Metastatic Breast CancerPhase 2TATENNCT04251169
Pembrolizumab + Paclitaxel in HR+/HER2- Non-luminal (by PAM50) Advanced Breast Cancer After CDK4/6 Inhibitor Progression
A Phase 2 study testing Pembrolizumab and Paclitaxel in people with Metastatic Breast Cancer, run by SOLTI Breast Cancer Research Group at 7 sites in Spain.
Trial summary
This is an open-label, single arm, multicenter phase II study evaluating treatment with pembrolizumab in combination with paclitaxel in patients with locally advanced or metastatic non-luminal hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) (hereafter referred to as… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Metastatic Breast Cancer
- What is being tested?
- Pembrolizumab and Paclitaxel
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 20 participants
- Where
- 7 sitesSpain
- Study dates
- 21 Jul 2020to 30 Apr 2024
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
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
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Male/female participants who are at least 18 years of age on the day of signing informed consent with histologically confirmed diagnosis of locally advanced or metastatic, histologically documented hormone receptor positive (estrogen receptor [ER] and/or progesterone receptor [PR] expression >1%) and human epidermal growth factor receptor 2-negative (HER2-) breast cancer by local testing, not amenable to surgical therapy will be enrolled in this study.
- HER2 negativity is defined as either of the following by local laboratory assessment: Immunohistochemistry (IHC) 0, IHC 1+ or IHC 2+/in situ hybridisation (ISH) negative as per American Society of Clinical Oncology (ASCO)-College of American Pathologists Guideline (CAP) guideline (ISH negative is defined as a ratio of HER2 to chromosome 17 centromere (CEP17) <2.0)117.
- ER and/or PR positivity are defined as >1% of cells expressing HR via IHC analysis as per ASCO-CAP guideline118
- The participant (or legally acceptable representative if applicable) provides written informed consent for the trial.
- Eligible for taxane therapy.
- No prior chemotherapy for inoperable locally advanced or metastatic breast cancer.
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- Prior radiation therapy for metastatic disease is permitted. Subjects who were treated with radiation therapy may participate as long as at least 2 weeks have elapsed since the last dose of radiation therapy or have recovered from the effects of radiation before allocation whichever is the latest.
- Disease refractory to CDK4/6 inhibitors, defined as recurrence during or within 12 months after the end of adjuvant treatment or progression during or within 6 months after the end of treatment for advanced/metastatic disease.
- Notes: CDK4/6 inhibitors do not have to be the last treatment prior to randomization. Other prior anticancer endocrine therapy, e.g. aromatase inhibitors, fulvestrant or tamoxifen, are also allowed.
- Previous chemotherapy with a taxane for early breast cancer (neoadjuvant or adjuvant setting) is permitted.
- Availability of formalin-fixed paraffin-embedded (FFPE) tumor block, collected during advanced/metastatic disease, with an associated pathology report. The tumor tissue should be of good quality based on total and viable tumor content and must be evaluated centrally for PAM50 analysis prior to enrollment. Patients whose tumor tissue is not evaluable for central testing are not eligible. If PAM50 analysis of tumor sample has alredy been performed at central lab (i.e analysis from other SOLTI clinical trial) PAM50 result can be valid for this study.
- Acceptable samples include core needle biopsies for deep tumor tissue or excisional, incisional, punch, or forceps biopsies for cutaneous, subcutaneous, or mucosal lesions or biopsies from bone metastases.
- Fine needle aspiration, brushing, cell pellet from pleural effusion and lavage samples are not acceptable.
- Non-Luminal subtype as per PAM50 analysis (i.e. HER2-enriched or Basal-like).
- Have an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1. Evaluation of ECOG is to be performed within 10 days prior to the date of allocation/randomization.
- Life expectancy ≥ 12 weeks
- Measurable disease, as defined by Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v1.1). (Note: Previously irradiated lesions can be considered as measurable disease only if disease progression has been unequivocally documented at that site since radiation.)
- Adequate hematologic and end-organ function, defined by the study protocol with results obtained within 10 days prior to the first study treatment at Cycle 1, Day 1 (C1D1):
- Male participants:
- A male participant must agree to use contraception during the treatment period and for at least 180 days after the last dose of paclitaxel and 120 days form the last doses of pembrolizumab and refrain from donating sperm during this period.
- Female participants:
- A female participant is eligible to participate if she is not pregnant not breastfeeding, and at least one of the following conditions applies: a.) Not a woman of childbearing potential (WOCBP) as defined in Appendix 3 OR b.) A WOCBP who agrees to follow the contraceptive guidance in Appendix 3 during the treatment period and for at least 180 days after the last dose of paclitaxel and 120 days from the last dose of pembrolizumab.
Who cannot join
- A WOCBP who has a positive urine pregnancy test within 72 hours prior to Cycle 1, Day 1 (C1D1). If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required.
- Has received prior therapy with an anti-PD1, anti-PD-L1, or anti-PD-L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor.
- History of hypersensitivity reactions to paclitaxel or other drugs formulated in the same solvent as paclitaxel (polyoxyethylated castor oil).
- Resolution of all acute toxic effects of prior anti-cancer therapy or major surgical procedures to National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 (NCI CTCAE v5.0) Grade ≤ 1 (except alopecia or other toxicities not considered a safety risk for the patient at investigator´s discretion).
- Note: Placement of central venous access catheter(s) (e.g., port or similar) is not considered a major surgical procedure and is therefore permitted.
- Has received a live vaccine within 30 days prior to the first dose of study drug. Examples of live vaccines include, but are not limited to, the following: measles, mumps, rubella, varicella/zoster (chicken pox), yellow fever, rabies, Bacillus Calmette-Guérin (BCG), and typhoid vaccine. Seasonal influenza vaccines for injection are generally killed virus vaccines and are allowed; however, intranasal influenza vaccines (eg, FluMist®) are live attenuated vaccines and are not allowed. Note: It is not recommended the use of live or attenuated COVID-19 vaccines within 30 days of initiation or during study treatment. However, if vaccination with these vaccines is required, please ask for advice on how to proceed the Medical Monitor.
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- Uncontrolled pleural effusion, pericardial effusion, or ascites (Note: patients with indwelling catheters, such as PleurX® are allowed).
- Uncontrolled hypercalcemia (>1.5 mmol/L [>6 mg/dL] ionized calcium or serum calcium [uncorrected for albumin] >3 mmol/L [>12 mg/dL] or corrected serum calcium >upper limit of normal (ULN) or clinically significant (symptomatic) hypercalcemia
- Has a diagnosis of immunodeficiency or is receiving chronic systemic steroid therapy (in dosing exceeding 10 mg daily of prednisone equivalent) or any other form of immunosuppressive therapy within 7 days prior to the first dose of study drug.
- Has a known additional malignancy that is progressing or has required active treatment within the past 3 years. Note: Participants with basal cell carcinoma of the skin, squamous cell carcinoma of the skin or carcinoma in situ (e.g. breast carcinoma, cervical cancer in situ) that have undergone potentially curative therapy are not excluded.
- Has known active Central Nervous System metastases and/or carcinomatous meningitis. Participants with previously treated brain metastases may participate provided they are radiologically stable, i.e. without evidence of progression for at least 4 weeks by repeat imaging (note that the repeat imaging should be performed during study screening), clinically stable and without requirement of steroid treatment for at least 14 days prior to first dose of study treatment.
- Has severe hypersensitivity (≥Grade 3) to pembrolizumab and/or any of its excipients.
- Has active autoimmune disease that has required systemic treatment in the past 2 years (i.e. with use of disease modifying agents, corticosteroids or immunosuppressive drugs). Replacement therapy (eg., thyroxine, insulin, or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a form of systemic treatment.
- Has a history of (non-infectious) pneumonitis/interstitial lung disease that required steroids or has current pneumonitis/interstitial lung disease.
- Prior allogeneic stem cell or solid organ transplantation
- Has an active infection requiring systemic therapy.
- Has a known history of Human Immunodeficiency Virus (HIV).
- Has a known history of Hepatitis B (defined as Hepatitis B surface antigen [HBsAg] reactive) or known active Hepatitis C virus (HCV) (defined as HCV RNA [qualitative] is detected) infection. Note: no testing for Hepatitis B and Hepatitis C is required unless mandated by local health authority.
- Has a known history of active Tuberculosis Bacillus.
- Has a history or current evidence of any condition, therapy, or laboratory abnormality that might confound the results of the study, interfere with the subject's participation for the full duration of the study, or is not in the best interest of the subject to participate, in the opinion of the treating investigator.
- Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial.
- Is pregnant or breastfeeding or expecting to conceive or father children within the projected duration of the study, starting with the screening visit through 120 days after the last dose of pembrolizumab or 180 days after the last dose of paclitaxel.
Trial locations and contacts
7 sites in 1 country.
7 sites in 1 country
Spain7 sites
Hospital Universitari Vall d'Hebrón
Barcelona, 08035
Hospital Clinic de Barcelona
Barcelona
ICO Hospitalet
L'Hospitalet de Llobregat, Barcelona
Hospital Universitario 12 de octubre
Madrid
Hospital Quiron Salud Sagrado Corazon Sevilla
Seville
Fundación Instituto Valenciano de Oncología
Valencia, 46009
Hospital Clínico Universitario de Valencia
Valencia
About this study
Official title: Targeting Non-Luminal Disease by PAM50 With Pembrolizumab + Paclitaxel in Hormone Receptor-positive/HER2-negative Advanced/Metastatic Breast Cancer, Who Have Progressed on or After CDK 4/6 Inhibitor Treatment
This is an open-label, single arm, multicenter phase II study evaluating treatment with pembrolizumab in combination with paclitaxel in patients with locally advanced or metastatic non-luminal hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) (hereafter referred to as HR+/HER2-) breast cancer who had recurrence or progression while receiving previous therapy with a cyclin-dependent kinase (CDK) inhibitor in the adjuvant setting or to treat advanced disease (or both).
Read the detailed description
The study will utilize a 2-stage, single arm, Simon's 2-stage design with one (efficacy) interim and a final analysis. The interim analysis will be conducted when 15 patients are evaluable for Overall Response Rate (ORR) as determined locally by the investigator through the use of Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v.1.1). If 5 or fewer responses are observed in up to 15 patients of the evaluable population (EP), the trial will be terminated in favor of the null for futility. Otherwise, up to a further 31 patients may be evaluated, for a maximum total of 46 evaluable patients. If a total of 19 or more responses are seen at the end of the second stage, then the null will have been rejected in favor of the alternative; and further investigation of the combination is warranted.
Recruitment will not be halted during the interim analysis period. Therefore, no interruption in the accrual will be done during the interim analysis in order to maintain the dynamic of accrual in the trial.
After confirmation of all eligibility criteria, eligible patients will receive pembrolizumab 200 mg every 3 weeks (on Day 1 [D1] of each 21-day cycle, beginning in Cycle 1) in combination with paclitaxel 80 mg/m² administered at Days 1, 8, and 15 of each 21-day cycle beginning at Cycle 2. Treatment will continue until disease progression, the development of unacceptable toxicity, withdrawal of consent, 24 months from the date of the first dose of pembrolizumab, or end of study, whichever occurs first.
All patients will be followed for survival from screening until the last patient recruited has been followed for 12 months, has progressed, or has died, whichever occurs first. The patient will be followed for survival approximately every 3 months (± 21 days) until death, withdrawal of consent, loss to follow-up, or study termination by the sponsor. In addition, information regarding use of subsequent anti-cancer agents for metastatic hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) during the survival follow-up period will be collected.
Tumor assessments per RECIST v.1.1 and Immune-Related Response Evaluation Criteria in Solid Tumors (iRECIST) will be performed every 9 weeks (63 days ± 5 days) until disease progression, treatment discontinuation, the start of new anti-cancer treatment, withdrawal of consent, death, or the end of the study, whichever occurs first. Tumor assessments will be performed on the specified schedule regardless of treatment delays.
Safety assessments will include the incidence, nature, and severity of adverse events (AEs) and laboratory abnormalities graded per the National Cancer Institute Common Terminology Criteria for Adverse Events version 5 (NCI CTCAE v.5).
Laboratory safety assessments will include the regular monitoring of hematology, blood chemistry, and pregnancy test.
- Conditions
- Metastatic Breast Cancer
- Being tested
- Pembrolizumab, Paclitaxel
- Medical subject headings
- Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
PembrolizumabDrug
Also called Keytruda
Pembrolizumab 200 mg will be administered as a 30-minute intravenous (IV) infusion every 3 weeks beginning in Cycle 1
PaclitaxelDrug
Also called NSC-125973
Paclitaxel will be administered at the 80 mg/m2 dose via 1-hour intravenous (IV) infusion on Days 1, 8, and 15 of every 21-day cycle (beginning in Cycle 2). On days of scheduled infusions of pembrolizumab and paclitaxel (i.e., Day 1 of every cycle), paclitaxel is to be administered after infusion of pembrolizumab
| Study group | Role | What they receive |
|---|---|---|
| Pembrolizumab + Paclitaxel | Experimental | Pembrolizumab 200 mg every 3 weeks (on Day 1 [D1] of each 21-day cycle, beginning in Cycle 1) in combination with paclitaxel 80 mg/m² administered at Days 1, 8, and 15 of each 21-day cycle beginning at Cycle 2. Receives: Drug: Pembrolizumab; Drug: Paclitaxel |
What is being measured
The primary outcome is the main question the study is designed to answer.
Overall Response Rate of Pembrolizumab in Combination With Paclitaxel in HR+/HER2- Non-luminal Subtype Advanced Breast Cancer Defined by the PAM50 Assay
ORR defined as the proportion of patients with best overall response of complete response (CR) or partial response (PR), as per local investigator´s assessment and according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 criteria
Measured: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Secondary outcomes (8)
Clinical Benefit Rate (CBR)
Proportion of patients with a best overall response of CR, PR or an overall lesion response of Stable Disease (SD) or Non-PR/Non-progression disease (PD) lasting ≥ 24 weeks, based on local investigator´s assessment according to RECIST v1.1.
The CBR and its exact 90% confidence interval (CI).
Measured: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Progression Free Survival (PFS)
PFS is defined as the time from the date of allocation to the date of the first documented progression or death due to any cause occurring in the study. PFS will be assessed based on local investigator's assessment according to RECIST v1.1.
PFS will be censored if no PFS event is observed before the cut-off date. The censoring date will be the date of last adequate tumor assessment before the cut-off date. If a PFS event is observed after two or more missing or non-adequate tumor assessments, then PFS will be censored at the last adequate tumor assessment. If a PFS event is observed after a single missing or non-adequate tumor assessment, the actual date of event will be used. It is not intended to censor patients for new anticancer therapy prior to documented disease progression in the primary analysis.
Measured: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Duration of Response (DoR)
Time from the first occurrence of a documented objective response to disease progression, as determined locally by the investigator through use of RECIST v.1.1, or death from any cause, whichever occurs first.
DOR only applies to patients whose best overall response is CR or PR according to RECIST v1.1 based on tumor response data per local investigator's assessment. The start date is the date of first documented response of CR or PR (i.e., the start date of response, not the date when response was confirmed), and the end date is defined as the date of the first documented progression or death due to underlying cancer. Patients continuing without progression or death due to underlying cancer will be censored at the date of their last adequate tumor assessment.
Measured: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Time to Response (TtR)
Time from allocation to the first objective tumor response (tumor shrinkage of ≥30%) observed for patients who achieved a CR or PR.
TtR only applies to patients whose best overall response is CR or PR according to RECIST v1.1 based on tumor response data per local investigator's assessment.
Measured: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Overall Survival (OS)
Time from allocation to death from any cause. Data for patients who are alive at the time of the analysis data cutoff will be censored at the last date they were known to be alive. Data from patients without post-baseline information will be censored at the date of allocation.
The results from log-rank test will be provided. The OS curve will be estimated by the Kaplan-Meier methodology, and the 95% CI will be estimated by the Cox proportional-hazards models.
Measured: From date of randomization to death, unacceptable toxicity, consent withdrawal or study termination, whichever came first, assessed after a median follow-up of 26 months (interquartile range [IQR]: 16.6-not reached [NR]).
PFS on Study Treatment Compared to PFS on Prior Line of Therapy (Pre-PFS)
Time from allocation to the first occurrence of disease progression, as determined locally by the investigator through the use of RECIST v.1.1, or death from any cause, whichever occurs first compared to PFS on prior line of therapy.
Pre-PFS only applies to patients whose received have previous treatment for metastatic disease. The average of the Pre-PFS/PFS ratios will be calculated.
Measured: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Incidence, Duration and Severity of Adverse Events (AEs) of the Combination of Pembrolizumab With Paclitaxel
Incidence, duration and severity of AEs assessed by the NCI Common Terminology for Classification of Adverse Events (CTCAE) version 5,
Measured: Toxicities were assessed during the whole treatment period (from baseline until 90 days after a patients' final treatment, up to 35 months).
Number of Patients With Dose Interruptions, Reductions, Delays and Treatment Discontinuation of the Combination of Pembrolizumab With Paclitaxel
Quantification of dose interruptions, reductions, dose intensity, delays and treatment discontinuation will be recorded in the electronic case report form (eCRF)
Measured: Tolerability will be assessed during the whole treatment period (from baseline until patients' final treatment which is defined as the end of the Treatment Phase of the study, up to 34 months).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted31 Jan 2020
- Study start21 Jul 2020
- Primary completion10 Apr 2024
- Study completion30 Apr 2024
Why it stopped: The enrollment was stopped prematurely due to the lack of funding
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.
- Other trials for Metastatic Breast CancerStudies 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
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 20 participants (actual)
Sponsor and investigators
- Lead sponsor
- SOLTI Breast Cancer Research Group
- Sponsor type
- University, hospital or other
- Collaborators
- Merck Sharp & Dohme LLC
- Responsible party
- Sponsor
- Investigators
- Aleix Prat, MD, PhD, Principal investigator, Hospital Clinic, Barcelona, SpainEva Ciruelos, MD, PhD, Principal investigator, Hospital 12 de Octubre, Madrid, Spain
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04251169
- Sponsor's protocol ID
- SOLTI-1716
- Other IDs
- 2018-003367-58, 2018
- Acronym
- TATEN
- Status last verified
- May 2025
- First submitted
- 30 Jan 2020
- Last updated
- 3 Jun 2025
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 3 Jun 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Targeting Non-Luminal Disease by PAM50 With Pembrolizumab + Paclitaxel in Hormone Receptor-positive/HER2-negative Advanced/Metastatic Breast Cancer, Who Have Progressed on or After CDK 4/6 Inhibitor Treatment
- ClinicalTrials.gov ID
- NCT04251169
- Acronym / sponsor ID
- TATEN / SOLTI-1716
- Conditions
- Metastatic Breast Cancer
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: The enrollment was stopped prematurely due to the lack of funding
- Enrolment
- 20 participants (actual)
- Lead sponsor
- SOLTI Breast Cancer Research GroupUniversity, hospital or other
- Collaborators
- Merck Sharp & Dohme LLC
- Study start
- 21 Jul 2020 (actual)
- Primary completion
- 10 Apr 2024 (actual)
- Study completion
- 30 Apr 2024 (actual)
- First posted
- 31 Jan 2020 (actual)
- Results
- Posted 3 Jun 2025
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This is an open-label, single arm, multicenter phase II study evaluating treatment with pembrolizumab in combination with paclitaxel in patients with locally advanced or metastatic non-luminal hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) (hereafter referred to as HR+/HER2-) breast cancer who had recurrence or progression while receiving previous therapy with a cyclin-dependent kinase (CDK) inhibitor in the adjuvant setting or to treat advanced disease (or both).
Detailed description
The study will utilize a 2-stage, single arm, Simon's 2-stage design with one (efficacy) interim and a final analysis. The interim analysis will be conducted when 15 patients are evaluable for Overall Response Rate (ORR) as determined locally by the investigator through the use of Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST v.1.1). If 5 or fewer responses are observed in up to 15 patients of the evaluable population (EP), the trial will be terminated in favor of the null for futility. Otherwise, up to a further 31 patients may be evaluated, for a maximum total of 46 evaluable patients. If a total of 19 or more responses are seen at the end of the second stage, then the null will have been rejected in favor of the alternative; and further investigation of the combination is warranted.
Recruitment will not be halted during the interim analysis period. Therefore, no interruption in the accrual will be done during the interim analysis in order to maintain the dynamic of accrual in the trial.
After confirmation of all eligibility criteria, eligible patients will receive pembrolizumab 200 mg every 3 weeks (on Day 1 [D1] of each 21-day cycle, beginning in Cycle 1) in combination with paclitaxel 80 mg/m² administered at Days 1, 8, and 15 of each 21-day cycle beginning at Cycle 2. Treatment will continue until disease progression, the development of unacceptable toxicity, withdrawal of consent, 24 months from the date of the first dose of pembrolizumab, or end of study, whichever occurs first.
All patients will be followed for survival from screening until the last patient recruited has been followed for 12 months, has progressed, or has died, whichever occurs first. The patient will be followed for survival approximately every 3 months (± 21 days) until death, withdrawal of consent, loss to follow-up, or study termination by the sponsor. In addition, information regarding use of subsequent anti-cancer agents for metastatic hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-) during the survival follow-up period will be collected.
Tumor assessments per RECIST v.1.1 and Immune-Related Response Evaluation Criteria in Solid Tumors (iRECIST) will be performed every 9 weeks (63 days ± 5 days) until disease progression, treatment discontinuation, the start of new anti-cancer treatment, withdrawal of consent, death, or the end of the study, whichever occurs first. Tumor assessments will be performed on the specified schedule regardless of treatment delays.
Safety assessments will include the incidence, nature, and severity of adverse events (AEs) and laboratory abnormalities graded per the National Cancer Institute Common Terminology Criteria for Adverse Events version 5 (NCI CTCAE v.5).
Laboratory safety assessments will include the regular monitoring of hematology, blood chemistry, and pregnancy test.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Pembrolizumab + Paclitaxel | Experimental | Drug: Pembrolizumab, Drug: PaclitaxelPembrolizumab 200 mg every 3 weeks (on Day 1 [D1] of each 21-day cycle, beginning in Cycle 1) in combination with paclitaxel 80 mg/m² administered at Days 1, 8, and 15 of each 21-day cycle beginning at Cycle 2. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (22 listed)
- Male/female participants who are at least 18 years of age on the day of signing informed consent with histologically confirmed diagnosis of locally advanced or metastatic, histologically documented hormone receptor positive (estrogen receptor [ER] and/or progesterone receptor [PR] expression >1%) and human epidermal growth factor receptor 2-negative (HER2-) breast cancer by local testing, not amenable to surgical therapy will be enrolled in this study.
- The participant (or legally acceptable representative if applicable) provides written informed consent for the trial.
- Eligible for taxane therapy.
- No prior chemotherapy for inoperable locally advanced or metastatic breast cancer.
- Prior radiation therapy for metastatic disease is permitted. Subjects who were treated with radiation therapy may participate as long as at least 2 weeks have elapsed since the last dose of radiation therapy or have recovered from the effects of radiation before allocation whichever is the latest.
Key exclusion criteria (22 listed)
- A WOCBP who has a positive urine pregnancy test within 72 hours prior to Cycle 1, Day 1 (C1D1). If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required.
- Has received prior therapy with an anti-PD1, anti-PD-L1, or anti-PD-L2 agent or with an agent directed to another stimulatory or co-inhibitory T-cell receptor.
- History of hypersensitivity reactions to paclitaxel or other drugs formulated in the same solvent as paclitaxel (polyoxyethylated castor oil).
- Resolution of all acute toxic effects of prior anti-cancer therapy or major surgical procedures to National Cancer Institute Common Terminology Criteria for Adverse Events version 5.0 (NCI CTCAE v5.0) Grade ≤ 1 (except alopecia or other toxicities not considered a safety risk for the patient at investigator´s discretion).
- Note: Placement of central venous access catheter(s) (e.g., port or similar) is not considered a major surgical procedure and is therefore permitted.
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 |
|---|---|---|
| PembrolizumabAlso: KeytrudaPembrolizumab 200 mg will be administered as a 30-minute intravenous (IV) infusion every 3 weeks beginning in Cycle 1 | Drug | Pembrolizumab + Paclitaxel |
| PaclitaxelAlso: NSC-125973Paclitaxel will be administered at the 80 mg/m2 dose via 1-hour intravenous (IV) infusion on Days 1, 8, and 15 of every 21-day cycle (beginning in Cycle 2). On days of scheduled infusions of pembrolizumab and paclitaxel (i.e., Day 1 of every cycle), paclitaxel is to be administered after infusion of pembrolizumab | Drug | Pembrolizumab + Paclitaxel |
Primary outcome
Overall Response Rate of Pembrolizumab in Combination With Paclitaxel in HR+/HER2- Non-luminal Subtype Advanced Breast Cancer Defined by the PAM50 Assay
Time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
ORR defined as the proportion of patients with best overall response of complete response (CR) or partial response (PR), as per local investigator´s assessment and according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 criteria
8 secondary outcomes
Clinical Benefit Rate (CBR)
Time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Progression Free Survival (PFS)
Time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Duration of Response (DoR)
Time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Time to Response (TtR)
Time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Overall Survival (OS)
Time frame: From date of randomization to death, unacceptable toxicity, consent withdrawal or study termination, whichever came first, assessed after a median follow-up of 26 months (interquartile range [IQR]: 16.6-not reached [NR]).
PFS on Study Treatment Compared to PFS on Prior Line of Therapy (Pre-PFS)
Time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.
Incidence, Duration and Severity of Adverse Events (AEs) of the Combination of Pembrolizumab With Paclitaxel
Time frame: Toxicities were assessed during the whole treatment period (from baseline until 90 days after a patients' final treatment, up to 35 months).
Number of Patients With Dose Interruptions, Reductions, Delays and Treatment Discontinuation of the Combination of Pembrolizumab With Paclitaxel
Time frame: Tolerability will be assessed during the whole treatment period (from baseline until patients' final treatment which is defined as the end of the Treatment Phase of the study, up to 34 months).
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Jun 2025.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
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Gene Signatures to Guide HR+MBC Therapy in a Diverse Cohort
Invasive Mammary Carcinoma, Metastatic Breast Cancer
Not yet recruiting
Augmented-Reality ICG Fluorescence Second-Look for Residual Nodal Disease After Axillary Dissection in Breast Cancer
Breast Cancer, Breast Neoplasms
RecruitingPhase 2
BrAin Metastasis in tripLe Negateive Breast Cancer: IvoneScimab and Trop2 ADC
Triple-Negative Breast Cancer (TNBC), Brain Metastases
RecruitingPhase 1/2
A Study Evaluating the Efficacy and Safety of Multiple Treatment Combinations in Patients With Metastatic or Locally Advanced Breast Cancer
Metastatic Breast Cancer
RecruitingObservational study
Collection of CSF Samples From Participants With Metastatic Triple Negative Breast Cancer (TNBC) and HER2+ Breast Cancer With no Prior History Nor Active Radiographically Detectable Brain Metastases
Breast Cancer, Breast Carcinoma
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. This study is not recruiting at the moment.
Aleix Prat, MD, PhD principal investigator
Hospital Clinic, Barcelona, Spain
Eva Ciruelos, MD, PhD principal investigator
Hospital 12 de Octubre, Madrid, Spain
7 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 Pembrolizumab and Paclitaxel in people with Metastatic Breast Cancer, run by SOLTI Breast Cancer Research Group at 7 sites in Spain.
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 22 inclusion and 22 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: stopped early, as of the sponsor's last update on 3 Jun 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 7 sites in Spain. 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?
Yes. Results are posted in the registry (first posted 3 Jun 2025). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Overall Response Rate of Pembrolizumab in Combination With Paclitaxel in HR+/HER2- Non-luminal Subtype Advanced Breast Cancer Defined by the PAM50 Assay (time frame: From the date of randomization to disease progression, death, unacceptable toxicity, consent withdrawal, or study termination, whichever occurred first, assessed for up to 33 months.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 3 Jun 2025.