Dalpiciclib, Anti-HER2 Therapy, and Endocrine Therapy for Hormone-Receptor-Positive, HER2-Positive Metastatic Breast Cancer

May 20, 2026 updated by: Jia-Jia Huang, Sun Yat-sen University

Evaluating the Efficacy and Safety of Dalpiciclib Plus Anti-HER2 Therapy and Endocrine Therapy in Patients With Induction-Treated Hormone-Receptor-Positive, HER2-Positive Metastatic Breast Cancer

Efficacy and Safety of Dalpiciclib Combined with Anti-HER2 Targeted Therapy and Endocrine Therapy as First-line Maintenance Treatment for Patients with Recurrent or Metastatic Hormone-Receptor-Positive, HER2-positive Breast Cancer.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Detailed Description

This is a multicenter, single-arm, open-label, phase II clinical trial evaluating the efficacy and safety of dalpiciclib (a novel oral CDK4/6 inhibitor) combined with anti-HER2 therapy and endocrine therapy as maintenance treatment in patients with hormone receptor-positive (HR+)/HER2-positive metastatic breast cancer who have completed induction systemic therapy without disease progression.

Triple-positive (HR+/HER2+) metastatic breast cancer represents a unique subtype requiring dual pathway inhibition. Current standard first-line induction therapy includes taxane-based chemotherapy combined with trastuzumab and pertuzumab (THP) or pyrotinib (THPy), followed by maintenance with anti-HER2 therapy plus endocrine therapy. However, approximately 50% of patients progress within 18 months during maintenance therapy.

This study explores the addition of dalpiciclib to standard anti-HER2 and endocrine maintenance therapy to prolong progression-free survival. Dalpiciclib, the first domestically developed CDK4/6 inhibitor in China, has demonstrated favorable efficacy and a manageable safety profile in HR+/HER2- advanced breast cancer, with a lower incidence of febrile neutropenia and no observed interstitial lung disease.

Study Type

Interventional

Enrollment (Estimated)

57

Phase

  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • China
    • GUANGZHOU
      • Guangdong, GUANGZHOU, China, 510060
        • Recruiting
        • Sun yat-Sen University Cancer Center, Guangzhou, Yuexiu District

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Females aged 18 to 75 years with pathologically confirmed metastatic or locally advanced unresectable breast cancer.
  2. Hormone receptor (HR)-positive and HER2-positive.
  3. Patients with no evidence of disease progression (including CR, PR, or SD)after 4-8 cycles of first-line systemic anti-tumor therapy.
  4. ECOG Performance Status: 0-1.

Exclusion Criteria:

  1. Symptomatic active brain metastases or extensive leptomeningeal metastases.
  2. History of Grade 3 or 4 allergic reaction related to the study drugs.
  3. Currently receiving other anti-tumor therapies.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Dalpiciclib + Endocrine Therapy + Trastuzumab ± Pertuzumab or Pyrotinib
Drug: Dalpiciclib
Oral CDK4/6 inhibitor (dose modification permitted for toxicity management)
Drug: Trastuzumab (Herceptin)
Subcutaneous, 600mg Q3W; IV: 8mg/kg (loading) → 6mg/kg Q3W
Drug: Pertuzumab
IV: 840mg (loading) → 420mg Q3W
Drug: Pyrotinib
240mg qd Week 1 → 320mg qd from Week 2 (max dose); loperamide prophylaxis for diarrhea
Drug: Endocrine Therapy 1
Letrozole 2.5mg, Anastrozole 1mg, Exemestane 25mg, or Fulvestrant 0.5g IM on Days 1, 28 (initial: Days 1, 15, 28)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Progression-Free Survival (PFS)
Time Frame: From date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Time from enrollment to radiographic disease progression (per RECIST 1.1) or death from any cause, whichever occurs first
From date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Objective Response Rate (ORR)
Time Frame: From date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Proportion of patients achieving Complete Response (CR) or Partial Response (PR) per RECIST 1.1
From date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Overall Survival (OS)
Time Frame: From randomization until the end of the study (approximately 36 months)
Time from enrollment to death from any cause
From randomization until the end of the study (approximately 36 months)
Safety and Tolerability
Time Frame: From date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Incidence, type, severity, and relationship of adverse events (AEs) graded by NCI CTCAE v5.0
From date of enrollment until the date of first documented progression or date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Disease-Specific Quality of Life Assessed by EORTC QLQ-BR45
Time Frame: From the date of enrollment until the date of first documented progression or the date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Breast Cancer-Specific Module (EORTC QLQ-BR45). The EORTC QLQ-BR45 contains 45 items divided into functional and symptom scales evaluating breast cancer-specific issues and treatment side effects. All scales range in score from 0 to 100. A higher score for a functional scale represents a higher/healthy level of functioning, whereas a higher score for a symptom scale represents a higher level of breast cancer-related symptomatology or treatment-related problems.
From the date of enrollment until the date of first documented progression or the date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Quality of Life Assessed by EORTC QLQ-C30
Time Frame: From the date of enrollment until the date of first documented progression or the date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.
Assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30). The EORTC QLQ-C30 consists of 30 items incorporating 5 functional scales, 3 symptom scales, a global health status scale, and 6 single items. All scales and single-item measures range in score from 0 to 100. A higher score for a functional scale or global health status represents a higher/healthy level of functioning, whereas a higher score for a symptom scale/item represents a higher level of symptomatology or problems.
From the date of enrollment until the date of first documented progression or the date of death from any cause, whichever came first, assessed up to 2 years after the last participant completes treatment.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sun Yat-sen University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

June 1, 2026

Primary Completion (Estimated)

November 1, 2028

Study Completion (Estimated)

November 1, 2029

Study Registration Dates

First Submitted

May 6, 2026

First Submitted That Met QC Criteria

May 20, 2026

First Posted (Actual)

May 28, 2026

Study Record Updates

Last Update Posted (Actual)

May 28, 2026

Last Update Submitted That Met QC Criteria

May 20, 2026

Last Verified

May 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • DALTINA

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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