Breast CancerPhase 2NeoMARSNCT06650748
Multigene Risk Score Combined With Ki-67 Dynamic Assessment in Stratified Neoadjuvant Endocrine Therapy Treatment With or Without CDK4/6 Inhibitors in HR+/HER2- Breast Cancer
A Phase 2 study testing Dalpiciclib and Letrozole in people with Breast Cancer and Early-stage Breast Cancer, run by Peking University at 1 site in China.
Trial summary
This is a prospective, single-center, randomize-controlled study. The purpose of this study is to evaluate the efficacy of neoadjuvant CDK4/6 inhibitors in patients with high-risk EPclin multigene risk analysis and non-response to Ki-67 2W, and to explore predictive biomarkers for sensitivity to CDK4/6 inhibitor… Read more about this study
- Who is it for?
- Ages 18 to 70 years, women only
- Conditions the study is for
- Breast Cancer, Early-stage Breast Cancer
- What is being tested?
- Dalpiciclib and Letrozole
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteChina
- Study dates
- 1 May 2025to 1 Apr 2028
- 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 to 70 years
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Females aged 18 to 70 years;
- Patients with histologically confirmed HR+/HER2- invasive breast cancer that is sensitive to endocrine therapy. Tumor diameter >2 cm, clinically positive axillary lymph nodes not more than 2 (T2N1M0), Ki67≥+20%. Endocrine therapy sensitivity is defined as ER expression >50% by immunohistochemistry. HER-2 negativity is defined as HER-2 results of 0 or 1+ by immunohistochemistry, or negative by FISH;
- Within 28 days before the first dose of study medication, patients must have at least one measurable lesion according to RECIST 1.1 standards, as assessed by ultrasound or MRI;
- Laboratory test values: a. Absolute neutrophil count (ANC) ≥ 1,500/mm3 (1.5 × 10^9/L); b. Platelet count (PLT) ≥ 100,000/mm3 (100 × 10^9/L); c. Hemoglobin (Hb) ≥ 9 g/dL (90 g/L); d. Serum creatinine ≤ 1.5 times the upper limit of normal (ULN) or creatinine clearance ≥ 30 ml/min (based on the Cockroft-Gault formula); e. Total bilirubin (BIL) ≤ 1.5 times the upper limit of normal (ULN), Gilbert's syndrome; f. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels ≤ 2.5 times the upper limit of normal (ULN); g. INR or PT ≤1.5 ULN, APTT ≤1.5 ULN.
- Subject agrees to collect tumor biopsy specimen during the screening period;
- Subject signed the informed consent form, expressing willingness and ability to comply with the planned visits, study treatments, laboratory tests, and other trial procedures.
Who cannot join
- Coexisted with other malignant tumors within 5 years prior to first medication, except for cured squamous cell carcinoma of the skin, basal cell carcinoma, non-muscle-invasive bladder cancer, carcinoma in situ of the cervix/breast, etc;
- Had a serious infection within 1 month before screening or required systemic treatment for any active infection within 2 weeks before first medication;
- History or current presence of autoimmune diseases, including but not limited to Crohn's disease, ulcerative colitis, systemic lupus erythematosus, sarcoidosis, Wegener's syndrome (granulomatosis with polyangiitis, Graves' disease, rheumatoid arthritis, hypophysitis, uveitis), autoimmune hepatitis, systemic sclerosis (scleroderma, etc.), Hashimoto's thyroiditis (exceptions are noted below), autoimmune vasculitis, autoimmune neuropathy (Guillain-Barre syndrome), etc. The following exceptions apply: Type I diabetes, thyroid dysfunction requiring only hormone replacement therapy (including thyroid dysfunction caused by autoimmune thyroid disease), psoriasis or vitiligo not requiring systemic treatment;
- History of organ transplantation or allogeneic hematopoietic stem cell transplantation;
- Patients who received systemic anti-cancer treatment within 2 weeks before the first dose, including chemotherapy, immunotherapy, hormone therapy, biological therapy (cytokines or growth factors that control the progression of cancer);
- Metastatic breast cancer;
- Positive for human immunodeficiency virus antibodies (HIV-Ab) or syphilis antibodies (Anti-TP); positive for hepatitis C virus antibodies (HCV-Ab), with hepatitis C virus RNA quantification > the upper limit of the normal value of the detection unit; positive for hepatitis B surface antigen (HBsAg) and/or hepatitis B core antibodies (HBcAb), with HBV DNA quantification > the lower limit of detection of the detection unit;
- History of alcohol abuse or drug abuse.
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Multigene Risk Score Combined With Ki-67 Dynamic Assessment in Stratified Neoadjuvant Endocrine Therapy Treatment With or Without CDK4/6 Inhibitors in HR+/HER2- Breast Cancer: a Randomize-controlled Study
This is a prospective, single-center, randomize-controlled study. The purpose of this study is to evaluate the efficacy of neoadjuvant CDK4/6 inhibitors in patients with high-risk EPclin multigene risk analysis and non-response to Ki-67 2W, and to explore predictive biomarkers for sensitivity to CDK4/6 inhibitor therapy.
Read the detailed description
China is a country with a high incidence of breast cancer. For operable hormone receptor-positive (HR+) / human epidermal growth factor receptor 2-negative (HER2-) breast cancer, traditional neoadjuvant chemotherapy often fails to achieve clinical complete response (CCR) and has poor tolerability. Endocrine therapy plays a significant role in the treatment of advanced and early-stage HR+/HER2- breast cancer, but its efficacy in neoadjuvant settings needs further exploration. Studies have shown that the CCR and breast conservation rate of neoadjuvant endocrine therapy for HR+/HER2- breast cancer are similar to those of neoadjuvant chemotherapy, with lower toxicity. Therefore, by precisely stratifying the recurrence risk of HR+/HER2- patients and treating them according to different risk levels, the response rate to neoadjuvant endocrine therapy can be further improved, which would be more beneficial for the patients. With the clinical application of CDK4/6 inhibitors, the effectiveness of neoadjuvant endocrine therapy is expected to be enhanced.
In PALLET study, the combination of palbociclib and letrozole significantly inhibited Ki-67 expression, leading to a higher number of patients achieving a state of cell cycle arrest (CCCA) (defined as Ki-67≤2.7%). NeoMONARCH study suggests that a regimen containing abemaciclib is significantly superior to anastrozole monotherapy, with statistical significance (P < 0.001). The NeoPAL and CORALLEEN studies indicate that neoadjuvant endocrine therapy with palbociclib or ribociclib is comparable in efficacy to neoadjuvant chemotherapy, yet has fewer side effects.
EndoPredict (12-gene assay, EPclin) is a second-generation multigene testing scoring tool that combines the molecular biological status of the tumor with clinical factors (tumor size and lymph node status). For early-stage HR+/HER2- breast cancer patients, the EPclin test result helps to distinguish between low and high recurrence risk populations, allowing for a more precise assessment of patient prognosis. In the validation study for premenopausal patients, a total of 385 patients with stage ≤pT3 and pN0~1, who received only endocrine therapy for ER+/HER2- early invasive breast cancer, were enrolled. The results showed that the 10-year distant recurrence-free survival (DRFS) rate for patients in the EPclin low-risk group reached 97%, while the 10-year DRFS rate for the EPclin high-risk group was 76% (P=0.004). For postmenopausal patients, the prognostic value of EPclin was independently validated through the ABCSG6\&8 study. The study included 1,702 patients with ER+/HER2- early invasive breast cancer who underwent surgery and received only five years of endocrine therapy. The results showed that the 10-year distant recurrence rate for patients in the EPclin low-risk group was 4%, while the 10-year distant recurrence rates for patients in the EPclin high-risk group were 28% and 22% (P<0.001). A retrospective analysis of ABCSG-34 demonstrated that for patients undergoing neoadjuvant endocrine therapy, the application of EPclin for prognostic assessment revealed a negative correlation between risk levels and residual cancer burden (RCB). That is, among patients receiving neoadjuvant endocrine therapy (NET), a higher proportion of low-risk patients compared to high-risk patients ultimately had an RCB of 0-I.
This study focuses on early-stage HR+/HER2- breast cancer, conducting recurrence risk analysis through EPclin multigene testing, and integrating the dynamic changes of Ki67 after two weeks of neoadjuvant endocrine therapy. Patients are risk-stratified and treated with or without CDK4/6 inhibitors. The study explores the improvement in PEPI scores after surgery and analyzes the effectiveness of multigene testing combined with Ki67 dynamic changes as a predictor for the efficacy of CDK4/6 inhibitor treatment in HR+/HER2- breast cancer with high recurrence risk and insensitivity to endocrine therapy. The study also seeks to explore methods for predicting sensitivity to CDK4/6 inhibitor treatment.
- Conditions
- Breast Cancer, Early-stage Breast Cancer
- Being tested
- Dalpiciclib, Letrozole
- Keywords
- Early-stage Breast Cancer, neoadjuvant endocrine therapy, CDK4/6, HR+/HER2-
- Medical subject headings
- Breast Neoplasms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
DalpiciclibDrug
Dalpiciclib, oral administration, 125g each time, once daily, days 1-21, with a 28-day cycle (3 weeks on/1 week off). Continuous medication for 6 cycles, or disease progression, intolerable toxicity, withdrawal from the study for any reason or death, whichever occurs first; or after researcher's judgement, patient would no longer benefit from the treatment.
LetrozoleDrug
2.5 mg, oral, once daily (continuously), with a 28-day cycle. Continuous medication for 6 cycles, or disease progression, intolerable toxicity, withdrawal from the study for any reason or death, whichever occurs first. Refer to drug instructions for specific usage
| Study group | Role | What they receive |
|---|---|---|
| Arm 1 | Experimental | gene high-risk according to Epclin who are insensitive to single-agent AI treatment for two weeks Receives: Drug: Dalpiciclib; Drug: Letrozole |
| Arm 2 | Experimental | gene high-risk according to Epclin who are sensitive to single-agent AI treatment for two weeks and gene low-risk according to Epclin who are insensitive to single-agent AI treatment for two weeks, randomly assigned to letrozole treatment arm Receives: Drug: Letrozole |
| Arm 3 | Experimental | gene high-risk according to Epclin who are sensitive to single-agent AI treatment for two weeks and gene low-risk according to Epclin who are insensitive to single-agent AI treatment for two weeks, randomly assigned to Dalpiciclib and letrozole treatment arm Receives: Drug: Dalpiciclib; Drug: Letrozole |
| Arm 4 | Experimental | gene low-risk according to Epclin who are sensitive to single-agent AI treatment for two weeks Receives: Drug: Letrozole |
What is being measured
The primary outcome is the main question the study is designed to answer.
1. The proportion of (PEPI score 0 + pCR) in patients with discordant EPclin scores and Ki67 assessments who were randomly assigned to the "+CDK4/6i" group
proportion of subjects who were PEPI score 0 or pCR after neoadjuvant endocrine therapy in patients with discordant EPclin scores and Ki67 assessments who were randomly assigned to the "+CDK4/6i" group
Measured: Start of treatment until 6-month follow-up
Secondary outcomes (12)
The change in Ki-67 compared to the baseline after two weeks of treatment
Measured: Start of treatment until 2-week follow-up
The change in Ki-67 after surgery compared to two weeks post-treatment
Measured: Start of treatment until 6-month follow-up
Rate of patients with pCR (pathological complete response) after surgery
Measured: Start of treatment until 6-month follow-up
ORR
Objective response rate: proportion of subjects who achieved complete remission (CR) or partial remission (PR) by primary tumor imaging evaluation
Measured: Start of treatment until 6-month follow-up
CCCA rate
Cell cycle arrest: defined as Ki-67≤2.7%
Measured: Start of treatment until 6-month follow-up
Breast conservation rate
Measured: Start of treatment until 6-month follow-up
The proportion of PEPI 0-1 in patients with gene-high risk who are sensitive to single-agent AI treatment for two weeks and treated with AI in combination with Dalpiciclib
Measured: Start of treatment until 6-month follow-up
The proportion of PEPI 0-1 in patients with gene-low risk who are insensitive to single-agent AI treatment for two weeks and treated with AI in combination with Dalpiciclib
Measured: Start of treatment until 6-month follow-up
The proportion of patients at high risk according to Epclin who are downgraded to low risk after neoadjuvant treatment
Measured: Start of treatment until 6-month follow-up
EFS
Event free survival: time from the start of treatment to the first occurrence of any of the following events: disease progression, local or distant recurrence, or death due to any cause
Measured: Start of treatment until 24-month follow-up
Incidence of adverse events (AE)
Measured: Start of treatment until 6-month follow-up
Incidence of serious adverse events (SAE)
Measured: Start of treatment until 6-month follow-up
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Oct 2024
- Study start1 May 2025
- Primary completion1 Oct 2027 (estimated)
- Study completion1 Apr 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Breast CancerStudies of the same condition, open and under way.
- More trials run by Peking UniversityThe 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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Peking University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Tao OUYANG, Peking University
- Investigators
- Zhaoqing Fan, Principal investigator, Peking University Cancer Hospital & Institute
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06650748
- Sponsor's protocol ID
- OBU-BC-II-164
- Acronym
- NeoMARS
- Status last verified
- Mar 2026
- First submitted
- 18 Oct 2024
- Last updated
- 17 Mar 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 17 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Multigene Risk Score Combined With Ki-67 Dynamic Assessment in Stratified Neoadjuvant Endocrine Therapy Treatment With or Without CDK4/6 Inhibitors in HR+/HER2- Breast Cancer: a Randomize-controlled Study
- ClinicalTrials.gov ID
- NCT06650748
- Acronym / sponsor ID
- NeoMARS / OBU-BC-II-164
- Conditions
- Breast Cancer, Early-stage Breast Cancer
- Keywords
- Early-stage Breast Cancer, neoadjuvant endocrine therapy, CDK4/6, HR+/HER2-
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Enrolling by invitation
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Peking UniversityUniversity, hospital or other
- Study start
- 1 May 2025 (actual)
- Primary completion
- 1 Oct 2027 (estimated)
- Study completion
- 1 Apr 2028 (estimated)
- First posted
- 21 Oct 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 prospective, single-center, randomize-controlled study. The purpose of this study is to evaluate the efficacy of neoadjuvant CDK4/6 inhibitors in patients with high-risk EPclin multigene risk analysis and non-response to Ki-67 2W, and to explore predictive biomarkers for sensitivity to CDK4/6 inhibitor therapy.
Detailed description
China is a country with a high incidence of breast cancer. For operable hormone receptor-positive (HR+) / human epidermal growth factor receptor 2-negative (HER2-) breast cancer, traditional neoadjuvant chemotherapy often fails to achieve clinical complete response (CCR) and has poor tolerability. Endocrine therapy plays a significant role in the treatment of advanced and early-stage HR+/HER2- breast cancer, but its efficacy in neoadjuvant settings needs further exploration. Studies have shown that the CCR and breast conservation rate of neoadjuvant endocrine therapy for HR+/HER2- breast cancer are similar to those of neoadjuvant chemotherapy, with lower toxicity. Therefore, by precisely stratifying the recurrence risk of HR+/HER2- patients and treating them according to different risk levels, the response rate to neoadjuvant endocrine therapy can be further improved, which would be more beneficial for the patients. With the clinical application of CDK4/6 inhibitors, the effectiveness of neoadjuvant endocrine therapy is expected to be enhanced.
In PALLET study, the combination of palbociclib and letrozole significantly inhibited Ki-67 expression, leading to a higher number of patients achieving a state of cell cycle arrest (CCCA) (defined as Ki-67≤2.7%). NeoMONARCH study suggests that a regimen containing abemaciclib is significantly superior to anastrozole monotherapy, with statistical significance (P < 0.001). The NeoPAL and CORALLEEN studies indicate that neoadjuvant endocrine therapy with palbociclib or ribociclib is comparable in efficacy to neoadjuvant chemotherapy, yet has fewer side effects.
EndoPredict (12-gene assay, EPclin) is a second-generation multigene testing scoring tool that combines the molecular biological status of the tumor with clinical factors (tumor size and lymph node status). For early-stage HR+/HER2- breast cancer patients, the EPclin test result helps to distinguish between low and high recurrence risk populations, allowing for a more precise assessment of patient prognosis. In the validation study for premenopausal patients, a total of 385 patients with stage ≤pT3 and pN0~1, who received only endocrine therapy for ER+/HER2- early invasive breast cancer, were enrolled. The results showed that the 10-year distant recurrence-free survival (DRFS) rate for patients in the EPclin low-risk group reached 97%, while the 10-year DRFS rate for the EPclin high-risk group was 76% (P=0.004). For postmenopausal patients, the prognostic value of EPclin was independently validated through the ABCSG6\&8 study. The study included 1,702 patients with ER+/HER2- early invasive breast cancer who underwent surgery and received only five years of endocrine therapy. The results showed that the 10-year distant recurrence rate for patients in the EPclin low-risk group was 4%, while the 10-year distant recurrence rates for patients in the EPclin high-risk group were 28% and 22% (P<0.001). A retrospective analysis of ABCSG-34 demonstrated that for patients undergoing neoadjuvant endocrine therapy, the application of EPclin for prognostic assessment revealed a negative correlation between risk levels and residual cancer burden (RCB). That is, among patients receiving neoadjuvant endocrine therapy (NET), a higher proportion of low-risk patients compared to high-risk patients ultimately had an RCB of 0-I.
This study focuses on early-stage HR+/HER2- breast cancer, conducting recurrence risk analysis through EPclin multigene testing, and integrating the dynamic changes of Ki67 after two weeks of neoadjuvant endocrine therapy. Patients are risk-stratified and treated with or without CDK4/6 inhibitors. The study explores the improvement in PEPI scores after surgery and analyzes the effectiveness of multigene testing combined with Ki67 dynamic changes as a predictor for the efficacy of CDK4/6 inhibitor treatment in HR+/HER2- breast cancer with high recurrence risk and insensitivity to endocrine therapy. The study also seeks to explore methods for predicting sensitivity to CDK4/6 inhibitor treatment.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 4
| Arm | Type | Receives |
|---|---|---|
| Arm 1 | Experimental | Drug: Dalpiciclib, Drug: Letrozolegene high-risk according to Epclin who are insensitive to single-agent AI treatment for two weeks |
| Arm 2 | Experimental | Drug: Letrozolegene high-risk according to Epclin who are sensitive to single-agent AI treatment for two weeks and gene low-risk according to Epclin who are insensitive to single-agent AI treatment for two weeks, randomly assigned to letrozole treatment arm |
| Arm 3 | Experimental | Drug: Dalpiciclib, Drug: Letrozolegene high-risk according to Epclin who are sensitive to single-agent AI treatment for two weeks and gene low-risk according to Epclin who are insensitive to single-agent AI treatment for two weeks, randomly assigned to Dalpiciclib and letrozole treatment arm |
| Arm 4 | Experimental | Drug: Letrozolegene low-risk according to Epclin who are sensitive to single-agent AI treatment for two weeks |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Females aged 18 to 70 years;
- Patients with histologically confirmed HR+/HER2- invasive breast cancer that is sensitive to endocrine therapy. Tumor diameter >2 cm, clinically positive axillary lymph nodes not more than 2 (T2N1M0), Ki67≥+20%. Endocrine therapy sensitivity is defined as ER expression >50% by immunohistochemistry. HER-2 negativity is defined as HER-2 results of 0 or 1+ by immunohistochemistry, or negative by FISH;
- Within 28 days before the first dose of study medication, patients must have at least one measurable lesion according to RECIST 1.1 standards, as assessed by ultrasound or MRI;
- Laboratory test values: a. Absolute neutrophil count (ANC) ≥ 1,500/mm3 (1.5 × 10^9/L); b. Platelet count (PLT) ≥ 100,000/mm3 (100 × 10^9/L); c. Hemoglobin (Hb) ≥ 9 g/dL (90 g/L); d. Serum creatinine ≤ 1.5 times the upper limit of normal (ULN) or creatinine clearance ≥ 30 ml/min (based on the Cockroft-Gault formula); e. Total bilirubin (BIL) ≤ 1.5 times the upper limit of normal (ULN), Gilbert's syndrome; f. Aspartate aminotransferase (AST) or alanine aminotransferase (ALT) levels ≤ 2.5 times the upper limit of normal (ULN); g. INR or PT ≤1.5 ULN, APTT ≤1.5 ULN.
- Subject agrees to collect tumor biopsy specimen during the screening period;
Key exclusion criteria (8 listed)
- Coexisted with other malignant tumors within 5 years prior to first medication, except for cured squamous cell carcinoma of the skin, basal cell carcinoma, non-muscle-invasive bladder cancer, carcinoma in situ of the cervix/breast, etc;
- Had a serious infection within 1 month before screening or required systemic treatment for any active infection within 2 weeks before first medication;
- History or current presence of autoimmune diseases, including but not limited to Crohn's disease, ulcerative colitis, systemic lupus erythematosus, sarcoidosis, Wegener's syndrome (granulomatosis with polyangiitis, Graves' disease, rheumatoid arthritis, hypophysitis, uveitis), autoimmune hepatitis, systemic sclerosis (scleroderma, etc.), Hashimoto's thyroiditis (exceptions are noted below), autoimmune vasculitis, autoimmune neuropathy (Guillain-Barre syndrome), etc. The following exceptions apply: Type I diabetes, thyroid dysfunction requiring only hormone replacement therapy (including thyroid dysfunction caused by autoimmune thyroid disease), psoriasis or vitiligo not requiring systemic treatment;
- History of organ transplantation or allogeneic hematopoietic stem cell transplantation;
- Patients who received systemic anti-cancer treatment within 2 weeks before the first dose, including chemotherapy, immunotherapy, hormone therapy, biological therapy (cytokines or growth factors that control the progression 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 |
|---|---|---|
| DalpiciclibDalpiciclib, oral administration, 125g each time, once daily, days 1-21, with a 28-day cycle (3 weeks on/1 week off). Continuous medication for 6 cycles, or disease progression, intolerable toxicity, withdrawal from the study for any reason or death, whichever occurs first; or after researcher's judgement, patient would no longer benefit from the treatment. | Drug | Arm 1, Arm 3 |
| Letrozole2.5 mg, oral, once daily (continuously), with a 28-day cycle. Continuous medication for 6 cycles, or disease progression, intolerable toxicity, withdrawal from the study for any reason or death, whichever occurs first. Refer to drug instructions for specific usage | Drug | Arm 1, Arm 2, Arm 3, Arm 4 |
Primary outcome
1. The proportion of (PEPI score 0 + pCR) in patients with discordant EPclin scores and Ki67 assessments who were randomly assigned to the "+CDK4/6i" group
Time frame: Start of treatment until 6-month follow-up
proportion of subjects who were PEPI score 0 or pCR after neoadjuvant endocrine therapy in patients with discordant EPclin scores and Ki67 assessments who were randomly assigned to the "+CDK4/6i" group
12 secondary outcomes
The change in Ki-67 compared to the baseline after two weeks of treatment
Time frame: Start of treatment until 2-week follow-up
The change in Ki-67 after surgery compared to two weeks post-treatment
Time frame: Start of treatment until 6-month follow-up
Rate of patients with pCR (pathological complete response) after surgery
Time frame: Start of treatment until 6-month follow-up
ORR
Time frame: Start of treatment until 6-month follow-up
CCCA rate
Time frame: Start of treatment until 6-month follow-up
Breast conservation rate
Time frame: Start of treatment until 6-month follow-up
The proportion of PEPI 0-1 in patients with gene-high risk who are sensitive to single-agent AI treatment for two weeks and treated with AI in combination with Dalpiciclib
Time frame: Start of treatment until 6-month follow-up
The proportion of PEPI 0-1 in patients with gene-low risk who are insensitive to single-agent AI treatment for two weeks and treated with AI in combination with Dalpiciclib
Time frame: Start of treatment until 6-month follow-up
The proportion of patients at high risk according to Epclin who are downgraded to low risk after neoadjuvant treatment
Time frame: Start of treatment until 6-month follow-up
EFS
Time frame: Start of treatment until 24-month follow-up
Incidence of adverse events (AE)
Time frame: Start of treatment until 6-month follow-up
Incidence of serious adverse events (SAE)
Time frame: Start of treatment until 6-month follow-up
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 17 Mar 2026.
- Individual participant dataSharing planned: No
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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.
Zhaoqing Fan principal investigator
Peking University Cancer Hospital & Institute
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Dalpiciclib and Letrozole in people with Breast Cancer and Early-stage Breast Cancer, run by Peking University at 1 site in China.
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 6 inclusion and 8 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: enrolling by invitation, as of the sponsor's last update on 17 Mar 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in China. 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?
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?
1. The proportion of (PEPI score 0 + pCR) in patients with discordant EPclin scores and Ki67 assessments who were randomly assigned to the "+CDK4/6i" group (time frame: Start of treatment until 6-month follow-up). 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 17 Mar 2026.