Combining Dalpiciclib with Endocrine Therapy for Advanced Breast Cancer After CDK4/6 Inhibitor Failure

An Exploratory Study on Predicting the Efficacy of Dalpiciclib in Combination With Endocrine Therapy for HR-Positive and HER2-Negative Recurrent/Metastatic Breast Cancer Patients After CDK4/6 Inhibitor Treatment Failure Using 18F-FES PET/CT

This study is testing if combining Dalpiciclib with hormone therapy can help people with advanced breast cancer who didn’t respond to previous CDK4/6 inhibitors.

Quick facts

• Phase: Phase 3
• Study type: Interventional
• Enrollment: 80 (estimated)
• Ages: 18 Years to 80 Years
• Sex: All
• Sponsor: Peking Union Medical College Hospital (Academic / other)
• Drugs / interventions: chemotherapy
• Locations: 1 site (Beijing, Beijing Municipality)
• Trial ID: NCT05861830 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the effectiveness of Dalpiciclib combined with physician-selected endocrine therapy in patients with advanced breast cancer who have previously failed treatment with CDK4/6 inhibitors. The study utilizes 18F-FES PET/CT imaging to evaluate estrogen receptor expression in systemic lesions, providing a non-invasive alternative to traditional biopsy methods. By exploring this combination therapy, the trial aims to improve patient survival outcomes in a population lacking established treatment options after CDK4/6 inhibitor failure.

Who should consider this trial

Good fit: Ideal candidates include women with HR-positive, HER2-negative advanced breast cancer who have experienced treatment failure with CDK4/6 inhibitors.

Not a fit: Patients with HR-negative or HER2-positive breast cancer, or those who have not previously received CDK4/6 inhibitors, may not benefit from this study.

Why it matters

Potential benefit: If successful, this approach could provide a new treatment option for patients with advanced breast cancer who have not responded to standard therapies.

How similar studies have performed: Other studies have shown success with similar approaches, indicating potential for this combination therapy to yield positive outcomes.

Eligibility criteria

Inclusion Criteria:

* The recent pathology results showed HR-positive and HER2-negative.
* 18F-FES-PET/CT showed at least one ER-positive lesion.
* Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) score: 0-2 points.
* Expected survival time ≥ 3 months.
* Previous antitumor therapy: (1) (neo)adjuvant treatment with Palbociclib or Abemaciclib or Ribociclib or relapse after adjuvant treatment with Palbociclib or Abemaciclib or Ribociclib; (2) receiving Palbociclib or Abemaciclib or Ribociclib-based treatment in the context of metastatic breast cancer or disease progression after treatment; (3) previously received ≤1 line of chemotherapy for recurrent or metastatic breast cancer; (4) previously received ≤3 lines of endocrine therapy for recurrent or metastatic breast cancer.
* Willing to undergo 18F-FDG PET/CT standard imaging.
* At least one measurable lesion outside the skull according to RECIST V1.1.
* The function of important organs meets the requirements.
* The subjects have recovered from any adverse event related to previous tumor treatment (≤ Grade 1) before the first administration of the investigational drug.

Exclusion Criteria:

* 18F-FES-PET/CT shows that all lesions are ER-negative.
* Previously received treatment with Dalpiciclib.
* MRI or lumbar puncture confirms leptomeningeal metastasis.
* Imaging confirms central nervous system metastasis.
* Participants with visceral crisis, rapid disease progression, and patients not suitable for endocrine therapy.
* Participants with ascites, baseline pleural effusion with clinical symptoms, and pericardial effusion requiring drainage within the first 4 weeks of treatment.
* Unable to swallow, intestinal obstruction, or other factors that affect drug administration and absorption.
* Participants diagnosed with any other malignancy within the past 5 years, excluding non-melanoma skin cancer treated with curative intent. Basal cell or squamous cell skin cancer, or cervical intraepithelial neoplasia and papillary thyroid cancer.
* Participants who have undergone major surgery or suffered a major injury within 4 weeks before starting treatment, or are expected to undergo major surgical treatment.
* Known history of allergy to the components of this treatment regimen.

Where this trial is running

Beijing, Beijing Municipality

• Peking Union Medical College Hospital — Beijing, Beijing Municipality, China (Recruiting)

Study contacts

• Study coordinator: Bo Pan, M.D.

Conditions Advanced Breast Cancer