time course, and management of frequent adverse events from the phase III CAPItello-291 study. ESMO Open. 2024 Sep;9(9):103697. doi: 10.1016/j.esmoop.2024.103697. Epub 2024 Sep 5.
PubMed 39241495
Study at a glance
From the registry record, last updated by the sponsor on 2 Apr 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Phase II Neoadjuvant Study Evaluating Capivasertib Plus Fulvestrant vs Fulvestrant in Patients With Primary High-risk Lobular Breast Cancer- LOBSTER
- ClinicalTrials.gov ID
- NCT06607757
- Acronym / sponsor ID
- GBG118 - LOBSTER
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 120 participants (estimated)
- Lead sponsor
- GBG Forschungs GmbHUniversity, hospital or other
- Collaborators
- AstraZeneca
- Study start
- 4 Dec 2024 (actual)
- Primary completion
- 30 Jun 2026 (estimated)
- Study completion
- 31 Aug 2026 (estimated)
- First posted
- 23 Sep 2024 (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.
This is a multicenter, prospective, open-label, randomized phase II study to evaluate the CCCA assessed by Ki67 drop below \<2.7% from baseline to week 2 (window of opportunity) and to week 10 with capivasertib plus fulvestrant compared with fulvestrant alone as neoadjuvant treatment for primary high-risk lobular breast cancer patients.
120 patients will be randomized to receive:
- Capivasertib (400 mg po twice daily d1-4 followed by 3 days off) for 2 weeks followed by capivasertib (400 mg po twice daily d1-4 followed by 3 days off) and fulvestrant (500 mg i.m. q28d, with an additional 500 mg dose given two weeks after the initial dose) for additional 8 weeks (overall 4 administrations of fulvestrant) or
- Fulvestrant (500mg i.m. q28d, with an additional 500 mg dose given two weeks after the core biopsy and the initial dose) for 10 weeks (overall 4 administrations) Treatment will be given until surgery/core-biopsy, disease progression, unacceptable toxicity, or withdrawal of consent of the patient.
All patients will undergo core-biopsies, under treatment and after completing study therapy in order to assess Ki67%. Further treatment including surgery, (neo)adjuvant chemotherapy, radiotherapy, and (neo)adjuvant endocrine therapy will be administered at the discretion of the investigator and according to standard of care outside the clinical trial.
Detailed description
The evaluation of CCCA in the HR+/HER2- invasive lobular breast cancer patient population allows assessment of treatment efficacy with an achievable sample size of HR+/HER2- breast cancer patients within an acceptable and scientifically meaningful duration of recruitment. CCCA can be assessed immediately after last patients end of treatment. Central blinded pathological assessment of CCCA is planned in this study as a standardized preparation of the sampled tissue by the central pathologist. This pathologist is blinded regarding the study therapy administered, i. e. with or without capivasertib.
The addition of capivasertib to fulvestrant in many clinical trials correlates with an improvement in PFS compared to fulvestrant alone in patients with HR+/HER2- locally advanced or metastatic breast cancer. This effect was observed regardless of a PI3K/AKT/mTOR pathway activation. None of the ongoing studies investigate the effects of the combined treatment in invasive lobular breast cancer. Given that these tumors are less likely to respond to chemotherapy, identification of patients that can be spared from chemotherapy is desirable. On the other hand, it is important to identify patients with invasive lobular breast cancer not responding to neoadjuvant ET who might be at increased risk for recurrence, who would therefore potentially benefit from further adjuvant therapies including chemotherapy.
Given the high rates of PI3K pathway alterations in such tumors, it is expected that the CCCA rate could be increased by adding capivasertib to fulvestrant. GBG expect that the potential benefit of improved CCCA rate with a combination treatment compared to fulvestrant monotherapy would outweigh the potential risks due to added toxicity, which has already been shown in clinical trials to be well tolerated by patients.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Evaluation of treatment outcome
| Arm | Type | Receives |
|---|---|---|
| Arm A | Experimental | Drug: Capivasertib, Drug: Fulvestrant injectionCapivasertib (400 mg po twice daily d1-4 followed by 3 days off) for 2 weeks followed by capivasertib (400 mg po twice daily d1-4 followed by 3 days off) and fulvestrant (500 mg i.m. q28d, with an additional 500 mg dose given two weeks after the initial dose) for additional 8 weeks (overall 4 administrations of fulvestrant) |
| Arm B | Active comparator | Drug: Fulvestrant injectionFulvestrant (500mg i.m. q28d, with an additional 500 mg dose given two weeks after the core biopsy and the initial dose) for 10 weeks (overall 4 administrations) |
Who may qualify
- Ages
- 18 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (26 listed)
- Written informed consent prior to beginning specific protocol procedures, including expected cooperation of the patients for the treatment and followup, and documented according to the local regulatory requirements.
- Postmenopausal women with age at diagnosis ≥ 18 years.
- Unilateral or bilateral primary untreated lobular invasive carcinoma of the breast. In case of bilateral breast cancer, both sides must be lobular; the lead tumor has to be defined by the investigator based on the inclusion criteria for the respective subtype and the risk status. Lobular histology has to be centrally confirmed.
- Willingness and ability to provide archived formalin fixed paraffin embedded (FFPE) tissue block from core biopsy before the start of neoadjuvant therapy.
- Centrally confirmed HER2-negative (IHC score 0-1+ or ISH negative according to ASCO/CAP guideline) and HR-positive (≥10% positive stained cells) disease, assessed on the core of diagnostic biopsy. Ki67% >10% is required. In case of bilateral breast cancer, HER2-negative, HR-positive and lobular histology status has to be confirmed for both sides.
Key exclusion criteria (25 listed)
- Female patients of childbearing potential.
- Excisional biopsy or lumpectomy performed prior to study entry.
- Surgical axillary staging procedure including sentinel lymph node biopsy prior to randomization. Exceptions: FNA or core biopsy of an axillary lymph node.
- Any previous treatment including endocrine therapy, chemotherapy, radiotherapy or targeted therapy (including AKT inhibitor or PIK3 inhibitor) for the currently diagnosed breast cancer.
- Concurrent use of herbal or natural products intended as treatment or prophylaxis for any type of cancer.
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 |
|---|---|---|
| CapivasertibAlso: Truqapfind arm A description | Drug | Arm A |
| Fulvestrant injectionAlso: Faslodexfind arm B description | Drug | Arm A, Arm B |
Primary outcome
To assess complete cell cycle arrest (CCCA).
Time frame: Up to 14 weeks
The primary endpoint CCCA is defined as Ki67 drop to \<2.7% after approximately 10 weeks (will be assessed centrally on the breast tissue submitted to central pathology)
4 secondary outcomes
To asses safety and tolerability
Time frame: Up to 14 weeks
To assess patholgogical complete response rate (pCR) by different definitions
Time frame: Up to 14 weeks
To assess breast conservation rate (BCS)
Time frame: Up to 14 weeks
To assess invasive disease-free survival (iDFS) and overall survival (OS)
Time frame: through study completion, an average of 2 years
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 2 Apr 2025.
- Background: PubMed 39241495Rugo HS, Oliveira M, Howell SJ, Dalenc F, Cortes J, Gomez HL, Hu X, Jhaveri KL, Krivorotko P, Loibl S, Morales Murillo S, Nowecki Z, Okera M, Park YH, Sohn J, Toi M, Iwata H, Yousef S, Zhukova L, Logan J, Twomey K, Khatun M, D'Cruz CM, Turner NC. Capivasertib and fulvestrant for patients with hormone receptor-positive advanced breast cancer: characterization, time course, and management of frequent adverse events from the phase III CAPItello-291 study. ESMO Open. 2024 Sep;9(9):103697. doi: 10.1016/j.esmoop.2024.103697. Epub 2024 Sep 5.
- GBG Website with information about LOBSTER TrialLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided
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.
Sibylle Loibl, Prof. Dr. med. principal investigator
ESMO, ASCO, AGO Kommission Mamma (member); Goethe University Frankfurt; GBG Forschungs GmbH
25 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Capivasertib and Fulvestrant injection in people with CCCA Assessed by Ki67 Drop Below <2.7% From Baseline, run by GBG Forschungs GmbH at 25 sites in Germany.
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 26 inclusion and 25 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 2 Apr 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 25 sites in Germany. 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 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
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 Christina Müller-Weisbrod (+49610274800, LOBSTER@gbg.de), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
To assess complete cell cycle arrest (CCCA). (time frame: Up to 14 weeks). 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 NCT06607757, which also lists 1 linked publication.
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 2 Apr 2025.